chore(rollout): nice collored cli

* feat(policies): add EO-1 model

* chore(eo1): adjust policy_eo1_README.md to to avoid duplicate with eo1.mdx

* chore(eo1): remove policy_eo1_README.md, link eo1.mdx in policy folder

---------

Co-authored-by: Pepijn <138571049+pkooij@users.noreply.github.com>

.github/workflows/documentation-upload-pr.yml

@@ -33,7 +33,7 @@ jobs:
       github.event.workflow_run.event == 'pull_request' &&
       github.event.workflow_run.conclusion == 'success' &&
       github.repository == 'huggingface/lerobot'
-    uses: huggingface/doc-builder/.github/workflows/upload_pr_documentation.yml@9ad2de8582b56c017cb530c1165116d40433f1c6  # main
+    uses: huggingface/doc-builder/.github/workflows/upload_pr_documentation.yml@2430c1ec91d04667414e2fa31ecfc36c153ea391  # main
     with:
       package_name: lerobot
     secrets:

.github/workflows/documentation.yml

@@ -55,7 +55,7 @@ jobs:
       github.repository == 'huggingface/lerobot'
     permissions:
       contents: read
-    uses: huggingface/doc-builder/.github/workflows/build_main_documentation.yml@90b4ee2c10b81b5c1a6367c4e6fc9e2fb510a7e3  # main
+    uses: huggingface/doc-builder/.github/workflows/build_main_documentation.yml@2430c1ec91d04667414e2fa31ecfc36c153ea391  # main
     with:
       commit_sha: ${{ github.sha }}
       package: lerobot
@@ -78,7 +78,7 @@ jobs:
     permissions:
       contents: read
       pull-requests: write
-    uses: huggingface/doc-builder/.github/workflows/build_pr_documentation.yml@90b4ee2c10b81b5c1a6367c4e6fc9e2fb510a7e3  # main
+    uses: huggingface/doc-builder/.github/workflows/build_pr_documentation.yml@2430c1ec91d04667414e2fa31ecfc36c153ea391  # main
     with:
       commit_sha: ${{ github.event.pull_request.head.sha }}
       pr_number: ${{ github.event.number }}

.github/workflows/stale.yml

@@ -24,14 +24,14 @@ on:
 
 env:
   CLOSE_ISSUE_MESSAGE: >
-    This issue was closed because it has been stalled for 14 days with no activity.
+    This issue was closed because it has been stalled for 30 days with no activity.
     Feel free to reopen if is still relevant, or to ping a collaborator if you have any questions.
   CLOSE_PR_MESSAGE: >
-    This PR was closed because it has been stalled for 21 days with no activity.
+    This PR was closed because it has been stalled for 30 days with no activity.
     Feel free to reopen if is still relevant, or to ping a collaborator if you have any questions.
   WARN_ISSUE_MESSAGE: >
     This issue has been automatically marked as stale because it has not had
-    recent activity (6 months). It will be closed if no further activity occurs.
+    recent activity (1 year). It will be closed if no further activity occurs.
     Any change, comment or update to this issue will reset this count.
     Thank you for your contributions.
   WARN_PR_MESSAGE: >
@@ -59,10 +59,10 @@ jobs:
           stale-pr-label: stale
           exempt-issue-labels: never-stale
           exempt-pr-labels: never-stale
-          days-before-issue-stale: 180
-          days-before-issue-close: 14
+          days-before-issue-stale: 365
+          days-before-issue-close: 30
           days-before-pr-stale: 365
-          days-before-pr-close: 21
+          days-before-pr-close: 30
           delete-branch: true
           close-issue-message: ${{ env.CLOSE_ISSUE_MESSAGE }}
           close-pr-message: ${{ env.CLOSE_PR_MESSAGE }}

MANIFEST.in

@@ -1,3 +1,4 @@
 include src/lerobot/templates/lerobot_modelcard_template.md
+include src/lerobot/templates/lerobot_rewardmodel_modelcard_template.md
 include src/lerobot/datasets/card_template.md
 include src/lerobot/envs/metaworld_config.json

docker/Dockerfile.internal

@@ -18,9 +18,8 @@
 # docker build -f docker/Dockerfile.internal -t lerobot-internal .
 
 # Configure the base image for CI with GPU access
-# TODO(Steven): Bump these versions
-ARG CUDA_VERSION=12.4.1
-ARG OS_VERSION=22.04
+ARG CUDA_VERSION=12.6.3
+ARG OS_VERSION=24.04
 FROM nvidia/cuda:${CUDA_VERSION}-base-ubuntu${OS_VERSION}
 
 # Define Python version argument
@@ -36,16 +35,13 @@ ENV DEBIAN_FRONTEND=noninteractive \
 
 # Install Python, system dependencies, and uv (as root)
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    software-properties-common build-essential git curl \
-    libglib2.0-0 libgl1-mesa-glx libegl1-mesa ffmpeg \
+    build-essential git curl \
+    libglib2.0-0 libgl1 libegl1 ffmpeg \
     libusb-1.0-0-dev speech-dispatcher libgeos-dev portaudio19-dev \
     cmake pkg-config ninja-build \
-    && add-apt-repository -y ppa:deadsnakes/ppa \
-    && apt-get update \
-    && apt-get install -y --no-install-recommends \
-       python${PYTHON_VERSION} \
-       python${PYTHON_VERSION}-venv \
-       python${PYTHON_VERSION}-dev \
+    python${PYTHON_VERSION} \
+    python${PYTHON_VERSION}-venv \
+    python${PYTHON_VERSION}-dev \
     && curl -LsSf https://astral.sh/uv/install.sh | sh \
     && mv /root/.local/bin/uv /usr/local/bin/uv \
     && useradd --create-home --shell /bin/bash user_lerobot \

docs/source/_toctree.yml

@@ -47,6 +47,8 @@
     title: π₀-FAST (Pi0Fast)
   - local: pi05
     title: π₀.₅ (Pi05)
+  - local: eo1
+    title: EO-1
   - local: groot
     title: NVIDIA GR00T N1.5
   - local: xvla

docs/source/eo1.mdx

@@ -0,0 +1,168 @@
+# EO-1
+
+EO-1 is a **Vision-Language-Action policy for robot control**. The LeRobot implementation integrates EO-1 with the standard LeRobot training, evaluation, processor interface.
+
+## Model Overview
+
+EO-1 uses a Qwen2.5-VL backbone for vision-language understanding and adds a continuous flow-matching action head for robot control. The policy formats each robot-control sample as a multimodal conversation: camera images are passed to Qwen2.5-VL, the robot state is represented with EO-1 state tokens, and the future action chunk is represented with EO-1 action tokens.
+
+<img
+  src="https://huggingface.co/datasets/HaomingSong/lerobot-documentation-images/resolve/main/lerobot/eo_pipeline.png"
+  alt="An overview of EO-1"
+  width="85%"
+/>
+
+During training, EO-1 learns to denoise continuous action chunks at the action-token positions. During inference, it samples an action chunk, returns continuous actions, and executes `n_action_steps` from the chunk before sampling again.
+
+### What the LeRobot Integration Covers
+
+- Standard `policy.type=eo1` configuration through LeRobot
+- Qwen2.5-VL image and text preprocessing through policy processors
+- Continuous flow-matching action prediction
+- Checkpoint save/load through LeRobot policy APIs
+- Training with `lerobot-train` and evaluation with `lerobot-eval`
+
+The broader EO-1 project also includes interleaved vision-text-action pretraining and multimodal reasoning workflows. This page focuses on the LeRobot robot-control policy path.
+
+## Installation Requirements
+
+1. Install LeRobot by following the [Installation Guide](./installation).
+2. Install EO-1 dependencies by running:
+
+   ```bash
+   pip install -e ".[eo1]"
+   ```
+
+3. If you want to train or evaluate on LIBERO, install the LIBERO dependencies too:
+
+   ```bash
+   pip install -e ".[eo1,libero]"
+   ```
+
+EO-1 can use the standard PyTorch scaled-dot-product attention backend through `policy.attn_implementation=sdpa`. If your environment has a compatible `flash_attn` installation, you can request `policy.attn_implementation=flash_attention_2`.
+
+## Data Requirements
+
+EO-1 expects a LeRobot dataset with:
+
+- At least one visual observation, for example `observation.images.image`
+- `observation.state`
+- `action`
+- A language task instruction through the dataset `task` field
+
+If your dataset uses different observation names, use `rename_map` to align them with the names expected by your training or evaluation setup.
+
+## Usage
+
+To use EO-1 in a LeRobot configuration, specify the policy type as:
+
+```python
+policy.type=eo1
+```
+
+By default, a new EO-1 policy initializes its backbone from:
+
+```python
+policy.vlm_base=Qwen/Qwen2.5-VL-3B-Instruct
+```
+
+Once a LeRobot-format EO-1 checkpoint is available, load it with:
+
+```python
+policy.path=your-org/your-eo1-checkpoint
+```
+
+## Training
+
+### Training Command Example
+
+```bash
+lerobot-train \
+  --dataset.repo_id=your_org/your_dataset \
+  --policy.type=eo1 \
+  --policy.vlm_base=Qwen/Qwen2.5-VL-3B-Instruct \
+  --policy.dtype=bfloat16 \
+  --policy.attn_implementation=sdpa \
+  --policy.gradient_checkpointing=false \
+  --output_dir=./outputs/eo1_training \
+  --job_name=eo1_training \
+  --steps=300000 \
+  --batch_size=16 \
+  --policy.device=cuda
+```
+
+### Key Training Parameters
+
+| Parameter                              | Default                       | Description                                                             |
+| -------------------------------------- | ----------------------------- | ----------------------------------------------------------------------- |
+| `policy.vlm_base`                      | `Qwen/Qwen2.5-VL-3B-Instruct` | Qwen2.5-VL checkpoint used to initialize a new policy                   |
+| `policy.dtype`                         | `auto`                        | Backbone dtype request: `auto`, `bfloat16`, or `float32`                |
+| `policy.attn_implementation`           | `None`                        | Optional Qwen attention backend, such as `sdpa`                         |
+| `policy.gradient_checkpointing`        | `false`                       | Reduces memory usage during training                                    |
+| `policy.chunk_size`                    | `8`                           | Number of future actions predicted per chunk                            |
+| `policy.n_action_steps`                | `8`                           | Number of actions consumed from a sampled chunk                         |
+| `policy.num_denoise_steps`             | `10`                          | Number of flow-matching denoising steps used during sampling            |
+| `policy.max_state_dim`                 | `32`                          | State padding dimension                                                 |
+| `policy.max_action_dim`                | `32`                          | Action padding dimension                                                |
+| `policy.force_fp32_autocast`           | `true`                        | Keeps the flow head in fp32 even when the backbone uses mixed precision |
+| `policy.supervise_padding_action_dims` | `true`                        | Controls whether padded action dimensions are supervised                |
+| `policy.supervise_padding_actions`     | `true`                        | Controls whether padded future action rows are supervised               |
+
+## Evaluation
+
+EO-1 can be evaluated through `lerobot-eval` once you have a LeRobot-format checkpoint:
+
+```bash
+lerobot-eval \
+  --policy.path=your-org/your-eo1-checkpoint \
+  --env.type=libero \
+  --env.task=libero_object \
+  --eval.batch_size=1 \
+  --eval.n_episodes=20
+```
+
+For datasets or environments whose camera names differ from the checkpoint configuration, pass a `rename_map`:
+
+```bash
+lerobot-eval \
+  --policy.path=your-org/your-eo1-checkpoint \
+  --env.type=libero \
+  --env.task=libero_object \
+  --rename_map='{"observation.images.image2":"observation.images.wrist_image"}'
+```
+
+## Configuration Notes
+
+### Image Processing
+
+EO-1 uses the Qwen2.5-VL processor. The `policy.image_min_pixels` and `policy.image_max_pixels` settings control the image resizing bounds before the visual tokens are passed into the backbone.
+
+### State and Action Dimensions
+
+The policy pads state and action vectors to `policy.max_state_dim` and `policy.max_action_dim` before the EO-1 flow head. Predictions are cropped back to the original action dimension before being returned by the policy.
+
+### Attention Backend
+
+Use `policy.attn_implementation=sdpa` for a portable setup. Use `flash_attention_2` only when `flash_attn` is installed and compatible with your environment.
+
+## References
+
+- [EO-1 project](https://github.com/EO-Robotics/EO1)
+- [EO-1 paper](https://arxiv.org/abs/2508.21112)
+- [Qwen2.5-VL-3B-Instruct](https://huggingface.co/Qwen/Qwen2.5-VL-3B-Instruct)
+
+## Citation
+
+```bibtex
+@article{eo1,
+  title={EO-1: Interleaved Vision-Text-Action Pretraining for General Robot Control},
+  author={Delin Qu and Haoming Song and Qizhi Chen and Zhaoqing Chen and Xianqiang Gao and Xinyi Ye and Qi Lv and Modi Shi and Guanghui Ren and Cheng Ruan and Maoqing Yao and Haoran Yang and Jiacheng Bao and Bin Zhao and Dong Wang},
+  journal={arXiv preprint},
+  year={2025},
+  url={https://arxiv.org/abs/2508.21112}
+}
+```
+
+## License
+
+This LeRobot integration follows the **Apache 2.0 License** used by LeRobot. Check the upstream EO-1 model and dataset pages for the licenses of released EO-1 checkpoints and data.

docs/source/sarm.mdx

@@ -46,7 +46,7 @@ This ensures identical task states map to consistent progress values, even acros
 
 ## Inputs and Targets (What the new code expects)
 
-SARM is trained through its processor (`src/lerobot/policies/sarm/processor_sarm.py`), which:
+SARM is trained through its processor (`src/lerobot/rewards/sarm/processor_sarm.py`), which:
 
 - **Encodes** images and task text with CLIP (ViT-B/32) into `video_features` and `text_features`
 - **Pads/truncates** robot state into `state_features` (up to `max_state_dim`)
@@ -347,7 +347,7 @@ Use `compute_rabc_weights.py` with `--visualize-only` to visualize model predict
 <hfoption id="single_stage">
 
 ```bash
-python src/lerobot/policies/sarm/compute_rabc_weights.py \
+python -m lerobot.rewards.sarm.compute_rabc_weights \
   --dataset-repo-id your-username/your-dataset \
   --reward-model-path your-username/sarm-model \
   --visualize-only \
@@ -360,7 +360,7 @@ python src/lerobot/policies/sarm/compute_rabc_weights.py \
 <hfoption id="dense_only">
 
 ```bash
-python src/lerobot/policies/sarm/compute_rabc_weights.py \
+python -m lerobot.rewards.sarm.compute_rabc_weights \
   --dataset-repo-id your-username/your-dataset \
   --reward-model-path your-username/sarm-model \
   --visualize-only \
@@ -373,7 +373,7 @@ python src/lerobot/policies/sarm/compute_rabc_weights.py \
 <hfoption id="dual">
 
 ```bash
-python src/lerobot/policies/sarm/compute_rabc_weights.py \
+python -m lerobot.rewards.sarm.compute_rabc_weights \
   --dataset-repo-id your-username/your-dataset \
   --reward-model-path your-username/sarm-model \
   --visualize-only \
@@ -429,7 +429,7 @@ The weighting follows **Equations 8-9** from the paper:
 First, run the SARM model on all frames in your dataset to compute progress values:
 
 ```bash
-python src/lerobot/policies/sarm/compute_rabc_weights.py \
+python -m lerobot.rewards.sarm.compute_rabc_weights \
   --dataset-repo-id your-username/your-dataset \
   --reward-model-path your-username/sarm-model \
   --head-mode sparse \
@@ -465,15 +465,15 @@ This script:
 
 ### Step 5b: Train Policy with RA-BC
 
-Once you have the progress file, train your policy with RA-BC weighting. The progress file is auto-detected from the dataset path (`sarm_progress.parquet`). Currently PI0, PI0.5 and SmolVLA are supported with RA-BC:
+Once you have the progress file, train your policy with RA-BC weighting. The progress file is auto-detected from the dataset path (`sarm_progress.parquet`) if not explicitly provided. Currently PI0, PI0.5 and SmolVLA are supported with RA-BC:
 
 ```bash
 lerobot-train \
   --dataset.repo_id=your-username/your-dataset \
   --policy.type=pi0 \
-  --use_rabc=true \
-  --rabc_head_mode=sparse \
-  --rabc_kappa=0.01 \
+  --sample_weighting.type=rabc \
+  --sample_weighting.head_mode=sparse \
+  --sample_weighting.kappa=0.01 \
   --output_dir=outputs/train/policy_rabc \
   --batch_size=32 \
   --steps=40000
@@ -488,12 +488,13 @@ The training script automatically:
 
 **RA-BC Arguments:**
 
-| Argument               | Description                                                | Default                            |
-| ---------------------- | ---------------------------------------------------------- | ---------------------------------- |
-| `--use_rabc`           | Enable RA-BC sample weighting                              | `false`                            |
-| `--rabc_progress_path` | Path to progress parquet file (auto-detected from dataset) | `sarm_progress.parquet` in dataset |
-| `--rabc_head_mode`     | Which SARM head's progress to use: `sparse` or `dense`     | `sparse`                           |
-| `--rabc_kappa`         | Threshold κ for high-quality samples                       | `0.01`                             |
+| Argument                           | Description                                            | Default                 |
+| ---------------------------------- | ------------------------------------------------------ | ----------------------- |
+| `--sample_weighting.type`          | Weighting strategy type (`rabc` or `uniform`)          | `rabc`                  |
+| `--sample_weighting.progress_path` | Path to progress parquet file                          | `sarm_progress.parquet` |
+| `--sample_weighting.head_mode`     | Which SARM head's progress to use: `sparse` or `dense` | `sparse`                |
+| `--sample_weighting.kappa`         | Threshold κ for high-quality samples                   | `0.01`                  |
+| `--sample_weighting.epsilon`       | Small constant for numerical stability                 | `1e-6`                  |
 
 ### Tuning RA-BC Kappa
 
@@ -511,30 +512,30 @@ The `kappa` parameter is the threshold that determines which samples get full we
 
 Monitor these WandB metrics during training:
 
-| Metric             | Healthy Range | Problem Indicator         |
-| ------------------ | ------------- | ------------------------- |
-| `rabc_mean_weight` | 0.3 - 0.8     | ≈ 1.0 means kappa too low |
-| `rabc_delta_mean`  | > 0           | Should be positive        |
-| `rabc_delta_std`   | > 0           | Variance in data quality  |
+| Metric                        | Healthy Range | Problem Indicator         |
+| ----------------------------- | ------------- | ------------------------- |
+| `sample_weight_mean_weight`   | 0.3 - 0.8     | ≈ 1.0 means kappa too low |
+| `sample_weighting/delta_mean` | > 0           | Should be positive        |
+| `sample_weighting/delta_std`  | > 0           | Variance in data quality  |
 
-**If `rabc_mean_weight ≈ 1.0`:** Your kappa is too low. Most samples have `delta > kappa` and bypass the soft-weighting entirely. RA-BC becomes equivalent to vanilla BC.
+**If `sample_weight_mean_weight ≈ 1.0`:** Your kappa is too low. Most samples have `delta > kappa` and bypass the soft-weighting entirely. RA-BC becomes equivalent to vanilla BC.
 
 **Setting kappa based on your data:**
 
-The default `kappa=0.01` was tuned for the paper's T-shirt folding task (~90s episodes at 30fps). For your dataset, check the logged `rabc_delta_mean` and `rabc_delta_std`:
+The default `kappa=0.01` was tuned for the paper's T-shirt folding task (~90s episodes at 30fps). For your dataset, check the logged `sample_weighting/delta_mean` and `sample_weighting/delta_std`:
 
 ```
 # If delta_mean ≈ 0.03 and delta_std ≈ 0.02:
 # Most deltas fall in range [0.01, 0.05]
 
 # Option 1: Set kappa = delta_mean (medium selectivity)
---rabc_kappa=0.03
+--sample_weighting.kappa=0.03
 
 # Option 2: Set kappa = delta_mean + delta_std (high selectivity)
---rabc_kappa=0.05
+--sample_weighting.kappa=0.05
 
 # Option 3: Set kappa = delta_mean + 2*delta_std (very selective)
---rabc_kappa=0.07
+--sample_weighting.kappa=0.07
 ```
 
 **When RA-BC may not help:**
@@ -550,8 +551,8 @@ accelerate launch \
   src/lerobot/scripts/lerobot_train.py \
   --dataset.repo_id=your-username/your-dataset \
   --policy.type=pi0 \
-  --use_rabc=true \
-  --rabc_kappa=0.01 \
+  --sample_weighting.type=rabc \
+  --sample_weighting.kappa=0.01 \
   --output_dir=outputs/train/policy_rabc \
   --batch_size=32 \
   --steps=40000
@@ -576,7 +577,7 @@ accelerate launch \
 ### RA-BC
 
 1. **Train SARM first**: RA-BC quality depends entirely on SARM quality
-2. **Monitor `rabc_mean_weight`**: If it's ≈ 1.0, increase kappa (see [Tuning RA-BC Kappa](#tuning-ra-bc-kappa))
+2. **Monitor `sample_weight_mean_weight`**: If it's ≈ 1.0, increase kappa (see [Tuning RA-BC Kappa](#tuning-ra-bc-kappa))
 
 ---
 

docs/source/xvla.mdx

@@ -220,7 +220,7 @@ REAL_DIM = 12
 # Postprocessing: Trim 20D predictions to 12D for deployment
 ```
 
-See the [action_hub.py](/home/jade_choghari/robot/lerobot/src/lerobot/policies/xvla/action_hub.py) implementation for details.
+See the [action_hub.py](https://github.com/huggingface/lerobot/blob/main/src/lerobot/policies/xvla/action_hub.py) implementation for details.
 
 #### Auto Action Mode (Recommended)
 
@@ -519,9 +519,9 @@ If you use X-VLA in your research, please cite:
 
 - [X-VLA Paper](https://arxiv.org/pdf/2510.10274)
 - [LeRobot Documentation](https://github.com/huggingface/lerobot)
-- [Action Registry Implementation](https://github.com/huggingface/lerobot/src/lerobot/policies/xvla/action_hub.py)
-- [Processor Implementation](https://github.com/huggingface/lerobot/src/lerobot/policies/xvla/processor_xvla.py)
-- [Model Configuration](https://github.com/huggingface/lerobot/src/lerobot/policies/xvla/configuration_xvla.py)
+- [Action Registry Implementation](https://github.com/huggingface/lerobot/blob/main/src/lerobot/policies/xvla/action_hub.py)
+- [Processor Implementation](https://github.com/huggingface/lerobot/blob/main/src/lerobot/policies/xvla/processor_xvla.py)
+- [Model Configuration](https://github.com/huggingface/lerobot/blob/main/src/lerobot/policies/xvla/configuration_xvla.py)
 
 ## Contributing
 

examples/dataset/slurm_compute_rabc.py

@@ -69,7 +69,7 @@ class ComputeProgressShards(PipelineStep):
         import torch
         from tqdm import tqdm
 
-        from lerobot.policies.sarm.compute_rabc_weights import (
+        from lerobot.rewards.sarm.compute_rabc_weights import (
             generate_all_frame_indices,
             interpolate_progress,
             load_sarm_resources,

examples/tutorial/rl/hilserl_example.py

@@ -10,7 +10,7 @@ from lerobot.datasets import LeRobotDataset
 from lerobot.envs.configs import HILSerlProcessorConfig, HILSerlRobotEnvConfig
 from lerobot.policies import SACConfig
 from lerobot.policies.sac.modeling_sac import SACPolicy
-from lerobot.policies.sac.reward_model.modeling_classifier import Classifier
+from lerobot.rewards.classifier.modeling_classifier import Classifier
 from lerobot.rl.buffer import ReplayBuffer
 from lerobot.rl.gym_manipulator import make_robot_env
 from lerobot.robots.so_follower import SO100FollowerConfig

examples/tutorial/rl/reward_classifier_example.py

@@ -1,7 +1,7 @@
 import torch
 
 from lerobot.datasets import LeRobotDataset
-from lerobot.policies import RewardClassifierConfig, make_policy, make_pre_post_processors
+from lerobot.rewards import RewardClassifierConfig, make_reward_model, make_reward_pre_post_processors
 
 
 def main():
@@ -22,10 +22,10 @@ def main():
         model_name="microsoft/resnet-18",
     )
 
-    # Make policy, preprocessor, and optimizer
-    policy = make_policy(config, ds_meta=dataset.meta)
-    optimizer = config.get_optimizer_preset().build(policy.parameters())
-    preprocessor, _ = make_pre_post_processors(policy_cfg=config, dataset_stats=dataset.meta.stats)
+    # Make reward model, preprocessor, and optimizer
+    reward_model = make_reward_model(config, dataset_stats=dataset.meta.stats)
+    optimizer = config.get_optimizer_preset().build(reward_model.parameters())
+    preprocessor, _ = make_reward_pre_post_processors(config, dataset_stats=dataset.meta.stats)
 
     classifier_id = "<user>/reward_classifier_hil_serl_example"
 
@@ -42,7 +42,7 @@ def main():
             batch = preprocessor(batch)
 
             # Forward pass
-            loss, output_dict = policy.forward(batch)
+            loss, output_dict = reward_model.forward(batch)
 
             # Backward pass and optimization
             optimizer.zero_grad()
@@ -58,8 +58,8 @@ def main():
 
     print("Training finished!")
 
-    # You can now save the trained policy.
-    policy.push_to_hub(classifier_id)
+    # You can now save the trained reward model.
+    reward_model.push_to_hub(classifier_id)
 
 
 if __name__ == "__main__":

pyproject.toml

@@ -128,7 +128,7 @@ dataset_viz = ["lerobot[dataset]", "lerobot[viz]"]
 av-dep = ["av>=15.0.0,<16.0.0"]
 pygame-dep = ["pygame>=2.5.1,<2.7.0"]
 placo-dep = ["placo>=0.9.6,<0.9.17"]
-transformers-dep = ["transformers==5.3.0"] # TODO(Steven): https://github.com/huggingface/lerobot/pull/3249
+transformers-dep = ["transformers>=5.4.0,<5.6.0"]
 grpcio-dep = ["grpcio==1.73.1", "protobuf>=6.31.1,<6.32.0"]
 can-dep = ["python-can>=4.2.0,<5.0.0"]
 peft-dep = ["peft>=0.18.0,<1.0.0"]
@@ -194,6 +194,7 @@ groot = [
 ]
 sarm = ["lerobot[transformers-dep]", "pydantic>=2.0.0,<3.0.0", "faker>=33.0.0,<35.0.0", "lerobot[matplotlib-dep]", "lerobot[qwen-vl-utils-dep]"]
 xvla = ["lerobot[transformers-dep]"]
+eo1 = ["lerobot[transformers-dep]", "lerobot[qwen-vl-utils-dep]"]
 hilserl = ["lerobot[transformers-dep]", "gym-hil>=0.1.13,<0.2.0", "lerobot[grpcio-dep]", "lerobot[placo-dep]"]
 
 # Features

src/lerobot/cameras/realsense/camera_realsense.py

@@ -17,6 +17,7 @@ Provides the RealSenseCamera class for capturing frames from Intel RealSense cam
 """
 
 import logging
+import sys
 import time
 from threading import Event, Lock, Thread
 from typing import TYPE_CHECKING, Any
@@ -41,6 +42,7 @@ from ..utils import get_cv2_rotation
 from .configuration_realsense import RealSenseCameraConfig
 
 logger = logging.getLogger(__name__)
+pkg_name = "pyrealsense2-macosx" if sys.platform == "darwin" else "pyrealsense2"
 
 
 class RealSenseCamera(Camera):
@@ -114,7 +116,7 @@ class RealSenseCamera(Camera):
         Args:
             config: The configuration settings for the camera.
         """
-        require_package("pyrealsense2", extra="intelrealsense")
+        require_package(pkg_name, extra="intelrealsense", import_name="pyrealsense2")
         super().__init__(config)
 
         self.config = config

src/lerobot/common/wandb_utils.py

@@ -41,8 +41,12 @@ def cfg_to_group(
             return tag
         return tag[:max_tag_length]
 
+    if cfg.is_reward_model_training:
+        trainable_tag = f"reward_model:{cfg.reward_model.type}"
+    else:
+        trainable_tag = f"policy:{cfg.policy.type}"
     lst = [
-        f"policy:{cfg.policy.type}",
+        trainable_tag,
         f"seed:{cfg.seed}",
     ]
     if cfg.dataset is not None:

src/lerobot/configs/rewards.py

@@ -0,0 +1,163 @@
+# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import abc
+import builtins
+import json
+import logging
+import os
+import tempfile
+from dataclasses import dataclass, field
+from pathlib import Path
+from typing import Any, TypeVar
+
+import draccus
+from huggingface_hub import hf_hub_download
+from huggingface_hub.constants import CONFIG_NAME
+from huggingface_hub.errors import HfHubHTTPError
+
+from lerobot.configs.types import PolicyFeature
+from lerobot.optim.optimizers import OptimizerConfig
+from lerobot.optim.schedulers import LRSchedulerConfig
+from lerobot.utils.device_utils import auto_select_torch_device, is_torch_device_available
+from lerobot.utils.hub import HubMixin
+
+T = TypeVar("T", bound="RewardModelConfig")
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class RewardModelConfig(draccus.ChoiceRegistry, HubMixin, abc.ABC):
+    """Base configuration for reward models.
+
+    Args:
+    input_features: A dictionary defining the PolicyFeature of the input data for the reward. The key represents
+        the input data name, and the value is PolicyFeature, which consists of FeatureType and shape attributes.
+    output_features: A dictionary defining the PolicyFeature of the output data for the reward. The key represents
+        the output data name, and the value is PolicyFeature, which consists of FeatureType and shape attributes.
+    """
+
+    # Reuses PolicyFeature
+    input_features: dict[str, PolicyFeature] = field(default_factory=dict)
+    output_features: dict[str, PolicyFeature] = field(default_factory=dict)
+
+    device: str | None = None
+
+    pretrained_path: str | None = None
+
+    push_to_hub: bool = False
+    repo_id: str | None = None
+
+    # Hub metadata
+    license: str | None = None
+    tags: list[str] | None = None
+    private: bool | None = None
+
+    def __post_init__(self) -> None:
+        if not self.device or not is_torch_device_available(self.device):
+            auto_device = auto_select_torch_device()
+            logger.warning(f"Device '{self.device}' is not available. Switching to '{auto_device}'.")
+            self.device = auto_device.type
+
+    @property
+    def type(self) -> str:
+        choice_name = self.get_choice_name(self.__class__)
+        if not isinstance(choice_name, str):
+            raise TypeError(f"Expected string from get_choice_name, got {type(choice_name)}")
+        return choice_name
+
+    @property
+    def observation_delta_indices(self) -> list | None:  # type: ignore[type-arg]
+        return None
+
+    @property
+    def action_delta_indices(self) -> list | None:  # type: ignore[type-arg]
+        return None
+
+    @property
+    def reward_delta_indices(self) -> list | None:  # type: ignore[type-arg]
+        return None
+
+    @abc.abstractmethod
+    def get_optimizer_preset(self) -> OptimizerConfig:
+        raise NotImplementedError
+
+    def get_scheduler_preset(self) -> LRSchedulerConfig | None:
+        return None
+
+    def validate_features(self) -> None:
+        pass
+
+    def _save_pretrained(self, save_directory: Path) -> None:
+        with open(save_directory / CONFIG_NAME, "w") as f, draccus.config_type("json"):
+            draccus.dump(self, f, indent=4)
+
+    @classmethod
+    def from_pretrained(
+        cls: builtins.type[T],
+        pretrained_name_or_path: str | Path,
+        *,
+        force_download: bool = False,
+        resume_download: bool | None = None,
+        proxies: dict[Any, Any] | None = None,
+        token: str | bool | None = None,
+        cache_dir: str | Path | None = None,
+        local_files_only: bool = False,
+        revision: str | None = None,
+        **reward_kwargs: Any,
+    ) -> T:
+        model_id = str(pretrained_name_or_path)
+        config_file: str | None = None
+        if Path(model_id).is_dir():
+            if CONFIG_NAME in os.listdir(model_id):
+                config_file = os.path.join(model_id, CONFIG_NAME)
+            else:
+                logger.error(f"{CONFIG_NAME} not found in {Path(model_id).resolve()}")
+        else:
+            try:
+                config_file = hf_hub_download(
+                    repo_id=model_id,
+                    filename=CONFIG_NAME,
+                    revision=revision,
+                    cache_dir=cache_dir,
+                    force_download=force_download,
+                    proxies=proxies,
+                    resume_download=resume_download,
+                    token=token,
+                    local_files_only=local_files_only,
+                )
+            except HfHubHTTPError as e:
+                raise FileNotFoundError(
+                    f"{CONFIG_NAME} not found on the HuggingFace Hub in {model_id}"
+                ) from e
+
+        if config_file is None:
+            raise FileNotFoundError(f"{CONFIG_NAME} not found in {model_id}")
+
+        # HACK: Parse the original config to get the config subclass, so that we can
+        # apply cli overrides.
+        with draccus.config_type("json"):
+            orig_config = draccus.parse(cls, config_file, args=[])
+
+        with open(config_file) as f:
+            config = json.load(f)
+
+        config.pop("type", None)
+        with tempfile.NamedTemporaryFile("w+", delete=False, suffix=".json") as f:
+            json.dump(config, f)
+            config_file = f.name
+
+        cli_overrides = reward_kwargs.pop("cli_overrides", [])
+        with draccus.config_type("json"):
+            return draccus.parse(orig_config.__class__, config_file, args=cli_overrides)

src/lerobot/configs/train.py

@@ -13,7 +13,9 @@
 # limitations under the License.
 import builtins
 import datetime as dt
+import json
 import os
+import tempfile
 from dataclasses import dataclass, field
 from pathlib import Path
 from typing import Any
@@ -26,18 +28,57 @@ from lerobot import envs
 from lerobot.configs import parser
 from lerobot.optim import LRSchedulerConfig, OptimizerConfig
 from lerobot.utils.hub import HubMixin
+from lerobot.utils.sample_weighting import SampleWeightingConfig
 
 from .default import DatasetConfig, EvalConfig, PeftConfig, WandBConfig
 from .policies import PreTrainedConfig
+from .rewards import RewardModelConfig
 
 TRAIN_CONFIG_NAME = "train_config.json"
 
 
+def _migrate_legacy_rabc_fields(config: dict[str, Any]) -> dict[str, Any] | None:
+    """Return migrated payload for legacy RA-BC fields, or None when no migration is needed."""
+    legacy_fields = (
+        "use_rabc",
+        "rabc_progress_path",
+        "rabc_kappa",
+        "rabc_epsilon",
+        "rabc_head_mode",
+    )
+    if not any(key in config for key in legacy_fields):
+        return None
+
+    migrated_config = dict(config)
+    use_rabc = bool(migrated_config.pop("use_rabc", False))
+    rabc_progress_path = migrated_config.pop("rabc_progress_path", None)
+    rabc_kappa = migrated_config.pop("rabc_kappa", None)
+    rabc_epsilon = migrated_config.pop("rabc_epsilon", None)
+    rabc_head_mode = migrated_config.pop("rabc_head_mode", None)
+
+    # New configs may already define sample_weighting explicitly. In that case,
+    # legacy fields are ignored after being stripped from the payload.
+    if migrated_config.get("sample_weighting") is None and use_rabc:
+        sample_weighting: dict[str, Any] = {"type": "rabc"}
+        if rabc_progress_path is not None:
+            sample_weighting["progress_path"] = rabc_progress_path
+        if rabc_kappa is not None:
+            sample_weighting["kappa"] = rabc_kappa
+        if rabc_epsilon is not None:
+            sample_weighting["epsilon"] = rabc_epsilon
+        if rabc_head_mode is not None:
+            sample_weighting["head_mode"] = rabc_head_mode
+        migrated_config["sample_weighting"] = sample_weighting
+
+    return migrated_config
+
+
 @dataclass
 class TrainPipelineConfig(HubMixin):
     dataset: DatasetConfig
     env: envs.EnvConfig | None = None
     policy: PreTrainedConfig | None = None
+    reward_model: RewardModelConfig | None = None
     # Set `dir` to where you would like to save all of the run outputs. If you run another training session
     # with the same value for `dir` its contents will be overwritten unless you set `resume` to true.
     output_dir: Path | None = None
@@ -72,27 +113,41 @@ class TrainPipelineConfig(HubMixin):
     wandb: WandBConfig = field(default_factory=WandBConfig)
     peft: PeftConfig | None = None
 
-    # RA-BC (Reward-Aligned Behavior Cloning) parameters
-    use_rabc: bool = False  # Enable reward-weighted training
-    rabc_progress_path: str | None = None  # Path to precomputed SARM progress parquet file
-    rabc_kappa: float = 0.01  # Hard threshold for high-quality samples
-    rabc_epsilon: float = 1e-6  # Small constant for numerical stability
-    rabc_head_mode: str | None = "sparse"  # For dual-head models: "sparse" or "dense"
+    # Sample weighting configuration (e.g., for RA-BC training)
+    sample_weighting: SampleWeightingConfig | None = None
 
     # Rename map for the observation to override the image and state keys
     rename_map: dict[str, str] = field(default_factory=dict)
     checkpoint_path: Path | None = field(init=False, default=None)
 
+    @property
+    def is_reward_model_training(self) -> bool:
+        """True when the config targets a reward model rather than a policy."""
+        return self.reward_model is not None
+
+    @property
+    def trainable_config(self) -> PreTrainedConfig | RewardModelConfig:
+        """Return whichever config (policy or reward_model) is active."""
+        if self.is_reward_model_training:
+            return self.reward_model  # type: ignore[return-value]
+        return self.policy  # type: ignore[return-value]
+
     def validate(self) -> None:
         # HACK: We parse again the cli args here to get the pretrained paths if there was some.
         policy_path = parser.get_path_arg("policy")
-        if policy_path:
-            # Only load the policy config
+        reward_model_path = parser.get_path_arg("reward_model")
+
+        if reward_model_path:
+            cli_overrides = parser.get_cli_overrides("reward_model")
+            self.reward_model = RewardModelConfig.from_pretrained(
+                reward_model_path, cli_overrides=cli_overrides
+            )
+            self.reward_model.pretrained_path = str(Path(reward_model_path))
+        elif policy_path:
             cli_overrides = parser.get_cli_overrides("policy")
             self.policy = PreTrainedConfig.from_pretrained(policy_path, cli_overrides=cli_overrides)
             self.policy.pretrained_path = Path(policy_path)
         elif self.resume:
-            # The entire train config is already loaded, we just need to get the checkpoint dir
             config_path = parser.parse_arg("config_path")
             if not config_path:
                 raise ValueError(
@@ -108,18 +163,22 @@ class TrainPipelineConfig(HubMixin):
             policy_dir = Path(config_path).parent
             if self.policy is not None:
                 self.policy.pretrained_path = policy_dir
+            if self.reward_model is not None:
+                self.reward_model.pretrained_path = str(policy_dir)
             self.checkpoint_path = policy_dir.parent
 
-        if self.policy is None:
+        if self.policy is None and self.reward_model is None:
             raise ValueError(
-                "Policy is not configured. Please specify a pretrained policy with `--policy.path`."
+                "Neither policy nor reward_model is configured. "
+                "Please specify one with `--policy.path` or `--reward_model.path`."
             )
 
+        active_cfg = self.trainable_config
         if not self.job_name:
             if self.env is None:
-                self.job_name = f"{self.policy.type}"
+                self.job_name = f"{active_cfg.type}"
             else:
-                self.job_name = f"{self.env.type}_{self.policy.type}"
+                self.job_name = f"{self.env.type}_{active_cfg.type}"
 
         if not self.resume and isinstance(self.output_dir, Path) and self.output_dir.is_dir():
             raise FileExistsError(
@@ -137,26 +196,16 @@ class TrainPipelineConfig(HubMixin):
         if not self.use_policy_training_preset and (self.optimizer is None or self.scheduler is None):
             raise ValueError("Optimizer and Scheduler must be set when the policy presets are not used.")
         elif self.use_policy_training_preset and not self.resume:
-            self.optimizer = self.policy.get_optimizer_preset()
-            self.scheduler = self.policy.get_scheduler_preset()
+            self.optimizer = active_cfg.get_optimizer_preset()
+            self.scheduler = active_cfg.get_scheduler_preset()
 
-        if self.policy.push_to_hub and not self.policy.repo_id:
-            raise ValueError(
-                "'policy.repo_id' argument missing. Please specify it to push the model to the hub."
-            )
-
-        if self.use_rabc and not self.rabc_progress_path:
-            # Auto-detect from dataset path
-            repo_id = self.dataset.repo_id
-            if self.dataset.root:
-                self.rabc_progress_path = str(Path(self.dataset.root) / "sarm_progress.parquet")
-            else:
-                self.rabc_progress_path = f"hf://datasets/{repo_id}/sarm_progress.parquet"
+        if hasattr(active_cfg, "push_to_hub") and active_cfg.push_to_hub and not active_cfg.repo_id:
+            raise ValueError("'repo_id' argument missing. Please specify it to push the model to the hub.")
 
     @classmethod
     def __get_path_fields__(cls) -> list[str]:
-        """This enables the parser to load config from the policy using `--policy.path=local/dir`"""
-        return ["policy"]
+        """Keys for draccus pretrained-path loading."""
+        return ["policy", "reward_model"]
 
     def to_dict(self) -> dict[str, Any]:
         return draccus.encode(self)  # type: ignore[no-any-return]  # because of the third-party library draccus uses Any as the return type
@@ -207,6 +256,15 @@ class TrainPipelineConfig(HubMixin):
                 ) from e
 
         cli_args = kwargs.pop("cli_args", [])
+        if config_file is not None:
+            with open(config_file) as f:
+                config = json.load(f)
+            migrated_config = _migrate_legacy_rabc_fields(config)
+            if migrated_config is not None:
+                with tempfile.NamedTemporaryFile("w+", delete=False, suffix=".json") as f:
+                    json.dump(migrated_config, f)
+                    config_file = f.name
+
         with draccus.config_type("json"):
             return draccus.parse(cls, config_file, args=cli_args)
 

src/lerobot/datasets/aggregate.py

@@ -97,8 +97,8 @@ def update_data_df(df, src_meta, dst_meta):
         pd.DataFrame: Updated DataFrame with adjusted indices.
     """
 
-    df["episode_index"] = df["episode_index"] + dst_meta.info["total_episodes"]
-    df["index"] = df["index"] + dst_meta.info["total_frames"]
+    df["episode_index"] = df["episode_index"] + dst_meta.info.total_episodes
+    df["index"] = df["index"] + dst_meta.info.total_frames
 
     src_task_names = src_meta.tasks.index.take(df["task_index"].to_numpy())
     df["task_index"] = dst_meta.tasks.loc[src_task_names, "task_index"].to_numpy()
@@ -225,9 +225,9 @@ def update_meta_data(
         # Clean up temporary columns
         df = df.drop(columns=["_orig_chunk", "_orig_file"])
 
-    df["dataset_from_index"] = df["dataset_from_index"] + dst_meta.info["total_frames"]
-    df["dataset_to_index"] = df["dataset_to_index"] + dst_meta.info["total_frames"]
-    df["episode_index"] = df["episode_index"] + dst_meta.info["total_episodes"]
+    df["dataset_from_index"] = df["dataset_from_index"] + dst_meta.info.total_frames
+    df["dataset_to_index"] = df["dataset_to_index"] + dst_meta.info.total_frames
+    df["episode_index"] = df["episode_index"] + dst_meta.info.total_episodes
 
     return df
 
@@ -237,8 +237,8 @@ def aggregate_datasets(
     aggr_repo_id: str,
     roots: list[Path] | None = None,
     aggr_root: Path | None = None,
-    data_files_size_in_mb: float | None = None,
-    video_files_size_in_mb: float | None = None,
+    data_files_size_in_mb: int | None = None,
+    video_files_size_in_mb: int | None = None,
     chunk_size: int | None = None,
 ):
     """Aggregates multiple LeRobot datasets into a single unified dataset.
@@ -313,8 +313,8 @@ def aggregate_datasets(
         # to avoid interference between different source datasets
         data_idx.pop("src_to_dst", None)
 
-        dst_meta.info["total_episodes"] += src_meta.total_episodes
-        dst_meta.info["total_frames"] += src_meta.total_frames
+        dst_meta.info.total_episodes += src_meta.total_episodes
+        dst_meta.info.total_frames += src_meta.total_frames
 
     finalize_aggregation(dst_meta, all_metadata)
     logging.info("Aggregation complete.")
@@ -640,14 +640,10 @@ def finalize_aggregation(aggr_meta, all_metadata):
     write_tasks(aggr_meta.tasks, aggr_meta.root)
 
     logging.info("write info")
-    aggr_meta.info.update(
-        {
-            "total_tasks": len(aggr_meta.tasks),
-            "total_episodes": sum(m.total_episodes for m in all_metadata),
-            "total_frames": sum(m.total_frames for m in all_metadata),
-            "splits": {"train": f"0:{sum(m.total_episodes for m in all_metadata)}"},
-        }
-    )
+    aggr_meta.info.total_tasks = len(aggr_meta.tasks)
+    aggr_meta.info.total_episodes = sum(m.total_episodes for m in all_metadata)
+    aggr_meta.info.total_frames = sum(m.total_frames for m in all_metadata)
+    aggr_meta.info.splits = {"train": f"0:{sum(m.total_episodes for m in all_metadata)}"}
     write_info(aggr_meta.info, aggr_meta.root)
 
     logging.info("write stats")

src/lerobot/datasets/dataset_metadata.py

@@ -37,13 +37,11 @@ from .io_utils import (
     load_subtasks,
     load_tasks,
     write_info,
-    write_json,
     write_stats,
     write_tasks,
 )
 from .utils import (
     DEFAULT_EPISODES_PATH,
-    INFO_PATH,
     check_version_compatibility,
     get_safe_version,
     has_legacy_hub_download_metadata,
@@ -228,7 +226,7 @@ class LeRobotDatasetMetadata:
     @property
     def _version(self) -> packaging.version.Version:
         """Codebase version used to create this dataset."""
-        return packaging.version.parse(self.info["codebase_version"])
+        return packaging.version.parse(self.info.codebase_version)
 
     def get_data_file_path(self, ep_index: int) -> Path:
         """Return the relative parquet file path for the given episode index.
@@ -283,27 +281,27 @@ class LeRobotDatasetMetadata:
     @property
     def data_path(self) -> str:
         """Formattable string for the parquet files."""
-        return self.info["data_path"]
+        return self.info.data_path
 
     @property
     def video_path(self) -> str | None:
         """Formattable string for the video files."""
-        return self.info["video_path"]
+        return self.info.video_path
 
     @property
     def robot_type(self) -> str | None:
         """Robot type used in recording this dataset."""
-        return self.info["robot_type"]
+        return self.info.robot_type
 
     @property
     def fps(self) -> int:
         """Frames per second used during data collection."""
-        return self.info["fps"]
+        return self.info.fps
 
     @property
     def features(self) -> dict[str, dict]:
         """All features contained in the dataset."""
-        return self.info["features"]
+        return self.info.features
 
     @property
     def image_keys(self) -> list[str]:
@@ -333,32 +331,32 @@ class LeRobotDatasetMetadata:
     @property
     def total_episodes(self) -> int:
         """Total number of episodes available."""
-        return self.info["total_episodes"]
+        return self.info.total_episodes
 
     @property
     def total_frames(self) -> int:
         """Total number of frames saved in this dataset."""
-        return self.info["total_frames"]
+        return self.info.total_frames
 
     @property
     def total_tasks(self) -> int:
         """Total number of different tasks performed in this dataset."""
-        return self.info["total_tasks"]
+        return self.info.total_tasks
 
     @property
     def chunks_size(self) -> int:
         """Max number of files per chunk."""
-        return self.info["chunks_size"]
+        return self.info.chunks_size
 
     @property
     def data_files_size_in_mb(self) -> int:
         """Max size of data file in mega bytes."""
-        return self.info["data_files_size_in_mb"]
+        return self.info.data_files_size_in_mb
 
     @property
     def video_files_size_in_mb(self) -> int:
         """Max size of video file in mega bytes."""
-        return self.info["video_files_size_in_mb"]
+        return self.info.video_files_size_in_mb
 
     def get_task_index(self, task: str) -> int | None:
         """
@@ -502,10 +500,10 @@ class LeRobotDatasetMetadata:
         self._save_episode_metadata(episode_dict)
 
         # Update info
-        self.info["total_episodes"] += 1
-        self.info["total_frames"] += episode_length
-        self.info["total_tasks"] = len(self.tasks)
-        self.info["splits"] = {"train": f"0:{self.info['total_episodes']}"}
+        self.info.total_episodes += 1
+        self.info.total_frames += episode_length
+        self.info.total_tasks = len(self.tasks)
+        self.info.splits = {"train": f"0:{self.info.total_episodes}"}
 
         write_info(self.info, self.root)
 
@@ -524,7 +522,7 @@ class LeRobotDatasetMetadata:
         for key in video_keys:
             if not self.features[key].get("info", None):
                 video_path = self.root / self.video_path.format(video_key=key, chunk_index=0, file_index=0)
-                self.info["features"][key]["info"] = get_video_info(video_path)
+                self.info.features[key]["info"] = get_video_info(video_path)
 
     def update_chunk_settings(
         self,
@@ -546,17 +544,17 @@ class LeRobotDatasetMetadata:
         if chunks_size is not None:
             if chunks_size <= 0:
                 raise ValueError(f"chunks_size must be positive, got {chunks_size}")
-            self.info["chunks_size"] = chunks_size
+            self.info.chunks_size = chunks_size
 
         if data_files_size_in_mb is not None:
             if data_files_size_in_mb <= 0:
                 raise ValueError(f"data_files_size_in_mb must be positive, got {data_files_size_in_mb}")
-            self.info["data_files_size_in_mb"] = data_files_size_in_mb
+            self.info.data_files_size_in_mb = data_files_size_in_mb
 
         if video_files_size_in_mb is not None:
             if video_files_size_in_mb <= 0:
                 raise ValueError(f"video_files_size_in_mb must be positive, got {video_files_size_in_mb}")
-            self.info["video_files_size_in_mb"] = video_files_size_in_mb
+            self.info.video_files_size_in_mb = video_files_size_in_mb
 
         # Update the info file on disk
         write_info(self.info, self.root)
@@ -653,7 +651,7 @@ class LeRobotDatasetMetadata:
                 f"Features contain video keys {obj.video_keys}, but 'use_videos' is set to False. "
                 "Either remove video features from the features dict, or set 'use_videos=True'."
             )
-        write_json(obj.info, obj.root / INFO_PATH)
+        write_info(obj.info, obj.root)
         obj.revision = None
         obj._pq_writer = None
         obj.latest_episode = None

src/lerobot/datasets/dataset_tools.py

@@ -897,14 +897,10 @@ def _copy_and_reindex_episodes_metadata(
 
     dst_meta.finalize()
 
-    dst_meta.info.update(
-        {
-            "total_episodes": len(episode_mapping),
-            "total_frames": total_frames,
-            "total_tasks": len(dst_meta.tasks) if dst_meta.tasks is not None else 0,
-            "splits": {"train": f"0:{len(episode_mapping)}"},
-        }
-    )
+    dst_meta.info.total_episodes = len(episode_mapping)
+    dst_meta.info.total_frames = total_frames
+    dst_meta.info.total_tasks = len(dst_meta.tasks) if dst_meta.tasks is not None else 0
+    dst_meta.info.splits = {"train": f"0:{len(episode_mapping)}"}
     write_info(dst_meta.info, dst_meta.root)
 
     if not all_stats:
@@ -1069,21 +1065,20 @@ def _copy_episodes_metadata_and_stats(
     if episodes_dir.exists():
         shutil.copytree(episodes_dir, dst_episodes_dir, dirs_exist_ok=True)
 
-    dst_meta.info.update(
-        {
-            "total_episodes": src_dataset.meta.total_episodes,
-            "total_frames": src_dataset.meta.total_frames,
-            "total_tasks": src_dataset.meta.total_tasks,
-            "splits": src_dataset.meta.info.get("splits", {"train": f"0:{src_dataset.meta.total_episodes}"}),
-        }
+    dst_meta.info.total_episodes = src_dataset.meta.total_episodes
+    dst_meta.info.total_frames = src_dataset.meta.total_frames
+    dst_meta.info.total_tasks = src_dataset.meta.total_tasks
+    # Preserve original splits if available, otherwise create default
+    dst_meta.info.splits = (
+        src_dataset.meta.info.splits
+        if src_dataset.meta.info.splits
+        else {"train": f"0:{src_dataset.meta.total_episodes}"}
     )
 
     if dst_meta.video_keys and src_dataset.meta.video_keys:
         for key in dst_meta.video_keys:
             if key in src_dataset.meta.features:
-                dst_meta.info["features"][key]["info"] = src_dataset.meta.info["features"][key].get(
-                    "info", {}
-                )
+                dst_meta.info.features[key]["info"] = src_dataset.meta.info.features[key].get("info", {})
 
     write_info(dst_meta.info, dst_meta.root)
 
@@ -1525,7 +1520,7 @@ def modify_tasks(
     write_tasks(new_task_df, root)
 
     # Update info.json
-    dataset.meta.info["total_tasks"] = len(unique_tasks)
+    dataset.meta.info.total_tasks = len(unique_tasks)
     write_info(dataset.meta.info, root)
 
     # Reload metadata to reflect changes
@@ -1858,10 +1853,10 @@ def convert_image_to_video_dataset(
         episodes_df.to_parquet(episodes_path, index=False)
 
         # Update metadata info
-        new_meta.info["total_episodes"] = len(episode_indices)
-        new_meta.info["total_frames"] = sum(ep["length"] for ep in all_episode_metadata.values())
-        new_meta.info["total_tasks"] = dataset.meta.total_tasks
-        new_meta.info["splits"] = {"train": f"0:{len(episode_indices)}"}
+        new_meta.info.total_episodes = len(episode_indices)
+        new_meta.info.total_frames = sum(ep["length"] for ep in all_episode_metadata.values())
+        new_meta.info.total_tasks = dataset.meta.total_tasks
+        new_meta.info.splits = {"train": f"0:{len(episode_indices)}"}
 
         # Update video info for all image keys (now videos)
         # We need to manually set video info since update_video_info() checks video_keys first
@@ -1870,7 +1865,7 @@ def convert_image_to_video_dataset(
                 video_path = new_meta.root / new_meta.video_path.format(
                     video_key=img_key, chunk_index=0, file_index=0
                 )
-                new_meta.info["features"][img_key]["info"] = get_video_info(video_path)
+                new_meta.info.features[img_key]["info"] = get_video_info(video_path)
 
         write_info(new_meta.info, new_meta.root)
 

src/lerobot/datasets/factory.py

@@ -19,6 +19,7 @@ from pprint import pformat
 import torch
 
 from lerobot.configs import PreTrainedConfig
+from lerobot.configs.rewards import RewardModelConfig
 from lerobot.configs.train import TrainPipelineConfig
 from lerobot.transforms import ImageTransforms
 from lerobot.utils.constants import ACTION, IMAGENET_STATS, OBS_PREFIX, REWARD
@@ -30,12 +31,14 @@ from .streaming_dataset import StreamingLeRobotDataset
 
 
 def resolve_delta_timestamps(
-    cfg: PreTrainedConfig, ds_meta: LeRobotDatasetMetadata
+    cfg: PreTrainedConfig | RewardModelConfig, ds_meta: LeRobotDatasetMetadata
 ) -> dict[str, list] | None:
-    """Resolves delta_timestamps by reading from the 'delta_indices' properties of the PreTrainedConfig.
+    """Resolves delta_timestamps by reading from the 'delta_indices' properties of the config.
 
     Args:
-        cfg (PreTrainedConfig): The PreTrainedConfig to read delta_indices from.
+        cfg (PreTrainedConfig | RewardModelConfig): The config to read delta_indices from. Both
+            ``PreTrainedConfig`` and concrete ``RewardModelConfig`` subclasses expose the
+            ``{observation,action,reward}_delta_indices`` properties used below.
         ds_meta (LeRobotDatasetMetadata): The dataset from which features and fps are used to build
             delta_timestamps against.
 
@@ -82,7 +85,7 @@ def make_dataset(cfg: TrainPipelineConfig) -> LeRobotDataset | MultiLeRobotDatas
         ds_meta = LeRobotDatasetMetadata(
             cfg.dataset.repo_id, root=cfg.dataset.root, revision=cfg.dataset.revision
         )
-        delta_timestamps = resolve_delta_timestamps(cfg.policy, ds_meta)
+        delta_timestamps = resolve_delta_timestamps(cfg.trainable_config, ds_meta)
         if not cfg.dataset.streaming:
             dataset = LeRobotDataset(
                 cfg.dataset.repo_id,

src/lerobot/datasets/feature_utils.py

@@ -28,6 +28,7 @@ from .utils import (
     DEFAULT_DATA_PATH,
     DEFAULT_VIDEO_FILE_SIZE_IN_MB,
     DEFAULT_VIDEO_PATH,
+    DatasetInfo,
 )
 
 
@@ -78,8 +79,8 @@ def create_empty_dataset_info(
     chunks_size: int | None = None,
     data_files_size_in_mb: int | None = None,
     video_files_size_in_mb: int | None = None,
-) -> dict:
-    """Create a template dictionary for a new dataset's `info.json`.
+) -> DatasetInfo:
+    """Create a template ``DatasetInfo`` object for a new dataset's ``meta/info.json``.
 
     Args:
         codebase_version (str): The version of the LeRobot codebase.
@@ -87,25 +88,24 @@ def create_empty_dataset_info(
         features (dict): The LeRobot features dictionary for the dataset.
         use_videos (bool): Whether the dataset will store videos.
         robot_type (str | None): The type of robot used, if any.
+        chunks_size (int | None): Max files per chunk directory. Defaults to ``DEFAULT_CHUNK_SIZE``.
+        data_files_size_in_mb (int | None): Max parquet file size in MB. Defaults to ``DEFAULT_DATA_FILE_SIZE_IN_MB``.
+        video_files_size_in_mb (int | None): Max video file size in MB. Defaults to ``DEFAULT_VIDEO_FILE_SIZE_IN_MB``.
 
     Returns:
-        dict: A dictionary with the initial dataset metadata.
+        DatasetInfo: A typed dataset information object with initial metadata.
     """
-    return {
-        "codebase_version": codebase_version,
-        "robot_type": robot_type,
-        "total_episodes": 0,
-        "total_frames": 0,
-        "total_tasks": 0,
-        "chunks_size": chunks_size or DEFAULT_CHUNK_SIZE,
-        "data_files_size_in_mb": data_files_size_in_mb or DEFAULT_DATA_FILE_SIZE_IN_MB,
-        "video_files_size_in_mb": video_files_size_in_mb or DEFAULT_VIDEO_FILE_SIZE_IN_MB,
-        "fps": fps,
-        "splits": {},
-        "data_path": DEFAULT_DATA_PATH,
-        "video_path": DEFAULT_VIDEO_PATH if use_videos else None,
-        "features": features,
-    }
+    return DatasetInfo(
+        codebase_version=codebase_version,
+        fps=fps,
+        features=features,
+        robot_type=robot_type,
+        chunks_size=chunks_size or DEFAULT_CHUNK_SIZE,
+        data_files_size_in_mb=data_files_size_in_mb or DEFAULT_DATA_FILE_SIZE_IN_MB,
+        video_files_size_in_mb=video_files_size_in_mb or DEFAULT_VIDEO_FILE_SIZE_IN_MB,
+        data_path=DEFAULT_DATA_PATH,
+        video_path=DEFAULT_VIDEO_PATH if use_videos else None,
+    )
 
 
 def check_delta_timestamps(

src/lerobot/datasets/io_utils.py

@@ -39,6 +39,7 @@ from .utils import (
     EPISODES_DIR,
     INFO_PATH,
     STATS_PATH,
+    DatasetInfo,
     serialize_dict,
 )
 
@@ -115,25 +116,21 @@ def embed_images(dataset: datasets.Dataset) -> datasets.Dataset:
     return dataset
 
 
-def write_info(info: dict, local_dir: Path) -> None:
-    write_json(info, local_dir / INFO_PATH)
+def write_info(info: DatasetInfo, local_dir: Path) -> None:
+    write_json(info.to_dict(), local_dir / INFO_PATH)
 
 
-def load_info(local_dir: Path) -> dict:
+def load_info(local_dir: Path) -> DatasetInfo:
     """Load dataset info metadata from its standard file path.
 
-    Also converts shape lists to tuples for consistency.
-
     Args:
         local_dir (Path): The root directory of the dataset.
 
     Returns:
-        dict: The dataset information dictionary.
+        DatasetInfo: The typed dataset information object.
     """
-    info = load_json(local_dir / INFO_PATH)
-    for ft in info["features"].values():
-        ft["shape"] = tuple(ft["shape"])
-    return info
+    raw = load_json(local_dir / INFO_PATH)
+    return DatasetInfo.from_dict(raw)
 
 
 def write_stats(stats: dict, local_dir: Path) -> None:

src/lerobot/datasets/lerobot_dataset.py

@@ -630,6 +630,8 @@ class LeRobotDataset(torch.utils.data.Dataset):
         streaming_encoding: bool = False,
         encoder_queue_maxsize: int = 30,
         encoder_threads: int | None = None,
+        video_files_size_in_mb: int | None = None,
+        data_files_size_in_mb: int | None = None,
     ) -> "LeRobotDataset":
         """Create a new LeRobotDataset from scratch for recording data.
 
@@ -677,6 +679,8 @@ class LeRobotDataset(torch.utils.data.Dataset):
             root=root,
             use_videos=use_videos,
             metadata_buffer_size=metadata_buffer_size,
+            video_files_size_in_mb=video_files_size_in_mb,
+            data_files_size_in_mb=data_files_size_in_mb,
         )
         obj.repo_id = obj.meta.repo_id
         obj._requested_root = obj.meta.root

src/lerobot/datasets/multi_dataset.py

@@ -123,7 +123,7 @@ class MultiLeRobotDataset(torch.utils.data.Dataset):
 
         NOTE: Fow now, this relies on a check in __init__ to make sure all sub-datasets have the same info.
         """
-        return self._datasets[0].meta.info["fps"]
+        return self._datasets[0].meta.info.fps
 
     @property
     def video(self) -> bool:
@@ -133,7 +133,7 @@ class MultiLeRobotDataset(torch.utils.data.Dataset):
 
         NOTE: Fow now, this relies on a check in __init__ to make sure all sub-datasets have the same info.
         """
-        return self._datasets[0].meta.info.get("video", False)
+        return len(self._datasets[0].meta.video_keys) > 0
 
     @property
     def features(self) -> datasets.Features:

src/lerobot/datasets/streaming_dataset.py

@@ -434,7 +434,7 @@ class StreamingLeRobotDataset(torch.utils.data.IterableDataset):
 
     def _make_padding_camera_frame(self, camera_key: str):
         """Variable-shape padding frame for given camera keys, given in (H, W, C)"""
-        return torch.zeros(self.meta.info["features"][camera_key]["shape"]).permute(-1, 0, 1)
+        return torch.zeros(self.meta.info.features[camera_key]["shape"]).permute(-1, 0, 1)
 
     def _get_video_frame_padding_mask(
         self,

src/lerobot/datasets/utils.py

@@ -14,9 +14,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import contextlib
+import dataclasses
 import importlib.resources
 import json
 import logging
+from dataclasses import dataclass, field
 from pathlib import Path
 
 import datasets
@@ -70,9 +72,12 @@ class ForwardCompatibilityError(CompatibilityError):
         super().__init__(message)
 
 
+logger = logging.getLogger(__name__)
+
+
 DEFAULT_CHUNK_SIZE = 1000  # Max number of files per chunk
-DEFAULT_DATA_FILE_SIZE_IN_MB = 50  # Max size per file
-DEFAULT_VIDEO_FILE_SIZE_IN_MB = 100  # Max size per file
+DEFAULT_DATA_FILE_SIZE_IN_MB = 100  # Max size per file
+DEFAULT_VIDEO_FILE_SIZE_IN_MB = 200  # Max size per file
 
 INFO_PATH = "meta/info.json"
 STATS_PATH = "meta/stats.json"
@@ -94,6 +99,123 @@ LEGACY_EPISODES_STATS_PATH = "meta/episodes_stats.jsonl"
 LEGACY_TASKS_PATH = "meta/tasks.jsonl"
 
 
+@dataclass
+class DatasetInfo:
+    """Typed representation of the ``meta/info.json`` file for a LeRobot dataset.
+
+    Replaces the previously untyped ``dict`` returned by ``load_info()`` and
+    created by ``create_empty_dataset_info()``.  Using a dataclass provides
+    explicit field definitions, IDE auto-completion, and validation at
+    construction time.
+    """
+
+    codebase_version: str
+    fps: int
+    features: dict[str, dict]
+
+    # Episode / frame counters — start at zero for new datasets
+    total_episodes: int = 0
+    total_frames: int = 0
+    total_tasks: int = 0
+
+    # Storage settings
+    chunks_size: int = field(default=DEFAULT_CHUNK_SIZE)
+    data_files_size_in_mb: int = field(default=DEFAULT_DATA_FILE_SIZE_IN_MB)
+    video_files_size_in_mb: int = field(default=DEFAULT_VIDEO_FILE_SIZE_IN_MB)
+
+    # File path templates
+    data_path: str = field(default=DEFAULT_DATA_PATH)
+    video_path: str | None = field(default=DEFAULT_VIDEO_PATH)
+
+    # Optional metadata
+    robot_type: str | None = None
+    splits: dict[str, str] = field(default_factory=dict)
+
+    def __post_init__(self) -> None:
+        # Coerce feature shapes from list to tuple — JSON deserialisation
+        # returns lists, but the rest of the codebase expects tuples.
+        for ft in self.features.values():
+            if isinstance(ft.get("shape"), list):
+                ft["shape"] = tuple(ft["shape"])
+
+        if self.fps <= 0:
+            raise ValueError(f"fps must be positive, got {self.fps}")
+        if self.chunks_size <= 0:
+            raise ValueError(f"chunks_size must be positive, got {self.chunks_size}")
+        if self.data_files_size_in_mb <= 0:
+            raise ValueError(f"data_files_size_in_mb must be positive, got {self.data_files_size_in_mb}")
+        if self.video_files_size_in_mb <= 0:
+            raise ValueError(f"video_files_size_in_mb must be positive, got {self.video_files_size_in_mb}")
+
+    def to_dict(self) -> dict:
+        """Return a JSON-serialisable dict.
+
+        Converts tuple shapes back to lists so ``json.dump`` can handle them.
+        """
+        d = dataclasses.asdict(self)
+        for ft in d["features"].values():
+            if isinstance(ft.get("shape"), tuple):
+                ft["shape"] = list(ft["shape"])
+        return d
+
+    @classmethod
+    def from_dict(cls, data: dict) -> "DatasetInfo":
+        """Construct from a raw dict (e.g. loaded directly from JSON).
+
+        Unknown keys are ignored for forward compatibility with datasets that
+        carry additional fields (e.g. ``total_videos`` from v2.x). A warning is
+        logged when such fields are present.
+        """
+        known = {f.name for f in dataclasses.fields(cls)}
+        unknown = sorted(k for k in data if k not in known)
+        if unknown:
+            logger.warning(f"Unknown fields in DatasetInfo: {unknown}. These will be ignored.")
+        return cls(**{k: v for k, v in data.items() if k in known})
+
+    # ---------------------------------------------------------------------------
+    # Temporary dict-style compatibility layer
+    # Allows existing ``info["key"]`` call-sites to keep working without changes.
+    # Once all callers have been migrated to attribute access, remove these.
+    # ---------------------------------------------------------------------------
+    def __getitem__(self, key: str):
+        import warnings
+
+        warnings.warn(
+            f"Accessing DatasetInfo with dict-style syntax info['{key}'] is deprecated. "
+            f"Use attribute access info.{key} instead.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        try:
+            return getattr(self, key)
+        except AttributeError as err:
+            raise KeyError(key) from err
+
+    def __setitem__(self, key: str, value) -> None:
+        import warnings
+
+        warnings.warn(
+            f"Setting DatasetInfo with dict-style syntax info['{key}'] = ... is deprecated. "
+            f"Use attribute assignment info.{key} = ... instead.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        if not hasattr(self, key):
+            raise KeyError(f"DatasetInfo has no field '{key}'")
+        setattr(self, key, value)
+
+    def __contains__(self, key: str) -> bool:
+        """Check if a field exists (dict-like interface)."""
+        return hasattr(self, key)
+
+    def get(self, key: str, default=None):
+        """Get attribute value with default fallback (dict-like interface)."""
+        try:
+            return getattr(self, key)
+        except AttributeError:
+            return default
+
+
 def has_legacy_hub_download_metadata(root: Path) -> bool:
     """Return ``True`` when *root* looks like a legacy Hub ``local_dir`` mirror.
 
@@ -294,7 +416,7 @@ def create_branch(repo_id: str, *, branch: str, repo_type: str | None = None) ->
 
 def create_lerobot_dataset_card(
     tags: list | None = None,
-    dataset_info: dict | None = None,
+    dataset_info: DatasetInfo | None = None,
     **kwargs,
 ) -> DatasetCard:
     """Create a `DatasetCard` for a LeRobot dataset.
@@ -305,7 +427,7 @@ def create_lerobot_dataset_card(
 
     Args:
         tags (list | None): A list of tags to add to the dataset card.
-        dataset_info (dict | None): The dataset's info dictionary, which will
+        dataset_info (DatasetInfo | None): The dataset's info object, which will
             be displayed on the card.
         **kwargs: Additional keyword arguments to populate the card template.
 
@@ -318,7 +440,7 @@ def create_lerobot_dataset_card(
         card_tags += tags
     if dataset_info:
         dataset_structure = "[meta/info.json](meta/info.json):\n"
-        dataset_structure += f"```json\n{json.dumps(dataset_info, indent=4)}\n```\n"
+        dataset_structure += f"```json\n{json.dumps(dataset_info.to_dict(), indent=4)}\n```\n"
         kwargs = {**kwargs, "dataset_structure": dataset_structure}
     card_data = DatasetCardData(
         license=kwargs.get("license"),

src/lerobot/policies/__init__.py

@@ -16,6 +16,7 @@ from lerobot.utils.action_interpolator import ActionInterpolator as ActionInterp
 
 from .act.configuration_act import ACTConfig as ACTConfig
 from .diffusion.configuration_diffusion import DiffusionConfig as DiffusionConfig
+from .eo1.configuration_eo1 import EO1Config as EO1Config
 from .factory import get_policy_class, make_policy, make_policy_config, make_pre_post_processors
 from .groot.configuration_groot import GrootConfig as GrootConfig
 from .multi_task_dit.configuration_multi_task_dit import MultiTaskDiTConfig as MultiTaskDiTConfig
@@ -24,8 +25,6 @@ from .pi0_fast.configuration_pi0_fast import PI0FastConfig as PI0FastConfig
 from .pi05.configuration_pi05 import PI05Config as PI05Config
 from .pretrained import PreTrainedPolicy as PreTrainedPolicy
 from .sac.configuration_sac import SACConfig as SACConfig
-from .sac.reward_model.configuration_classifier import RewardClassifierConfig as RewardClassifierConfig
-from .sarm.configuration_sarm import SARMConfig as SARMConfig
 from .smolvla.configuration_smolvla import SmolVLAConfig as SmolVLAConfig
 from .tdmpc.configuration_tdmpc import TDMPCConfig as TDMPCConfig
 from .utils import make_robot_action, prepare_observation_for_inference
@@ -43,12 +42,11 @@ __all__ = [
     "DiffusionConfig",
     "GrootConfig",
     "MultiTaskDiTConfig",
+    "EO1Config",
     "PI0Config",
     "PI0FastConfig",
     "PI05Config",
-    "RewardClassifierConfig",
     "SACConfig",
-    "SARMConfig",
     "SmolVLAConfig",
     "TDMPCConfig",
     "VQBeTConfig",

src/lerobot/policies/act/modeling_act.py

@@ -142,9 +142,10 @@ class ACTPolicy(PreTrainedPolicy):
 
         actions_hat, (mu_hat, log_sigma_x2_hat) = self.model(batch)
 
-        l1_loss = (
-            F.l1_loss(batch[ACTION], actions_hat, reduction="none") * ~batch["action_is_pad"].unsqueeze(-1)
-        ).mean()
+        abs_err = F.l1_loss(batch[ACTION], actions_hat, reduction="none")
+        valid_mask = ~batch["action_is_pad"].unsqueeze(-1)
+        num_valid = valid_mask.sum() * abs_err.shape[-1]
+        l1_loss = (abs_err * valid_mask).sum() / num_valid.clamp_min(1)
 
         loss_dict = {"l1_loss": l1_loss.item()}
         if self.config.use_vae:

src/lerobot/policies/diffusion/modeling_diffusion.py

@@ -380,7 +380,9 @@ class DiffusionModel(nn.Module):
                     f"{self.config.do_mask_loss_for_padding=}."
                 )
             in_episode_bound = ~batch["action_is_pad"]
-            loss = loss * in_episode_bound.unsqueeze(-1)
+            mask = in_episode_bound.unsqueeze(-1)
+            num_valid = mask.sum() * loss.shape[-1]
+            return (loss * mask).sum() / num_valid.clamp_min(1)
 
         return loss.mean()
 

src/lerobot/policies/eo1/README.md

@@ -0,0 +1 @@
+../../../../docs/source/eo1.mdx

src/lerobot/policies/eo1/__init__.py

@@ -0,0 +1,7 @@
+#!/usr/bin/env python
+
+from .configuration_eo1 import EO1Config
+from .modeling_eo1 import EO1Policy
+from .processor_eo1 import make_eo1_pre_post_processors
+
+__all__ = ["EO1Config", "EO1Policy", "make_eo1_pre_post_processors"]

src/lerobot/policies/eo1/configuration_eo1.py

@@ -0,0 +1,193 @@
+#!/usr/bin/env python
+
+# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import annotations
+
+from copy import deepcopy
+from dataclasses import dataclass, field
+from typing import TYPE_CHECKING
+
+from lerobot.configs.policies import PreTrainedConfig
+from lerobot.configs.types import FeatureType, NormalizationMode, PolicyFeature
+from lerobot.optim.optimizers import AdamWConfig
+from lerobot.optim.schedulers import CosineDecayWithWarmupSchedulerConfig
+from lerobot.utils.constants import ACTION, OBS_STATE
+from lerobot.utils.import_utils import _transformers_available, require_package
+
+if TYPE_CHECKING or _transformers_available:
+    from transformers.models.qwen2_5_vl.configuration_qwen2_5_vl import (
+        Qwen2_5_VLConfig,
+        Qwen2_5_VLTextConfig,
+        Qwen2_5_VLVisionConfig,
+    )
+else:
+    Qwen2_5_VLConfig = None
+    Qwen2_5_VLTextConfig = None
+    Qwen2_5_VLVisionConfig = None
+
+
+@PreTrainedConfig.register_subclass("eo1")
+@dataclass
+class EO1Config(PreTrainedConfig):
+    """Configuration for native EO1 policy integration in LeRobot."""
+
+    vlm_base: str = "Qwen/Qwen2.5-VL-3B-Instruct"
+    vlm_config: dict | None = None
+
+    # Vision processor settings.
+    image_min_pixels: int | None = 64 * 28 * 28
+    image_max_pixels: int | None = 128 * 28 * 28
+    use_fast_processor: bool = False
+
+    # Execution and action horizon.
+    n_obs_steps: int = 1
+    chunk_size: int = 8
+    n_action_steps: int = 8
+
+    # State/action padding to match EO1 flow head dimensionality.
+    max_state_dim: int = 32
+    max_action_dim: int = 32
+
+    # Flow matching sampling.
+    num_denoise_steps: int = 10
+    num_action_layers: int = 2
+    action_act: str = "linear"
+    time_sampling_beta_alpha: float = 1.5
+    time_sampling_beta_beta: float = 1.0
+    time_sampling_scale: float = 0.999
+    time_sampling_offset: float = 0.001
+    min_period: float = 4e-3
+    max_period: float = 4.0
+    supervise_padding_action_dims: bool = True
+    supervise_padding_actions: bool = True
+
+    # Policy-level dtype request for the Qwen backbone.
+    # - "auto": follow the backbone config/checkpoint default dtype. For Qwen2.5-VL this resolves to bf16.
+    #           The EO1 flow-matching head still keeps its own parameters in fp32.
+    # - "bfloat16": force the backbone to initialize/load in bf16 regardless of the saved config default.
+    # - "float32": force the backbone to initialize/load in fp32 for maximum numerical conservatism.
+    dtype: str = "auto"  # Options: "auto", "bfloat16", "float32"
+    force_fp32_autocast: bool = True
+
+    # Optional attention backend request passed through to the Qwen backbone.
+    # Common values: None, "eager", "sdpa", "flash_attention_2".
+    attn_implementation: str | None = None
+
+    # Training settings.
+    gradient_checkpointing: bool = False  # Enable gradient checkpointing for memory optimization
+
+    normalization_mapping: dict[str, NormalizationMode] = field(
+        default_factory=lambda: {
+            "VISUAL": NormalizationMode.IDENTITY,
+            "STATE": NormalizationMode.MEAN_STD,
+            "ACTION": NormalizationMode.MEAN_STD,
+        }
+    )
+
+    # Optimizer settings aligned with EO1/experiments/2_libero/train.sh and EO1 TrainPipelineConfig defaults.
+    optimizer_lr: float = 1e-4
+    optimizer_betas: tuple[float, float] = (0.9, 0.999)
+    optimizer_eps: float = 1e-8
+    optimizer_weight_decay: float = 0.1
+    optimizer_grad_clip_norm: float = 1.0
+
+    # Scheduler settings aligned with EO1 train.sh: cosine schedule with warmup_ratio=0.03.
+    # Note: These will auto-scale if --steps < scheduler_decay_steps
+    # For example, --steps=3000 will scale warmup to 100 and decay to 3000
+    scheduler_warmup_steps: int = 900  # 0.03 * 30_000 long-run steps
+    scheduler_decay_steps: int = 30_000
+    scheduler_decay_lr: float = 0.0
+
+    def __post_init__(self):
+        super().__post_init__()
+
+        if self.n_action_steps > self.chunk_size:
+            raise ValueError(
+                f"n_action_steps ({self.n_action_steps}) cannot be greater than chunk_size ({self.chunk_size})"
+            )
+
+        # Populate the serialized backbone config only when the caller did not provide one.
+        if self.vlm_config is None:
+            require_package("transformers", extra="eo1")
+            self.vlm_config = Qwen2_5_VLConfig.from_pretrained(self.vlm_base).to_dict()
+
+    @property
+    def vlm_backbone_config(self) -> Qwen2_5_VLConfig:
+        require_package("transformers", extra="eo1")
+        config_dict = deepcopy(self.vlm_config)
+        if self.attn_implementation is not None:
+            config_dict["attn_implementation"] = self.attn_implementation
+        return Qwen2_5_VLConfig(**config_dict)
+
+    @property
+    def text_config(self) -> Qwen2_5_VLTextConfig:
+        return self.vlm_backbone_config.text_config
+
+    @property
+    def vision_config(self) -> Qwen2_5_VLVisionConfig:
+        return self.vlm_backbone_config.vision_config
+
+    def validate_features(self) -> None:
+        """Validate and set up EO1 input and output features."""
+        image_features = [key for key, feat in self.input_features.items() if feat.type == FeatureType.VISUAL]
+        if not image_features:
+            raise ValueError(
+                "EO1 policy requires at least one visual input feature. "
+                "No features of type FeatureType.VISUAL found in input_features."
+            )
+
+        if OBS_STATE not in self.input_features:
+            state_feature = PolicyFeature(
+                type=FeatureType.STATE,
+                shape=(self.max_state_dim,),
+            )
+            self.input_features[OBS_STATE] = state_feature
+
+        if ACTION not in self.output_features:
+            action_feature = PolicyFeature(
+                type=FeatureType.ACTION,
+                shape=(self.max_action_dim,),
+            )
+            self.output_features[ACTION] = action_feature
+
+    def get_optimizer_preset(self) -> AdamWConfig:
+        return AdamWConfig(
+            lr=self.optimizer_lr,
+            betas=self.optimizer_betas,
+            eps=self.optimizer_eps,
+            weight_decay=self.optimizer_weight_decay,
+            grad_clip_norm=self.optimizer_grad_clip_norm,
+        )
+
+    def get_scheduler_preset(self):
+        return CosineDecayWithWarmupSchedulerConfig(
+            peak_lr=self.optimizer_lr,
+            decay_lr=self.scheduler_decay_lr,
+            num_warmup_steps=self.scheduler_warmup_steps,
+            num_decay_steps=self.scheduler_decay_steps,
+        )
+
+    @property
+    def observation_delta_indices(self) -> None:
+        return None
+
+    @property
+    def action_delta_indices(self) -> list[int]:
+        return list(range(self.chunk_size))
+
+    @property
+    def reward_delta_indices(self) -> None:
+        return None

src/lerobot/policies/eo1/modeling_eo1.py

@@ -0,0 +1,620 @@
+#!/usr/bin/env python
+
+# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import annotations
+
+import contextlib
+import logging
+import math
+from collections import deque
+from typing import TYPE_CHECKING, Any
+
+import torch
+import torch.nn as nn
+import torch.nn.functional as F  # noqa: N812
+import torch.utils.checkpoint
+from torch import Tensor
+
+from lerobot.policies.eo1.configuration_eo1 import EO1Config
+from lerobot.policies.pretrained import PreTrainedPolicy
+from lerobot.utils.constants import ACTION, OBS_STATE
+from lerobot.utils.import_utils import _transformers_available, require_package
+
+if TYPE_CHECKING or _transformers_available:
+    from transformers.activations import ACT2FN
+    from transformers.models.qwen2_5_vl import Qwen2_5_VLForConditionalGeneration
+    from transformers.utils import torch_compilable_check
+else:
+    ACT2FN = None
+    Qwen2_5_VLForConditionalGeneration = None
+    torch_compilable_check = None
+
+logger = logging.getLogger(__name__)
+
+
+def pad_vector(vector, new_dim):
+    """Pad the last dimension of a vector to new_dim with zeros.
+
+    Can be (batch_size x sequence_length x features_dimension)
+    or (batch_size x features_dimension)
+    """
+    if vector.shape[-1] >= new_dim:
+        return vector
+    return F.pad(vector, (0, new_dim - vector.shape[-1]))
+
+
+class EO1Policy(PreTrainedPolicy):
+    """EO1 policy wrapper for LeRobot robot-only training/evaluation."""
+
+    config_class = EO1Config
+    name = "eo1"
+
+    def __init__(self, config: EO1Config, **kwargs):
+        require_package("transformers", extra="eo1")
+        super().__init__(config)
+        config.validate_features()
+        self.config = config
+
+        if config.pretrained_path is None:
+            # Initialize from pretrained VLM
+            vlm_backbone = Qwen2_5_VLForConditionalGeneration.from_pretrained(
+                config.vlm_base,
+                dtype=config.dtype,
+                attn_implementation=config.attn_implementation,
+            )
+        else:
+            vlm_backbone = Qwen2_5_VLForConditionalGeneration._from_config(
+                config.vlm_backbone_config,
+                dtype=config.vlm_backbone_config.dtype if config.dtype == "auto" else config.dtype,
+            )
+
+        self.model = EO1VisionFlowMatchingModel(config, vlm_backbone)
+        if config.gradient_checkpointing:
+            self.model.gradient_checkpointing_enable()
+
+        self.model.to(config.device)
+        self.reset()
+
+    def reset(self):
+        self._action_queue = deque(maxlen=self.config.n_action_steps)
+
+    @staticmethod
+    def _get_model_inputs(batch: dict[str, Tensor], excluded_keys: set[str]) -> dict[str, Tensor]:
+        return {key: value for key, value in batch.items() if key not in excluded_keys}
+
+    def forward(self, batch: dict[str, Tensor]) -> tuple[Tensor, dict]:
+        state = self.prepare_state(batch[OBS_STATE])
+        actions = self.prepare_action(batch[ACTION])
+        model_inputs = self._get_model_inputs(batch, {OBS_STATE, ACTION})
+        loss = self.model(states=state, action=actions, **model_inputs)
+
+        loss_dict = {"loss": loss.item()}
+        return loss, loss_dict
+
+    @torch.no_grad()
+    def predict_action_chunk(self, batch: dict[str, Tensor], **kwargs) -> Tensor:
+        self.eval()
+
+        states = self.prepare_state(batch[OBS_STATE])
+        model_inputs = self._get_model_inputs(batch, {OBS_STATE})
+        actions = self.model.sample_actions(states=states, **model_inputs).to(torch.float32)
+
+        original_action_dim = self.config.output_features[ACTION].shape[0]
+        return actions[:, :, :original_action_dim]
+
+    def prepare_state(self, state: Tensor) -> Tensor:
+        return pad_vector(state, self.config.max_state_dim)
+
+    def prepare_action(self, action: Tensor) -> Tensor:
+        return pad_vector(action, self.config.max_action_dim)
+
+    @torch.no_grad()
+    def select_action(self, batch: dict[str, Tensor]) -> Tensor:
+        self.eval()
+
+        if len(self._action_queue) == 0:
+            actions = self.predict_action_chunk(batch)[:, : self.config.n_action_steps]
+            self._action_queue.extend(actions.transpose(0, 1))
+
+        return self._action_queue.popleft()
+
+    def get_optim_params(self) -> dict:
+        return self.parameters()
+
+
+def get_safe_dtype(target_dtype, device_type):
+    """Get a safe dtype for the given device type."""
+    if device_type == "mps" and target_dtype == torch.float64:
+        return torch.float32
+    if device_type == "cpu":
+        # CPU doesn't support bfloat16, use float32 instead
+        if target_dtype == torch.bfloat16:
+            return torch.float32
+        if target_dtype == torch.float64:
+            return torch.float64
+    return target_dtype
+
+
+def create_sinusoidal_pos_embedding(  # see openpi `create_sinusoidal_pos_embedding` (exact copy)
+    time: torch.Tensor, dimension: int, min_period: float, max_period: float, device="cpu"
+) -> Tensor:
+    """Computes sine-cosine positional embedding vectors for scalar positions."""
+    if dimension % 2 != 0:
+        raise ValueError(f"dimension ({dimension}) must be divisible by 2")
+
+    if time.ndim != 1:
+        raise ValueError("The time tensor is expected to be of shape `(batch_size, )`.")
+
+    dtype = get_safe_dtype(torch.float64, device.type)
+    fraction = torch.linspace(0.0, 1.0, dimension // 2, dtype=dtype, device=device)
+    period = min_period * (max_period / min_period) ** fraction
+
+    # Compute the outer product
+    scaling_factor = 1.0 / period * 2 * math.pi
+    sin_input = scaling_factor[None, :] * time[:, None]
+    return torch.cat([torch.sin(sin_input), torch.cos(sin_input)], dim=1)
+
+
+def sample_beta(alpha, beta, bsize, device):  # see openpi `sample_beta` (exact copy)
+    # Beta sampling uses _sample_dirichlet which isn't implemented for MPS, so sample on CPU
+    alpha_t = torch.tensor(alpha, dtype=torch.float32)
+    beta_t = torch.tensor(beta, dtype=torch.float32)
+    dist = torch.distributions.Beta(alpha_t, beta_t)
+    return dist.sample((bsize,)).to(device)
+
+
+class EO1VisionActionProjector(torch.nn.Sequential):
+    """This block implements the multi-layer perceptron (MLP) module."""
+
+    def __init__(
+        self,
+        in_channels: int,
+        out_channels: int,
+        num_layers: int = 2,
+        activation_layer: str = "linear",
+        bias: bool = True,
+        device: Any = None,
+        dtype: torch.dtype = torch.float32,
+    ):
+        layers = []
+        in_dim = in_channels
+        hidden_channels = [in_dim] * (num_layers - 1) + [out_channels]
+        for hidden_dim in hidden_channels[:-1]:
+            layers.append(torch.nn.Linear(in_dim, hidden_dim, bias=bias, dtype=dtype, device=device))
+            layers.append(ACT2FN[activation_layer])
+            in_dim = hidden_dim
+        layers.append(torch.nn.Linear(in_dim, hidden_channels[-1], bias=bias, dtype=dtype, device=device))
+        super().__init__(*layers)
+
+    @property
+    def dtype(self):
+        return self[0].weight.dtype
+
+
+class EO1VisionFlowMatchingModel(nn.Module):
+    def __init__(
+        self,
+        config: EO1Config,
+        vlm_backbone: Qwen2_5_VLForConditionalGeneration | None = None,
+    ):
+        require_package("transformers", extra="eo1")
+        super().__init__()
+
+        self.config = config
+        # Preserve the backbone dtype selected at construction time so Qwen's fp32 rotary buffers stay intact.
+        self.vlm_backbone = vlm_backbone
+        self.hidden_size = self.vlm_backbone.config.text_config.hidden_size
+        max_state_dim = config.max_state_dim
+        max_action_dim = config.max_action_dim
+        self.state_proj = nn.Linear(max_state_dim, self.hidden_size, dtype=torch.float32)
+        self.action_in_proj = nn.Linear(max_action_dim, self.hidden_size, dtype=torch.float32)
+        self.action_out_proj = EO1VisionActionProjector(
+            self.hidden_size,
+            max_action_dim,
+            config.num_action_layers,
+            config.action_act,
+            dtype=torch.float32,
+        )
+        self.action_time_mlp_in = nn.Linear(self.hidden_size * 2, self.hidden_size, dtype=torch.float32)
+        self.action_time_mlp_out = nn.Linear(self.hidden_size, self.hidden_size, dtype=torch.float32)
+        self.gradient_checkpointing_enabled = False
+
+    def get_input_embeddings(self):
+        return self.vlm_backbone.get_input_embeddings()
+
+    def flow_head_autocast_context(self):
+        if self.config.force_fp32_autocast:
+            return torch.autocast(
+                device_type=self.state_proj.weight.device.type,
+                enabled=False,
+            )
+        return contextlib.nullcontext()
+
+    def gradient_checkpointing_enable(self):
+        """Enable gradient checkpointing for the Qwen2.5-VL backbone."""
+        self.gradient_checkpointing_enabled = True
+        self.vlm_backbone.gradient_checkpointing_enable(
+            gradient_checkpointing_kwargs={"use_reentrant": False}
+        )
+        logger.info("Enabled gradient checkpointing for EO1VisionFlowMatchingModel")
+
+    def gradient_checkpointing_disable(self):
+        """Disable gradient checkpointing for the Qwen2.5-VL backbone."""
+        self.gradient_checkpointing_enabled = False
+        self.vlm_backbone.gradient_checkpointing_disable()
+        logger.info("Disabled gradient checkpointing for EO1VisionFlowMatchingModel")
+
+    def _apply_checkpoint(self, func, *args, **kwargs):
+        """Apply manual gradient checkpointing to EO1 flow-head computations when training."""
+        if self.gradient_checkpointing_enabled and self.training and torch.is_grad_enabled():
+            return torch.utils.checkpoint.checkpoint(
+                func, *args, use_reentrant=False, preserve_rng_state=False, **kwargs
+            )
+        return func(*args, **kwargs)
+
+    def sample_noise(self, shape, device):
+        noise = torch.normal(
+            mean=0.0,
+            std=1.0,
+            size=shape,
+            dtype=torch.float32,
+            device=device,
+        )
+        return noise
+
+    def sample_time(self, bsize, device):
+        time_beta = sample_beta(
+            self.config.time_sampling_beta_alpha, self.config.time_sampling_beta_beta, bsize, device
+        )
+        time = time_beta * self.config.time_sampling_scale + self.config.time_sampling_offset
+        return time.to(dtype=torch.float32, device=device)
+
+    def get_placeholder_mask(
+        self,
+        input_ids: torch.LongTensor | None,
+        inputs_embeds: torch.FloatTensor | None,
+        state_features: torch.FloatTensor | None = None,
+        action_features: torch.FloatTensor | None = None,
+        *,
+        state_token_id: int,
+        action_token_id: int,
+    ) -> tuple[torch.BoolTensor, torch.BoolTensor]:
+        """Return EO1 state/action placeholder masks, following Qwen's multimodal mask style."""
+        if input_ids is None:
+            special_state_mask = inputs_embeds == self.get_input_embeddings()(
+                torch.tensor(state_token_id, dtype=torch.long, device=inputs_embeds.device)
+            )
+            special_state_mask = special_state_mask.all(-1)
+            special_action_mask = inputs_embeds == self.get_input_embeddings()(
+                torch.tensor(action_token_id, dtype=torch.long, device=inputs_embeds.device)
+            )
+            special_action_mask = special_action_mask.all(-1)
+        else:
+            special_state_mask = input_ids == state_token_id
+            special_action_mask = input_ids == action_token_id
+
+        n_state_tokens = special_state_mask.sum()
+        special_state_mask = (
+            special_state_mask.unsqueeze(-1).expand_as(inputs_embeds).to(inputs_embeds.device)
+        )
+        if state_features is not None:
+            torch_compilable_check(
+                inputs_embeds[special_state_mask].numel() == state_features.numel(),
+                f"State features and state tokens do not match, tokens: {n_state_tokens}, features: {state_features.shape[0]}",
+            )
+
+        n_action_tokens = special_action_mask.sum()
+        special_action_mask = (
+            special_action_mask.unsqueeze(-1).expand_as(inputs_embeds).to(inputs_embeds.device)
+        )
+        if action_features is not None:
+            torch_compilable_check(
+                inputs_embeds[special_action_mask].numel() == action_features.numel(),
+                f"Action features and action tokens do not match, tokens: {n_action_tokens}, features: {action_features.shape[0]}",
+            )
+
+        return special_state_mask, special_action_mask
+
+    def embed_prefix(
+        self,
+        input_ids: torch.LongTensor,
+        states: torch.Tensor,
+        *,
+        state_token_id: int,
+        action_token_id: int,
+    ) -> torch.FloatTensor:
+        """Embed the EO1 prefix tokens before native Qwen injects multimodal features."""
+
+        # Get the input embeddings for the input IDs
+        def input_embed_func(input_ids: torch.LongTensor) -> torch.FloatTensor:
+            return self.get_input_embeddings()(input_ids)
+
+        inputs_embeds = self._apply_checkpoint(input_embed_func, input_ids)
+
+        # Project the states to the hidden size
+        def state_proj_func(states: torch.Tensor) -> torch.FloatTensor:
+            with self.flow_head_autocast_context():
+                states = states.to(dtype=self.state_proj.weight.dtype)
+                return self.state_proj(states)
+
+        state_embs = self._apply_checkpoint(state_proj_func, states)
+        state_mask, _ = self.get_placeholder_mask(
+            input_ids,
+            inputs_embeds,
+            state_features=state_embs,
+            state_token_id=state_token_id,
+            action_token_id=action_token_id,
+        )
+        state_embs = state_embs.to(inputs_embeds.device, inputs_embeds.dtype)
+        inputs_embeds = inputs_embeds.masked_scatter(state_mask, state_embs)
+        return inputs_embeds
+
+    def embed_suffix(
+        self,
+        timestep: torch.Tensor,
+        noisy_actions: torch.Tensor,
+    ) -> torch.FloatTensor:
+        """Embed the suffix"""
+
+        def action_proj_func(noisy_actions: torch.Tensor) -> torch.FloatTensor:
+            with self.flow_head_autocast_context():
+                noisy_actions = noisy_actions.to(dtype=self.action_in_proj.weight.dtype)
+                return self.action_in_proj(noisy_actions)
+
+        action_embs = self._apply_checkpoint(action_proj_func, noisy_actions)
+        time_embs = create_sinusoidal_pos_embedding(
+            timestep,
+            self.hidden_size,
+            min_period=self.config.min_period,
+            max_period=self.config.max_period,
+            device=action_embs.device,
+        )
+        time_embs = time_embs.to(dtype=action_embs.dtype)
+        time_embs = time_embs[:, None, :].expand_as(action_embs)
+        action_time_embs = torch.cat([action_embs, time_embs], dim=2)
+
+        def mlp_func(action_time_embs: torch.Tensor) -> torch.FloatTensor:
+            with self.flow_head_autocast_context():
+                action_time_embs = action_time_embs.to(dtype=self.action_time_mlp_in.weight.dtype)
+                action_time_embs = self.action_time_mlp_in(action_time_embs)
+                action_time_embs = F.silu(action_time_embs)
+                return self.action_time_mlp_out(action_time_embs)
+
+        action_time_embs = self._apply_checkpoint(mlp_func, action_time_embs)
+        return action_time_embs
+
+    def forward(
+        self,
+        input_ids: torch.LongTensor | None = None,
+        attention_mask: torch.LongTensor | None = None,
+        pixel_values: torch.FloatTensor | None = None,
+        image_grid_thw: torch.LongTensor | None = None,
+        mm_token_type_ids: torch.IntTensor | None = None,
+        states: torch.FloatTensor | None = None,
+        action: torch.FloatTensor | None = None,
+        action_is_pad: torch.BoolTensor | None = None,
+        *,
+        state_token_id: int,
+        action_token_id: int,
+        **kwargs,
+    ) -> Tensor:
+        """Run the EO1 training forward pass and compute the flow-matching loss."""
+
+        # 1. Build the EO1 prefix with state placeholders resolved.
+        inputs_embeds = self.embed_prefix(
+            input_ids,
+            states=states,
+            state_token_id=state_token_id,
+            action_token_id=action_token_id,
+        )
+
+        # 2. Sample the diffusion target and replace the action placeholders.
+        time = self.sample_time(action.shape[0], inputs_embeds.device)
+        noise = self.sample_noise(action.shape, inputs_embeds.device)
+
+        time_expanded = time[:, None, None]
+        x_t = time_expanded * noise + (1 - time_expanded) * action
+        u_t = noise - action
+        action_time_embs = self.embed_suffix(time, x_t)
+        _, action_mask = self.get_placeholder_mask(
+            input_ids,
+            inputs_embeds,
+            action_features=action_time_embs,
+            state_token_id=state_token_id,
+            action_token_id=action_token_id,
+        )
+        action_time_embs = action_time_embs.to(inputs_embeds.device, inputs_embeds.dtype)
+        inputs_embeds = inputs_embeds.masked_scatter(action_mask, action_time_embs)
+
+        # 3. Optionally drop padded action tokens from backbone attention.
+        if attention_mask is not None:
+            attention_mask = attention_mask.to(inputs_embeds.device)
+
+        if not self.config.supervise_padding_actions:
+            action_is_pad = action_is_pad.to(device=inputs_embeds.device, dtype=torch.bool)
+            action_token_mask = action_mask[..., 0]
+            action_padding_mask = torch.zeros_like(action_token_mask)
+            action_padding_mask = action_padding_mask.masked_scatter(
+                action_token_mask,
+                action_is_pad.reshape(-1),
+            )
+            attention_mask = attention_mask.masked_fill(action_padding_mask, 0)
+
+        # 4. Run the Qwen backbone on the fused EO1 sequence.
+        def vlm_forward_func(
+            input_ids: torch.LongTensor,
+            attention_mask: torch.Tensor | None,
+            inputs_embeds: torch.FloatTensor,
+            pixel_values: torch.Tensor | None,
+            image_grid_thw: torch.LongTensor | None,
+            mm_token_type_ids: torch.IntTensor | None,
+        ) -> torch.FloatTensor:
+            outputs = self.vlm_backbone.model(
+                input_ids=input_ids,
+                attention_mask=attention_mask,
+                inputs_embeds=inputs_embeds,
+                pixel_values=pixel_values,
+                image_grid_thw=image_grid_thw,
+                mm_token_type_ids=mm_token_type_ids,
+                use_cache=False,
+                output_hidden_states=False,
+                return_dict=True,
+            )
+            return outputs.last_hidden_state
+
+        hidden_states = self._apply_checkpoint(
+            vlm_forward_func,
+            input_ids,
+            attention_mask,
+            inputs_embeds,
+            pixel_values,
+            image_grid_thw,
+            mm_token_type_ids,
+        )
+        action_hidden_states = hidden_states[action_mask[..., 0]]
+
+        # 5. Project the action-token hidden states back to the flow target space.
+        def action_out_proj_func(action_hidden_states: torch.FloatTensor) -> torch.FloatTensor:
+            with self.flow_head_autocast_context():
+                action_hidden_states = action_hidden_states.to(dtype=self.action_out_proj.dtype)
+                return self.action_out_proj(action_hidden_states)
+
+        v_t = self._apply_checkpoint(action_out_proj_func, action_hidden_states)
+        v_t = v_t.reshape(u_t.shape).to(dtype=u_t.dtype)
+        losses = F.mse_loss(u_t, v_t, reduction="none")
+
+        # 6. Apply the configured supervision mask and reduce the loss.
+        if not self.config.supervise_padding_action_dims:
+            original_action_dim = self.config.output_features[ACTION].shape[0]
+            losses = losses[..., :original_action_dim]
+
+        if not self.config.supervise_padding_actions:
+            losses = losses[~action_is_pad]
+
+        return losses.mean()
+
+    @torch.no_grad()
+    def sample_actions(
+        self,
+        input_ids: torch.LongTensor | None = None,
+        attention_mask: torch.Tensor | None = None,
+        pixel_values: torch.Tensor | None = None,
+        image_grid_thw: torch.LongTensor | None = None,
+        mm_token_type_ids: torch.IntTensor | None = None,
+        states: torch.Tensor | None = None,
+        *,
+        state_token_id: int,
+        action_token_id: int,
+        **kwargs,
+    ) -> Tensor:
+        """Sample actions from the model."""
+        if states is None:
+            raise ValueError("states are required for EO1 action sampling.")
+        if mm_token_type_ids is None:
+            raise ValueError("mm_token_type_ids are required for EO1 action sampling.")
+
+        # 1. Resolve the left-padded rollout prompt and locate the action span.
+        chunk_size = self.config.chunk_size
+
+        inputs_embeds = self.embed_prefix(
+            input_ids,
+            states=states,
+            state_token_id=state_token_id,
+            action_token_id=action_token_id,
+        ).clone()
+        _, action_placeholder_mask = self.get_placeholder_mask(
+            input_ids,
+            inputs_embeds,
+            state_token_id=state_token_id,
+            action_token_id=action_token_id,
+        )
+        action_mask = action_placeholder_mask[..., 0]
+        token_counts = action_mask.sum(dim=1)
+        if not torch.all(token_counts == chunk_size):
+            raise ValueError(
+                f"Each sample must contain exactly {chunk_size} action tokens, got {token_counts.tolist()}."
+            )
+        if action_mask.ne(action_mask[:1]).any():
+            raise ValueError(
+                "Batch inference expects all samples to share the same action token mask after left padding."
+            )
+        act_start = int(action_mask[0].to(torch.int64).argmax().item())
+        act_end = act_start + self.config.chunk_size
+        if not torch.all(action_mask[:, act_start:act_end]):
+            raise ValueError("Action tokens must form a contiguous chunk of length chunk_size.")
+        act_slice = slice(act_start, act_end)
+
+        # 2. Encode the fixed prefix once and cache its KV state.
+        batch_size = input_ids.shape[0]
+        device = inputs_embeds.device
+        attention_mask = attention_mask.to(device)
+        mm_token_type_ids = mm_token_type_ids.to(device)
+        position_ids, _ = self.vlm_backbone.model.get_rope_index(
+            input_ids,
+            image_grid_thw=image_grid_thw,
+            attention_mask=attention_mask,
+            mm_token_type_ids=mm_token_type_ids,
+        )
+        position_ids = position_ids.to(device)
+
+        outputs = self.vlm_backbone.model(
+            input_ids=input_ids[:, :act_start],
+            attention_mask=attention_mask[:, :act_start],
+            position_ids=position_ids[..., :act_start],
+            inputs_embeds=inputs_embeds[:, :act_start],
+            pixel_values=pixel_values,
+            image_grid_thw=image_grid_thw,
+            mm_token_type_ids=mm_token_type_ids[:, :act_start],
+            use_cache=True,
+            return_dict=True,
+        )
+
+        x_t = self.sample_noise(
+            (batch_size, chunk_size, self.config.max_action_dim),
+            device,
+        ).to(dtype=self.action_in_proj.weight.dtype)
+        dt = -1.0 / self.config.num_denoise_steps
+        past_key_values = outputs.past_key_values
+
+        # 3. Denoise only the action chunk while keeping the prefix cache invariant.
+        for step in range(self.config.num_denoise_steps):
+            time = torch.full(
+                (batch_size,),
+                1.0 + step * dt,
+                device=device,
+                dtype=torch.float32,
+            )
+            action_time_embs = self.embed_suffix(time, x_t)
+            inputs_embeds[:, act_slice] = action_time_embs.to(inputs_embeds.dtype)
+
+            # Keep the prefix KV cache invariant across denoising steps.
+            past_key_values.crop(act_start)
+            outputs = self.vlm_backbone.model(
+                attention_mask=attention_mask[:, :act_end],
+                past_key_values=past_key_values,
+                inputs_embeds=inputs_embeds[:, act_slice],
+                position_ids=position_ids[..., act_slice],
+                use_cache=True,
+                return_dict=True,
+            )
+            with self.flow_head_autocast_context():
+                hidden_states = outputs.last_hidden_state[:, :chunk_size]
+                hidden_states = hidden_states.to(dtype=self.action_out_proj.dtype)
+                v_t = self.action_out_proj(hidden_states)
+
+            x_t += dt * v_t.reshape(x_t.shape)
+
+        return x_t

src/lerobot/policies/eo1/processor_eo1.py

@@ -0,0 +1,282 @@
+#!/usr/bin/env python
+
+# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from typing import TYPE_CHECKING, Any
+
+import torch
+
+from lerobot.configs.types import FeatureType, PipelineFeatureType, PolicyFeature
+from lerobot.policies.eo1.configuration_eo1 import EO1Config
+from lerobot.processor import (
+    AddBatchDimensionProcessorStep,
+    ComplementaryDataProcessorStep,
+    DeviceProcessorStep,
+    NormalizerProcessorStep,
+    PolicyAction,
+    PolicyProcessorPipeline,
+    ProcessorStep,
+    ProcessorStepRegistry,
+    RenameObservationsProcessorStep,
+    UnnormalizerProcessorStep,
+)
+from lerobot.processor.converters import policy_action_to_transition, transition_to_policy_action
+from lerobot.types import TransitionKey
+from lerobot.utils.constants import (
+    OBS_STATE,
+    POLICY_POSTPROCESSOR_DEFAULT_NAME,
+    POLICY_PREPROCESSOR_DEFAULT_NAME,
+)
+from lerobot.utils.import_utils import _transformers_available, require_package
+
+if TYPE_CHECKING or _transformers_available:
+    from transformers.models.qwen2_5_vl import Qwen2_5_VLProcessor
+else:
+    Qwen2_5_VLProcessor = None
+
+SYSTEM_MESSAGE = "You are a helpful physical assistant."
+
+# EO-1 special tokens
+ACTION_START_TOKEN = "<|action_start|>"  # nosec B105
+DEFAULT_ACTION_TOKEN = "<|action_pad|>"  # nosec B105
+ACTION_END_TOKEN = "<|action_end|>"  # nosec B105
+STATE_START_TOKEN = "<|state_start|>"  # nosec B105
+DEFAULT_STATE_TOKEN = "<|state_pad|>"  # nosec B105
+STATE_END_TOKEN = "<|state_end|>"  # nosec B105
+TASK_VLA_TOKEN = "<|vla|>"  # nosec B105
+
+EO1_SPECIAL_TOKENS = [
+    ACTION_START_TOKEN,
+    DEFAULT_ACTION_TOKEN,
+    ACTION_END_TOKEN,
+    STATE_START_TOKEN,
+    DEFAULT_STATE_TOKEN,
+    STATE_END_TOKEN,
+    TASK_VLA_TOKEN,
+]
+
+
+@dataclass
+@ProcessorStepRegistry.register(name="eo1_conversation_template_processor")
+class EO1ConversationTemplateStep(ComplementaryDataProcessorStep):
+    input_features: dict[str, PolicyFeature] | dict[str, dict[str, Any]]
+    chunk_size: int
+
+    _image_keys: list[str] = field(default_factory=list, init=False, repr=False)
+
+    def __post_init__(self):
+        # Robust JSON deserialization handling (guard empty maps).
+        if self.input_features:
+            first_val = next(iter(self.input_features.values()))
+            if isinstance(first_val, dict):
+                reconstructed = {}
+                for key, ft_dict in self.input_features.items():
+                    reconstructed[key] = PolicyFeature(
+                        type=FeatureType(ft_dict["type"]), shape=tuple(ft_dict["shape"])
+                    )
+                self.input_features = reconstructed
+
+        self._image_keys = [
+            key for key, value in self.input_features.items() if value.type == FeatureType.VISUAL
+        ]
+
+    def complementary_data(self, complementary_data):
+        tasks = complementary_data.get("task")
+        if tasks is None:
+            raise ValueError("Task is required for EO1ConversationTemplateStep.")
+
+        observation = self.transition.get(TransitionKey.OBSERVATION)
+        if observation is None:
+            raise ValueError("Observation is required for EO1ConversationTemplateStep.")
+
+        if OBS_STATE in observation and observation[OBS_STATE].shape[0] != len(tasks):
+            raise ValueError("Batch size mismatch between observation.state and task list.")
+
+        # LeRobot visual observations reach in processor as float32 tensors in [0, 1].
+        # Convert to uint8 in [0, 255] to meet the input requirement of Qwen2.5-VL-3B-Instruct.
+        images = {
+            key: observation[key].clamp(0, 1).mul(255.0).round().to(torch.uint8) for key in self._image_keys
+        }
+        messages = []
+        for i in range(len(tasks)):
+            content = [
+                *[{"type": "image", "image": images[key][i]} for key in self._image_keys],
+                {
+                    "type": "text",
+                    "text": (
+                        f"{STATE_START_TOKEN}{DEFAULT_STATE_TOKEN}{STATE_END_TOKEN}{tasks[i]}{TASK_VLA_TOKEN}"
+                    ),
+                },
+            ]
+            messages.append(
+                [
+                    {"role": "system", "content": [{"type": "text", "text": SYSTEM_MESSAGE}]},
+                    {"role": "user", "content": content},
+                    {
+                        "role": "assistant",
+                        "content": [
+                            {
+                                "type": "text",
+                                "text": f"{ACTION_START_TOKEN}{DEFAULT_ACTION_TOKEN * self.chunk_size}{ACTION_END_TOKEN}",
+                            }
+                        ],
+                    },
+                ]
+            )
+
+        complementary_data["messages"] = messages
+
+        return complementary_data
+
+    def transform_features(
+        self, features: dict[PipelineFeatureType, dict[str, PolicyFeature]]
+    ) -> dict[PipelineFeatureType, dict[str, PolicyFeature]]:
+        """
+        This step only materializes EO1-specific message objects in complementary_data.
+        PipelineFeatureType tracks only ACTION and OBSERVATION, so there is no static
+        feature contract change to record here.
+        """
+        return features
+
+    def get_config(self) -> dict[str, Any]:
+        return {
+            "input_features": {
+                key: {"type": ft.type.value, "shape": ft.shape} for key, ft in self.input_features.items()
+            },
+            "chunk_size": self.chunk_size,
+        }
+
+
+@dataclass
+@ProcessorStepRegistry.register(name="eo1_qwen_processor")
+class EO1QwenProcessorStep(ComplementaryDataProcessorStep):
+    processor_name: str = "Qwen/Qwen2.5-VL-3B-Instruct"
+    image_min_pixels: int | None = 64 * 28 * 28
+    image_max_pixels: int | None = 128 * 28 * 28
+    use_fast_processor: bool = False
+
+    _processor: Qwen2_5_VLProcessor | None = field(default=None, init=False, repr=False)
+    _state_token_id: int | None = field(default=None, init=False, repr=False)
+    _action_token_id: int | None = field(default=None, init=False, repr=False)
+
+    def __post_init__(self):
+        require_package("transformers", extra="eo1")
+        self._processor = Qwen2_5_VLProcessor.from_pretrained(
+            self.processor_name,
+            use_fast=self.use_fast_processor,
+        )
+        self._processor.tokenizer.add_tokens(EO1_SPECIAL_TOKENS, special_tokens=True)
+        self._state_token_id = self._processor.tokenizer.convert_tokens_to_ids(DEFAULT_STATE_TOKEN)
+        self._action_token_id = self._processor.tokenizer.convert_tokens_to_ids(DEFAULT_ACTION_TOKEN)
+
+    def complementary_data(self, complementary_data):
+        messages = complementary_data.pop("messages", None)
+        if messages is None:
+            raise ValueError("Messages are required for EO1QwenProcessorStep.")
+
+        # Rollout batches use left padding so action spans stay aligned across samples.
+        # Supervised batches use right padding to match standard training collation.
+        padding_side = "right" if self.transition.get(TransitionKey.ACTION) is not None else "left"
+
+        inputs = self._processor.apply_chat_template(
+            messages,
+            tokenize=True,
+            padding=True,
+            padding_side=padding_side,
+            min_pixels=self.image_min_pixels,
+            max_pixels=self.image_max_pixels,
+            add_generation_prompt=False,
+            return_dict=True,
+            return_tensors="pt",
+        )
+
+        complementary_data["input_ids"] = inputs["input_ids"]
+        complementary_data["pixel_values"] = inputs["pixel_values"]
+        complementary_data["image_grid_thw"] = inputs["image_grid_thw"]
+        complementary_data["attention_mask"] = inputs["attention_mask"]
+        complementary_data["mm_token_type_ids"] = inputs["mm_token_type_ids"]
+        complementary_data["state_token_id"] = self._state_token_id
+        complementary_data["action_token_id"] = self._action_token_id
+
+        return complementary_data
+
+    def get_config(self) -> dict[str, Any]:
+        return {
+            "processor_name": self.processor_name,
+            "image_min_pixels": self.image_min_pixels,
+            "image_max_pixels": self.image_max_pixels,
+            "use_fast_processor": self.use_fast_processor,
+        }
+
+    def transform_features(
+        self, features: dict[PipelineFeatureType, dict[str, PolicyFeature]]
+    ) -> dict[PipelineFeatureType, dict[str, PolicyFeature]]:
+        """
+        This step only converts the messages to the model input format.
+        """
+        return features
+
+
+def make_eo1_pre_post_processors(
+    config: EO1Config,
+    dataset_stats: dict[str, dict[str, torch.Tensor]] | None = None,
+) -> tuple[
+    PolicyProcessorPipeline[dict[str, Any], dict[str, Any]],
+    PolicyProcessorPipeline[PolicyAction, PolicyAction],
+]:
+    """Build pre/post processor pipelines for EO1."""
+
+    input_steps: list[ProcessorStep] = [
+        RenameObservationsProcessorStep(rename_map={}),
+        AddBatchDimensionProcessorStep(),
+        NormalizerProcessorStep(
+            features={**config.input_features, **config.output_features},
+            norm_map=config.normalization_mapping,
+            stats=dataset_stats,
+        ),
+        EO1ConversationTemplateStep(input_features=config.input_features, chunk_size=config.chunk_size),
+        EO1QwenProcessorStep(
+            processor_name=config.vlm_base,
+            image_min_pixels=config.image_min_pixels,
+            image_max_pixels=config.image_max_pixels,
+            use_fast_processor=config.use_fast_processor,
+        ),
+        DeviceProcessorStep(device=config.device),
+    ]
+
+    output_steps: list[ProcessorStep] = [
+        UnnormalizerProcessorStep(
+            features=config.output_features,
+            norm_map=config.normalization_mapping,
+            stats=dataset_stats,
+        ),
+        DeviceProcessorStep(device="cpu"),
+    ]
+
+    return (
+        PolicyProcessorPipeline[dict[str, Any], dict[str, Any]](
+            steps=input_steps,
+            name=POLICY_PREPROCESSOR_DEFAULT_NAME,
+        ),
+        PolicyProcessorPipeline[PolicyAction, PolicyAction](
+            steps=output_steps,
+            name=POLICY_POSTPROCESSOR_DEFAULT_NAME,
+            to_transition=policy_action_to_transition,
+            to_output=transition_to_policy_action,
+        ),
+    )

src/lerobot/policies/factory.py

@@ -46,14 +46,13 @@ from lerobot.utils.feature_utils import dataset_to_policy_features
 
 from .act.configuration_act import ACTConfig
 from .diffusion.configuration_diffusion import DiffusionConfig
+from .eo1.configuration_eo1 import EO1Config
 from .groot.configuration_groot import GrootConfig
 from .multi_task_dit.configuration_multi_task_dit import MultiTaskDiTConfig
 from .pi0.configuration_pi0 import PI0Config
 from .pi05.configuration_pi05 import PI05Config
 from .pretrained import PreTrainedPolicy
 from .sac.configuration_sac import SACConfig
-from .sac.reward_model.configuration_classifier import RewardClassifierConfig
-from .sarm.configuration_sarm import SARMConfig
 from .smolvla.configuration_smolvla import SmolVLAConfig
 from .tdmpc.configuration_tdmpc import TDMPCConfig
 from .utils import validate_visual_features_consistency
@@ -89,7 +88,7 @@ def get_policy_class(name: str) -> type[PreTrainedPolicy]:
 
     Args:
         name: The name of the policy. Supported names are "tdmpc", "diffusion", "act",
-            "multi_task_dit", "vqbet", "pi0", "pi05", "sac", "reward_classifier", "smolvla", "wall_x".
+            "multi_task_dit", "vqbet", "pi0", "pi05", "sac", "smolvla", "wall_x".
     Returns:
         The policy class corresponding to the given name.
 
@@ -132,18 +131,10 @@ def get_policy_class(name: str) -> type[PreTrainedPolicy]:
         from .sac.modeling_sac import SACPolicy
 
         return SACPolicy
-    elif name == "reward_classifier":
-        from .sac.reward_model.modeling_classifier import Classifier
-
-        return Classifier
     elif name == "smolvla":
         from .smolvla.modeling_smolvla import SmolVLAPolicy
 
         return SmolVLAPolicy
-    elif name == "sarm":
-        from .sarm.modeling_sarm import SARMRewardModel
-
-        return SARMRewardModel
     elif name == "groot":
         from .groot.modeling_groot import GrootPolicy
 
@@ -156,6 +147,10 @@ def get_policy_class(name: str) -> type[PreTrainedPolicy]:
         from .wall_x.modeling_wall_x import WallXPolicy
 
         return WallXPolicy
+    elif name == "eo1":
+        from .eo1.modeling_eo1 import EO1Policy
+
+        return EO1Policy
     else:
         try:
             return _get_policy_cls_from_policy_name(name=name)
@@ -173,7 +168,7 @@ def make_policy_config(policy_type: str, **kwargs) -> PreTrainedConfig:
     Args:
         policy_type: The type of the policy. Supported types include "tdmpc",
                      "multi_task_dit", "diffusion", "act", "vqbet", "pi0", "pi05", "sac",
-                     "smolvla", "reward_classifier", "wall_x".
+                     "smolvla", "wall_x".
         **kwargs: Keyword arguments to be passed to the configuration class constructor.
 
     Returns:
@@ -200,14 +195,14 @@ def make_policy_config(policy_type: str, **kwargs) -> PreTrainedConfig:
         return SACConfig(**kwargs)
     elif policy_type == "smolvla":
         return SmolVLAConfig(**kwargs)
-    elif policy_type == "reward_classifier":
-        return RewardClassifierConfig(**kwargs)
     elif policy_type == "groot":
         return GrootConfig(**kwargs)
     elif policy_type == "xvla":
         return XVLAConfig(**kwargs)
     elif policy_type == "wall_x":
         return WallXConfig(**kwargs)
+    elif policy_type == "eo1":
+        return EO1Config(**kwargs)
     else:
         try:
             config_cls = PreTrainedConfig.get_choice_class(policy_type)
@@ -378,14 +373,6 @@ def make_pre_post_processors(
             dataset_stats=kwargs.get("dataset_stats"),
         )
 
-    elif isinstance(policy_cfg, RewardClassifierConfig):
-        from .sac.reward_model.processor_classifier import make_classifier_processor
-
-        processors = make_classifier_processor(
-            config=policy_cfg,
-            dataset_stats=kwargs.get("dataset_stats"),
-        )
-
     elif isinstance(policy_cfg, SmolVLAConfig):
         from .smolvla.processor_smolvla import make_smolvla_pre_post_processors
 
@@ -394,14 +381,6 @@ def make_pre_post_processors(
             dataset_stats=kwargs.get("dataset_stats"),
         )
 
-    elif isinstance(policy_cfg, SARMConfig):
-        from .sarm.processor_sarm import make_sarm_pre_post_processors
-
-        processors = make_sarm_pre_post_processors(
-            config=policy_cfg,
-            dataset_stats=kwargs.get("dataset_stats"),
-            dataset_meta=kwargs.get("dataset_meta"),
-        )
     elif isinstance(policy_cfg, GrootConfig):
         from .groot.processor_groot import make_groot_pre_post_processors
 
@@ -427,6 +406,13 @@ def make_pre_post_processors(
             config=policy_cfg,
             dataset_stats=kwargs.get("dataset_stats"),
         )
+    elif isinstance(policy_cfg, EO1Config):
+        from .eo1.processor_eo1 import make_eo1_pre_post_processors
+
+        processors = make_eo1_pre_post_processors(
+            config=policy_cfg,
+            dataset_stats=kwargs.get("dataset_stats"),
+        )
 
     else:
         try:
@@ -542,7 +528,7 @@ def make_policy(
 
         logging.info("Loading policy's PEFT adapter.")
 
-        peft_pretrained_path = cfg.pretrained_path
+        peft_pretrained_path = str(cfg.pretrained_path)
         peft_config = PeftConfig.from_pretrained(peft_pretrained_path)
 
         kwargs["pretrained_name_or_path"] = peft_config.base_model_name_or_path
@@ -555,7 +541,9 @@ def make_policy(
             )
 
         policy = policy_cls.from_pretrained(**kwargs)
-        policy = PeftModel.from_pretrained(policy, peft_pretrained_path, config=peft_config)
+        policy = PeftModel.from_pretrained(
+            policy, peft_pretrained_path, config=peft_config, is_trainable=True
+        )
 
     else:
         # Make a fresh policy.

src/lerobot/policies/groot/action_head/flow_matching_action_head.py

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from dataclasses import dataclass, field
+from dataclasses import field
 from typing import TYPE_CHECKING
 
 import torch
@@ -109,7 +109,6 @@ class MultiEmbodimentActionEncoder(nn.Module):
         return x
 
 
-@dataclass
 class FlowmatchingActionHeadConfig(PretrainedConfig):
     """NOTE: N1.5 uses XEmbFlowmatchingPolicyHeadConfig as action head"""
 

src/lerobot/policies/groot/groot_n1.py

@@ -13,7 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from dataclasses import dataclass, field
 from pathlib import Path
 from typing import TYPE_CHECKING
 
@@ -174,17 +173,14 @@ N_COLOR_CHANNELS = 3
 
 
 # config
-@dataclass
 class GR00TN15Config(PretrainedConfig):
     model_type = "gr00t_n1_5"
-    backbone_cfg: dict = field(init=False, metadata={"help": "Backbone configuration."})
 
-    action_head_cfg: dict = field(init=False, metadata={"help": "Action head configuration."})
-
-    action_horizon: int = field(init=False, metadata={"help": "Action horizon."})
-
-    action_dim: int = field(init=False, metadata={"help": "Action dimension."})
-    compute_dtype: str = field(default="float32", metadata={"help": "Compute dtype."})
+    backbone_cfg: dict
+    action_head_cfg: dict
+    action_horizon: int
+    action_dim: int
+    compute_dtype: str = "float32"
 
     def __init__(self, **kwargs):
         super().__init__(**kwargs)

src/lerobot/policies/multi_task_dit/modeling_multi_task_dit.py

@@ -688,8 +688,9 @@ class DiffusionObjective(nn.Module):
         loss = F.mse_loss(predicted, target, reduction="none")
 
         if self.do_mask_loss_for_padding and "action_is_pad" in batch:
-            valid_actions = ~batch["action_is_pad"]
-            loss = loss * valid_actions.unsqueeze(-1)
+            mask = ~batch["action_is_pad"].unsqueeze(-1)
+            num_valid = mask.sum() * loss.shape[-1]
+            return (loss * mask).sum() / num_valid.clamp_min(1)
 
         return loss.mean()
 
@@ -752,8 +753,9 @@ class FlowMatchingObjective(nn.Module):
         loss = F.mse_loss(predicted_velocity, target_velocity, reduction="none")
 
         if self.do_mask_loss_for_padding and "action_is_pad" in batch:
-            valid_mask = ~batch["action_is_pad"]
-            loss = loss * valid_mask.unsqueeze(-1)
+            mask = ~batch["action_is_pad"].unsqueeze(-1)
+            num_valid = mask.sum() * loss.shape[-1]
+            return (loss * mask).sum() / num_valid.clamp_min(1)
 
         return loss.mean()
 

src/lerobot/policies/pi0/modeling_pi0.py

@@ -444,13 +444,13 @@ class PaliGemmaWithExpertModel(
         if image.dtype != torch.float32:
             image = image.to(torch.float32)
         image_outputs = self.paligemma.model.get_image_features(image)
-        features = image_outputs.pooler_output * self.paligemma.config.text_config.hidden_size**0.5
+        features = image_outputs.pooler_output
         if features.dtype != out_dtype:
             features = features.to(out_dtype)
         return features
 
     def embed_language_tokens(self, tokens: torch.Tensor):
-        return self.paligemma.model.language_model.embed_tokens(tokens)
+        return self.paligemma.model.language_model.get_input_embeddings()(tokens)
 
     def forward(
         self,
@@ -666,8 +666,7 @@ class PI0Pytorch(nn.Module):  # see openpi `PI0Pytorch`
         # Process language tokens
         def lang_embed_func(lang_tokens):
             lang_emb = self.paligemma_with_expert.embed_language_tokens(lang_tokens)
-            lang_emb_dim = lang_emb.shape[-1]
-            return lang_emb * math.sqrt(lang_emb_dim)
+            return lang_emb
 
         lang_emb = self._apply_checkpoint(lang_embed_func, lang_tokens)
         embs.append(lang_emb)
@@ -748,16 +747,8 @@ class PI0Pytorch(nn.Module):  # see openpi `PI0Pytorch`
 
         return embs, pad_masks, att_masks, adarms_cond
 
-    def forward(
-        self, images, img_masks, lang_tokens, lang_masks, state, actions, noise=None, time=None
-    ) -> Tensor:
+    def forward(self, images, img_masks, lang_tokens, lang_masks, state, actions, noise, time) -> Tensor:
         """Do a full training forward pass and compute the loss."""
-        if noise is None:
-            noise = self.sample_noise(actions.shape, actions.device)
-
-        if time is None:
-            time = self.sample_time(actions.shape[0], actions.device)
-
         time_expanded = time[:, None, None]
         x_t = time_expanded * noise + (1 - time_expanded) * actions
         u_t = noise - actions
@@ -1292,8 +1283,11 @@ class PI0Policy(PreTrainedPolicy):
         state = self.prepare_state(batch)
         actions = self.prepare_action(batch)
 
+        noise = self.model.sample_noise(actions.shape, actions.device)
+        time = self.model.sample_time(actions.shape[0], actions.device)
+
         # Compute loss
-        losses = self.model.forward(images, img_masks, lang_tokens, lang_masks, state, actions)
+        losses = self.model.forward(images, img_masks, lang_tokens, lang_masks, state, actions, noise, time)
 
         # Truncate losses to actual action dimensions
         original_action_dim = self.config.output_features[ACTION].shape[0]

src/lerobot/policies/pi05/modeling_pi05.py

@@ -728,14 +728,8 @@ class PI05Pytorch(nn.Module):  # see openpi `PI0Pytorch`
 
         return embs, pad_masks, att_masks, adarms_cond
 
-    def forward(self, images, img_masks, tokens, masks, actions, noise=None, time=None) -> Tensor:
+    def forward(self, images, img_masks, tokens, masks, actions, noise, time) -> Tensor:
         """Do a full training forward pass and compute the loss."""
-        if noise is None:
-            noise = self.sample_noise(actions.shape, actions.device)
-
-        if time is None:
-            time = self.sample_time(actions.shape[0], actions.device)
-
         time_expanded = time[:, None, None]
         x_t = time_expanded * noise + (1 - time_expanded) * actions
         u_t = noise - actions
@@ -1262,8 +1256,11 @@ class PI05Policy(PreTrainedPolicy):
 
         actions = self.prepare_action(batch)
 
+        noise = self.model.sample_noise(actions.shape, actions.device)
+        time = self.model.sample_time(actions.shape[0], actions.device)
+
         # Compute loss (no separate state needed for PI05)
-        losses = self.model.forward(images, img_masks, tokens, masks, actions)
+        losses = self.model.forward(images, img_masks, tokens, masks, actions, noise, time)
 
         # Truncate losses to actual action dimensions
         original_action_dim = self.config.output_features[ACTION].shape[0]

src/lerobot/policies/pi0_fast/modeling_pi0_fast.py

@@ -16,7 +16,6 @@
 
 import builtins
 import logging
-import math
 from collections import deque
 from pathlib import Path
 from typing import TYPE_CHECKING, Literal, TypedDict, Unpack
@@ -227,6 +226,7 @@ class PI0FastPaliGemma(nn.Module):
         # forward(..., adarms_cond=...) is supported (same as pi0/pi05).
         if use_adarms[0]:
             text_config = self.paligemma.config.text_config
+            del self.paligemma.model.language_model
             self.paligemma.model.language_model = PiGemmaModel(text_config)
 
         self.to_bfloat16_for_selected_params(precision)
@@ -260,13 +260,15 @@ class PI0FastPaliGemma(nn.Module):
         if image.dtype != torch.float32:
             image = image.to(torch.float32)
         image_outputs = self.paligemma.model.get_image_features(image)
-        features = image_outputs.pooler_output * self.paligemma.config.text_config.hidden_size**0.5
+        features = image_outputs.pooler_output
+        norm = 2048**0.5
+        features = features / norm * norm
         if features.dtype != out_dtype:
             features = features.to(out_dtype)
         return features
 
     def embed_language_tokens(self, tokens: torch.Tensor):
-        return self.paligemma.model.language_model.embed_tokens(tokens)
+        return self.paligemma.model.language_model.get_input_embeddings()(tokens)
 
     def forward(
         self,
@@ -416,8 +418,7 @@ class PI0FastPytorch(nn.Module):  # see openpi `PI0Pytorch`
         # Process language instruction tokens
         def lang_embed_func(tokens):
             lang_emb = self.paligemma_with_expert.embed_language_tokens(tokens)
-            lang_emb_dim = lang_emb.shape[-1]
-            return lang_emb * math.sqrt(lang_emb_dim)
+            return lang_emb
 
         lang_emb = self._apply_checkpoint(lang_embed_func, tokens)
         embs.append(lang_emb)
@@ -431,8 +432,7 @@ class PI0FastPytorch(nn.Module):  # see openpi `PI0Pytorch`
 
             def fast_action_embed_func(fast_action_tokens):
                 fast_emb = self.paligemma_with_expert.embed_language_tokens(fast_action_tokens)
-                fast_emb_dim = fast_emb.shape[-1]
-                return fast_emb * math.sqrt(fast_emb_dim)
+                return fast_emb
 
             fast_action_emb = self._apply_checkpoint(fast_action_embed_func, fast_action_tokens)
             embs.append(fast_action_emb)
@@ -665,7 +665,6 @@ class PI0FastPytorch(nn.Module):  # see openpi `PI0Pytorch`
             if t < max_decoding_steps - 1:
                 # embed the newly generated token
                 next_token_emb = self.paligemma_with_expert.embed_language_tokens(next_token)
-                next_token_emb = next_token_emb * math.sqrt(next_token_emb.shape[-1])
                 if prefix_embs.dtype == torch.bfloat16:
                     next_token_emb = next_token_emb.to(dtype=torch.bfloat16)
 
@@ -770,7 +769,6 @@ class PI0FastPytorch(nn.Module):  # see openpi `PI0Pytorch`
             # Embed the single previous token
             # We use embed_language_tokens directly to avoid overhead of full prefix embedding
             next_token_emb = self.paligemma_with_expert.embed_language_tokens(next_token)
-            next_token_emb = next_token_emb * math.sqrt(next_token_emb.shape[-1])
             if prefix_embs.dtype == torch.bfloat16:
                 next_token_emb = next_token_emb.to(dtype=torch.bfloat16)
 

src/lerobot/policies/pi_gemma.py

@@ -197,6 +197,9 @@ class PiGemmaModel(GemmaModel):  # type: ignore[misc]
 
     def __init__(self, config: GemmaConfig, **kwargs):
         super().__init__(config, **kwargs)
+        # Free parent-allocated layers/norm before replacing to avoid ~2x peak memory.
+        del self.layers
+        del self.norm
         # if not getattr(config, "use_adarms", False):
         #     return
         cond_dim = getattr(config, "adarms_cond_dim", None)
@@ -328,6 +331,7 @@ class PiGemmaForCausalLM(GemmaForCausalLM):  # type: ignore[misc]
 
     def __init__(self, config: GemmaConfig, **kwargs):
         super().__init__(config, **kwargs)
+        del self.model
         self.model = PiGemmaModel(config)
 
 
@@ -336,6 +340,7 @@ class PaliGemmaModelWithPiGemma(PaliGemmaModel):
 
     def __init__(self, config):
         super().__init__(config)
+        del self.language_model
         self.language_model = PiGemmaModel(config.text_config)
 
 
@@ -344,6 +349,7 @@ class PaliGemmaForConditionalGenerationWithPiGemma(PaliGemmaForConditionalGenera
 
     def __init__(self, config):
         super().__init__(config)
+        del self.model
         self.model = PaliGemmaModelWithPiGemma(config)
 
     # Make modules available through conditional class for BC

src/lerobot/policies/rtc/__init__.py

@@ -19,6 +19,7 @@ from .action_queue import ActionQueue
 from .configuration_rtc import RTCConfig
 from .latency_tracker import LatencyTracker
 from .modeling_rtc import RTCProcessor
+from .relative import reanchor_relative_rtc_prefix
 
 __all__ = [
     "ActionInterpolator",
@@ -26,4 +27,5 @@ __all__ = [
     "LatencyTracker",
     "RTCConfig",
     "RTCProcessor",
+    "reanchor_relative_rtc_prefix",
 ]

src/lerobot/policies/rtc/relative.py

@@ -0,0 +1,58 @@
+#!/usr/bin/env python
+
+# Copyright 2025 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Relative-action helpers for Real-Time Chunking (RTC)."""
+
+from __future__ import annotations
+
+import torch
+
+from lerobot.processor import (
+    NormalizerProcessorStep,
+    RelativeActionsProcessorStep,
+    TransitionKey,
+    create_transition,
+    to_relative_actions,
+)
+
+
+def reanchor_relative_rtc_prefix(
+    prev_actions_absolute: torch.Tensor,
+    current_state: torch.Tensor,
+    relative_step: RelativeActionsProcessorStep,
+    normalizer_step: NormalizerProcessorStep | None,
+    policy_device: torch.device | str,
+) -> torch.Tensor:
+    """Convert absolute leftover actions into model-space for relative-action RTC policies.
+
+    When using relative actions, the RTC prefix (previous chunk's unexecuted tail)
+    is stored in absolute coordinates. Before feeding it back to the policy, this
+    helper re-expresses those actions relative to the robot's current joint state
+    and optionally normalizes them so the policy receives correctly scaled inputs.
+    """
+    state = current_state.detach().cpu()
+    if state.dim() == 1:
+        state = state.unsqueeze(0)
+
+    action_cpu = prev_actions_absolute.detach().cpu()
+    mask = relative_step._build_mask(action_cpu.shape[-1])
+    relative_actions = to_relative_actions(action_cpu, state, mask)
+
+    transition = create_transition(action=relative_actions)
+    if normalizer_step is not None:
+        transition = normalizer_step(transition)
+
+    return transition[TransitionKey.ACTION].to(policy_device)

src/lerobot/policies/sarm/README.md

@@ -1 +0,0 @@
-../../../../docs/source/policy_sarm_README.md

src/lerobot/policies/smolvla/modeling_smolvla.py

@@ -394,13 +394,21 @@ class SmolVLAPolicy(PreTrainedPolicy):
         loss_dict["losses_after_rm_padding"] = losses.clone().mean().item()
 
         if reduction == "none":
-            # Return per-sample losses (B,) by averaging over time and action dims
-            per_sample_loss = losses.mean(dim=(1, 2))
+            # Return per-sample losses (B,) by averaging over valid (time, action) entries
+            if actions_is_pad is None:
+                per_sample_loss = losses.mean(dim=(1, 2))
+            else:
+                num_valid = ((~actions_is_pad).sum(dim=1) * losses.shape[-1]).clamp_min(1)
+                per_sample_loss = losses.sum(dim=(1, 2)) / num_valid
             loss_dict["loss"] = per_sample_loss.mean().item()
             return per_sample_loss, loss_dict
         else:
-            # Default: return scalar mean loss
-            loss = losses.mean()
+            # Default: return scalar mean loss over valid (time, action) entries
+            if actions_is_pad is None:
+                loss = losses.mean()
+            else:
+                num_valid = ((~actions_is_pad).sum() * losses.shape[-1]).clamp_min(1)
+                loss = losses.sum() / num_valid
             loss_dict["loss"] = loss.item()
             return loss, loss_dict
 

src/lerobot/policies/wall_x/qwen_model/qwen2_5_vl_moe.py

@@ -22,7 +22,7 @@ from transformers.utils import (
     add_start_docstrings,
     add_start_docstrings_to_model_forward,
     is_flash_attn_2_available,
-    is_flash_attn_greater_or_equal_2_10,
+    is_flash_attn_greater_or_equal,
     is_torchdynamo_compiling,
     logging,
     replace_return_docstrings,
@@ -890,7 +890,7 @@ class Qwen2_5_VLFlashAttention2(Qwen2_5_VLAttention):
         # TODO: Should be removed once Flash Attention for RoCm is bumped to 2.1.
         # flash_attn<2.1 generates top-left aligned causal mask, while what is needed here is bottom-right alignment, that was made default for flash_attn>=2.1. This attribute is used to handle this difference. Reference: https://github.com/Dao-AILab/flash-attention/releases/tag/v2.1.0.
         # Beware that with flash_attn<2.1, using q_seqlen != k_seqlen (except for the case q_seqlen == 1) produces a wrong mask (top-left).
-        self._flash_attn_uses_top_left_mask = not is_flash_attn_greater_or_equal_2_10()
+        self._flash_attn_uses_top_left_mask = not is_flash_attn_greater_or_equal("2.1.0")
 
     def forward(
         self,

src/lerobot/policies/xvla/modeling_florence2.py

@@ -45,7 +45,7 @@ from transformers.utils import (
     add_start_docstrings,
     add_start_docstrings_to_model_forward,
     is_flash_attn_2_available,
-    is_flash_attn_greater_or_equal_2_10,
+    is_flash_attn_greater_or_equal,
     logging,
     replace_return_docstrings,
 )
@@ -909,7 +909,7 @@ class Florence2FlashAttention2(Florence2Attention):
         # TODO: Should be removed once Flash Attention for RoCm is bumped to 2.1.
         # flash_attn<2.1 generates top-left aligned causal mask, while what is needed here is bottom-right alignment, that was made default for flash_attn>=2.1. This attribute is used to handle this difference. Reference: https://github.com/Dao-AILab/flash-attention/releases/tag/v2.1.0.
         # Beware that with flash_attn<2.1, using q_seqlen != k_seqlen (except for the case q_seqlen == 1) produces a wrong mask (top-left).
-        self._flash_attn_uses_top_left_mask = not is_flash_attn_greater_or_equal_2_10()
+        self._flash_attn_uses_top_left_mask = not is_flash_attn_greater_or_equal("2.1.0")
 
     def _reshape(self, tensor: torch.Tensor, seq_len: int, bsz: int):
         return tensor.view(bsz, seq_len, self.num_heads, self.head_dim)

src/lerobot/processor/hil_processor.py

@@ -557,7 +557,7 @@ class RewardClassifierProcessorStep(ProcessorStep):
     def __post_init__(self):
         """Initializes the reward classifier model after the dataclass is created."""
         if self.pretrained_path is not None:
-            from lerobot.policies.sac.reward_model.modeling_classifier import Classifier
+            from lerobot.rewards.classifier.modeling_classifier import Classifier
 
             self.reward_classifier = Classifier.from_pretrained(self.pretrained_path)
             self.reward_classifier.to(self.device)

src/lerobot/processor/relative_action_processor.py

@@ -142,6 +142,10 @@ class RelativeActionsProcessorStep(ProcessorStep):
         new_transition[TransitionKey.ACTION] = to_relative_actions(action, state, mask)
         return new_transition
 
+    def get_cached_state(self) -> torch.Tensor | None:
+        """Return the cached ``observation.state`` used as the reference point for relative/absolute action conversions."""
+        return self._last_state
+
     def get_config(self) -> dict[str, Any]:
         return {
             "enabled": self.enabled,
@@ -182,7 +186,8 @@ class AbsoluteActionsProcessorStep(ProcessorStep):
                 "but relative_step is None. Ensure relative_step is set when constructing the postprocessor."
             )
 
-        if self.relative_step._last_state is None:
+        cached_state = self.relative_step.get_cached_state()
+        if cached_state is None:
             raise RuntimeError(
                 "AbsoluteActionsProcessorStep requires state from RelativeActionsProcessorStep "
                 "but no state has been cached. Ensure the preprocessor runs before the postprocessor."
@@ -194,9 +199,7 @@ class AbsoluteActionsProcessorStep(ProcessorStep):
             return new_transition
 
         mask = self.relative_step._build_mask(action.shape[-1])
-        new_transition[TransitionKey.ACTION] = to_absolute_actions(
-            action, self.relative_step._last_state, mask
-        )
+        new_transition[TransitionKey.ACTION] = to_absolute_actions(action, cached_state, mask)
         return new_transition
 
     def get_config(self) -> dict[str, Any]:

src/lerobot/rewards/__init__.py

@@ -0,0 +1,36 @@
+# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from .classifier.configuration_classifier import RewardClassifierConfig as RewardClassifierConfig
+from .factory import (
+    get_reward_model_class as get_reward_model_class,
+    make_reward_model as make_reward_model,
+    make_reward_model_config as make_reward_model_config,
+    make_reward_pre_post_processors as make_reward_pre_post_processors,
+)
+from .pretrained import PreTrainedRewardModel as PreTrainedRewardModel
+from .sarm.configuration_sarm import SARMConfig as SARMConfig
+
+__all__ = [
+    # Configuration classes
+    "RewardClassifierConfig",
+    "SARMConfig",
+    # Base class
+    "PreTrainedRewardModel",
+    # Factory functions
+    "get_reward_model_class",
+    "make_reward_model",
+    "make_reward_model_config",
+    "make_reward_pre_post_processors",
+]

src/lerobot/rewards/classifier/configuration_classifier.py

@@ -1,5 +1,3 @@
-# !/usr/bin/env python
-
 # Copyright 2025 The HuggingFace Inc. team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -15,14 +13,15 @@
 # limitations under the License.
 from dataclasses import dataclass, field
 
-from lerobot.configs import NormalizationMode, PreTrainedConfig
+from lerobot.configs import NormalizationMode
+from lerobot.configs.rewards import RewardModelConfig
 from lerobot.optim import AdamWConfig, LRSchedulerConfig, OptimizerConfig
 from lerobot.utils.constants import OBS_IMAGE
 
 
-@PreTrainedConfig.register_subclass(name="reward_classifier")
+@RewardModelConfig.register_subclass(name="reward_classifier")
 @dataclass
-class RewardClassifierConfig(PreTrainedConfig):
+class RewardClassifierConfig(RewardModelConfig):
     """Configuration for the Reward Classifier model."""
 
     name: str = "reward_classifier"

src/lerobot/rewards/classifier/modeling_classifier.py

@@ -1,5 +1,3 @@
-# !/usr/bin/env python
-
 # Copyright 2025 The HuggingFace Inc. team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -19,11 +17,10 @@ import logging
 import torch
 from torch import Tensor, nn
 
+from lerobot.rewards.classifier.configuration_classifier import RewardClassifierConfig
+from lerobot.rewards.pretrained import PreTrainedRewardModel
 from lerobot.utils.constants import OBS_IMAGE, REWARD
 
-from ...pretrained import PreTrainedPolicy
-from .configuration_classifier import RewardClassifierConfig
-
 
 class ClassifierOutput:
     """Wrapper for classifier outputs with additional metadata."""
@@ -99,7 +96,7 @@ class SpatialLearnedEmbeddings(nn.Module):
         return output
 
 
-class Classifier(PreTrainedPolicy):
+class Classifier(PreTrainedRewardModel):
     """Image classifier built on top of a pre-trained encoder."""
 
     name = "reward_classifier"
@@ -235,6 +232,16 @@ class Classifier(PreTrainedPolicy):
 
         return ClassifierOutput(logits=logits, probabilities=probabilities, hidden_states=encoder_outputs)
 
+    def compute_reward(self, batch: dict[str, Tensor]) -> Tensor:
+        """Returns 1.0 for success, 0.0 for failure based on image observations."""
+        images = [batch[key] for key in self.config.input_features if key.startswith(OBS_IMAGE)]
+        output = self.predict(images)
+
+        if self.config.num_classes == 2:
+            return (output.probabilities > 0.5).float()
+        else:
+            return torch.argmax(output.probabilities, dim=1).float()
+
     def forward(self, batch: dict[str, Tensor]) -> tuple[Tensor, dict[str, Tensor]]:
         """Standard forward pass for training compatible with train.py."""
         # Extract images and labels
@@ -269,10 +276,6 @@ class Classifier(PreTrainedPolicy):
 
     def predict_reward(self, batch, threshold=0.5):
         """Eval method. Returns predicted reward with the decision threshold as argument."""
-        # Check for both OBS_IMAGE and OBS_IMAGES prefixes
-        batch = self.normalize_inputs(batch)
-        batch = self.normalize_targets(batch)
-
         # Extract images from batch dict
         images = [batch[key] for key in self.config.input_features if key.startswith(OBS_IMAGE)]
 
@@ -282,28 +285,3 @@ class Classifier(PreTrainedPolicy):
             return (probs > threshold).float()
         else:
             return torch.argmax(self.predict(images).probabilities, dim=1)
-
-    def get_optim_params(self):
-        """Return optimizer parameters for the policy."""
-        return self.parameters()
-
-    def select_action(self, batch: dict[str, Tensor]) -> Tensor:
-        """
-        This method is required by PreTrainedPolicy but not used for reward classifiers.
-        The reward classifier is not an actor and does not select actions.
-        """
-        raise NotImplementedError("Reward classifiers do not select actions")
-
-    def predict_action_chunk(self, batch: dict[str, Tensor]) -> Tensor:
-        """
-        This method is required by PreTrainedPolicy but not used for reward classifiers.
-        The reward classifier is not an actor and does not produce action chunks.
-        """
-        raise NotImplementedError("Reward classifiers do not predict action chunks")
-
-    def reset(self):
-        """
-        This method is required by PreTrainedPolicy but not used for reward classifiers.
-        The reward classifier is not an actor and does not select actions.
-        """
-        pass

src/lerobot/rewards/classifier/processor_classifier.py

@@ -1,5 +1,3 @@
-# !/usr/bin/env python
-
 # Copyright 2025 The HuggingFace Inc. team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -27,8 +25,7 @@ from lerobot.processor import (
     policy_action_to_transition,
     transition_to_policy_action,
 )
-
-from .configuration_classifier import RewardClassifierConfig
+from lerobot.rewards.classifier.configuration_classifier import RewardClassifierConfig
 
 
 def make_classifier_processor(
@@ -52,8 +49,6 @@ def make_classifier_processor(
     Args:
         config: The configuration object for the RewardClassifier.
         dataset_stats: A dictionary of statistics for normalization.
-        preprocessor_kwargs: Additional arguments for the pre-processor pipeline.
-        postprocessor_kwargs: Additional arguments for the post-processor pipeline.
 
     Returns:
         A tuple containing the configured pre-processor and post-processor pipelines.

src/lerobot/rewards/factory.py

@@ -0,0 +1,238 @@
+#!/usr/bin/env python
+
+# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import importlib
+import logging
+from typing import Any
+
+import torch
+
+from lerobot.configs.rewards import RewardModelConfig
+from lerobot.processor import PolicyAction, PolicyProcessorPipeline
+from lerobot.rewards.classifier.configuration_classifier import RewardClassifierConfig
+from lerobot.rewards.pretrained import PreTrainedRewardModel
+from lerobot.rewards.sarm.configuration_sarm import SARMConfig
+
+
+def get_reward_model_class(name: str) -> type[PreTrainedRewardModel]:
+    """
+    Retrieves a reward model class by its registered name.
+
+    This function uses dynamic imports to avoid loading all reward model classes into
+    memory at once, improving startup time and reducing dependencies.
+
+    Args:
+        name: The name of the reward model. Supported names are "reward_classifier",
+              "sarm".
+
+    Returns:
+        The reward model class corresponding to the given name.
+
+    Raises:
+        ValueError: If the reward model name is not recognized.
+    """
+    if name == "reward_classifier":
+        from lerobot.rewards.classifier.modeling_classifier import Classifier
+
+        return Classifier
+    elif name == "sarm":
+        from lerobot.rewards.sarm.modeling_sarm import SARMRewardModel
+
+        return SARMRewardModel
+    else:
+        try:
+            return _get_reward_model_cls_from_name(name=name)
+        except Exception as e:
+            raise ValueError(f"Reward model type '{name}' is not available.") from e
+
+
+def make_reward_model_config(reward_type: str, **kwargs) -> RewardModelConfig:
+    """
+    Instantiates a reward model configuration object based on the reward type.
+
+    This factory function simplifies the creation of reward model configuration objects
+    by mapping a string identifier to the corresponding config class.
+
+    Args:
+        reward_type: The type of the reward model. Supported types include
+                     "reward_classifier", "sarm".
+        **kwargs: Keyword arguments to be passed to the configuration class constructor.
+
+    Returns:
+        An instance of a `RewardModelConfig` subclass.
+
+    Raises:
+        ValueError: If the `reward_type` is not recognized.
+    """
+    if reward_type == "reward_classifier":
+        return RewardClassifierConfig(**kwargs)
+    elif reward_type == "sarm":
+        return SARMConfig(**kwargs)
+    else:
+        try:
+            config_cls = RewardModelConfig.get_choice_class(reward_type)
+            return config_cls(**kwargs)
+        except Exception as e:
+            raise ValueError(f"Reward model type '{reward_type}' is not available.") from e
+
+
+def make_reward_model(cfg: RewardModelConfig, **kwargs) -> PreTrainedRewardModel:
+    """
+    Instantiate a reward model from its configuration.
+
+    Args:
+        cfg: The configuration for the reward model to be created. If
+             `cfg.pretrained_path` is set, the model will be loaded with weights
+             from that path.
+        **kwargs: Additional keyword arguments forwarded to the model constructor
+            (e.g., ``dataset_stats``, ``dataset_meta``).
+
+    Returns:
+        An instantiated and device-placed reward model.
+    """
+    reward_cls = get_reward_model_class(cfg.type)
+
+    kwargs["config"] = cfg
+
+    if cfg.pretrained_path:
+        kwargs["pretrained_name_or_path"] = cfg.pretrained_path
+        reward_model = reward_cls.from_pretrained(**kwargs)
+    else:
+        reward_model = reward_cls(**kwargs)
+
+    reward_model.to(cfg.device)
+    assert isinstance(reward_model, torch.nn.Module)
+
+    return reward_model
+
+
+def make_reward_pre_post_processors(
+    reward_cfg: RewardModelConfig,
+    **kwargs,
+) -> tuple[
+    PolicyProcessorPipeline[dict[str, Any], dict[str, Any]],
+    PolicyProcessorPipeline[PolicyAction, PolicyAction],
+]:
+    """
+    Create pre- and post-processor pipelines for a given reward model.
+
+    Each reward model type has a dedicated factory function for its processors.
+
+    Args:
+        reward_cfg: The configuration of the reward model for which to create processors.
+        **kwargs: Additional keyword arguments passed to the processor factory
+            (e.g., ``dataset_stats``, ``dataset_meta``).
+
+    Returns:
+        A tuple containing the input (pre-processor) and output (post-processor) pipelines.
+
+    Raises:
+        ValueError: If a processor factory is not implemented for the given reward
+            model configuration type.
+    """
+    # Create a new processor based on reward model type
+    if isinstance(reward_cfg, RewardClassifierConfig):
+        from lerobot.rewards.classifier.processor_classifier import make_classifier_processor
+
+        return make_classifier_processor(
+            config=reward_cfg,
+            dataset_stats=kwargs.get("dataset_stats"),
+        )
+
+    elif isinstance(reward_cfg, SARMConfig):
+        from lerobot.rewards.sarm.processor_sarm import make_sarm_pre_post_processors
+
+        return make_sarm_pre_post_processors(
+            config=reward_cfg,
+            dataset_stats=kwargs.get("dataset_stats"),
+            dataset_meta=kwargs.get("dataset_meta"),
+        )
+
+    else:
+        try:
+            processors = _make_processors_from_reward_model_config(
+                config=reward_cfg,
+                dataset_stats=kwargs.get("dataset_stats"),
+            )
+        except Exception as e:
+            raise ValueError(
+                f"Processor for reward model type '{reward_cfg.type}' is not implemented."
+            ) from e
+        return processors
+
+
+def _get_reward_model_cls_from_name(name: str) -> type[PreTrainedRewardModel]:
+    """Get reward model class from its registered name using dynamic imports.
+
+    This is used as a helper function to import reward models from 3rd party lerobot
+    plugins.
+
+    Args:
+        name: The name of the reward model.
+
+    Returns:
+        The reward model class corresponding to the given name.
+    """
+    if name not in RewardModelConfig.get_known_choices():
+        raise ValueError(
+            f"Unknown reward model name '{name}'. "
+            f"Available reward models: {RewardModelConfig.get_known_choices()}"
+        )
+
+    config_cls = RewardModelConfig.get_choice_class(name)
+    config_cls_name = config_cls.__name__
+
+    model_name = config_cls_name.removesuffix("Config")
+    if model_name == config_cls_name:
+        raise ValueError(
+            f"The config class name '{config_cls_name}' does not follow the expected naming convention. "
+            f"Make sure it ends with 'Config'!"
+        )
+
+    cls_name = model_name + "RewardModel"
+    module_path = config_cls.__module__.replace("configuration_", "modeling_")
+
+    module = importlib.import_module(module_path)
+    reward_cls = getattr(module, cls_name)
+    return reward_cls
+
+
+def _make_processors_from_reward_model_config(
+    config: RewardModelConfig,
+    dataset_stats: dict[str, dict[str, torch.Tensor]] | None = None,
+) -> tuple[Any, Any]:
+    """Create pre- and post-processors from a reward model configuration using dynamic imports.
+
+    This is used as a helper function to import processor factories from 3rd party
+    lerobot reward model plugins.
+
+    Args:
+        config: The reward model configuration object.
+        dataset_stats: Dataset statistics for normalization.
+
+    Returns:
+        A tuple containing the input (pre-processor) and output (post-processor) pipelines.
+    """
+    reward_type = config.type
+    function_name = f"make_{reward_type}_pre_post_processors"
+    module_path = config.__class__.__module__.replace("configuration_", "processor_")
+    logging.debug(
+        f"Instantiating reward pre/post processors using function '{function_name}' "
+        f"from module '{module_path}'"
+    )
+    module = importlib.import_module(module_path)
+    function = getattr(module, function_name)
+    return function(config, dataset_stats=dataset_stats)

src/lerobot/rewards/pretrained.py

@@ -0,0 +1,244 @@
+# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import abc
+import builtins
+import logging
+import os
+from importlib.resources import files
+from pathlib import Path
+from tempfile import TemporaryDirectory
+from typing import TYPE_CHECKING, Any, TypeVar
+
+import packaging
+import safetensors
+from huggingface_hub import HfApi, ModelCard, ModelCardData, hf_hub_download
+from huggingface_hub.constants import SAFETENSORS_SINGLE_FILE
+from huggingface_hub.errors import HfHubHTTPError
+from safetensors.torch import load_model as load_model_as_safetensor, save_model as save_model_as_safetensor
+from torch import Tensor, nn
+
+from lerobot.configs.rewards import RewardModelConfig
+from lerobot.utils.hub import HubMixin
+
+if TYPE_CHECKING:
+    from lerobot.configs.train import TrainPipelineConfig
+
+T = TypeVar("T", bound="PreTrainedRewardModel")
+
+
+class PreTrainedRewardModel(nn.Module, HubMixin, abc.ABC):
+    """Base class for reward models."""
+
+    config_class: None
+    name: None
+
+    def __init__(self, config: RewardModelConfig, *inputs, **kwargs):
+        super().__init__()
+        if not isinstance(config, RewardModelConfig):
+            raise ValueError(
+                f"Parameter config in `{self.__class__.__name__}(config)` should be an instance of class "
+                "`RewardModelConfig`. To create a model from a pretrained model use "
+                f"`model = {self.__class__.__name__}.from_pretrained(PRETRAINED_MODEL_NAME)`"
+            )
+        self.config = config
+
+    def __init_subclass__(cls, **kwargs):
+        super().__init_subclass__(**kwargs)
+        if not getattr(cls, "config_class", None):
+            raise TypeError(f"Class {cls.__name__} must define 'config_class'")
+        if not getattr(cls, "name", None):
+            raise TypeError(f"Class {cls.__name__} must define 'name'")
+
+    def _save_pretrained(self, save_directory: Path) -> None:
+        self.config._save_pretrained(save_directory)
+        model_to_save = self.module if hasattr(self, "module") else self
+        save_model_as_safetensor(model_to_save, str(save_directory / SAFETENSORS_SINGLE_FILE))
+
+    @classmethod
+    def from_pretrained(
+        cls: builtins.type[T],
+        pretrained_name_or_path: str | Path,
+        *,
+        config: RewardModelConfig | None = None,
+        force_download: bool = False,
+        resume_download: bool | None = None,
+        proxies: dict | None = None,
+        token: str | bool | None = None,
+        cache_dir: str | Path | None = None,
+        local_files_only: bool = False,
+        revision: str | None = None,
+        strict: bool = False,
+        **kwargs,
+    ) -> T:
+        """
+        The reward model is set in evaluation mode by default using `reward.eval()` (dropout modules are
+        deactivated). To train it, you should first set it back in training mode with `reward.train()`.
+        """
+        if config is None:
+            config = RewardModelConfig.from_pretrained(
+                pretrained_name_or_path=pretrained_name_or_path,
+                force_download=force_download,
+                resume_download=resume_download,
+                proxies=proxies,
+                token=token,
+                cache_dir=cache_dir,
+                local_files_only=local_files_only,
+                revision=revision,
+                **kwargs,
+            )
+        model_id = str(pretrained_name_or_path)
+        instance = cls(config, **kwargs)
+        if os.path.isdir(model_id):
+            print("Loading weights from local directory")
+            model_file = os.path.join(model_id, SAFETENSORS_SINGLE_FILE)
+            reward = cls._load_as_safetensor(instance, model_file, config.device or "cpu", strict)
+        else:
+            try:
+                model_file = hf_hub_download(
+                    repo_id=model_id,
+                    filename=SAFETENSORS_SINGLE_FILE,
+                    revision=revision,
+                    cache_dir=cache_dir,
+                    force_download=force_download,
+                    proxies=proxies,
+                    resume_download=resume_download,
+                    token=token,
+                    local_files_only=local_files_only,
+                )
+                reward = cls._load_as_safetensor(instance, model_file, config.device or "cpu", strict)
+            except HfHubHTTPError as e:
+                raise FileNotFoundError(
+                    f"{SAFETENSORS_SINGLE_FILE} not found on the HuggingFace Hub in {model_id}"
+                ) from e
+
+        reward.to(config.device)
+        reward.eval()
+        return reward
+
+    @classmethod
+    def _load_as_safetensor(cls, model: T, model_file: str, map_location: str, strict: bool) -> T:
+        # Create base kwargs
+        kwargs = {"strict": strict}
+
+        # Add device parameter for newer versions that support it
+        if packaging.version.parse(safetensors.__version__) >= packaging.version.parse("0.4.3"):
+            kwargs["device"] = map_location
+
+        # Load the model with appropriate kwargs
+        missing_keys, unexpected_keys = load_model_as_safetensor(model, model_file, **kwargs)
+        if missing_keys:
+            logging.warning(f"Missing key(s) when loading model: {missing_keys}")
+        if unexpected_keys:
+            logging.warning(f"Unexpected key(s) when loading model: {unexpected_keys}")
+
+        # For older versions, manually move to device if needed
+        if "device" not in kwargs and map_location != "cpu":
+            logging.warning(
+                "Loading model weights on other devices than 'cpu' is not supported natively in your version of safetensors."
+                " This means that the model is loaded on 'cpu' first and then copied to the device."
+                " This leads to a slower loading time."
+                " Please update safetensors to version 0.4.3 or above for improved performance."
+            )
+            model.to(map_location)
+        return model
+
+    def get_optim_params(self):
+        """
+        Returns the reward-model-specific parameters dict to be passed on to the optimizer.
+        """
+        return self.parameters()
+
+    def reset(self) -> None:
+        """Reset any internal state."""
+        pass
+
+    @abc.abstractmethod
+    def compute_reward(self, batch: dict[str, Tensor]) -> Tensor:
+        """Compute a scalar reward signal for a batch of observations.
+
+        Args:
+            batch: Dictionary containing at minimum observation tensors.
+                   May also contain "action", "next_observation.*", etc.
+
+        Returns:
+            Tensor of shape ``(batch_size,)`` with reward values.
+        """
+        ...
+
+    def forward(self, batch: dict[str, Tensor]) -> tuple[Tensor, dict[str, Any]]:
+        """Training forward pass — override for trainable reward models."""
+        raise NotImplementedError(
+            f"{self.__class__.__name__} is not trainable. Only use compute_reward() for inference."
+        )
+
+    @property
+    def is_trainable(self) -> bool:
+        """Whether this reward model can be trained via ``lerobot-train``.
+
+        Trainable reward models override :meth:`forward`; zero-shot models
+        inherit the base implementation that raises ``NotImplementedError``.
+        """
+        return type(self).forward is not PreTrainedRewardModel.forward
+
+    def push_model_to_hub(self, cfg: "TrainPipelineConfig"):
+        api = HfApi()
+        repo_id = api.create_repo(
+            repo_id=self.config.repo_id, private=self.config.private, exist_ok=True
+        ).repo_id
+
+        # Push the files to the repo in a single commit
+        with TemporaryDirectory(ignore_cleanup_errors=True) as tmp:
+            saved_path = Path(tmp) / repo_id
+
+            self.save_pretrained(saved_path)  # Calls _save_pretrained and stores model tensors
+
+            card = self.generate_model_card(
+                cfg.dataset.repo_id, self.config.type, self.config.license, self.config.tags
+            )
+            card.save(str(saved_path / "README.md"))
+
+            cfg.save_pretrained(saved_path)  # Calls _save_pretrained and stores train config
+
+            commit_info = api.upload_folder(
+                repo_id=repo_id,
+                repo_type="model",
+                folder_path=saved_path,
+                commit_message="Upload reward model weights, train config and readme",
+                allow_patterns=["*.safetensors", "*.json", "*.yaml", "*.md"],
+                ignore_patterns=["*.tmp", "*.log"],
+            )
+
+            logging.info(f"Model pushed to {commit_info.repo_url.url}")
+
+    def generate_model_card(
+        self, dataset_repo_id: str, model_type: str, license: str | None, tags: list[str] | None
+    ) -> ModelCard:
+        card_data = ModelCardData(
+            license=license or "apache-2.0",
+            library_name="lerobot",
+            pipeline_tag="robotics",
+            tags=list(set(tags or []).union({"robotics", "lerobot", "reward-model", model_type})),
+            model_name=model_type,
+            datasets=dataset_repo_id,
+        )
+
+        template_card = (
+            files("lerobot.templates")
+            .joinpath("lerobot_rewardmodel_modelcard_template.md")
+            .read_text(encoding="utf-8")
+        )
+        card = ModelCard.from_template(card_data, template_str=template_card)
+        card.validate()
+        return card

src/lerobot/rewards/sarm/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2024 The HuggingFace Inc. team. All rights reserved.
+# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -14,5 +14,6 @@
 
 from .configuration_sarm import SARMConfig
 from .modeling_sarm import SARMRewardModel
+from .processor_sarm import make_sarm_pre_post_processors
 
-__all__ = ["SARMConfig", "SARMRewardModel"]
+__all__ = ["SARMConfig", "SARMRewardModel", "make_sarm_pre_post_processors"]

src/lerobot/rewards/sarm/compute_rabc_weights.py

@@ -25,18 +25,18 @@ need ~num_frames/30 queries instead of one per frame (~30x speedup).
 
 Usage:
     # Full RA-BC computation with visualizations
-    python src/lerobot/policies/sarm/compute_rabc_weights.py \\
+    python src/lerobot/rewards/sarm/compute_rabc_weights.py \\
         --dataset-repo-id lerobot/aloha_sim_insertion_human \\
         --reward-model-path <USER>/sarm_single_uni4
 
     # Faster computation with stride (compute every 5 frames, interpolate the rest)
-    python src/lerobot/policies/sarm/compute_rabc_weights.py \\
+    python src/lerobot/rewards/sarm/compute_rabc_weights.py \\
         --dataset-repo-id lerobot/aloha_sim_insertion_human \\
         --reward-model-path <USER>/sarm_single_uni4 \\
         --stride 5
 
     # Visualize predictions only (no RA-BC computation)
-    python src/lerobot/policies/sarm/compute_rabc_weights.py \\
+    python src/lerobot/rewards/sarm/compute_rabc_weights.py \\
         --dataset-repo-id lerobot/aloha_sim_insertion_human \\
         --reward-model-path <USER>/sarm_single_uni4 \\
         --visualize-only \\
@@ -58,10 +58,9 @@ import torch
 from tqdm import tqdm
 
 from lerobot.datasets import LeRobotDataset
-
-from .modeling_sarm import SARMRewardModel
-from .processor_sarm import make_sarm_pre_post_processors
-from .sarm_utils import normalize_stage_tau
+from lerobot.rewards.sarm.modeling_sarm import SARMRewardModel
+from lerobot.rewards.sarm.processor_sarm import make_sarm_pre_post_processors
+from lerobot.rewards.sarm.sarm_utils import normalize_stage_tau
 
 
 def get_reward_model_path_from_parquet(parquet_path: Path) -> str | None:
@@ -713,12 +712,12 @@ def main():
         epilog="""
 Examples:
     # Full RA-BC computation with visualizations
-    python src/lerobot/policies/sarm/compute_rabc_weights.py \\
+    python src/lerobot/rewards/sarm/compute_rabc_weights.py \\
         --dataset-repo-id lerobot/aloha_sim_insertion_human \\
         --reward-model-path <USER>/sarm_single_uni4
 
     # Visualize predictions only (no RA-BC computation)
-    python src/lerobot/policies/sarm/compute_rabc_weights.py \\
+    python src/lerobot/rewards/sarm/compute_rabc_weights.py \\
         --dataset-repo-id lerobot/aloha_sim_insertion_human \\
         --reward-model-path <USER>/sarm_single_uni4 \\
         --visualize-only \\

src/lerobot/rewards/sarm/configuration_sarm.py

@@ -1,5 +1,3 @@
-#!/usr/bin/env python
-
 # Copyright 2025 Qianzhong Chen, Justin Yu, Mac Schwager, Pieter Abbeel, Yide Shentu, Philipp Wu
 # and The HuggingFace Inc. team. All rights reserved.
 #
@@ -22,14 +20,15 @@ Paper: https://arxiv.org/abs/2509.25358
 
 from dataclasses import dataclass, field
 
-from lerobot.configs import FeatureType, NormalizationMode, PolicyFeature, PreTrainedConfig
+from lerobot.configs import FeatureType, NormalizationMode, PolicyFeature
+from lerobot.configs.rewards import RewardModelConfig
 from lerobot.optim import AdamWConfig, CosineDecayWithWarmupSchedulerConfig
 from lerobot.utils.constants import OBS_IMAGES, OBS_STATE
 
 
-@PreTrainedConfig.register_subclass("sarm")
+@RewardModelConfig.register_subclass("sarm")
 @dataclass
-class SARMConfig(PreTrainedConfig):
+class SARMConfig(RewardModelConfig):
     """Configuration class for SARM (Stage-Aware Reward Modeling).
 
     Supports three annotation modes:
@@ -110,7 +109,6 @@ class SARMConfig(PreTrainedConfig):
 
     def __post_init__(self):
         super().__post_init__()
-
         if self.annotation_mode not in ["single_stage", "dense_only", "dual"]:
             raise ValueError(
                 f"annotation_mode must be 'single_stage', 'dense_only', or 'dual', got {self.annotation_mode}"

src/lerobot/rewards/sarm/modeling_sarm.py

@@ -1,5 +1,3 @@
-#!/usr/bin/env python
-
 # Copyright 2025 Qianzhong Chen, Justin Yu, Mac Schwager, Pieter Abbeel, Yide Shentu, Philipp Wu
 # and The HuggingFace Inc. team. All rights reserved.
 #
@@ -34,14 +32,13 @@ import torch.nn as nn
 import torch.nn.functional as F  # noqa: N812
 from torch import Tensor
 
-from lerobot.utils.constants import OBS_STR
-
-from ..pretrained import PreTrainedPolicy
-from .configuration_sarm import SARMConfig
-from .sarm_utils import (
+from lerobot.rewards.pretrained import PreTrainedRewardModel
+from lerobot.rewards.sarm.configuration_sarm import SARMConfig
+from lerobot.rewards.sarm.sarm_utils import (
     normalize_stage_tau,
     pad_state_to_max_dim,
 )
+from lerobot.utils.constants import OBS_STR
 
 
 class StageTransformer(nn.Module):
@@ -353,7 +350,7 @@ def gen_stage_emb(num_classes: int, targets: torch.Tensor) -> torch.Tensor:
     return stage_onehot
 
 
-class SARMRewardModel(PreTrainedPolicy):
+class SARMRewardModel(PreTrainedRewardModel):
     """
     SARM Reward Model for stage-aware task completion rewards.
 
@@ -471,6 +468,23 @@ class SARMRewardModel(PreTrainedPolicy):
         self.subtask_model.to(device)
         return self
 
+    def compute_reward(self, batch: dict[str, Tensor]) -> Tensor:
+        """Compute dense progress reward in [0, 1] from batch.
+
+        Expects batch to contain:
+        - "observation_features" or video embeddings: (B, T, 512)
+        - "language_embedding" or text embeddings: (B, 512)
+        - optionally "observation.state": (B, T, state_dim)
+        """
+        text_emb = batch.get("language_embedding", batch.get("text_features"))
+        video_emb = batch.get("observation_features", batch.get("video_features"))
+        state = batch.get("observation.state", batch.get("state_features"))
+
+        rewards = self.calculate_rewards(text_emb, video_emb, state)
+        if isinstance(rewards, np.ndarray):
+            rewards = torch.from_numpy(rewards).float()
+        return rewards
+
     @torch.no_grad()
     def calculate_rewards(
         self,
@@ -631,17 +645,9 @@ class SARMRewardModel(PreTrainedPolicy):
         return self.parameters()
 
     def reset(self):
-        """Required by PreTrainedPolicy but not used for reward models."""
+        """SARM has no episode-level state to reset."""
         pass
 
-    def predict_action_chunk(self, batch: dict[str, Tensor]) -> Tensor:
-        """Required by PreTrainedPolicy but not used for reward models."""
-        raise NotImplementedError("SARM model does not predict action chunks")
-
-    def select_action(self, batch: dict[str, Tensor]) -> Tensor:
-        """Required by PreTrainedPolicy but not used for SARM."""
-        raise NotImplementedError("SARM model does not select actions")
-
     def _train_step(
         self,
         img_emb: torch.Tensor,  # (B, N, T, D)

src/lerobot/rewards/sarm/processor_sarm.py

@@ -1,5 +1,3 @@
-#!/usr/bin/env python
-
 # Copyright 2025 The HuggingFace Inc. team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -60,16 +58,15 @@ from lerobot.processor import (
     policy_action_to_transition,
     transition_to_policy_action,
 )
-from lerobot.types import EnvTransition, PolicyAction, TransitionKey
-from lerobot.utils.constants import POLICY_POSTPROCESSOR_DEFAULT_NAME, POLICY_PREPROCESSOR_DEFAULT_NAME
-
-from .configuration_sarm import SARMConfig
-from .sarm_utils import (
+from lerobot.rewards.sarm.configuration_sarm import SARMConfig
+from lerobot.rewards.sarm.sarm_utils import (
     apply_rewind_augmentation,
     compute_absolute_indices,
     find_stage_and_tau,
     pad_state_to_max_dim,
 )
+from lerobot.types import EnvTransition, PolicyAction, TransitionKey
+from lerobot.utils.constants import POLICY_POSTPROCESSOR_DEFAULT_NAME, POLICY_PREPROCESSOR_DEFAULT_NAME
 
 
 class SARMEncodingProcessorStep(ProcessorStep):
@@ -455,7 +452,13 @@ class SARMEncodingProcessorStep(ProcessorStep):
             inputs = {k: v.to(self.device) for k, v in inputs.items()}
 
             # Get image embeddings
-            embeddings = self.clip_model.get_image_features(**inputs).detach().cpu()
+            # transformers 5.x returns BaseModelOutputWithPooling instead of a plain tensor
+            output = self.clip_model.get_image_features(**inputs)
+            if not isinstance(output, torch.Tensor):
+                output = output.pooler_output
+                if output is None:
+                    raise ValueError("pooler_output should not be None for CLIP models.")
+            embeddings = output.detach().cpu()
 
             # Handle single frame case
             if embeddings.dim() == 1:
@@ -482,7 +485,13 @@ class SARMEncodingProcessorStep(ProcessorStep):
         inputs = self.clip_processor.tokenizer([text], return_tensors="pt", padding=True, truncation=True)
         inputs = {k: v.to(self.device) for k, v in inputs.items()}
 
-        text_embedding = self.clip_model.get_text_features(**inputs).detach().cpu()
+        # transformers 5.x returns BaseModelOutputWithPooling instead of a plain tensor
+        output = self.clip_model.get_text_features(**inputs)
+        if not isinstance(output, torch.Tensor):
+            output = output.pooler_output
+            if output is None:
+                raise ValueError("pooler_output should not be None for CLIP models.")
+        text_embedding = output.detach().cpu()
         text_embedding = text_embedding.expand(batch_size, -1)
 
         return text_embedding

src/lerobot/rewards/sarm/rabc.py

@@ -1,5 +1,3 @@
-#!/usr/bin/env python
-
 # Copyright 2025 The HuggingFace Inc. team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -14,14 +12,38 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+"""
+RA-BC (Reward-Aligned Behavior Cloning) sample weighting implementation.
+
+This module implements the SampleWeighter protocol for RA-BC training,
+which weights training samples based on their task progress as measured
+by the SARM reward model.
+
+The weights are computed based on progress deltas:
+    delta = progress[t + chunk_size] - progress[t]
+
+High-quality samples (positive progress) get higher weights, while
+samples with negative progress (going backwards) get zero weight.
+
+See: https://arxiv.org/abs/2509.25358 for the SARM paper.
+"""
+
 import logging
 from pathlib import Path
+from typing import TYPE_CHECKING
 
 import numpy as np
-import pandas as pd
 import torch
 from huggingface_hub import hf_hub_download
 
+from lerobot.utils.import_utils import _pandas_available
+from lerobot.utils.sample_weighting import SampleWeighter
+
+if TYPE_CHECKING or _pandas_available:
+    import pandas as pd
+else:
+    pd = None  # type: ignore[assignment]
+
 
 def resolve_hf_path(path: str | Path) -> Path:
     """Resolve a path that may be a HuggingFace URL (hf://datasets/...) to a local path."""
@@ -34,23 +56,27 @@ def resolve_hf_path(path: str | Path) -> Path:
     return Path(path)
 
 
-class RABCWeights:
+class RABCWeights(SampleWeighter):
     """
     Load precomputed SARM progress values and compute RA-BC weights during training.
 
+    This class implements the SampleWeighter ABC for use with the generic
+    sample weighting infrastructure in lerobot.
+
     Progress values are loaded from a parquet file (generated by compute_rabc_weights.py).
     During training, computes:
         - progress_delta = progress[t + chunk_size] - progress[t]
         - rabc_weight based on the delta (paper Eq. 8-9)
 
     Args:
-        progress_path: Path to parquet file with precomputed progress values
-        chunk_size: Number of frames ahead for computing progress delta
-        head_mode: Which SARM head to use ("sparse" or "dense")
-        kappa: Hard threshold for high-quality samples (default: 0.01)
-        epsilon: Small constant for numerical stability (default: 1e-6)
-        fallback_weight: Weight to use for frames without valid delta (default: 1.0)
-        device: Device to return tensors on
+        progress_path: Path to parquet file with precomputed progress values.
+                      Supports HuggingFace URLs (hf://datasets/...).
+        chunk_size: Number of frames ahead for computing progress delta.
+        head_mode: Which SARM head to use ("sparse" or "dense").
+        kappa: Hard threshold for high-quality samples (default: 0.01).
+        epsilon: Small constant for numerical stability (default: 1e-6).
+        fallback_weight: Weight to use for frames without valid delta (default: 1.0).
+        device: Device to return tensors on.
     """
 
     def __init__(
@@ -61,7 +87,7 @@ class RABCWeights:
         kappa: float = 0.01,
         epsilon: float = 1e-6,
         fallback_weight: float = 1.0,
-        device: torch.device = None,
+        device: torch.device | None = None,
     ):
         self.progress_path = resolve_hf_path(progress_path)
         self.chunk_size = chunk_size
@@ -87,8 +113,8 @@ class RABCWeights:
 
         logging.info(f"Using progress column: {self.progress_column}")
 
-        self.progress_lookup = {}
-        self.episode_lookup = {}
+        self.progress_lookup: dict[int, float] = {}
+        self.episode_lookup: dict[int, int] = {}
 
         for _, row in self.df.iterrows():
             global_idx = int(row["index"])
@@ -100,7 +126,7 @@ class RABCWeights:
             self.episode_lookup[global_idx] = episode_idx
 
         # Build episode boundaries for delta computation
-        self.episode_boundaries = {}
+        self.episode_boundaries: dict[int, dict[str, int]] = {}
         for episode_idx in self.df["episode_index"].unique():
             ep_df = self.df[self.df["episode_index"] == episode_idx]
             self.episode_boundaries[int(episode_idx)] = {
@@ -114,7 +140,7 @@ class RABCWeights:
         # Compute global statistics for weight computation
         self._compute_global_stats()
 
-    def _compute_global_stats(self):
+    def _compute_global_stats(self) -> None:
         """Compute global mean and std of progress deltas for weight calculation."""
         all_deltas = []
 
@@ -138,8 +164,8 @@ class RABCWeights:
                 all_deltas.append(delta)
 
         if all_deltas:
-            self.delta_mean = max(np.mean(all_deltas), 0.0)
-            self.delta_std = max(np.std(all_deltas), self.epsilon)
+            self.delta_mean = max(float(np.mean(all_deltas)), 0.0)
+            self.delta_std = max(float(np.std(all_deltas)), self.epsilon)
             logging.info(f"Progress delta stats: mean={self.delta_mean:.4f}, std={self.delta_std:.4f}")
         else:
             self.delta_mean = 0.0
@@ -157,18 +183,19 @@ class RABCWeights:
         4. Compute weight using paper Eq. 8-9
 
         Args:
-            batch: Training batch containing "index" key with global frame indices
+            batch: Training batch containing "index" key with global frame indices.
 
         Returns:
             Tuple of:
-            - Weights tensor (batch_size,) normalized to sum to batch_size
-            - Stats dict with raw_mean_weight, num_zero_weight, num_full_weight
+            - Weights tensor (batch_size,) normalized to sum to batch_size.
+            - Stats dict with weighting statistics for logging.
         """
         indices = batch.get("index")
         if indices is None:
             logging.warning("RA-BC: Batch missing 'index' key, using uniform weights")
             batch_size = self._get_batch_size(batch)
-            return torch.ones(batch_size, device=self.device), {"raw_mean_weight": 1.0}
+            stats = {"mean_weight": 1.0, "num_zero_weight": 0, "num_full_weight": batch_size}
+            return torch.ones(batch_size, device=self.device), stats
 
         # Convert to list of ints
         if isinstance(indices, torch.Tensor):
@@ -183,29 +210,29 @@ class RABCWeights:
             delta = self._compute_delta(idx)
             deltas.append(delta)
 
-        deltas = np.array(deltas, dtype=np.float32)
+        deltas_array = np.array(deltas, dtype=np.float32)
 
         # Compute weights from deltas
-        weights = self._compute_weights(deltas)
+        weights = self._compute_weights(deltas_array)
 
         # Compute stats before normalization for logging
         raw_mean_weight = float(np.nanmean(weights))
         num_zero_weight = int(np.sum(weights == 0))
         num_full_weight = int(np.sum(weights == 1.0))
         batch_stats = {
-            "raw_mean_weight": raw_mean_weight,
+            "mean_weight": raw_mean_weight,
             "num_zero_weight": num_zero_weight,
             "num_full_weight": num_full_weight,
         }
 
-        weights = torch.tensor(weights, device=self.device, dtype=torch.float32)
+        weights_tensor = torch.tensor(weights, device=self.device, dtype=torch.float32)
 
         # Normalize to sum to batch_size
-        batch_size = len(weights)
-        weight_sum = weights.sum() + self.epsilon
-        weights = weights * batch_size / weight_sum
+        batch_size = len(weights_tensor)
+        weight_sum = weights_tensor.sum() + self.epsilon
+        weights_tensor = weights_tensor * batch_size / weight_sum
 
-        return weights, batch_stats
+        return weights_tensor, batch_stats
 
     def _compute_delta(self, global_idx: int) -> float:
         """Compute progress delta for a single frame."""
@@ -241,7 +268,7 @@ class RABCWeights:
         - Final weight: wi = 1{ri > κ} + 1{0 ≤ ri ≤ κ}˜wi
 
         Returns:
-            Array of weights
+            Array of weights.
         """
         valid_mask = ~np.isnan(deltas)
 
@@ -273,12 +300,13 @@ class RABCWeights:
             if key in batch:
                 val = batch[key]
                 if isinstance(val, (torch.Tensor, np.ndarray)):
-                    return val.shape[0]
+                    return int(val.shape[0])
         return 1
 
     def get_stats(self) -> dict:
-        """Get statistics."""
+        """Get global statistics about the RA-BC weighting."""
         return {
+            "type": "rabc",
             "num_frames": len(self.progress_lookup),
             "chunk_size": self.chunk_size,
             "head_mode": self.head_mode,

src/lerobot/rewards/sarm/sarm_utils.py

@@ -1,5 +1,3 @@
-#!/usr/bin/env python
-
 # Copyright 2025 The HuggingFace Inc. team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

src/lerobot/rl/crop_dataset_roi.py

@@ -193,15 +193,15 @@ def convert_lerobot_dataset_to_cropped_lerobot_dataset(
         fps=int(original_dataset.fps),
         root=new_dataset_root,
         robot_type=original_dataset.meta.robot_type,
-        features=original_dataset.meta.info["features"],
+        features=original_dataset.meta.info.features,
         use_videos=len(original_dataset.meta.video_keys) > 0,
     )
 
     # Update the metadata for every image key that will be cropped:
     # (Here we simply set the shape to be the final resize_size.)
     for key in crop_params_dict:
-        if key in new_dataset.meta.info["features"]:
-            new_dataset.meta.info["features"][key]["shape"] = [3] + list(resize_size)
+        if key in new_dataset.meta.info.features:
+            new_dataset.meta.info.features[key]["shape"] = (3, *resize_size)
 
     # TODO:  Directly modify the mp4 video + meta info features, instead of recreating a dataset
     prev_episode_index = 0

src/lerobot/robots/bi_openarm_follower/bi_openarm_follower.py

@@ -54,6 +54,7 @@ class BiOpenArmFollower(Robot):
             calibration_dir=config.calibration_dir,
             port=config.left_arm_config.port,
             disable_torque_on_disconnect=config.left_arm_config.disable_torque_on_disconnect,
+            use_velocity_and_torque=config.left_arm_config.use_velocity_and_torque,
             max_relative_target=config.left_arm_config.max_relative_target,
             cameras=left_cameras,
             side=config.left_arm_config.side,
@@ -72,6 +73,7 @@ class BiOpenArmFollower(Robot):
             calibration_dir=config.calibration_dir,
             port=config.right_arm_config.port,
             disable_torque_on_disconnect=config.right_arm_config.disable_torque_on_disconnect,
+            use_velocity_and_torque=config.right_arm_config.use_velocity_and_torque,
             max_relative_target=config.right_arm_config.max_relative_target,
             cameras=right_cameras,
             side=config.right_arm_config.side,

src/lerobot/robots/openarm_follower/config_openarm_follower.py

@@ -66,6 +66,10 @@ class OpenArmFollowerConfigBase:
     # Whether to disable torque when disconnecting
     disable_torque_on_disconnect: bool = True
 
+    # When True, expose `.vel` and `.torque` per motor in observation features.
+    # Default False for compatibility with the position-only openarm_mini teleoperator.
+    use_velocity_and_torque: bool = False
+
     # Safety limit for relative target positions
     # Set to a positive scalar for all motors, or a dict mapping motor names to limits
     max_relative_target: float | dict[str, float] | None = None

src/lerobot/robots/openarm_follower/openarm_follower.py

@@ -93,8 +93,9 @@ class OpenArmFollower(Robot):
         features: dict[str, type] = {}
         for motor in self.bus.motors:
             features[f"{motor}.pos"] = float
-            features[f"{motor}.vel"] = float  # Add this
-            features[f"{motor}.torque"] = float  # Add this
+            if self.config.use_velocity_and_torque:
+                features[f"{motor}.vel"] = float
+                features[f"{motor}.torque"] = float
         return features
 
     @property
@@ -235,8 +236,9 @@ class OpenArmFollower(Robot):
         for motor in self.bus.motors:
             state = states.get(motor, {})
             obs_dict[f"{motor}.pos"] = state.get("position", 0.0)
-            obs_dict[f"{motor}.vel"] = state.get("velocity", 0.0)
-            obs_dict[f"{motor}.torque"] = state.get("torque", 0.0)
+            if self.config.use_velocity_and_torque:
+                obs_dict[f"{motor}.vel"] = state.get("velocity", 0.0)
+                obs_dict[f"{motor}.torque"] = state.get("torque", 0.0)
 
         # Capture images from cameras
         for cam_key, cam in self.cameras.items():

src/lerobot/rollout/configs.py

@@ -75,7 +75,7 @@ class SentryStrategyConfig(RolloutStrategyConfig):
     # Target video file size in MB for episode rotation.  Episodes are
     # saved once the estimated video duration would exceed this limit.
     # Defaults to DEFAULT_VIDEO_FILE_SIZE_IN_MB when set to None.
-    target_video_file_size_mb: float | None = None
+    target_video_file_size_mb: int | None = None
 
 
 @RolloutStrategyConfig.register_subclass("highlight")
@@ -90,7 +90,7 @@ class HighlightStrategyConfig(RolloutStrategyConfig):
     """
 
     ring_buffer_seconds: float = 10.0
-    ring_buffer_max_memory_mb: float = 1024.0
+    ring_buffer_max_memory_mb: int = 1024
     save_key: str = "s"
     push_key: str = "h"
 
@@ -150,7 +150,7 @@ class DAggerStrategyConfig(RolloutStrategyConfig):
     upload_every_n_episodes: int = 5
     # Target video file size in MB for episode rotation (record_autonomous
     # mode only).  Defaults to DEFAULT_VIDEO_FILE_SIZE_IN_MB when None.
-    target_video_file_size_mb: float | None = None
+    target_video_file_size_mb: int | None = None
     input_device: str = "keyboard"
     keyboard: DAggerKeyboardConfig = field(default_factory=DAggerKeyboardConfig)
     pedal: DAggerPedalConfig = field(default_factory=DAggerPedalConfig)
@@ -209,6 +209,12 @@ class RolloutConfig:
     # Rename map for mapping robot/dataset observation keys to policy keys
     rename_map: dict[str, str] = field(default_factory=dict)
 
+    # Hardware teardown
+    # When True (default), smoothly interpolate the robot back to the joint
+    # positions captured at startup before disconnecting.  Set to False to
+    # leave the robot in its final achieved pose at shutdown.
+    return_to_initial_position: bool = True
+
     # Torch compile
     use_torch_compile: bool = False
     torch_compile_backend: str = "inductor"

src/lerobot/rollout/context.py

@@ -27,7 +27,7 @@ from threading import Event
 
 import torch
 
-from lerobot.configs import FeatureType, PreTrainedConfig
+from lerobot.configs import FeatureType
 from lerobot.datasets import (
     LeRobotDataset,
     aggregate_pipeline_dataset_features,
@@ -43,6 +43,7 @@ from lerobot.processor import (
     make_default_processors,
     rename_stats,
 )
+from lerobot.processor.relative_action_processor import RelativeActionsProcessorStep
 from lerobot.robots import make_robot_from_config
 from lerobot.teleoperators import Teleoperator, make_teleoperator_from_config
 from lerobot.utils.feature_utils import combine_feature_dicts, hw_to_dataset_features
@@ -51,6 +52,7 @@ from .configs import BaseStrategyConfig, DAggerStrategyConfig, RolloutConfig
 from .inference import (
     InferenceEngine,
     RTCInferenceConfig,
+    SyncInferenceConfig,
     create_inference_engine,
 )
 from .robot_wrapper import ThreadSafeRobot
@@ -176,33 +178,26 @@ def build_rollout_context(
     policy_config = cfg.policy
     policy_class = get_policy_class(policy_config.type)
 
-    full_config = PreTrainedConfig.from_pretrained(cfg.policy.pretrained_path)
-    for attr in ("device", "use_amp"):
-        if hasattr(cfg.policy, attr) and hasattr(full_config, attr):
-            cli_val = getattr(cfg.policy, attr)
-            if cli_val is not None:
-                setattr(full_config, attr, cli_val)
+    if hasattr(policy_config, "compile_model"):
+        policy_config.compile_model = cfg.use_torch_compile
 
-    if hasattr(full_config, "compile_model"):
-        full_config.compile_model = cfg.use_torch_compile
-
-    if full_config.type == "vqbet" and cfg.device == "mps":
+    if policy_config.type == "vqbet" and cfg.device == "mps":
         raise NotImplementedError(
             "Current implementation of VQBeT does not support `mps` backend. "
             "Please use `cpu` or `cuda` backend."
         )
 
-    if full_config.use_peft:
+    if policy_config.use_peft:
         from peft import PeftConfig, PeftModel
 
-        peft_path = cfg.policy.pretrained_path
+        peft_path = policy_config.pretrained_path
         peft_config = PeftConfig.from_pretrained(peft_path)
         policy = policy_class.from_pretrained(
-            pretrained_name_or_path=peft_config.base_model_name_or_path, config=full_config
+            pretrained_name_or_path=peft_config.base_model_name_or_path, config=policy_config
         )
         policy = PeftModel.from_pretrained(policy, peft_path, config=peft_config)
     else:
-        policy = policy_class.from_pretrained(cfg.policy.pretrained_path, config=full_config)
+        policy = policy_class.from_pretrained(policy_config.pretrained_path, config=policy_config)
 
     if is_rtc:
         policy.config.rtc_config = cfg.inference.rtc
@@ -257,10 +252,12 @@ def build_rollout_context(
         teleop.connect()
         logger.info("Teleoperator connected")
 
-    # DAgger requires teleop with motor control capabilities (enable_torque,
-    # disable_torque, write_goal_positions).
-    # TODO(Steven): either enforce this (meaning all teleop must implement these methods) or
-    # user is responsible for moving the teleop to the same position as the robot when starting the correction.
+    # TODO(Steven): once Teleoperator motor-control methods are standardised
+    # (``enable_torque`` / ``disable_torque`` / ``write_goal_positions``), gate
+    # the DAgger strategy on their presence here and fail fast with a helpful
+    # message instead of relying on the operator to pre-align the leader by
+    # hand.  See :func:`DAggerStrategy._apply_transition` for the matching
+    # disabled call sites.
     # if isinstance(cfg.strategy, DAggerStrategyConfig) and teleop is not None:
     #     required_teleop_methods = ("enable_torque", "disable_torque", "write_goal_positions")
     #     missing = [m for m in required_teleop_methods if not callable(getattr(teleop, m, None))]
@@ -272,10 +269,13 @@ def build_rollout_context(
     #         )
 
     # --- 4. Features + action-key reconciliation ---------------------
-    # TODO(Steven): Only `.pos` joint features are used for policy inference — velocity and
-    # torque channels are observation-only and must be excluded from the state
-    # and action tensors that the policy sees.
+    # TODO(Steven):Only ``.pos`` joint features are routed to the policy as state and as the
+    # action target; velocity and torque channels (when present) are kept in
+    # the raw observation but excluded from the policy-facing tensors.
     all_obs_features = robot.observation_features
+    # ``observation_features`` values are either a tuple (camera shape) or the
+    # ``float`` type itself used as a sentinel for scalar motor features —
+    # see ``dict[str, type | tuple]`` annotation on ``Robot.observation_features``.
     observation_features_hw = {
         k: v
         for k, v in all_obs_features.items()
@@ -308,7 +308,9 @@ def build_rollout_context(
     # Validate visual features if no rename_map is active
     rename_map = cfg.rename_map
     if not rename_map:
-        expected_visuals = {k for k, v in full_config.input_features.items() if v.type == FeatureType.VISUAL}
+        expected_visuals = {
+            k for k, v in policy_config.input_features.items() if v.type == FeatureType.VISUAL
+        }
         provided_visuals = {
             f"observation.images.{k}" for k, v in robot.observation_features.items() if isinstance(v, tuple)
         }
@@ -353,6 +355,7 @@ def build_rollout_context(
                     "Use --dataset.repo_id=<user>/rollout_<name> for policy deployment datasets."
                 )
             cfg.dataset.stamp_repo_id()
+            target_video_mb = getattr(cfg.strategy, "target_video_file_size_mb", None)
             dataset = LeRobotDataset.create(
                 cfg.dataset.repo_id,
                 cfg.dataset.fps,
@@ -368,6 +371,7 @@ def build_rollout_context(
                 streaming_encoding=cfg.dataset.streaming_encoding,
                 encoder_queue_maxsize=cfg.dataset.encoder_queue_maxsize,
                 encoder_threads=cfg.dataset.encoder_threads,
+                video_files_size_in_mb=target_video_mb,
             )
 
     if dataset is not None:
@@ -391,6 +395,15 @@ def build_rollout_context(
         },
     )
 
+    if isinstance(cfg.inference, SyncInferenceConfig) and any(
+        isinstance(step, RelativeActionsProcessorStep) and step.enabled
+        for step in getattr(preprocessor, "steps", ())
+    ):
+        raise NotImplementedError(
+            "SyncInferenceEngine does not support policies with relative actions for now."
+            "Use --inference.type=rtc or remove relative action processor steps from the policy pipeline."
+        )
+
     # --- 7. Inference strategy (needs policy + pre/post + hardware) --
     logger.info(
         "Creating inference engine (type=%s)...",

src/lerobot/rollout/inference/__init__.py

@@ -14,8 +14,8 @@
 
 """Inference engine package — backend-agnostic action production.
 
-Concrete strategies (sync, RTC, …) expose the same small interface so
-rollout strategies never branch on the inference backend.
+Concrete backends (``sync``, ``rtc``, ...) expose the same small interface so
+rollout strategies never branch on which backend is in use.
 """
 
 from .base import InferenceEngine

src/lerobot/rollout/inference/base.py

@@ -15,8 +15,8 @@
 """Inference engine ABC.
 
 Rollout strategies consume actions through this small interface so they
-do not need to know whether the inference engine is synchronous, runs in
-a background thread (RTC), or comes from an external source.
+do not need to know whether inference happens inline on the control thread
+or asynchronously in a background thread (RTC).
 """
 
 from __future__ import annotations
@@ -29,9 +29,10 @@ import torch
 class InferenceEngine(abc.ABC):
     """Abstract backend for producing actions during rollout.
 
-    Subclasses decide whether inference happens inline, in a background
-    thread, or externally. The contract is minimal so new backends can
-    be added without touching rollout strategies.
+    Subclasses decide whether inference happens inline on the control
+    thread or asynchronously in a background thread.  The contract is
+    minimal so additional backends can be plugged in without touching
+    rollout strategies.
 
     Lifecycle
     ---------
@@ -43,8 +44,8 @@ class InferenceEngine(abc.ABC):
     -----------------
     ``get_action(obs_frame)`` — return the next action tensor, or
     ``None`` if none is available (e.g. async queue empty).  Sync
-    backends always compute from ``obs_frame``; async backends may
-    ignore it (they get observations via ``notify_observation``).
+    backends always compute from ``obs_frame``; async backends ignore
+    it (they receive observations via ``notify_observation``).
 
     Optional hooks
     --------------

src/lerobot/rollout/inference/factory.py

@@ -68,9 +68,8 @@ class SyncInferenceConfig(InferenceEngineConfig):
 class RTCInferenceConfig(InferenceEngineConfig):
     """Real-Time Chunking: async policy inference in a background thread."""
 
-    # ``RTCConfig`` is a small dataclass with default-only fields, so eagerly
-    # constructing one here costs nothing and keeps draccus' CLI surface flat
-    # (``--inference.rtc.execution_horizon=...`` etc.).  No need to lazy-init.
+    # Eagerly constructed so draccus exposes nested fields directly on the CLI
+    # (e.g. ``--inference.rtc.execution_horizon=...``).
     rtc: RTCConfig = field(default_factory=RTCConfig)
     queue_threshold: int = 30
 

src/lerobot/rollout/inference/rtc.py

@@ -32,18 +32,14 @@ from typing import Any
 import torch
 
 from lerobot.policies.pretrained import PreTrainedPolicy
-from lerobot.policies.rtc import ActionQueue, LatencyTracker
+from lerobot.policies.rtc import ActionQueue, LatencyTracker, reanchor_relative_rtc_prefix
 from lerobot.policies.rtc.configuration_rtc import RTCConfig
 from lerobot.policies.utils import prepare_observation_for_inference
 from lerobot.processor import (
     NormalizerProcessorStep,
     PolicyProcessorPipeline,
     RelativeActionsProcessorStep,
-    TransitionKey,
-    create_transition,
-    to_relative_actions,
 )
-from lerobot.utils.constants import OBS_STATE
 from lerobot.utils.feature_utils import build_dataset_frame
 
 from ..robot_wrapper import ThreadSafeRobot
@@ -66,35 +62,6 @@ _RTC_JOIN_TIMEOUT_S: float = 3.0
 # ---------------------------------------------------------------------------
 
 
-def _reanchor_relative_rtc_prefix(
-    prev_actions_absolute: torch.Tensor,
-    current_state: torch.Tensor,
-    relative_step: RelativeActionsProcessorStep,
-    normalizer_step: NormalizerProcessorStep | None,
-    policy_device: torch.device | str,
-) -> torch.Tensor:
-    """Convert absolute leftover actions into model-space for relative-action RTC policies.
-
-    When using relative actions, the RTC prefix (previous chunk's unexecuted tail)
-    is stored in absolute coordinates. Before feeding it back to the policy, this
-    helper re-expresses those actions relative to the robot's current joint state
-    and optionally normalizes them so the policy receives correctly scaled inputs.
-    """
-    state = current_state.detach().cpu()
-    if state.dim() == 1:
-        state = state.unsqueeze(0)
-
-    action_cpu = prev_actions_absolute.detach().cpu()
-    mask = relative_step._build_mask(action_cpu.shape[-1])
-    relative_actions = to_relative_actions(action_cpu, state, mask)
-
-    transition = create_transition(action=relative_actions)
-    if normalizer_step is not None:
-        transition = normalizer_step(transition)
-
-    return transition[TransitionKey.ACTION].to(policy_device)
-
-
 def _normalize_prev_actions_length(prev_actions: torch.Tensor, target_steps: int) -> torch.Tensor:
     """Pad or truncate RTC prefix actions to a fixed length for stable compiled inference."""
     if prev_actions.ndim != 2:
@@ -109,21 +76,6 @@ def _normalize_prev_actions_length(prev_actions: torch.Tensor, target_steps: int
     return padded
 
 
-def _get_current_raw_state(
-    relative_step: RelativeActionsProcessorStep,
-    fallback_state: torch.Tensor | None,
-) -> torch.Tensor | None:
-    """Return the current raw state cached by the relative-action step.
-
-    ``RelativeActionsProcessorStep`` caches the observation state before any
-    observation normalization. Re-anchoring RTC leftovers must use that raw
-    state rather than the normalized observation that the policy consumes.
-    """
-    if relative_step._last_state is not None:
-        return relative_step._last_state
-    return fallback_state
-
-
 # ---------------------------------------------------------------------------
 # RTCInferenceEngine
 # ---------------------------------------------------------------------------
@@ -333,15 +285,15 @@ class RTCInferenceEngine(InferenceEngine):
                         preprocessed = self._preprocessor(obs_batch)
 
                         if prev_actions is not None and self._relative_step is not None:
-                            state_tensor = _get_current_raw_state(
-                                self._relative_step, obs_batch.get(OBS_STATE)
-                            )
-                            if state_tensor is not None:
+                            # Rebase against the raw cached state so the leftover tail stays in
+                            # the training-time coordinate frame.
+                            raw_state = self._relative_step.get_cached_state()
+                            if raw_state is not None:
                                 prev_abs = queue.get_processed_left_over()
                                 if prev_abs is not None and prev_abs.numel() > 0:
-                                    prev_actions = _reanchor_relative_rtc_prefix(
+                                    prev_actions = reanchor_relative_rtc_prefix(
                                         prev_actions_absolute=prev_abs,
-                                        current_state=state_tensor,
+                                        current_state=raw_state,
                                         relative_step=self._relative_step,
                                         normalizer_step=self._normalizer_step,
                                         policy_device=policy_device,

src/lerobot/rollout/inference/sync.py

@@ -17,7 +17,6 @@
 from __future__ import annotations
 
 import logging
-from collections import deque
 from contextlib import nullcontext
 from copy import copy
 
@@ -32,12 +31,27 @@ from .base import InferenceEngine
 logger = logging.getLogger(__name__)
 
 
+# TODO(Steven): support relative-action policies.  The per-tick flow refreshes
+# ``RelativeActionsProcessorStep._last_state`` every call, so cached chunk
+# actions popped on later ticks get reanchored to the *current* robot state and
+# absolute targets drift through the chunk.  Relative-action policies are
+# rejected at context-build time today; RTC postprocesses the whole chunk and
+# is unaffected.
+#
+# Candidate fix: drive the policy via ``predict_action_chunk`` and serve a
+# local FIFO of postprocessed actions.  Eliminates drift by construction and
+# saves per-tick pre/post work, but bypasses ``select_action`` — needs
+# fallbacks for SAC (raises), ACT temporal ensembling (ensembler lives in
+# ``select_action``), and Diffusion-family (obs-history queues populated as a
+# side effect of ``select_action``).
+
+
 class SyncInferenceEngine(InferenceEngine):
     """Inline synchronous inference: compute one action per call.
 
-    ``get_action`` runs the full policy pipeline when its local action
-    queue is empty, postprocesses the whole predicted chunk immediately,
-    and then returns one already-postprocessed CPU action at a time.
+    ``get_action`` runs the full policy pipeline (pre/post-processor +
+    ``select_action``) on the given observation frame and returns a
+    CPU action tensor reordered to match the dataset action keys.
     """
 
     def __init__(
@@ -59,8 +73,6 @@ class SyncInferenceEngine(InferenceEngine):
         self._task = task
         self._device = torch.device(device or "cpu")
         self._robot_type = robot_type
-        self._processed_action_queue: deque[torch.Tensor] = deque()
-
         logger.info(
             "SyncInferenceEngine initialized (device=%s, action_keys=%d)",
             self._device,
@@ -81,28 +93,9 @@ class SyncInferenceEngine(InferenceEngine):
         self._policy.reset()
         self._preprocessor.reset()
         self._postprocessor.reset()
-        self._processed_action_queue.clear()
-
-    def _enqueue_processed_chunk(self, action_chunk: torch.Tensor) -> None:
-        """Convert a postprocessed action chunk into ordered per-step CPU tensors."""
-        if action_chunk.ndim == 2:
-            action_chunk = action_chunk.unsqueeze(0)
-
-        n_action_steps = getattr(self._policy.config, "n_action_steps", action_chunk.shape[1])
-        action_chunk = action_chunk[:, : min(n_action_steps, action_chunk.shape[1])]
-
-        for action in action_chunk.squeeze(0):
-            action_tensor = action.cpu()
-            action_dict = make_robot_action(action_tensor, self._dataset_features)
-            ordered_action = torch.tensor(
-                [action_dict[k] for k in self._ordered_action_keys], dtype=action_tensor.dtype
-            )
-            self._processed_action_queue.append(ordered_action)
 
     def get_action(self, obs_frame: dict | None) -> torch.Tensor | None:
         """Run the full inference pipeline on ``obs_frame`` and return an action tensor."""
-        if self._processed_action_queue:
-            return self._processed_action_queue.popleft().clone()
         if obs_frame is None:
             return None
         # Shallow copy is intentional: the caller (`send_next_action`) builds
@@ -119,10 +112,11 @@ class SyncInferenceEngine(InferenceEngine):
                 observation, self._device, self._task, self._robot_type
             )
             observation = self._preprocessor(observation)
-            action_chunk = self._policy.predict_action_chunk(observation)
-            processed_chunk = self._postprocessor(action_chunk)
+            action = self._policy.select_action(observation)
+            action = self._postprocessor(action)
+        action_tensor = action.squeeze(0).cpu()
 
-        self._enqueue_processed_chunk(processed_chunk)
-        if not self._processed_action_queue:
-            return None
-        return self._processed_action_queue.popleft().clone()
+        # Reorder to match dataset action ordering so the caller can treat
+        # the returned tensor uniformly across backends.
+        action_dict = make_robot_action(action_tensor, self._dataset_features)
+        return torch.tensor([action_dict[k] for k in self._ordered_action_keys])

src/lerobot/rollout/ring_buffer.py

@@ -47,7 +47,7 @@ class RolloutRingBuffer:
         count.
     """
 
-    def __init__(self, max_seconds: float = 30.0, max_memory_mb: float = 2048.0, fps: float = 30.0) -> None:
+    def __init__(self, max_seconds: float = 30.0, max_memory_mb: int = 2048, fps: float = 30.0) -> None:
         self._max_frames = int(max_seconds * fps)
         self._max_bytes = int(max_memory_mb * 1024 * 1024)
         self._buffer: deque[dict] = deque(maxlen=self._max_frames)

src/lerobot/rollout/strategies/base.py

@@ -23,6 +23,7 @@ from lerobot.utils.robot_utils import precise_sleep
 
 from ..context import RolloutContext
 from .core import RolloutStrategy, send_next_action
+from .display import BaseDisplay
 
 logger = logging.getLogger(__name__)
 
@@ -38,6 +39,8 @@ class BaseStrategy(RolloutStrategy):
         """Initialise the inference engine."""
         self._init_engine(ctx)
         logger.info("Base strategy ready")
+        self._display = BaseDisplay(duration=ctx.runtime.cfg.duration)
+        self._display.show_banner()
 
     def run(self, ctx: RolloutContext) -> None:
         """Run the autonomous control loop until shutdown or duration expires."""
@@ -47,12 +50,8 @@ class BaseStrategy(RolloutStrategy):
         interpolator = self._interpolator
 
         control_interval = interpolator.get_control_interval(cfg.fps)
-        observation_interval = 1.0 / cfg.fps
 
         start_time = time.perf_counter()
-        next_observation_time = 0.0
-        obs = None
-        obs_processed = None
         engine.resume()
         logger.info("Base strategy control loop started")
 
@@ -63,18 +62,12 @@ class BaseStrategy(RolloutStrategy):
                 logger.info("Duration limit reached (%.0fs)", cfg.duration)
                 break
 
-            if obs is None or loop_start >= next_observation_time:
-                obs = robot.get_observation()
-                obs_processed = ctx.processors.robot_observation_processor(obs)
-                engine.notify_observation(obs_processed)
-                next_observation_time = loop_start + observation_interval
+            obs = robot.get_observation()
+            obs_processed = self._process_observation_and_notify(ctx.processors, obs)
 
             if self._handle_warmup(cfg.use_torch_compile, loop_start, control_interval):
                 continue
 
-            if obs_processed is None:
-                continue
-
             action_dict = send_next_action(obs_processed, obs, ctx, interpolator)
             self._log_telemetry(obs_processed, action_dict, ctx.runtime)
 
@@ -82,11 +75,12 @@ class BaseStrategy(RolloutStrategy):
             if (sleep_t := control_interval - dt) > 0:
                 precise_sleep(sleep_t)
             else:
-                logger.warning(
-                    f"Record loop is running slower ({1 / dt:.1f} Hz) than the target FPS ({cfg.fps} Hz). Dataset frames might be dropped and robot control might be unstable. Common causes are: 1) Camera FPS not keeping up 2) Policy inference taking too long 3) CPU starvation"
-                )
+                self._warn_slow_loop(dt, control_interval, cfg.fps)
 
     def teardown(self, ctx: RolloutContext) -> None:
         """Disconnect hardware and stop inference."""
-        self._teardown_hardware(ctx.hardware)
+        self._teardown_hardware(
+            ctx.hardware,
+            return_to_initial_position=ctx.runtime.cfg.return_to_initial_position,
+        )
         logger.info("Base strategy teardown complete")

src/lerobot/rollout/strategies/core.py

@@ -32,7 +32,8 @@ from ..inference import InferenceEngine
 
 if TYPE_CHECKING:
     from ..configs import RolloutStrategyConfig
-    from ..context import HardwareContext, RolloutContext, RuntimeContext
+    from ..context import HardwareContext, ProcessorContext, RolloutContext, RuntimeContext
+    from .display import RolloutStatusDisplay
 
 logger = logging.getLogger(__name__)
 
@@ -50,6 +51,18 @@ class RolloutStrategy(abc.ABC):
         self._engine: InferenceEngine | None = None
         self._interpolator: ActionInterpolator | None = None
         self._warmup_flushed: bool = False
+        self._cached_obs_processed: dict | None = None
+        self._display: RolloutStatusDisplay | None = None
+
+    def _warn_slow_loop(self, dt: float, control_interval: float, fps: float) -> None:
+        """Warn when the control loop runs slower than the target FPS."""
+        if dt > control_interval:
+            logger.warning(
+                "Control loop running slower (%.1f Hz) than target (%.0f Hz). "
+                "Possible causes: camera FPS not keeping up, slow policy inference, CPU starvation.",
+                1 / dt,
+                fps,
+            )
 
     def _init_engine(self, ctx: RolloutContext) -> None:
         """Attach the inference engine and action interpolator, then start the backend.
@@ -65,8 +78,32 @@ class RolloutStrategy(abc.ABC):
         self._engine.reset()
         self._engine.start()
         self._warmup_flushed = False
+        self._cached_obs_processed = None
         logger.info("Inference engine started")
 
+    def _process_observation_and_notify(self, processors: ProcessorContext, obs_raw: dict) -> dict:
+        """Run the observation processor and notify the engine — throttled to policy ticks.
+
+        Callers are responsible for calling ``robot.get_observation()`` every loop
+        iteration so ``obs_raw`` stays fresh for the action post-processor.  This
+        helper gates only the comparatively expensive bits — the processor pipeline
+        and ``engine.notify_observation`` — to fire when the interpolator signals
+        it needs a new action (once per ``interpolation_multiplier`` ticks).  On
+        interpolated ticks the cached ``obs_processed`` is reused.
+
+        With ``interpolation_multiplier == 1`` this is equivalent to the unthrottled
+        path: ``needs_new_action()`` is True every tick.
+
+        The cache is implicitly invalidated whenever ``interpolator.reset()`` is
+        called (warmup completion, DAgger phase transitions back to AUTONOMOUS),
+        because reset makes ``needs_new_action()`` return True on the next call.
+        """
+        if self._cached_obs_processed is None or self._interpolator.needs_new_action():
+            obs_processed = processors.robot_observation_processor(obs_raw)
+            self._engine.notify_observation(obs_processed)
+            self._cached_obs_processed = obs_processed
+        return self._cached_obs_processed
+
     def _handle_warmup(self, use_torch_compile: bool, loop_start: float, control_interval: float) -> bool:
         """Handle torch.compile warmup phase.
 
@@ -91,16 +128,20 @@ class RolloutStrategy(abc.ABC):
             engine.resume()
         return False
 
-    def _teardown_hardware(self, hw: HardwareContext) -> None:
-        """Stop the inference engine, return robot to initial position, and disconnect hardware."""
+    def _teardown_hardware(self, hw: HardwareContext, return_to_initial_position: bool = True) -> None:
+        """Stop the inference engine, optionally return robot to initial position, and disconnect hardware."""
         if self._engine is not None:
             logger.info("Stopping inference engine...")
             self._engine.stop()
         robot = hw.robot_wrapper.inner
         if robot.is_connected:
-            if hw.initial_position:
+            if return_to_initial_position and hw.initial_position:
                 logger.info("Returning robot to initial position before shutdown...")
                 self._return_to_initial_position(hw)
+            elif not return_to_initial_position:
+                logger.info(
+                    "Skipping return-to-initial-position (disabled by config); leaving robot in final pose."
+                )
             logger.info("Disconnecting robot...")
             robot.disconnect()
         teleop = hw.teleop
@@ -194,7 +235,7 @@ def estimate_max_episode_seconds(
     The estimate ignores codec-specific settings (CRF, preset) on purpose:
     we only need a rough lower bound on bitrate, not a precise prediction.
 
-    Falls back to 600 s (10 min) when no video features are present.
+    Falls back to 300 s (5 min) when no video features are present.
     """
     # 0.1 bits-per-pixel is a *low* estimate for CRF-30 streaming video of
     # robot footage (real-world is typically 0.1 – 0.3 bpp).  Under-
@@ -208,16 +249,16 @@ def estimate_max_episode_seconds(
         if feat.get("dtype") == "video":
             shape = feat.get("shape", ())
 
-            # Assuming shape could be (C, H, W) or (T, C, H, W)
-            # We want to extract the spatial dimensions.
-            if len(shape) >= 3:
-                h, w = shape[-2], shape[-1]
-                pixels = h * w
-                if pixels > 0:
-                    camera_pixels.append(pixels)
+            # (H, W, C) — bits-per-pixel is a per-spatial-pixel metric,
+            # so we exclude the channel dimension from the count.
+            if len(shape) == 3:
+                pixels = shape[0] * shape[1]
+                camera_pixels.append(pixels)
+            else:
+                raise ValueError(f"Unexpected video feature shape: {shape}")
 
     if not camera_pixels:
-        return 600.0
+        return 300.0
 
     # Use the smallest camera: it produces the lowest bitrate and therefore
     # takes the longest to reach the target — the conservative choice.
@@ -227,7 +268,7 @@ def estimate_max_episode_seconds(
 
     # Guard against division by zero just in case
     if bytes_per_second <= 0:
-        return 600.0
+        return 300.0
 
     return (target_size_mb * 1024 * 1024) / bytes_per_second
 

src/lerobot/rollout/strategies/dagger.py

@@ -24,14 +24,22 @@ the ``input_device`` config field.  Each device exposes three actions:
     1. **pause_resume** — Toggle policy execution (AUTONOMOUS <-> PAUSED).
     2. **correction**   — Toggle correction recording (PAUSED <-> CORRECTING).
     3. **upload**        — Push dataset to hub on demand (corrections-only mode).
-    ESC (keyboard only)  — Stop session.
+    ESC (keyboard only) — Stop session.
 
-Recording Modes:
+Recording modes:
     ``record_autonomous=True``:  Sentry-like continuous recording with
         time-based episode rotation.  Both autonomous and correction
         frames are recorded; corrections tagged ``intervention=True``.
     ``record_autonomous=False``: Only correction windows are recorded.
         Each correction (start to stop) becomes one episode.
+
+Teleoperator handover:
+    On AUTONOMOUS → PAUSED, actuated teleops (those with non-empty
+    ``feedback_features``, e.g. SO-101, OpenArmMini) are smoothly driven to
+    the follower's last position via ``send_feedback`` so the operator takes
+    over without a jerk.  Non-actuated teleops cannot be driven,
+    so on PAUSED → CORRECTING the follower is instead slid to the teleop's
+    current pose before the correction begins.
 """
 
 from __future__ import annotations
@@ -63,6 +71,7 @@ from ..configs import DAggerKeyboardConfig, DAggerPedalConfig, DAggerStrategyCon
 from ..context import RolloutContext
 from ..robot_wrapper import ThreadSafeRobot
 from .core import RolloutStrategy, estimate_max_episode_seconds, safe_push_to_hub, send_next_action
+from .display import DAggerDisplay
 
 PYNPUT_AVAILABLE = _pynput_available
 keyboard = None
@@ -168,15 +177,27 @@ class DAggerEvents:
 # ---------------------------------------------------------------------------
 
 
-# TODO(Steven): either enforce this (meaning all teleop must implement these methods) or
-# user is responsible for moving the teleop to the same position as the robot when starting the correction.
-def _teleop_smooth_move_to(
-    teleop: Teleoperator, target_pos: dict, duration_s: float = 2.0, fps: int = 50
-) -> None:
-    """Smoothly move teleop to target position via linear interpolation.
+def _teleop_supports_feedback(teleop: Teleoperator) -> bool:
+    """Return True when the teleop can receive position feedback (is actuated).
+    TODO(Maxime): See if it is possible to unify this interface across teleops instead of duck-typing.
+    """
+    return (
+        bool(teleop.feedback_features)
+        and hasattr(teleop, "disable_torque")
+        and hasattr(teleop, "enable_torque")
+    )
 
-    Requires the teleoperator to support motor control methods
-    (``enable_torque``, ``write_goal_positions``, ``get_action``).
+
+def _teleop_smooth_move_to(
+    teleop: Teleoperator, target_pos: dict, duration_s: float = 2.0, fps: int = 30
+) -> None:
+    """Smoothly move an actuated teleop to ``target_pos`` via linear interpolation.
+
+    Requires the teleoperator to support feedback
+    (i.e. have non-empty ``feedback_features`` and implement ``disable_torque`` / ``enable_torque``).
+
+    TODO(Maxime): This blocks up to ``duration_s`` seconds, during this time
+    the follower robot doesn't receive new actions, this could be an issue on LeKiwi.
     """
     teleop.enable_torque()
     current = teleop.get_action()
@@ -184,13 +205,28 @@ def _teleop_smooth_move_to(
 
     for step in range(steps + 1):
         t = step / steps
-        interp = {}
-        for k in current:
-            if k in target_pos:
-                interp[k] = current[k] * (1 - t) + target_pos[k] * t
-            else:
-                interp[k] = current[k]
-        teleop.write_goal_positions(interp)
+        interp = {
+            k: current[k] * (1 - t) + target_pos[k] * t if k in target_pos else current[k] for k in current
+        }
+        teleop.send_feedback(interp)
+        time.sleep(1 / fps)
+
+
+def _follower_smooth_move_to(
+    robot: ThreadSafeRobot, current: dict, target: dict, duration_s: float = 1.0, fps: int = 30
+) -> None:
+    """Smoothly move the follower robot from ``current`` to ``target`` action.
+
+    Used when the teleop is non-actuated: instead of driving the leader arm
+    to the follower, we bring the follower to the teleop's current pose.
+    Both ``current`` and ``target`` must be in robot-action key space.
+    """
+    steps = max(int(duration_s * fps), 1)
+
+    for step in range(steps + 1):
+        t = step / steps
+        interp = {k: current[k] * (1 - t) + target[k] * t if k in target else current[k] for k in current}
+        robot.send_action(interp)
         time.sleep(1 / fps)
 
 
@@ -251,7 +287,7 @@ def _init_dagger_keyboard(events: DAggerEvents, cfg: DAggerKeyboardConfig):
 
     listener = keyboard.Listener(on_press=on_press)
     listener.start()
-    logger.info(
+    logger.debug(
         "DAgger keyboard listener started (pause_resume='%s', correction='%s', upload='%s', ESC=stop)",
         cfg.pause_resume,
         cfg.correction,
@@ -335,6 +371,28 @@ class DAggerStrategy(RolloutStrategy):
             self._episode_duration_s,
         )
 
+        if self.config.input_device == "keyboard":
+            kb = self.config.keyboard
+            pause_key, correction_key, upload_key = (
+                kb.pause_resume.upper(),
+                kb.correction.upper(),
+                kb.upload.upper(),
+            )
+        else:
+            pb = self.config.pedal
+            pause_key, correction_key, upload_key = pb.pause_resume, pb.correction, pb.upload
+
+        self._display = DAggerDisplay(
+            record_autonomous=self.config.record_autonomous,
+            num_episodes=self.config.num_episodes,
+            episode_duration_s=self._episode_duration_s,
+            input_device=self.config.input_device,
+            pause_key=pause_key,
+            correction_key=correction_key,
+            upload_key=upload_key,
+        )
+        self._display.show_banner()
+
     def run(self, ctx: RolloutContext) -> None:
         """Run DAgger episodes with human-in-the-loop intervention."""
         if self.config.record_autonomous:
@@ -371,7 +429,10 @@ class DAggerStrategy(RolloutStrategy):
                     logger.info("Dataset uploaded to hub")
                     log_say("Dataset uploaded to hub", play_sounds)
 
-        self._teardown_hardware(ctx.hardware)
+        self._teardown_hardware(
+            ctx.hardware,
+            return_to_initial_position=ctx.runtime.cfg.return_to_initial_position,
+        )
         logger.info("DAgger strategy teardown complete")
 
     # ------------------------------------------------------------------
@@ -403,10 +464,8 @@ class DAggerStrategy(RolloutStrategy):
         engine.reset()
         interpolator.reset()
         events.reset()
-        # TODO(Steven): either enforce this (meaning all teleop must implement these methods) or
-        # user is responsible for moving the teleop to the same position as the robot when starting the correction.
-        # teleop.disable_torque()
         engine.resume()
+        self._display.show_state(DAggerPhase.AUTONOMOUS)
 
         last_action: dict[str, Any] | None = None
         record_tick = 0
@@ -429,24 +488,36 @@ class DAggerStrategy(RolloutStrategy):
                     transition = events.consume_transition()
                     if transition is not None:
                         old_phase, new_phase = transition
-                        self._apply_transition(old_phase, new_phase, engine, interpolator, robot, teleop)
-                        last_action = None
+                        self._apply_transition(
+                            old_phase,
+                            new_phase,
+                            engine,
+                            interpolator,
+                            ctx,
+                            last_action,
+                        )
+                        self._display.show_state(new_phase)
+                        if new_phase == DAggerPhase.AUTONOMOUS:
+                            last_action = None
 
                     phase = events.phase
                     obs = robot.get_observation()
-                    obs_processed = ctx.processors.robot_observation_processor(obs)
-                    obs_frame = build_dataset_frame(features, obs_processed, prefix=OBS_STR)
 
                     # --- CORRECTING: human teleop control ---
+                    # TODO(Steven): teleop runs at the same FPS as the policy. To
+                    # decouple the two, sample teleop at its native rate and
+                    # interpolate to the control loop's tick rate.
                     if phase == DAggerPhase.CORRECTING:
+                        obs_processed = ctx.processors.robot_observation_processor(obs)
                         teleop_action = teleop.get_action()
                         processed_teleop = ctx.processors.teleop_action_processor((teleop_action, obs))
                         robot_action_to_send = ctx.processors.robot_action_processor((processed_teleop, obs))
                         robot.send_action(robot_action_to_send)
                         last_action = robot_action_to_send
                         self._log_telemetry(obs_processed, processed_teleop, ctx.runtime)
-                        action_frame = build_dataset_frame(features, processed_teleop, prefix=ACTION)
                         if record_tick % record_stride == 0:
+                            obs_frame = build_dataset_frame(features, obs_processed, prefix=OBS_STR)
+                            action_frame = build_dataset_frame(features, processed_teleop, prefix=ACTION)
                             frame = {
                                 **obs_frame,
                                 **action_frame,
@@ -463,7 +534,7 @@ class DAggerStrategy(RolloutStrategy):
 
                     # --- AUTONOMOUS: policy control ---
                     else:
-                        engine.notify_observation(obs_processed)
+                        obs_processed = self._process_observation_and_notify(ctx.processors, obs)
 
                         if self._handle_warmup(cfg.use_torch_compile, loop_start, control_interval):
                             continue
@@ -472,8 +543,9 @@ class DAggerStrategy(RolloutStrategy):
                         if action_dict is not None:
                             self._log_telemetry(obs_processed, action_dict, ctx.runtime)
                             last_action = ctx.processors.robot_action_processor((action_dict, obs))
-                            action_frame = build_dataset_frame(features, action_dict, prefix=ACTION)
                             if record_tick % record_stride == 0:
+                                obs_frame = build_dataset_frame(features, obs_processed, prefix=OBS_STR)
+                                action_frame = build_dataset_frame(features, action_dict, prefix=ACTION)
                                 frame = {
                                     **obs_frame,
                                     **action_frame,
@@ -483,9 +555,9 @@ class DAggerStrategy(RolloutStrategy):
                                 dataset.add_frame(frame)
                             record_tick += 1
 
-                    # Episode rotation derived from video file-size target.
-                    # Do NOT save mid-correction — wait for the correction
-                    # to finish so the episode boundary is clean.
+                    # Episode rotation derived from the video file-size target.
+                    # Saving is deferred while a correction is ongoing so the
+                    # episode boundary lands on a clean autonomous frame.
                     elapsed = time.perf_counter() - episode_start
                     if elapsed >= episode_duration_s and phase != DAggerPhase.CORRECTING:
                         with self._episode_lock:
@@ -509,16 +581,11 @@ class DAggerStrategy(RolloutStrategy):
                     if (sleep_t := control_interval - dt) > 0:
                         precise_sleep(sleep_t)
                     else:
-                        logger.warning(
-                            f"Record loop is running slower ({1 / dt:.1f} Hz) than the target FPS ({cfg.fps} Hz). Dataset frames might be dropped and robot control might be unstable. Common causes are: 1) Camera FPS not keeping up 2) Policy inference taking too long 3) CPU starvation"
-                        )
+                        self._warn_slow_loop(dt, control_interval, cfg.fps)
 
             finally:
                 logger.info("DAgger continuous control loop ended — pausing engine")
                 engine.pause()
-                # TODO(Steven): either enforce this (meaning all teleop must implement these methods) or
-                # user is responsible for moving the teleop to the same position as the robot when starting the correction.
-                # teleop.disable_torque()
                 with contextlib.suppress(Exception):
                     with self._episode_lock:
                         dataset.save_episode()
@@ -554,10 +621,8 @@ class DAggerStrategy(RolloutStrategy):
         engine.reset()
         interpolator.reset()
         events.reset()
-        # TODO(Steven): either enforce this (meaning all teleop must implement these methods) or
-        # user is responsible for moving the teleop to the same position as the robot when starting the correction.
-        # teleop.disable_torque()
         engine.resume()
+        self._display.show_state(DAggerPhase.AUTONOMOUS)
 
         last_action: dict[str, Any] | None = None
         start_time = time.perf_counter()
@@ -584,8 +649,17 @@ class DAggerStrategy(RolloutStrategy):
                     transition = events.consume_transition()
                     if transition is not None:
                         old_phase, new_phase = transition
-                        self._apply_transition(old_phase, new_phase, engine, interpolator, robot, teleop)
-                        last_action = None
+                        self._apply_transition(
+                            old_phase,
+                            new_phase,
+                            engine,
+                            interpolator,
+                            ctx,
+                            last_action,
+                        )
+                        self._display.show_state(new_phase)
+                        if new_phase == DAggerPhase.AUTONOMOUS:
+                            last_action = None
 
                         # Correction ended -> save episode (blocking if not streaming)
                         if old_phase == DAggerPhase.CORRECTING and new_phase == DAggerPhase.PAUSED:
@@ -608,10 +682,13 @@ class DAggerStrategy(RolloutStrategy):
 
                     phase = events.phase
                     obs = robot.get_observation()
-                    obs_processed = ctx.processors.robot_observation_processor(obs)
 
                     # --- CORRECTING: human teleop control + recording ---
+                    # TODO(Steven): teleop runs at the same FPS as the policy. To
+                    # decouple the two, sample teleop at its native rate and
+                    # interpolate to the control loop's tick rate.
                     if phase == DAggerPhase.CORRECTING:
+                        obs_processed = ctx.processors.robot_observation_processor(obs)
                         teleop_action = teleop.get_action()
                         processed_teleop = ctx.processors.teleop_action_processor((teleop_action, obs))
                         robot_action_to_send = ctx.processors.robot_action_processor((processed_teleop, obs))
@@ -619,9 +696,9 @@ class DAggerStrategy(RolloutStrategy):
                         last_action = robot_action_to_send
                         self._log_telemetry(obs_processed, processed_teleop, ctx.runtime)
 
-                        obs_frame = build_dataset_frame(features, obs_processed, prefix=OBS_STR)
-                        action_frame = build_dataset_frame(features, processed_teleop, prefix=ACTION)
                         if record_tick % record_stride == 0:
+                            obs_frame = build_dataset_frame(features, obs_processed, prefix=OBS_STR)
+                            action_frame = build_dataset_frame(features, processed_teleop, prefix=ACTION)
                             dataset.add_frame(
                                 {
                                     **obs_frame,
@@ -639,7 +716,7 @@ class DAggerStrategy(RolloutStrategy):
 
                     # --- AUTONOMOUS: policy control (no recording) ---
                     else:
-                        engine.notify_observation(obs_processed)
+                        obs_processed = self._process_observation_and_notify(ctx.processors, obs)
 
                         if self._handle_warmup(cfg.use_torch_compile, loop_start, control_interval):
                             continue
@@ -653,16 +730,11 @@ class DAggerStrategy(RolloutStrategy):
                     if (sleep_t := control_interval - dt) > 0:
                         precise_sleep(sleep_t)
                     else:
-                        logger.warning(
-                            f"Record loop is running slower ({1 / dt:.1f} Hz) than the target FPS ({cfg.fps} Hz). Dataset frames might be dropped and robot control might be unstable. Common causes are: 1) Camera FPS not keeping up 2) Policy inference taking too long 3) CPU starvation"
-                        )
+                        self._warn_slow_loop(dt, control_interval, cfg.fps)
 
             finally:
                 logger.info("DAgger corrections-only loop ended — pausing engine")
                 engine.pause()
-                # TODO(Steven): either enforce this (meaning all teleop must implement these methods) or
-                # user is responsible for moving the teleop to the same position as the robot when starting the correction.
-                # teleop.disable_torque()
                 with contextlib.suppress(Exception):
                     with self._episode_lock:
                         dataset.save_episode()
@@ -679,35 +751,71 @@ class DAggerStrategy(RolloutStrategy):
         new_phase: DAggerPhase,
         engine,
         interpolator,
-        robot: ThreadSafeRobot,
-        teleop: Teleoperator,
+        ctx: RolloutContext,
+        prev_action: dict | None,
     ) -> None:
-        """Execute side-effects for a validated phase transition."""
+        """Execute side-effects for a validated phase transition, including smooth handovers.
+
+        AUTONOMOUS -> PAUSED (actuated teleop):
+            Pause the engine, then drive the leader arm to the follower's last
+            commanded position so the operator takes over without a jerk.
+
+        PAUSED -> CORRECTING (non-actuated teleop):
+            Slide the follower to the teleop's current pose so the robot meets
+            the operator's hand rather than jumping to it on the first frame.
+
+        CORRECTING -> PAUSED (actuated teleop):
+            Re-enable torque to hold position after correction.
+            This will be potentially useful if cancelling the correction recording
+
+        PAUSED -> AUTONOMOUS:
+            Reset and resume the inference engine.
+        """
+        teleop = ctx.hardware.teleop
+        robot = ctx.hardware.robot_wrapper
+
         logger.info("Phase transition: %s -> %s", old_phase.value, new_phase.value)
         if old_phase == DAggerPhase.AUTONOMOUS and new_phase == DAggerPhase.PAUSED:
-            logger.info("Pausing engine — robot holds position")
+            logger.info("Pausing engine - robot holds position")
             engine.pause()
-            obs = robot.get_observation()
-            _robot_pos = {
-                k: v for k, v in obs.items() if k.endswith(".pos") and k in robot.observation_features
-            }
-            # TODO(Steven): either enforce this (meaning all teleop must implement these methods) or
-            # user is responsible for moving the teleop to the same position as the robot when starting the correction.
-            # Consider also a method that moves the robot to the teleop smoothly (similar to what we do at HW shutdown).
-            # _teleop_smooth_move_to(teleop, robot_pos, duration_s=2.0, fps=50)
 
-        elif new_phase == DAggerPhase.CORRECTING:
-            logger.info("Entering correction mode — human teleop control")
-            # TODO(Steven): either enforce this (meaning all teleop must implement these methods) or
-            # user is responsible for moving the teleop to the same position as the robot when starting the correction.
-            # teleop.disable_torque()
+            if _teleop_supports_feedback(teleop) and prev_action is not None:
+                # TODO(Maxime): prev_action is in robot action key space (output of robot_action_processor).
+                # send_feedback expects teleop feedback key space. For homogeneous setups (e.g. SO-101
+                # leader + SO-101 follower) the keys are identical so this works. If the processor pipeline
+                # does non-trivial key renaming (e.g. a rename_map on action keys), the interpolation in
+                # _teleop_smooth_move_to silently no-ops and the arm doesn't move.
+                logger.info("Smooth handover: moving leader arm to follower position")
+                _teleop_smooth_move_to(teleop, prev_action)
+
+        elif old_phase == DAggerPhase.PAUSED and new_phase == DAggerPhase.CORRECTING:
+            logger.info("Entering correction mode - human teleop control")
+            if not _teleop_supports_feedback(teleop) and prev_action is not None:
+                logger.info("Smooth handover: sliding follower to teleop position")
+                obs = robot.get_observation()
+                teleop_action = teleop.get_action()
+                processed = ctx.processors.teleop_action_processor((teleop_action, obs))
+                target = ctx.processors.robot_action_processor((processed, obs))
+                _follower_smooth_move_to(robot, prev_action, target)
+
+            # unlock the teleop for human control
+            if _teleop_supports_feedback(teleop):
+                teleop.disable_torque()
+
+        elif old_phase == DAggerPhase.CORRECTING and new_phase == DAggerPhase.PAUSED:
+            if _teleop_supports_feedback(teleop):
+                teleop.enable_torque()
 
         elif new_phase == DAggerPhase.AUTONOMOUS:
-            logger.info("Resuming autonomous mode — resetting engine and interpolator")
+            logger.info("Resuming autonomous mode - resetting engine and interpolator")
             interpolator.reset()
             engine.reset()
             engine.resume()
 
+            # release teleop before resuming the policy
+            if _teleop_supports_feedback(teleop):
+                teleop.disable_torque()
+
     # ------------------------------------------------------------------
     # Background push (shared by both modes)
     # ------------------------------------------------------------------

src/lerobot/rollout/strategies/display.py

@@ -0,0 +1,263 @@
+# Copyright 2025 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Console status display for rollout strategies.
+
+One subclass per strategy — static states/controls are declared as class
+constants; runtime-dependent values are passed to ``__init__``.
+
+In each strategy's ``setup()``:
+
+    self._display = DAggerDisplay(
+        record_autonomous=self.config.record_autonomous,
+        num_episodes=self.config.num_episodes,
+        episode_duration_s=self._episode_duration_s,
+        input_device=self.config.input_device,
+        pause_key="SPACE",
+        correction_key="TAB",
+        upload_key="ENTER",
+    )
+    self._display.show_banner()
+
+On each state transition:
+
+    self._display.show_state("correcting")
+"""
+
+from __future__ import annotations
+
+import enum
+import sys
+from dataclasses import dataclass
+
+
+def _supports_color() -> bool:
+    return hasattr(sys.stdout, "isatty") and sys.stdout.isatty()
+
+
+class _C:
+    """ANSI escape codes."""
+
+    RESET = "\033[0m"
+    BOLD = "\033[1m"
+    DIM = "\033[2m"
+    GREEN = "\033[1;92m"
+    YELLOW = "\033[1;93m"
+    RED = "\033[1;91m"
+    CYAN = "\033[1;96m"
+    WHITE = "\033[1;97m"
+    GRAY = "\033[2;37m"
+
+
+@dataclass
+class StateConfig:
+    """One named rollout state.
+
+    ``key`` must match the string passed to ``RolloutStatusDisplay.show_state()``.
+    """
+
+    key: str
+    emoji: str
+    label: str
+    description: str
+    color: str = _C.WHITE
+
+
+@dataclass
+class ControlConfig:
+    """One keyboard/pedal binding shown in the startup banner."""
+
+    key: str
+    description: str
+
+
+# ---------------------------------------------------------------------------
+# Base display class
+# ---------------------------------------------------------------------------
+
+
+class RolloutStatusDisplay:
+    """Unified console status display.  Subclass once per strategy."""
+
+    def __init__(
+        self,
+        strategy: str,
+        states: list[StateConfig],
+        controls: list[ControlConfig],
+        info: list[str] | None = None,
+    ) -> None:
+        self.strategy = strategy
+        self._states = {s.key: s for s in states}
+        self._controls = controls
+        self._info = info or []
+        self._use_color = _supports_color()
+
+    def _c(self, code: str, text: str) -> str:
+        if not self._use_color:
+            return text
+        return f"{code}{text}{_C.RESET}"
+
+    def show_banner(self) -> None:
+        """Print startup banner: strategy name, states, controls, config info."""
+        width = 62
+        sep = self._c(_C.BOLD, "═" * width)
+
+        print(f"\n{sep}")
+        print(self._c(_C.BOLD, f"  lerobot-rollout  │  {self.strategy}"))
+
+        if self._states:
+            print()
+            for state in self._states.values():
+                label = self._c(state.color, f"{state.label:<14}")
+                desc = self._c(_C.GRAY, state.description)
+                print(f"  {state.emoji}  {label}  {desc}")
+
+        if self._controls:
+            print()
+            key_width = max(len(c.key) for c in self._controls)
+            for ctrl in self._controls:
+                key_str = self._c(_C.CYAN, f"[{ctrl.key:<{key_width}}]")
+                print(f"  {key_str}  {ctrl.description}")
+
+        if self._info:
+            print()
+            for item in self._info:
+                print(f"  {item}")
+
+        print(f"{sep}\n")
+
+    def show_state(self, state_key: str | enum.Enum) -> None:
+        """Print the current state and available controls - call this on every transition."""
+        key = state_key.value if isinstance(state_key, enum.Enum) else state_key
+        state = self._states.get(key)
+        if state is None:
+            return
+        label = self._c(state.color, f"{state.label:<14}")
+        desc = self._c(_C.GRAY, state.description)
+        print(f"\n  {state.emoji}  {label}  {desc}\n")
+
+        if self._controls:
+            key_width = max(len(c.key) for c in self._controls)
+            for ctrl in self._controls:
+                key_str = self._c(_C.CYAN, f"[{ctrl.key:<{key_width}}]")
+                print(f"  {key_str}  {ctrl.description}")
+            print()
+
+
+# ---------------------------------------------------------------------------
+# One display subclass per strategy
+# ---------------------------------------------------------------------------
+
+
+class BaseDisplay(RolloutStatusDisplay):
+    """Status display for the base (eval-only, no recording) strategy."""
+
+    _STATES = [StateConfig("running", "🟢", "RUNNING", "autonomous rollout — no recording", _C.GREEN)]
+    _CONTROLS = [ControlConfig("Ctrl+C", "stop session")]
+
+    def __init__(self, duration: float = 0) -> None:
+        info = ["No recording — evaluation only."]
+        if duration > 0:
+            info.append(f"Duration: {duration:.0f}s")
+        super().__init__("base", self._STATES, self._CONTROLS, info)
+
+
+class SentryDisplay(RolloutStatusDisplay):
+    """Status display for the sentry (continuous autonomous recording) strategy."""
+
+    _STATES = [StateConfig("recording", "🟢", "RECORDING", "continuous autonomous recording", _C.GREEN)]
+    _CONTROLS = [ControlConfig("Ctrl+C", "stop session")]
+
+    def __init__(self, episode_duration_s: float, upload_every_n_episodes: int) -> None:
+        info = [
+            f"Episode rotation: ~{episode_duration_s:.0f}s  |  "
+            f"Upload every {upload_every_n_episodes} episodes",
+        ]
+        super().__init__("sentry", self._STATES, self._CONTROLS, info)
+
+
+class HighlightDisplay(RolloutStatusDisplay):
+    """Status display for the highlight (ring-buffer on-demand save) strategy."""
+
+    def __init__(self, ring_buffer_seconds: float, save_key: str, push_key: str) -> None:
+        states = [
+            StateConfig(
+                "buffering",
+                "⚪",
+                "BUFFERING",
+                f"ring buffer active — last {ring_buffer_seconds:.0f}s captured",
+                _C.WHITE,
+            ),
+            StateConfig("recording", "🔴", "RECORDING", "live recording — press [s] to save episode", _C.RED),
+        ]
+        controls = [
+            ControlConfig(save_key, "BUFFERING ↔ RECORDING  start recording / save episode"),
+            ControlConfig(push_key, "push dataset to Hub (background)"),
+            ControlConfig("ESC", "stop session"),
+        ]
+        super().__init__("highlight", states, controls)
+
+
+class DAggerDisplay(RolloutStatusDisplay):
+    """Status display for the dagger (human-in-the-loop) strategy."""
+
+    _PAUSED_STATE = StateConfig("paused", "🟡", "PAUSED", "holding last position — awaiting input", _C.YELLOW)
+    _CORRECTING_STATE = StateConfig(
+        "correcting", "🔴", "CORRECTING", "human teleop active — recording correction", _C.RED
+    )
+
+    def __init__(
+        self,
+        record_autonomous: bool,
+        num_episodes: int,
+        episode_duration_s: float,
+        input_device: str,
+        pause_key: str,
+        correction_key: str,
+        upload_key: str,
+    ) -> None:
+        mode = "continuous recording" if record_autonomous else "corrections only"
+        auto_desc = "policy running — recording" if record_autonomous else "policy running — no recording"
+        states = [
+            StateConfig("autonomous", "🟢", "AUTONOMOUS", auto_desc, _C.GREEN),
+            self._PAUSED_STATE,
+            self._CORRECTING_STATE,
+        ]
+        controls = [
+            ControlConfig(pause_key, "AUTONOMOUS ↔ PAUSED    pause / resume policy"),
+            ControlConfig(correction_key, "PAUSED ↔ CORRECTING   start / stop correction"),
+            ControlConfig(upload_key, "push dataset to Hub"),
+            ControlConfig("ESC", "stop session"),
+        ]
+        info = [f"Target: {num_episodes} episodes  |  Input: {input_device}"]
+        if record_autonomous:
+            info.append(f"Episode rotation: ~{episode_duration_s:.0f}s")
+        super().__init__(f"dagger  [{mode}]", states, controls, info)
+
+
+if __name__ == "__main__":
+    dagger_display = DAggerDisplay(
+        record_autonomous=False,
+        num_episodes=20,
+        episode_duration_s=30,
+        input_device="keyboard",
+        pause_key="SPACE",
+        correction_key="TAB",
+        upload_key="ENTER",
+    )
+    dagger_display.show_banner()
+    dagger_display.show_state("paused")
+    dagger_display.show_state("correcting")
+    dagger_display.show_state("paused")
+    dagger_display.show_state("autonomous")

src/lerobot/rollout/strategies/highlight.py

@@ -17,6 +17,7 @@
 from __future__ import annotations
 
 import contextlib
+import enum
 import logging
 import os
 import sys
@@ -36,6 +37,7 @@ from ..configs import HighlightStrategyConfig
 from ..context import RolloutContext
 from ..ring_buffer import RolloutRingBuffer
 from .core import RolloutStrategy, safe_push_to_hub, send_next_action
+from .display import HighlightDisplay
 
 PYNPUT_AVAILABLE = _pynput_available
 keyboard = None
@@ -53,6 +55,13 @@ if PYNPUT_AVAILABLE:
 logger = logging.getLogger(__name__)
 
 
+class HighlightPhase(enum.Enum):
+    """Observable phases of a Highlight session."""
+
+    BUFFERING = "buffering"  # Ring buffer accumulating frames, not recording
+    RECORDING = "recording"  # Live recording active
+
+
 class HighlightStrategy(RolloutStrategy):
     """Autonomous rollout with on-demand recording via ring buffer.
 
@@ -64,8 +73,8 @@ class HighlightStrategy(RolloutStrategy):
     3. The episode is saved and the ring buffer resumes capturing.
 
     Requires ``streaming_encoding=True`` (enforced in config validation)
-    so that ``dataset.add_frame`` is a non-blocking queue put — draining
-    900 frames stays sub-ms per frame.
+    so that ``dataset.add_frame`` is a non-blocking queue put — flushing
+    the entire ring buffer in one tick must not stall the control loop.
     """
 
     config: HighlightStrategyConfig
@@ -105,6 +114,13 @@ class HighlightStrategy(RolloutStrategy):
             self.config.save_key,
             self.config.push_key,
         )
+        self._display = HighlightDisplay(
+            ring_buffer_seconds=self.config.ring_buffer_seconds,
+            save_key=self.config.save_key,
+            push_key=self.config.push_key,
+        )
+        self._display.show_banner()
+        self._display.show_state(HighlightPhase.BUFFERING)
 
     def run(self, ctx: RolloutContext) -> None:
         """Run the autonomous loop, buffering frames and recording on demand."""
@@ -135,8 +151,7 @@ class HighlightStrategy(RolloutStrategy):
                         break
 
                     obs = robot.get_observation()
-                    obs_processed = ctx.processors.robot_observation_processor(obs)
-                    engine.notify_observation(obs_processed)
+                    obs_processed = self._process_observation_and_notify(ctx.processors, obs)
 
                     if self._handle_warmup(cfg.use_torch_compile, loop_start, control_interval):
                         continue
@@ -163,6 +178,7 @@ class HighlightStrategy(RolloutStrategy):
                                 for buffered_frame in ring.drain():
                                     dataset.add_frame(buffered_frame)
                                 self._recording_live.set()
+                                self._display.show_state(HighlightPhase.RECORDING)
                             else:
                                 dataset.add_frame(frame)
                                 with self._episode_lock:
@@ -173,6 +189,7 @@ class HighlightStrategy(RolloutStrategy):
                                     play_sounds,
                                 )
                                 self._recording_live.clear()
+                                self._display.show_state(HighlightPhase.BUFFERING)
                                 continue  # frame already consumed — skip ring.append
 
                         if self._push_requested.is_set():
@@ -189,9 +206,7 @@ class HighlightStrategy(RolloutStrategy):
                     if (sleep_t := control_interval - dt) > 0:
                         precise_sleep(sleep_t)
                     else:
-                        logger.warning(
-                            f"Record loop is running slower ({1 / dt:.1f} Hz) than the target FPS ({cfg.fps} Hz). Dataset frames might be dropped and robot control might be unstable. Common causes are: 1) Camera FPS not keeping up 2) Policy inference taking too long 3) CPU starvation"
-                        )
+                        self._warn_slow_loop(dt, control_interval, cfg.fps)
 
             finally:
                 logger.info("Highlight control loop ended")
@@ -228,7 +243,10 @@ class HighlightStrategy(RolloutStrategy):
                     logger.info("Dataset uploaded to hub")
                     log_say("Dataset uploaded to hub", play_sounds)
 
-        self._teardown_hardware(ctx.hardware)
+        self._teardown_hardware(
+            ctx.hardware,
+            return_to_initial_position=ctx.runtime.cfg.return_to_initial_position,
+        )
         logger.info("Highlight strategy teardown complete")
 
     def _setup_keyboard(self, shutdown_event: ThreadingEvent) -> None:
@@ -253,7 +271,7 @@ class HighlightStrategy(RolloutStrategy):
 
             self._listener = keyboard.Listener(on_press=on_press)
             self._listener.start()
-            logger.info("Keyboard listener started (save='%s', push='%s', ESC=stop)", save_key, push_key)
+            logger.debug("Keyboard listener started (save='%s', push='%s', ESC=stop)", save_key, push_key)
         except ImportError:
             logger.warning("pynput not available — keyboard listener disabled")
 

src/lerobot/rollout/strategies/sentry.py

@@ -32,6 +32,7 @@ from lerobot.utils.utils import log_say
 from ..configs import SentryStrategyConfig
 from ..context import RolloutContext
 from .core import RolloutStrategy, estimate_max_episode_seconds, safe_push_to_hub, send_next_action
+from .display import SentryDisplay
 
 logger = logging.getLogger(__name__)
 
@@ -79,6 +80,11 @@ class SentryStrategy(RolloutStrategy):
             self._episode_duration_s,
             self.config.upload_every_n_episodes,
         )
+        self._display = SentryDisplay(
+            episode_duration_s=self._episode_duration_s,
+            upload_every_n_episodes=self.config.upload_every_n_episodes,
+        )
+        self._display.show_banner()
 
     def run(self, ctx: RolloutContext) -> None:
         """Run the continuous recording loop with automatic episode rotation."""
@@ -111,8 +117,7 @@ class SentryStrategy(RolloutStrategy):
                         break
 
                     obs = robot.get_observation()
-                    obs_processed = ctx.processors.robot_observation_processor(obs)
-                    engine.notify_observation(obs_processed)
+                    obs_processed = self._process_observation_and_notify(ctx.processors, obs)
 
                     if self._handle_warmup(cfg.use_torch_compile, loop_start, control_interval):
                         continue
@@ -161,9 +166,7 @@ class SentryStrategy(RolloutStrategy):
                     if (sleep_t := control_interval - dt) > 0:
                         precise_sleep(sleep_t)
                     else:
-                        logger.warning(
-                            f"Record loop is running slower ({1 / dt:.1f} Hz) than the target FPS ({cfg.fps} Hz). Dataset frames might be dropped and robot control might be unstable. Common causes are: 1) Camera FPS not keeping up 2) Policy inference taking too long 3) CPU starvation"
-                        )
+                        self._warn_slow_loop(dt, control_interval, cfg.fps)
 
             finally:
                 logger.info("Sentry control loop ended — saving final episode")
@@ -197,7 +200,10 @@ class SentryStrategy(RolloutStrategy):
                     logger.info("Dataset uploaded to hub")
                     log_say("Dataset uploaded to hub", play_sounds)
 
-        self._teardown_hardware(ctx.hardware)
+        self._teardown_hardware(
+            ctx.hardware,
+            return_to_initial_position=ctx.runtime.cfg.return_to_initial_position,
+        )
         logger.info("Sentry strategy teardown complete")
 
     def _background_push(self, dataset, cfg) -> None:

src/lerobot/scripts/convert_dataset_v21_to_v30.py

@@ -70,6 +70,7 @@ from lerobot.datasets.io_utils import (
     get_parquet_file_size_in_mb,
     get_parquet_num_frames,
     load_info,
+    load_json,
     write_episodes,
     write_info,
     write_stats,
@@ -81,9 +82,11 @@ from lerobot.datasets.utils import (
     DEFAULT_DATA_PATH,
     DEFAULT_VIDEO_FILE_SIZE_IN_MB,
     DEFAULT_VIDEO_PATH,
+    INFO_PATH,
     LEGACY_EPISODES_PATH,
     LEGACY_EPISODES_STATS_PATH,
     LEGACY_TASKS_PATH,
+    DatasetInfo,
     update_chunk_file_indices,
 )
 from lerobot.datasets.video_utils import concatenate_video_files, get_video_duration_in_s
@@ -165,7 +168,7 @@ def legacy_load_tasks(local_dir: Path) -> tuple[dict, dict]:
 def validate_local_dataset_version(local_path: Path) -> None:
     """Validate that the local dataset has the expected v2.1 version."""
     info = load_info(local_path)
-    dataset_version = info.get("codebase_version", "unknown")
+    dataset_version = info.codebase_version or "unknown"
     if dataset_version != V21:
         raise ValueError(
             f"Local dataset has codebase version '{dataset_version}', expected '{V21}'. "
@@ -256,14 +259,14 @@ def convert_data(root: Path, new_root: Path, data_file_size_in_mb: int):
 
 def get_video_keys(root):
     info = load_info(root)
-    features = info["features"]
+    features = info.features
     video_keys = [key for key, ft in features.items() if ft["dtype"] == "video"]
     return video_keys
 
 
 def get_image_keys(root):
     info = load_info(root)
-    features = info["features"]
+    features = info.features
     image_keys = [key for key, ft in features.items() if ft["dtype"] == "image"]
     return image_keys
 
@@ -434,7 +437,8 @@ def convert_episodes_metadata(root, new_root, episodes_metadata, episodes_video_
 
 
 def convert_info(root, new_root, data_file_size_in_mb, video_file_size_in_mb):
-    info = load_info(root)
+    # Load as raw dict to remove legacy v2.1 fields before constructing DatasetInfo.
+    info = load_json(root / INFO_PATH)
     info["codebase_version"] = V30
     del info["total_chunks"]
     del info["total_videos"]
@@ -449,7 +453,9 @@ def convert_info(root, new_root, data_file_size_in_mb, video_file_size_in_mb):
             # already has fps in video_info
             continue
         info["features"][key]["fps"] = info["fps"]
-    write_info(info, new_root)
+    # Convert raw dict to typed DatasetInfo before writing
+    dataset_info = DatasetInfo.from_dict(info)
+    write_info(dataset_info, new_root)
 
 
 def convert_dataset(

src/lerobot/scripts/lerobot_edit_dataset.py

@@ -150,11 +150,24 @@ Show dataset information without feature details:
         --operation.type info \
         --operation.show_features false
 
-Recompute dataset statistics:
+Recompute dataset statistics (saves to lerobot/pusht_recomputed_stats by default):
     lerobot-edit-dataset \
         --repo_id lerobot/pusht \
         --operation.type recompute_stats
 
+Recompute stats and save to a specific new repo_id:
+    lerobot-edit-dataset \
+        --repo_id lerobot/pusht \
+        --new_repo_id lerobot/pusht_new_stats \
+        --operation.type recompute_stats
+
+Recompute stats in-place (overwrites original dataset stats):
+    lerobot-edit-dataset \
+        --repo_id lerobot/pusht \
+        --new_repo_id lerobot/pusht \
+        --operation.type recompute_stats \
+        --operation.overwrite true
+
 Recompute stats for relative actions and push to hub:
     lerobot-edit-dataset \
         --repo_id lerobot/pusht \
@@ -256,6 +269,7 @@ class RecomputeStatsConfig(OperationConfig):
     relative_exclude_joints: list[str] | None = None
     chunk_size: int = 50
     num_workers: int = 0
+    overwrite: bool = False
 
 
 @OperationConfig.register_subclass("info")
@@ -280,16 +294,30 @@ class EditDatasetConfig:
     push_to_hub: bool = False
 
 
+def _resolve_io_paths(
+    repo_id: str,
+    new_repo_id: str | None,
+    root: Path | str | None,
+    new_root: Path | str | None,
+    default_new_repo_id: str | None = None,
+) -> tuple[str, Path, Path]:
+    """Resolve input/output paths and repo_id for dataset operations.
+
+    Returns (output_repo_id, input_path, output_path) with resolved (symlink-safe) paths.
+    """
+    input_path = (Path(root) if root else HF_LEROBOT_HOME / repo_id).resolve()
+    output_repo_id = new_repo_id or default_new_repo_id or repo_id
+    output_path = (Path(new_root) if new_root else HF_LEROBOT_HOME / output_repo_id).resolve()
+    return output_repo_id, input_path, output_path
+
+
 def get_output_path(
     repo_id: str,
     new_repo_id: str | None,
     root: Path | str | None,
     new_root: Path | str | None,
 ) -> tuple[str, Path]:
-    input_path = Path(root) if root else HF_LEROBOT_HOME / repo_id
-
-    output_repo_id = new_repo_id if new_repo_id else repo_id
-    output_path = Path(new_root) if new_root else HF_LEROBOT_HOME / output_repo_id
+    output_repo_id, input_path, output_path = _resolve_io_paths(repo_id, new_repo_id, root, new_root)
 
     # In case of in-place modification, create a backup of the original dataset (if it exists)
     if output_path == input_path:
@@ -557,7 +585,39 @@ def handle_recompute_stats(cfg: EditDatasetConfig) -> None:
     if not isinstance(cfg.operation, RecomputeStatsConfig):
         raise ValueError("Operation config must be RecomputeStatsConfig")
 
-    dataset = LeRobotDataset(cfg.repo_id, root=cfg.root)
+    # Determine whether this is an in-place operation
+    output_repo_id, input_root, output_root = _resolve_io_paths(
+        cfg.repo_id,
+        cfg.new_repo_id,
+        cfg.root,
+        cfg.new_root,
+        default_new_repo_id=f"{cfg.repo_id}_recomputed_stats",
+    )
+    in_place = output_root == input_root
+
+    if in_place and not cfg.operation.overwrite:
+        raise ValueError(
+            f"recompute_stats would overwrite the dataset in-place at {input_root}. "
+            "Pass --operation.overwrite true to allow in-place modification, "
+            "or use --new_repo_id / --new_root to write to a different location. "
+            f"Default output repo_id when neither is set: '{cfg.repo_id}_recomputed_stats'."
+        )
+
+    if in_place:
+        logging.warning(
+            f"Overwriting dataset stats in-place at {input_root}. The original stats will be lost."
+        )
+        dataset = LeRobotDataset(cfg.repo_id, root=input_root)
+    else:
+        logging.info(f"Copying dataset from {input_root} to {output_root}")
+        if output_root.exists():
+            backup_path = output_root.with_name(output_root.name + "_old")
+            logging.warning(f"Output directory {output_root} already exists. Moving to {backup_path}")
+            if backup_path.exists():
+                shutil.rmtree(backup_path)
+            shutil.move(output_root, backup_path)
+        shutil.copytree(input_root, output_root)
+        dataset = LeRobotDataset(output_repo_id, root=output_root)
 
     logging.info(f"Recomputing stats for {cfg.repo_id}")
     if cfg.operation.relative_action:
@@ -578,7 +638,7 @@ def handle_recompute_stats(cfg: EditDatasetConfig) -> None:
     logging.info(f"Stats written to {dataset.root}")
 
     if cfg.push_to_hub:
-        logging.info(f"Pushing to hub as {dataset.meta.repo_id}...")
+        logging.info(f"Pushing to hub as {dataset.repo_id}...")
         dataset.push_to_hub()
 
 

src/lerobot/scripts/lerobot_record.py

@@ -389,7 +389,8 @@ def record(
             sanity_check_dataset_robot_compatibility(dataset, robot, cfg.dataset.fps, dataset_features)
         else:
             # Reject eval_ prefix — for policy evaluation use lerobot-rollout
-            if cfg.dataset.repo_id.startswith("eval_"):
+            repo_name = cfg.dataset.repo_id.split("/", 1)[-1]
+            if repo_name.startswith("eval_"):
                 raise ValueError(
                     "Dataset names starting with 'eval_' are reserved for policy evaluation. "
                     "lerobot-record is for data collection only. Use lerobot-rollout for policy deployment."

src/lerobot/scripts/lerobot_train.py

@@ -47,6 +47,7 @@ from lerobot.datasets import EpisodeAwareSampler, make_dataset
 from lerobot.envs import close_envs, make_env, make_env_pre_post_processors
 from lerobot.optim.factory import make_optimizer_and_scheduler
 from lerobot.policies import PreTrainedPolicy, make_policy, make_pre_post_processors
+from lerobot.rewards import make_reward_pre_post_processors
 from lerobot.utils.import_utils import register_third_party_plugins
 from lerobot.utils.logging_utils import AverageMeter, MetricsTracker
 from lerobot.utils.random_utils import set_seed
@@ -70,8 +71,8 @@ def update_policy(
     accelerator: "Accelerator",
     lr_scheduler=None,
     lock=None,
-    rabc_weights_provider=None,
-) -> tuple[MetricsTracker, dict]:
+    sample_weighter=None,
+) -> tuple[MetricsTracker, dict | None]:
     """
     Performs a single training step to update the policy's weights.
 
@@ -87,7 +88,7 @@ def update_policy(
         accelerator: The Accelerator instance for distributed training and mixed precision.
         lr_scheduler: An optional learning rate scheduler.
         lock: An optional lock for thread-safe optimizer updates.
-        rabc_weights_provider: Optional RABCWeights instance for sample weighting.
+        sample_weighter: Optional SampleWeighter instance for per-sample loss weighting.
 
     Returns:
         A tuple containing:
@@ -97,27 +98,31 @@ def update_policy(
     start_time = time.perf_counter()
     policy.train()
 
-    # Get RA-BC weights if enabled
-    rabc_batch_weights = None
-    rabc_batch_stats = None
-    if rabc_weights_provider is not None:
-        rabc_batch_weights, rabc_batch_stats = rabc_weights_provider.compute_batch_weights(batch)
+    # Compute sample weights if a weighter is provided
+    sample_weights = None
+    weight_stats = None
+    if sample_weighter is not None:
+        sample_weights, weight_stats = sample_weighter.compute_batch_weights(batch)
 
     # Let accelerator handle mixed precision
     with accelerator.autocast():
-        # Use per-sample loss when RA-BC is enabled for proper weighting
-        if rabc_batch_weights is not None:
-            # Get per-sample losses
+        if sample_weights is not None:
+            # Use per-sample loss for weighted training
+            # Note: Policies supporting sample weighting must implement forward(batch, reduction="none")
             per_sample_loss, output_dict = policy.forward(batch, reduction="none")
 
-            # Apply RA-BC weights: L_RA-BC = Σ(w_i * l_i) / (Σw_i + ε)
-            # rabc_batch_weights is already normalized to sum to batch_size
+            # Weighted loss: each sample's contribution is scaled by its weight.
+            # We divide by weight sum (not batch size) so that if some weights are zero,
+            # the remaining samples contribute proportionally more, preserving gradient scale.
+            # Weights are pre-normalized to sum to batch_size for stable training dynamics.
             epsilon = 1e-6
-            loss = (per_sample_loss * rabc_batch_weights).sum() / (rabc_batch_weights.sum() + epsilon)
-            # Log raw mean weight (before normalization) - this is the meaningful metric
-            output_dict["rabc_mean_weight"] = rabc_batch_stats["raw_mean_weight"]
-            output_dict["rabc_num_zero_weight"] = rabc_batch_stats["num_zero_weight"]
-            output_dict["rabc_num_full_weight"] = rabc_batch_stats["num_full_weight"]
+            loss = (per_sample_loss * sample_weights).sum() / (sample_weights.sum() + epsilon)
+
+            # Log weighting statistics
+            if output_dict is None:
+                output_dict = {}
+            for key, value in weight_stats.items():
+                output_dict[f"sample_weight_{key}"] = value
         else:
             loss, output_dict = policy.forward(batch)
 
@@ -188,8 +193,8 @@ def train(cfg: TrainPipelineConfig, accelerator: "Accelerator | None" = None):
 
         ddp_kwargs = DistributedDataParallelKwargs(find_unused_parameters=True)
         # Accelerate auto-detects the device based on the available hardware and ignores the policy.device setting.
-        # Force the device to be CPU when policy.device is set to CPU.
-        force_cpu = cfg.policy.device == "cpu"
+        # Force the device to be CPU when the active config's device is set to CPU (works for both policy and reward model training).
+        force_cpu = cfg.trainable_config.device == "cpu"
         accelerator = Accelerator(
             step_scheduler_with_optimizer=False,
             kwargs_handlers=[ddp_kwargs],
@@ -245,26 +250,49 @@ def train(cfg: TrainPipelineConfig, accelerator: "Accelerator | None" = None):
         logging.info("Creating env")
         eval_env = make_env(cfg.env, n_envs=cfg.eval.batch_size, use_async_envs=cfg.eval.use_async_envs)
 
-    if is_main_process:
-        logging.info("Creating policy")
-    policy = make_policy(
-        cfg=cfg.policy,
-        ds_meta=dataset.meta,
-        rename_map=cfg.rename_map,
-    )
+    if cfg.is_reward_model_training:
+        if is_main_process:
+            logging.info("Creating reward model")
+        from lerobot.rewards import make_reward_model
+
+        policy = make_reward_model(
+            cfg=cfg.reward_model,
+            dataset_stats=dataset.meta.stats,
+            dataset_meta=dataset.meta,
+        )
+        if not policy.is_trainable:
+            raise ValueError(
+                f"Reward model '{policy.name}' is zero-shot and cannot be trained via lerobot-train. "
+                "Use it directly for inference via compute_reward() (e.g. offline precompute)."
+            )
+    else:
+        if is_main_process:
+            logging.info("Creating policy")
+        policy = make_policy(
+            cfg=cfg.policy,
+            ds_meta=dataset.meta,
+            rename_map=cfg.rename_map,
+        )
 
     if cfg.peft is not None:
-        logging.info("Using PEFT! Wrapping model.")
-        # Convert CLI peft config to dict for overrides
-        peft_cli_overrides = dataclasses.asdict(cfg.peft)
-        policy = policy.wrap_with_peft(peft_cli_overrides=peft_cli_overrides)
+        if cfg.is_reward_model_training:
+            raise ValueError("PEFT is only supported for policy training. ")
+        from peft import PeftModel
 
-    # Wait for all processes to finish policy creation before continuing
+        if isinstance(policy, PeftModel):
+            logging.info("PEFT adapter already loaded from checkpoint, skipping wrap_with_peft.")
+        else:
+            logging.info("Using PEFT! Wrapping model.")
+            peft_cli_overrides = dataclasses.asdict(cfg.peft)
+            policy = policy.wrap_with_peft(peft_cli_overrides=peft_cli_overrides)
+
+    # Wait for all processes to finish model creation before continuing
     accelerator.wait_for_everyone()
 
-    processor_pretrained_path = cfg.policy.pretrained_path
+    active_cfg = cfg.trainable_config
+    processor_pretrained_path = active_cfg.pretrained_path
     if (
-        getattr(cfg.policy, "use_relative_actions", False)
+        getattr(active_cfg, "use_relative_actions", False)
         and processor_pretrained_path is not None
         and not cfg.resume
     ):
@@ -274,18 +302,15 @@ def train(cfg: TrainPipelineConfig, accelerator: "Accelerator | None" = None):
         )
         processor_pretrained_path = None
 
-    # Create processors - only provide dataset_stats if not resuming from saved processors
     processor_kwargs = {}
     postprocessor_kwargs = {}
     if (processor_pretrained_path and not cfg.resume) or not processor_pretrained_path:
-        # Only provide dataset_stats when not resuming from saved processor state
         processor_kwargs["dataset_stats"] = dataset.meta.stats
 
-    # For SARM, always provide dataset_meta for progress normalization
-    if cfg.policy.type == "sarm":
+    if cfg.is_reward_model_training:
         processor_kwargs["dataset_meta"] = dataset.meta
 
-    if processor_pretrained_path is not None:
+    if not cfg.is_reward_model_training and processor_pretrained_path is not None:
         processor_kwargs["preprocessor_overrides"] = {
             "device_processor": {"device": device.type},
             "normalizer_processor": {
@@ -305,38 +330,36 @@ def train(cfg: TrainPipelineConfig, accelerator: "Accelerator | None" = None):
             },
         }
 
-    preprocessor, postprocessor = make_pre_post_processors(
-        policy_cfg=cfg.policy,
-        pretrained_path=processor_pretrained_path,
-        **processor_kwargs,
-        **postprocessor_kwargs,
-    )
+    if cfg.is_reward_model_training:
+        preprocessor, postprocessor = make_reward_pre_post_processors(
+            cfg.reward_model,
+            **processor_kwargs,
+        )
+    else:
+        preprocessor, postprocessor = make_pre_post_processors(
+            policy_cfg=cfg.policy,
+            pretrained_path=processor_pretrained_path,
+            **processor_kwargs,
+            **postprocessor_kwargs,
+        )
 
     if is_main_process:
         logging.info("Creating optimizer and scheduler")
     optimizer, lr_scheduler = make_optimizer_and_scheduler(cfg, policy)
 
-    # Load precomputed SARM progress for RA-BC if enabled
-    # Generate progress using: src/lerobot/policies/sarm/compute_rabc_weights.py
-    rabc_weights = None
-    if cfg.use_rabc:
-        from lerobot.utils.rabc import RABCWeights
+    # Create sample weighter if configured (e.g., for RA-BC training)
+    sample_weighter = None
+    if cfg.sample_weighting is not None:
+        from lerobot.utils.sample_weighting import make_sample_weighter
 
-        # Get chunk_size from policy config
-        chunk_size = getattr(policy.config, "chunk_size", None)
-        if chunk_size is None:
-            raise ValueError("Chunk size is not found in policy config")
-
-        head_mode = getattr(cfg, "rabc_head_mode", "sparse")
-        logging.info(f"Loading SARM progress for RA-BC from {cfg.rabc_progress_path}")
-        logging.info(f"Using chunk_size={chunk_size} from policy config, head_mode={head_mode}")
-        rabc_weights = RABCWeights(
-            progress_path=cfg.rabc_progress_path,
-            chunk_size=chunk_size,
-            head_mode=head_mode,
-            kappa=getattr(cfg, "rabc_kappa", 0.01),
-            epsilon=getattr(cfg, "rabc_epsilon", 1e-6),
-            device=device,
+        if is_main_process:
+            logging.info(f"Creating sample weighter: {cfg.sample_weighting.type}")
+        sample_weighter = make_sample_weighter(
+            cfg.sample_weighting,
+            policy,
+            device,
+            dataset_root=cfg.dataset.root,
+            dataset_repo_id=cfg.dataset.repo_id,
         )
 
     step = 0  # number of policy updates (forward + backward + optim)
@@ -365,13 +388,13 @@ def train(cfg: TrainPipelineConfig, accelerator: "Accelerator | None" = None):
         logging.info(f"{num_total_params=} ({format_big_number(num_total_params)})")
 
     # create dataloader for offline training
-    if hasattr(cfg.policy, "drop_n_last_frames"):
+    if hasattr(active_cfg, "drop_n_last_frames"):
         shuffle = False
         sampler = EpisodeAwareSampler(
             dataset.meta.episodes["dataset_from_index"],
             dataset.meta.episodes["dataset_to_index"],
             episode_indices_to_use=dataset.episodes,
-            drop_n_last_frames=cfg.policy.drop_n_last_frames,
+            drop_n_last_frames=active_cfg.drop_n_last_frames,
             shuffle=True,
         )
     else:
@@ -448,7 +471,7 @@ def train(cfg: TrainPipelineConfig, accelerator: "Accelerator | None" = None):
             cfg.optimizer.grad_clip_norm,
             accelerator=accelerator,
             lr_scheduler=lr_scheduler,
-            rabc_weights_provider=rabc_weights,
+            sample_weighter=sample_weighter,
         )
 
         # Note: eval and checkpoint happens *after* the `step`th training update has completed, so we
@@ -467,16 +490,10 @@ def train(cfg: TrainPipelineConfig, accelerator: "Accelerator | None" = None):
                 wandb_log_dict = train_tracker.to_dict()
                 if output_dict:
                     wandb_log_dict.update(output_dict)
-                # Log RA-BC statistics if enabled
-                if rabc_weights is not None:
-                    rabc_stats = rabc_weights.get_stats()
-                    wandb_log_dict.update(
-                        {
-                            "rabc_delta_mean": rabc_stats["delta_mean"],
-                            "rabc_delta_std": rabc_stats["delta_std"],
-                            "rabc_num_frames": rabc_stats["num_frames"],
-                        }
-                    )
+                # Log sample weighting statistics if enabled
+                if sample_weighter is not None:
+                    weighter_stats = sample_weighter.get_stats()
+                    wandb_log_dict.update({f"sample_weighting/{k}": v for k, v in weighter_stats.items()})
                 wandb_logger.log_dict(wandb_log_dict, step)
             train_tracker.reset_averages()
 
@@ -558,14 +575,15 @@ def train(cfg: TrainPipelineConfig, accelerator: "Accelerator | None" = None):
     if is_main_process:
         logging.info("End of training")
 
-        if cfg.policy.push_to_hub:
-            unwrapped_policy = accelerator.unwrap_model(policy)
-            if cfg.policy.use_peft:
-                unwrapped_policy.push_model_to_hub(cfg, peft_model=unwrapped_policy)
+        if getattr(active_cfg, "push_to_hub", False):
+            unwrapped_model = accelerator.unwrap_model(policy)
+            # PEFT only applies when training a policy — reward models use the plain path.
+            if not cfg.is_reward_model_training and cfg.policy.use_peft:
+                unwrapped_model.push_model_to_hub(cfg, peft_model=unwrapped_model)
             else:
-                unwrapped_policy.push_model_to_hub(cfg)
-            preprocessor.push_to_hub(cfg.policy.repo_id)
-            postprocessor.push_to_hub(cfg.policy.repo_id)
+                unwrapped_model.push_model_to_hub(cfg)
+            preprocessor.push_to_hub(active_cfg.repo_id)
+            postprocessor.push_to_hub(active_cfg.repo_id)
 
     # Properly clean up the distributed process group
     accelerator.wait_for_everyone()

src/lerobot/teleoperators/bi_openarm_leader/bi_openarm_leader.py

@@ -49,6 +49,7 @@ class BiOpenArmLeader(Teleoperator):
             can_data_bitrate=config.left_arm_config.can_data_bitrate,
             motor_config=config.left_arm_config.motor_config,
             manual_control=config.left_arm_config.manual_control,
+            use_velocity_and_torque=config.left_arm_config.use_velocity_and_torque,
             position_kd=config.left_arm_config.position_kd,
             position_kp=config.left_arm_config.position_kp,
         )
@@ -63,6 +64,7 @@ class BiOpenArmLeader(Teleoperator):
             can_data_bitrate=config.right_arm_config.can_data_bitrate,
             motor_config=config.right_arm_config.motor_config,
             manual_control=config.right_arm_config.manual_control,
+            use_velocity_and_torque=config.right_arm_config.use_velocity_and_torque,
             position_kd=config.right_arm_config.position_kd,
             position_kp=config.right_arm_config.position_kp,
         )

src/lerobot/teleoperators/openarm_leader/config_openarm_leader.py

@@ -60,6 +60,10 @@ class OpenArmLeaderConfigBase:
     # When enabled, motors have torque disabled for manual movement
     manual_control: bool = True
 
+    # When True, expose `.vel` and `.torque` per motor in action features.
+    # Default False for compatibility with the position-only openarm_mini teleoperator.
+    use_velocity_and_torque: bool = False
+
     # TODO(Steven, Pepijn): Not used ... ?
     # MIT control parameters (used when manual_control=False for torque control)
     # List of 8 values: [joint_1, joint_2, joint_3, joint_4, joint_5, joint_6, joint_7, gripper]

src/lerobot/teleoperators/openarm_leader/openarm_leader.py

@@ -70,8 +70,9 @@ class OpenArmLeader(Teleoperator):
         features: dict[str, type] = {}
         for motor in self.bus.motors:
             features[f"{motor}.pos"] = float
-            features[f"{motor}.vel"] = float
-            features[f"{motor}.torque"] = float
+            if self.config.use_velocity_and_torque:
+                features[f"{motor}.vel"] = float
+                features[f"{motor}.torque"] = float
         return features
 
     @property
@@ -201,8 +202,9 @@ class OpenArmLeader(Teleoperator):
         for motor in self.bus.motors:
             state = states.get(motor, {})
             action_dict[f"{motor}.pos"] = state.get("position")
-            action_dict[f"{motor}.vel"] = state.get("velocity")
-            action_dict[f"{motor}.torque"] = state.get("torque")
+            if self.config.use_velocity_and_torque:
+                action_dict[f"{motor}.vel"] = state.get("velocity")
+                action_dict[f"{motor}.torque"] = state.get("torque")
 
         dt_ms = (time.perf_counter() - start) * 1e3
         logger.debug(f"{self} read state: {dt_ms:.1f}ms")

src/lerobot/teleoperators/openarm_mini/openarm_mini.py

@@ -112,7 +112,7 @@ class OpenArmMini(Teleoperator):
 
     @property
     def feedback_features(self) -> dict[str, type]:
-        return {}
+        return self.action_features
 
     @property
     def is_connected(self) -> bool:
@@ -348,8 +348,9 @@ class OpenArmMini(Teleoperator):
         if left_goals:
             self.bus_left.sync_write("Goal_Position", left_goals)
 
+    @check_if_not_connected
     def send_feedback(self, feedback: dict[str, float]) -> None:
-        raise NotImplementedError("Feedback is not yet implemented for OpenArm Mini.")
+        self.write_goal_positions(feedback)
 
     @check_if_not_connected
     def disconnect(self) -> None:

src/lerobot/teleoperators/so_leader/so_leader.py

@@ -59,7 +59,7 @@ class SOLeader(Teleoperator):
 
     @property
     def feedback_features(self) -> dict[str, type]:
-        return {}
+        return self.action_features
 
     @property
     def is_connected(self) -> bool:
@@ -130,6 +130,12 @@ class SOLeader(Teleoperator):
         for motor in self.bus.motors:
             self.bus.write("Operating_Mode", motor, OperatingMode.POSITION.value)
 
+    def enable_torque(self) -> None:
+        self.bus.enable_torque()
+
+    def disable_torque(self) -> None:
+        self.bus.disable_torque()
+
     def setup_motors(self) -> None:
         for motor in reversed(self.bus.motors):
             input(f"Connect the controller board to the '{motor}' motor only and press enter.")
@@ -145,9 +151,11 @@ class SOLeader(Teleoperator):
         logger.debug(f"{self} read action: {dt_ms:.1f}ms")
         return action
 
+    @check_if_not_connected
     def send_feedback(self, feedback: dict[str, float]) -> None:
-        # TODO: Implement force feedback
-        raise NotImplementedError
+        goals = {k.removesuffix(".pos"): v for k, v in feedback.items() if k.endswith(".pos")}
+        if goals:
+            self.bus.sync_write("Goal_Position", goals)
 
     @check_if_not_connected
     def disconnect(self) -> None:

src/lerobot/templates/lerobot_rewardmodel_modelcard_template.md

@@ -0,0 +1,55 @@
+---
+# For reference on model card metadata, see the spec: https://github.com/huggingface/hub-docs/blob/main/modelcard.md?plain=1
+# Doc / guide: https://huggingface.co/docs/hub/model-cards
+# prettier-ignore
+{{card_data}}
+---
+
+# Reward Model Card for {{ model_name | default("Reward Model ID", true) }}
+
+<!-- Provide a quick summary of what the reward model is/does. -->
+
+{% if model_name == "reward_classifier" %}
+A reward classifier is a lightweight neural network that scores observations or trajectories for task success, providing a learned reward signal or offline evaluation when explicit rewards are unavailable.
+{% elif model_name == "sarm" %}
+A Success-Aware Reward Model (SARM) predicts a dense reward signal from observations, typically used downstream for reinforcement learning or human-in-the-loop fine-tuning when task success is not directly observable.
+{% else %}
+_Reward model type not recognized — please update this template._
+{% endif %}
+
+This reward model has been trained and pushed to the Hub using [LeRobot](https://github.com/huggingface/lerobot).
+See the full documentation at [LeRobot Docs](https://huggingface.co/docs/lerobot/index).
+
+---
+
+## How to Get Started with the Reward Model
+
+### Train from scratch
+
+```bash
+lerobot-train \
+  --dataset.repo_id=${HF_USER}/<dataset> \
+  --reward_model.type={{ model_name | default("reward_classifier", true) }} \
+  --output_dir=outputs/train/<desired_reward_model_repo_id> \
+  --job_name=lerobot_reward_training \
+  --reward_model.device=cuda \
+  --reward_model.repo_id=${HF_USER}/<desired_reward_model_repo_id> \
+  --wandb.enable=true
+```
+
+_Writes checkpoints to `outputs/train/<desired_reward_model_repo_id>/checkpoints/`._
+
+### Load the reward model in Python
+
+```python
+from lerobot.rewards import make_reward_model
+
+reward_model = make_reward_model(pretrained_path="<hf_user>/<reward_model_repo_id>")
+reward = reward_model.compute_reward(batch)
+```
+
+---
+
+## Model Details
+
+- **License:** {{ license | default("\[More Information Needed]", true) }}

src/lerobot/utils/import_utils.py

@@ -115,7 +115,9 @@ _feetech_sdk_available = is_package_available("feetech-servo-sdk", import_name="
 _reachy2_sdk_available = is_package_available("reachy2_sdk")
 _can_available = is_package_available("python-can", "can")
 _unitree_sdk_available = is_package_available("unitree-sdk2py", "unitree_sdk2py")
-_pyrealsense2_available = is_package_available("pyrealsense2")
+_pyrealsense2_available = is_package_available("pyrealsense2") or is_package_available(
+    "pyrealsense2-macosx", import_name="pyrealsense2"
+)
 _zmq_available = is_package_available("pyzmq", import_name="zmq")
 _hebi_available = is_package_available("hebi-py", import_name="hebi")
 _teleop_available = is_package_available("teleop")

src/lerobot/utils/sample_weighting.py

@@ -0,0 +1,239 @@
+# Copyright 2025 The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Sample weighting abstraction for training.
+
+This module provides an abstract base class for sample weighting strategies (e.g., RA-BC)
+that can be used during training without polluting the training script with
+policy-specific code.
+
+Example usage:
+    # In training config
+    sample_weighting:
+        type: rabc
+        progress_path: hf://datasets/my-dataset/sarm_progress.parquet
+        head_mode: sparse
+        kappa: 0.01
+
+    # In training script
+    sample_weighter = make_sample_weighter(cfg.sample_weighting, policy, device, dataset_root=cfg.dataset.root, dataset_repo_id=cfg.dataset.repo_id)
+    ...
+    weights, stats = sample_weighter.compute_batch_weights(batch)
+"""
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+from dataclasses import dataclass, field
+from pathlib import Path
+from typing import TYPE_CHECKING
+
+import torch
+
+if TYPE_CHECKING:
+    from lerobot.policies.pretrained import PreTrainedPolicy
+
+
+class SampleWeighter(ABC):
+    """
+    Implementations compute per-sample weights that can be used to weight
+    the loss during training. This enables techniques like:
+    - RA-BC (Reward-Aligned Behavior Cloning)
+    - Importance sampling
+    - Curriculum learning
+    - Quality-based filtering
+    """
+
+    @abstractmethod
+    def compute_batch_weights(self, batch: dict) -> tuple[torch.Tensor, dict]:
+        """
+        Compute per-sample weights for a training batch.
+
+        Args:
+            batch: Training batch dictionary containing at minimum an "index" key
+                   with global frame indices.
+        """
+
+    @abstractmethod
+    def get_stats(self) -> dict:
+        """
+        Get global statistics about the weighting strategy.
+        """
+
+
+@dataclass
+class SampleWeightingConfig:
+    """
+    Configuration for sample weighting during training.
+
+    This is a generic config that supports multiple weighting strategies.
+    The `type` field determines which implementation to use, and `extra_params`
+    contains additional type-specific parameters.
+
+    Attributes:
+        type: Weighting strategy type ("rabc", "uniform", etc.)
+        progress_path: Path to precomputed progress values (for RABC)
+        head_mode: Which model head to use for progress ("sparse" or "dense")
+        kappa: Hard threshold for high-quality samples (RABC-specific)
+        epsilon: Small constant for numerical stability
+        extra_params: Additional type-specific parameters passed to the weighter
+    """
+
+    type: str = "rabc"
+    progress_path: str | None = None
+    head_mode: str = "sparse"
+    kappa: float = 0.01
+    epsilon: float = 1e-6
+    # Additional type-specific params can be added here or passed via extra_params
+    extra_params: dict = field(default_factory=dict)
+
+
+def make_sample_weighter(
+    config: SampleWeightingConfig | None,
+    policy: PreTrainedPolicy,
+    device: torch.device,
+    dataset_root: str | None = None,
+    dataset_repo_id: str | None = None,
+) -> SampleWeighter | None:
+    """
+    Factory function to create a SampleWeighter from config.
+
+    This keeps policy-specific initialization logic out of the training script.
+
+    Args:
+        config: Sample weighting configuration, or None to disable weighting.
+        policy: The policy being trained (used to extract chunk_size, etc.)
+        device: Device to place weight tensors on.
+        dataset_root: Local path to dataset root (for auto-detecting progress_path).
+        dataset_repo_id: HuggingFace repo ID (for auto-detecting progress_path).
+    """
+    if config is None:
+        return None
+
+    if config.type == "rabc":
+        return _make_rabc_weighter(config, policy, device, dataset_root, dataset_repo_id)
+
+    if config.type == "uniform":
+        # No-op weighter that returns uniform weights
+        return UniformWeighter(device=device)
+
+    raise ValueError(f"Unknown sample weighting type: '{config.type}'. Supported types: 'rabc', 'uniform'")
+
+
+def _make_rabc_weighter(
+    config: SampleWeightingConfig,
+    policy: PreTrainedPolicy,
+    device: torch.device,
+    dataset_root: str | None = None,
+    dataset_repo_id: str | None = None,
+) -> SampleWeighter:
+    """Create RABC weighter with policy-specific initialization.
+
+    Args:
+        config: Sample weighting configuration.
+        policy: The policy being trained (used to extract chunk_size).
+        device: Device to place weight tensors on.
+        dataset_root: Local path to dataset root (for auto-detecting progress_path).
+        dataset_repo_id: HuggingFace repo ID (for auto-detecting progress_path).
+    """
+    # Import here to avoid circular imports and keep RABC code in SARM module
+    from lerobot.rewards.sarm.rabc import RABCWeights
+
+    # Extract chunk_size from policy config
+    chunk_size = getattr(policy.config, "chunk_size", None)
+    if chunk_size is None:
+        raise ValueError(
+            "RABC sample weighting requires a policy with 'chunk_size' in its config. "
+            "This is typically set for action-chunking policies like ACT, Diffusion, PI0, etc."
+        )
+
+    # Determine progress_path: use explicit config or auto-detect from dataset
+    progress_path = config.progress_path
+    if progress_path is None:
+        if dataset_root:
+            progress_path = str(Path(dataset_root) / "sarm_progress.parquet")
+        elif dataset_repo_id:
+            progress_path = f"hf://datasets/{dataset_repo_id}/sarm_progress.parquet"
+        else:
+            raise ValueError(
+                "RABC sample weighting requires 'progress_path' to be set, "
+                "or dataset_root/dataset_repo_id for auto-detection. "
+                "Generate progress values using: "
+                "python -m lerobot.rewards.sarm.compute_rabc_weights --help"
+            )
+
+    return RABCWeights(
+        progress_path=progress_path,
+        chunk_size=chunk_size,
+        head_mode=config.head_mode,
+        kappa=config.kappa,
+        epsilon=config.epsilon,
+        device=device,
+        **config.extra_params,
+    )
+
+
+class UniformWeighter(SampleWeighter):
+    """
+    No-op sample weighter that returns uniform weights.
+
+    Useful as a baseline or when you want to disable weighting without
+    changing the training code structure.
+
+    Note:
+        Batch size is determined by looking for tensor values in the batch
+        dictionary. The method checks common keys like "action", "index",
+        and "observation.state" first, then falls back to scanning all values.
+    """
+
+    def __init__(self, device: torch.device):
+        self.device = device
+
+    def compute_batch_weights(self, batch: dict) -> tuple[torch.Tensor, dict]:
+        """Return uniform weights (all ones)."""
+        batch_size = self._determine_batch_size(batch)
+
+        weights = torch.ones(batch_size, device=self.device)
+        stats = {"mean_weight": 1.0, "type": "uniform"}
+        return weights, stats
+
+    def _determine_batch_size(self, batch: dict) -> int:
+        """
+        Determine batch size from the batch dictionary.
+
+        Checks common keys first, then scans all values for tensors.
+
+        Args:
+            batch: Training batch dictionary.
+        """
+        if not batch:
+            raise ValueError("Cannot determine batch size from empty batch")
+
+        # Check common keys first
+        for key in ["action", "index", "observation.state"]:
+            if key in batch and isinstance(batch[key], torch.Tensor):
+                return batch[key].shape[0]
+
+        # Scan all values for any tensor
+        for value in batch.values():
+            if isinstance(value, torch.Tensor) and value.ndim >= 1:
+                return value.shape[0]
+
+        # Last resort: return 1 (this handles non-tensor batches)
+        return 1
+
+    def get_stats(self) -> dict:
+        """Return empty stats for uniform weighting."""
+        return {"type": "uniform"}

tests/artifacts/policies/aloha_sim_insertion_human_act_1000_steps/actions.safetensors

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:c2b8f8532c7a0b776de5e536b8b54e30b1a0c2e3d5cc25a2d86fe43e40ae5e8c
+oid sha256:8a31653c11eccdd4d80fd3f6a351cd54c49b8a48db1f7e9faf38fddd7900a09f
 size 515400

tests/artifacts/policies/aloha_sim_insertion_human_act_1000_steps/grad_stats.safetensors

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:224b5fa4828aa88171b68c036e8919c1eae563e2113f03b6461eadf5bf8525a6
+oid sha256:75bf051698b37dcd7517ec8025a896ab5a0551a6dde5f89d0a3d5d50966e83e6
 size 31672

tests/artifacts/policies/aloha_sim_insertion_human_act_1000_steps/output_dict.safetensors

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:016d2fa8fe5f58017dfd46f4632fdc19dfd751e32a2c7cde2077c6f95546d6bd
+oid sha256:88e10930a10041d50f2cf369e6813ac14618d13dad1c21bdde1ac7798611c6ba
 size 68

tests/artifacts/policies/aloha_sim_insertion_human_act_1000_steps/param_stats.safetensors

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:eca0d87a699620e4fec7e68539b0be91e4cc933f6bf12032da52c182ab6f38cf
+oid sha256:89833a5ccdb7d85c83f717ff8ec68b8e822005cb8803899acaae88c578e2e3ae
 size 31672

tests/datasets/test_aggregate.py

@@ -113,7 +113,7 @@ def assert_metadata_consistency(aggr_ds, ds_0, ds_1):
     """Test that metadata is correctly aggregated."""
     # Test basic info
     assert aggr_ds.fps == ds_0.fps == ds_1.fps, "FPS should be the same across all datasets"
-    assert aggr_ds.meta.info["robot_type"] == ds_0.meta.info["robot_type"] == ds_1.meta.info["robot_type"], (
+    assert aggr_ds.meta.info.robot_type == ds_0.meta.info.robot_type == ds_1.meta.info.robot_type, (
         "Robot type should be the same"
     )
 
@@ -153,8 +153,8 @@ def assert_video_frames_integrity(aggr_ds, ds_0, ds_1):
 
     video_keys = list(
         filter(
-            lambda key: aggr_ds.meta.info["features"][key]["dtype"] == "video",
-            aggr_ds.meta.info["features"].keys(),
+            lambda key: aggr_ds.meta.info.features[key]["dtype"] == "video",
+            aggr_ds.meta.info.features.keys(),
         )
     )