Files
lerobot/examples/umi_pi0_relative_ee/evaluate.py
T
Pepijn 8455efc474 feat(umi): simplify to derive_state_from_action and cam0-only
- Remove fix_dataset.py (user fixes dataset at source)
- evaluate.py: replace observation.pose/joints with observation.state
  (8D, derived from action during training, from FK at inference)
- evaluate.py: remove cam1 — training uses only cam0
- docs: rewrite workflow around derive_state_from_action=true,
  updated recompute-stats and training commands with
  relative_exclude_joints for gripper dims

Made-with: Cursor
2026-04-02 15:02:20 +02:00

298 lines
10 KiB
Python

#!/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.
"""
Inference script for a pi0 model trained with UMI-style relative EE actions
on an OpenArm robot (single right arm, one wrist camera).
Training dataset layout:
observation.images.cam0 [3, 720, 960]
action [x, y, z, ax, ay, az, proximal, distal] (shape 8)
The model uses ``derive_state_from_action=true``, so observation.state is
derived from the action column during training. At inference the state must
be provided by the robot — this script uses FK to compute the current EE
pose and gripper position, which it exposes as ``observation.state``.
Pipeline:
1. Read arm joints from robot → FK → observation.state [x,y,z,ax,ay,az,prox,dist]
2. Read camera image → observation.images.cam0
3. pi0 preprocessor (loaded from checkpoint):
- DeriveStateFromActionStep: no-op at inference (state from robot)
- RelativeActionsProcessorStep: caches current state
- RelativeStateProcessorStep: buffers prev state, stacks [prev,cur],
subtracts current → velocity info, flattens
- NormalizerProcessorStep: normalizes
4. pi0 predicts relative action chunk (30 steps)
5. pi0 postprocessor: unnormalize, add cached state → absolute EE
6. IK: absolute EE [x,y,z,ax,ay,az] → arm joint targets
7. Gripper [proximal, distal] → gripper motor targets
8. Send to robot
Usage:
python evaluate.py
"""
from __future__ import annotations
import numpy as np
from scipy.spatial.transform import Rotation
from lerobot.cameras.opencv.configuration_opencv import OpenCVCameraConfig
from lerobot.datasets.lerobot_dataset import LeRobotDataset
from lerobot.model.kinematics import RobotKinematics
from lerobot.policies.factory import make_pre_post_processors
from lerobot.policies.pi0.modeling_pi0 import PI0Policy
from lerobot.processor import RelativeStateProcessorStep
from lerobot.robots.openarm_follower import OpenArmFollower, OpenArmFollowerConfig
from lerobot.scripts.lerobot_record import record_loop
from lerobot.types import RobotAction, RobotObservation
from lerobot.utils.control_utils import init_keyboard_listener
from lerobot.utils.utils import log_say
from lerobot.utils.visualization_utils import init_rerun
# ---------------------------------------------------------------------------
# Configuration — adapt these to your setup
# ---------------------------------------------------------------------------
FPS = 46
EPISODE_TIME_SEC = 60
TASK_DESCRIPTION = "red cube"
HF_MODEL_ID = "pepijn223/grabette-umi-pi0"
# Latency compensation: skip this many predicted action steps to account for
# camera + inference + execution latency. Formula: ceil(total_ms / (1000/FPS)).
# At 46 FPS (~22ms/step) with ~150ms total latency: ceil(150/22) ≈ 7.
# Start with 0 for a safe first test, then increase to match measured latency.
LATENCY_SKIP_STEPS = 0
URDF_PATH = "src/lerobot/robots/openarm_follower/urdf/openarm_bimanual_pybullet.urdf"
URDF_EE_FRAME = "openarm_right_ee_target"
IK_POSITION_WEIGHT = 1.0
IK_ORIENTATION_WEIGHT = 1.0
# ---------------------------------------------------------------------------
# Dataset features for inference
#
# The training dataset has only observation.images.cam0 and action.
# observation.state is derived from action during training
# (derive_state_from_action=true) but must be supplied by the robot at
# inference. We define it here so build_dataset_frame can map FK output
# to the right feature.
# ---------------------------------------------------------------------------
DATASET_FEATURES: dict = {
"observation.state": {
"dtype": "float32",
"shape": [8],
"names": ["x", "y", "z", "ax", "ay", "az", "proximal", "distal"],
},
"observation.images.cam0": {
"dtype": "video",
"shape": [3, 720, 960],
"names": ["channels", "height", "width"],
"info": {
"video.height": 720,
"video.width": 960,
"video.codec": "h264",
"video.pix_fmt": "yuv420p",
"video.is_depth_map": False,
"video.fps": FPS,
"video.channels": 3,
"has_audio": False,
},
},
"action": {
"dtype": "float32",
"shape": [8],
"names": ["x", "y", "z", "ax", "ay", "az", "proximal", "distal"],
},
"timestamp": {"dtype": "float32", "shape": [1], "names": None},
"frame_index": {"dtype": "int64", "shape": [1], "names": None},
"episode_index": {"dtype": "int64", "shape": [1], "names": None},
"index": {"dtype": "int64", "shape": [1], "names": None},
"task_index": {"dtype": "int64", "shape": [1], "names": None},
}
# ---------------------------------------------------------------------------
# FK / IK callables
# ---------------------------------------------------------------------------
class JointsToEE:
"""FK: raw robot observation → flat dict matching observation.state names.
Arm joint positions → EE pose [x,y,z,ax,ay,az] via forward kinematics.
Gripper motor positions → [proximal, distal].
Camera images pass through unchanged.
"""
def __init__(self, kinematics: RobotKinematics, arm_motor_names: list[str]):
self.kin = kinematics
self.arm = arm_motor_names
def __call__(self, obs: RobotObservation) -> RobotObservation:
q = np.array([float(obs[f"{m}.pos"]) for m in self.arm])
t = self.kin.forward_kinematics(q)
rot = Rotation.from_matrix(t[:3, :3]).as_rotvec()
out: dict = {
"x": float(t[0, 3]),
"y": float(t[1, 3]),
"z": float(t[2, 3]),
"ax": float(rot[0]),
"ay": float(rot[1]),
"az": float(rot[2]),
"proximal": float(obs["proximal.pos"]),
"distal": float(obs["distal.pos"]),
}
for k, v in obs.items():
if not k.endswith((".pos", ".vel", ".torque")):
out[k] = v
return out
class EEToJoints:
"""IK: policy action dict → motor position dict for the robot.
Reads [x,y,z,ax,ay,az] from the action, runs IK for arm joint targets.
Passes [proximal, distal] as direct gripper position commands.
"""
def __init__(
self,
kinematics: RobotKinematics,
arm_motor_names: list[str],
position_weight: float = 1.0,
orientation_weight: float = 1.0,
):
self.kin = kinematics
self.arm = arm_motor_names
self.pw = position_weight
self.ow = orientation_weight
self.q_curr: np.ndarray | None = None
def __call__(self, args: tuple[RobotAction, RobotObservation]) -> RobotAction:
action, obs = args
q_raw = np.array([float(obs[f"{m}.pos"]) for m in self.arm])
if self.q_curr is None:
self.q_curr = q_raw
t_des = np.eye(4)
t_des[:3, :3] = Rotation.from_rotvec([action["ax"], action["ay"], action["az"]]).as_matrix()
t_des[:3, 3] = [action["x"], action["y"], action["z"]]
q_target = self.kin.inverse_kinematics(
self.q_curr, t_des, position_weight=self.pw, orientation_weight=self.ow
)
self.q_curr = q_target
out: dict = {f"{m}.pos": float(q_target[i]) for i, m in enumerate(self.arm)}
out["proximal.pos"] = float(action["proximal"])
out["distal.pos"] = float(action["distal"])
return out
# ---------------------------------------------------------------------------
# Main
# ---------------------------------------------------------------------------
def main():
camera_config = {
"cam0": OpenCVCameraConfig(index_or_path=0, width=960, height=720, fps=FPS),
}
robot_config = OpenArmFollowerConfig(
port="can0",
id="right_openarm",
side="right",
cameras=camera_config,
max_relative_target=8.0,
gripper_port="/dev/ttyUSB0",
)
robot = OpenArmFollower(robot_config)
policy = PI0Policy.from_pretrained(HF_MODEL_ID)
policy.config.latency_skip_steps = LATENCY_SKIP_STEPS
arm_motor_names = list(robot.bus.motors.keys())
kinematics = RobotKinematics(
urdf_path=URDF_PATH,
target_frame_name=URDF_EE_FRAME,
joint_names=arm_motor_names,
)
fk = JointsToEE(kinematics, arm_motor_names)
ik = EEToJoints(kinematics, arm_motor_names, IK_POSITION_WEIGHT, IK_ORIENTATION_WEIGHT)
dataset = LeRobotDataset.create(
repo_id="tmp/openarm_eval_scratch",
fps=FPS,
features=DATASET_FEATURES,
robot_type=robot.name,
use_videos=True,
image_writer_threads=4,
)
preprocessor, postprocessor = make_pre_post_processors(
policy_cfg=policy,
pretrained_path=HF_MODEL_ID,
dataset_stats=dataset.meta.stats,
preprocessor_overrides={"device_processor": {"device": str(policy.config.device)}},
)
relative_state_steps = [s for s in preprocessor.steps if isinstance(s, RelativeStateProcessorStep)]
robot.connect()
listener, events = init_keyboard_listener()
init_rerun(session_name="openarm_umi_pi0_relative_ee_evaluate")
try:
if not robot.is_connected:
raise ValueError("Robot is not connected!")
log_say("Starting policy execution")
for step in relative_state_steps:
step.reset()
record_loop(
robot=robot,
events=events,
fps=FPS,
policy=policy,
preprocessor=preprocessor,
postprocessor=postprocessor,
dataset=dataset,
control_time_s=EPISODE_TIME_SEC,
single_task=TASK_DESCRIPTION,
display_data=True,
robot_action_processor=ik,
robot_observation_processor=fk,
)
finally:
robot.disconnect()
listener.stop()
if __name__ == "__main__":
main()