diff --git a/src/lerobot/processor/delta_action_processor.py b/src/lerobot/processor/delta_action_processor.py
index a75432d50..57d353c5c 100644
--- a/src/lerobot/processor/delta_action_processor.py
+++ b/src/lerobot/processor/delta_action_processor.py
@@ -136,7 +136,16 @@ class MapDeltaActionToRobotActionStep(RobotActionProcessorStep):
             features[PipelineFeatureType.ACTION].pop(f"delta_{axis}", None)
         features[PipelineFeatureType.ACTION].pop("gripper", None)
 
-        for feat in ["enabled", "target_x", "target_y", "target_z", "target_wx", "target_wy", "target_wz"]:
+        for feat in [
+            "enabled",
+            "target_x",
+            "target_y",
+            "target_z",
+            "target_wx",
+            "target_wy",
+            "target_wz",
+            "gripper_vel",
+        ]:
             features[PipelineFeatureType.ACTION][f"{feat}"] = PolicyFeature(
                 type=FeatureType.ACTION, shape=(1,)
             )