Allow max_relative_target to be a float (#1837)

* Remove unused max_relative_target for stretch3

* Fix type annotation and allow integer max_relative_target values

* Configure max_relative_target to be floats instead of ints

* Update docs and types to reflect that max_relative_target can be a dict

* Remove unnecessary isinstance check for ints

* Fix typo in name

---------

Co-authored-by: Justin Huang <[email protected]>

Author: jstnhuang

src/lerobot/robots/bi_so100_follower/config_bi_so100_follower.py

@@ -29,10 +29,10 @@ class BiSO100FollowerConfig(RobotConfig):
 
     # Optional
     left_arm_disable_torque_on_disconnect: bool = True
-    left_arm_max_relative_target: int | None = None
+    left_arm_max_relative_target: float | dict[str, float] | None = None
     left_arm_use_degrees: bool = False
     right_arm_disable_torque_on_disconnect: bool = True
-    right_arm_max_relative_target: int | None = None
+    right_arm_max_relative_target: float | dict[str, float] | None = None
     right_arm_use_degrees: bool = False
 
     # cameras (shared between both arms)

src/lerobot/robots/hope_jr/config_hope_jr.py

@@ -44,8 +44,8 @@ class HopeJrArmConfig(RobotConfig):
     disable_torque_on_disconnect: bool = True
 
     # `max_relative_target` limits the magnitude of the relative positional target vector for safety purposes.
-    # Set this to a positive scalar to have the same value for all motors, or a list that is the same length as
-    # the number of motors in your follower arms.
-    max_relative_target: int | None = None
+    # Set this to a positive scalar to have the same value for all motors, or a dictionary that maps motor
+    # names to the max_relative_target value for that motor.
+    max_relative_target: float | dict[str, float] | None = None
 
     cameras: dict[str, CameraConfig] = field(default_factory=dict)

src/lerobot/robots/koch_follower/config_koch_follower.py

@@ -28,9 +28,9 @@ class KochFollowerConfig(RobotConfig):
     disable_torque_on_disconnect: bool = True
 
     # `max_relative_target` limits the magnitude of the relative positional target vector for safety purposes.
-    # Set this to a positive scalar to have the same value for all motors, or a list that is the same length as
-    # the number of motors in your follower arms.
-    max_relative_target: int | None = None
+    # Set this to a positive scalar to have the same value for all motors, or a dictionary that maps motor
+    # names to the max_relative_target value for that motor.
+    max_relative_target: float | dict[str, float] | None = None
 
     # cameras
     cameras: dict[str, CameraConfig] = field(default_factory=dict)

src/lerobot/robots/lekiwi/config_lekiwi.py

@@ -39,9 +39,9 @@ class LeKiwiConfig(RobotConfig):
     disable_torque_on_disconnect: bool = True
 
     # `max_relative_target` limits the magnitude of the relative positional target vector for safety purposes.
-    # Set this to a positive scalar to have the same value for all motors, or a list that is the same length as
-    # the number of motors in your follower arms.
-    max_relative_target: int | None = None
+    # Set this to a positive scalar to have the same value for all motors, or a dictionary that maps motor
+    # names to the max_relative_target value for that motor.
+    max_relative_target: float | dict[str, float] | None = None
 
     cameras: dict[str, CameraConfig] = field(default_factory=lekiwi_cameras_config)
 

src/lerobot/robots/so100_follower/config_so100_follower.py

@@ -30,9 +30,9 @@ class SO100FollowerConfig(RobotConfig):
     disable_torque_on_disconnect: bool = True
 
     # `max_relative_target` limits the magnitude of the relative positional target vector for safety purposes.
-    # Set this to a positive scalar to have the same value for all motors, or a list that is the same length as
-    # the number of motors in your follower arms.
-    max_relative_target: int | None = None
+    # Set this to a positive scalar to have the same value for all motors, or a dictionary that maps motor
+    # names to the max_relative_target value for that motor.
+    max_relative_target: float | dict[str, float] | None = None
 
     # cameras
     cameras: dict[str, CameraConfig] = field(default_factory=dict)

src/lerobot/robots/so101_follower/config_so101_follower.py

@@ -30,9 +30,9 @@ class SO101FollowerConfig(RobotConfig):
     disable_torque_on_disconnect: bool = True
 
     # `max_relative_target` limits the magnitude of the relative positional target vector for safety purposes.
-    # Set this to a positive scalar to have the same value for all motors, or a list that is the same length as
-    # the number of motors in your follower arms.
-    max_relative_target: int | None = None
+    # Set this to a positive scalar to have the same value for all motors, or a dictionary that maps motor
+    # names to the max_relative_target value for that motor.
+    max_relative_target: float | dict[str, float] | None = None
 
     # cameras
     cameras: dict[str, CameraConfig] = field(default_factory=dict)

src/lerobot/robots/stretch3/configuration_stretch3.py

@@ -24,11 +24,6 @@
 @RobotConfig.register_subclass("stretch3")
 @dataclass
 class Stretch3RobotConfig(RobotConfig):
-    # `max_relative_target` limits the magnitude of the relative positional target vector for safety purposes.
-    # Set this to a positive scalar to have the same value for all motors, or a list that is the same length as
-    # the number of motors in your follower arms.
-    max_relative_target: int | None = None
-
     # cameras
     cameras: dict[str, CameraConfig] = field(
         default_factory=lambda: {

src/lerobot/robots/utils.py

@@ -70,7 +70,7 @@ def make_robot_from_config(config: RobotConfig) -> Robot:
 
 
 def ensure_safe_goal_position(
-    goal_present_pos: dict[str, tuple[float, float]], max_relative_target: float | dict[float]
+    goal_present_pos: dict[str, tuple[float, float]], max_relative_target: float | dict[str, float]
 ) -> dict[str, float]:
     """Caps relative action target magnitude for safety."""
 

src/lerobot/robots/viperx/config_viperx.py

@@ -28,15 +28,15 @@ class ViperXConfig(RobotConfig):
 
     # /!\ FOR SAFETY, READ THIS /!\
     # `max_relative_target` limits the magnitude of the relative positional target vector for safety purposes.
-    # Set this to a positive scalar to have the same value for all motors, or a list that is the same length as
-    # the number of motors in your follower arms.
+    # Set this to a positive scalar to have the same value for all motors, or a dictionary that maps motor
+    # names to the max_relative_target value for that motor.
     # For Aloha, for every goal position request, motor rotations are capped at 5 degrees by default.
     # When you feel more confident with teleoperation or running the policy, you can extend
     # this safety limit and even removing it by setting it to `null`.
     # Also, everything is expected to work safely out-of-the-box, but we highly advise to
     # first try to teleoperate the grippers only (by commenting out the rest of the motors in this yaml),
     # then to gradually add more motors (by uncommenting), until you can teleoperate both arms fully
-    max_relative_target: int | None = 5
+    max_relative_target: float | dict[str, float] = 5.0
 
     # cameras
     cameras: dict[str, CameraConfig] = field(default_factory=dict)