[Question] Franka Lift Cube RL with IK / OSC control

[jiwonyou0420]

It seems that for Franka Lift Cube RL, only joint pos control is supported.

I'm trying to do Franka Lift Cube RL with IK / OSC control, and I would appreciate any help.

I added skrl cfg entry point to the registered Isaac-Lift-Cube-Franka-IK-Rel-v0 so that I can run RL. I'm using the same skrl_ppo_cfg.yaml that is used for franka lift cube, joint pos env.

However, with default ik_rel_env_cfg.py, arm motion diverged and learning failed.

After tuning the scale down(0.5 -> 0.08), Franka can grasp the cube but most of the time fails to bring it to goal position(sometimes succeeds, but with strange motion)

@configclass
class FrankaCubeLiftEnvCfg(joint_pos_env_cfg.FrankaCubeLiftEnvCfg):
    def __post_init__(self):
        # post init of parent
        super().__post_init__()

        # Set Franka as robot
        # We switch here to a stiffer PD controller for IK tracking to be better.
        self.scene.robot = FRANKA_PANDA_HIGH_PD_CFG.replace(prim_path="{ENV_REGEX_NS}/Robot")

        # Set actions for the specific robot type (franka)
        self.actions.arm_action = DifferentialInverseKinematicsActionCfg(
            asset_name="robot",
            joint_names=["panda_joint.*"],
            body_name="panda_hand",
            controller=DifferentialIKControllerCfg(command_type="pose", use_relative_mode=True, ik_method="dls"),
            scale=0.08, # originally 0.5
            body_offset=DifferentialInverseKinematicsActionCfg.OffsetCfg(pos=[0.0, 0.0, 0.107]),
        )

20250822_134105.mp4

Is this a bug or can it be solved with controller / RL hyperparameter tuning? In general, what would be good practice for using IK / OSC controller in RL? what changes should I make to ik_rel_env_cfg.py of franka lift cube?

I'm using Isaacsim 5.0, rtx 5080, driver 570, ubuntu 22.04

Thanks in advance