[Bug Report] ImplicitActuatorCfg 'velocity_limit_sim' and 'effort_limit_sim' does not work, 'stiffness' and 'damping' seems abnormal

[calmdw]

Hi, I notice in the isaaclab_asset fold, there are configuration files for the robot, I noticed in the franka, UR10 and other robot arms are different. How these damping, stiffness parameters decided? Whats the support material?

Problem 1 about the stiffness and damping parameters. In the franka.py file the stiffness and damping are 80, 4 for arm joints, in universal_robots.py file the stiffness and damping are 800, 40 for arm joints. Theoretically, the franka should move faster with more vibration as smaller damping and stiffness, however, when I run the Isaac-Reach-Franka-v0 and Isaac-Reach-UR10-v0. I notice the UR10 robot moves more faster with vibration.

Problem 2 about the effort_limit and velocity_limit, it seems they does not work, still in the franka-reach environment, the franka robot's movement looks same when I set the velocity_limit to be 0.2 and 2.

System Info

Describe the characteristic of your environment:

• Commit:
• Isaac Sim Version: [e.g. 2022.2.0, this can be obtained by `isaacsim 4.5.0'
• OS: [Ubuntu 22.04]
• GPU: [RTX 4090]
• CUDA: [12.2]
• GPU Driver: [535.183.01]

Additional context

Add any other context about the problem here.

Checklist

• I have checked that there is no similar issue in the repo (required)
• I have checked that the issue is not in running Isaac Sim itself and is related to the repo

Acceptance Criteria

Add the criteria for which this task is considered done. If not known at issue creation time, you can add this once the issue is assigned.

• provide one reason
• one solution to solve the problem as the robot move too fast in the simulation, like punching into the target which is really dangerous in real experiment.

[RandomOakForest]

Thank you for posting this. Could you please add a title and the system info to your issue? Thanks.

[calmdw]

Thank you for posting this. Could you please add a title and the system info to your issue? Thanks.

Sorry, I just notice it and add the name on it.

[calmdw]

Hi, could we also add some text about some common range or how to choose the parameters on the actuators tutorial. Especially for sim2real part.

https://isaac-sim.github.io/IsaacLab/main/source/overview/core-concepts/actuators.html#actuators

[RandomOakForest]

These parameters are empirically set. You may find useful the Gain Tuner Extension in the process of selecting your parameters. Would it be possible for you to use this tool to review your Problems 1 and 2? I will move this into a discussion for the team to follow up. Thank you.

[calmdw]

Thanks for your quick reply! I will check it recently and give it back, if it works well, maybe we could add something more in the document.