Isaac sim caster physics setting

Omniverse Isaac Sim
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1

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Isaac Sim Version

4.5.0
4.2.0
4.1.0
4.0.0
4.5.0
2023.1.1
2023.1.0-hotfix.1
Other (please specify):

Operating System

Ubuntu 22.04
Ubuntu 20.04
Windows 11
Windows 10
Other (please specify):

GPU Information

  • Model: RTX2080 super
  • Driver Version: 550.120

Topic Description

Detailed Description

Caster does not rotate when robot rotates.
It mirrors Carter’s physical properties.
When robot is pulled, Caster does not move and behaves strangely.

Error Messages

(If applicable, copy and paste any error messages you received)

Screenshots or Videos

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Additional Information

What I’ve Tried

(Describe any troubleshooting steps you’ve already taken)

Related Issues

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Additional Context

(Add any other context about the problem here)

3

Hello, there can be many reasons for this. The joint needs to be defined correctly between the main body and the caster. What behavior are you getting when you try to move the joint on hitting play? Can you please share the USD file/repro for this issue?

4

hello_diff_robot.zip (2.2 MB)
This is my usd file.
Thank you.

5

Thank you for providing the usd to reproduce it. It seems like the problem you have is that you have enabled self-collision in your robot and there are bodies that are always in collision like the caster wheels with the platform rigid body. One quick way to fix this is to disable self-collision since for your case, I don’t think it is necessary.

How to check that bodies are in collision? You can visually do this by enabling mesh collider visualization (click on eye logo in GUI, Show by Type>Physics>Colliders>All) and you will see that the collider mesh of the caster wheels and the big wheels are intersecting the plate.

Here is a video of with self-collision on and off. Sorry I couldn’t figure out how to show my cursor in the screen capture.