Mecanum wheels simulation not stable

Hello,

I have been working with a custom robot model with mecanum wheels. I have imported this robot from a STL file and attached the O3dyn robot’s wheels by rescaling it, kinda similar to this video. I am mostly following this tutorial but the problem is whenever I hit the play button the robot is still but the moment I am giving velocity command the robot starts jumping around.

Here is a video.

What could be is here. I also get this error message in the terminal “[Error] [omni.physx.plugin] Transformation change on non-root links is not supported. Link: /robot/body”