Simulation weird behaviour in standalone application

Omniverse Isaac Sim
1

Isaac Sim Version

4.5.0

Operating System

Ubuntu 22.04

GPU Information

  • Model: RTX 4070TI
  • Driver Version: 550.144.03

Physics simulation issues in Isaac sim

Standalone simulation app vs UI

I have a USD file of rack (with holes) and tube. I am trying to create synthetic data, thus placing tubes in rack.

  • I have created USD file for rack, tube and defined all mesh properties.
  • rack is static collider
  • tube is rigid body
  • When assembled in UI it works without issue

In python script if i load the seperate USD files of tube and rack and do same simulation tube is not perfectly sloted in rack, tube behaves in weird way.

Below is result from standlone script of python, the USD files are same. Any reason why.

Additional Information

I checked mass of tube it is 25 grams - 0.0252 in both cases. All simulation settings is same.

3

Hi @aakash.chandran, thank you for posting your question. From the videos it seems to me like in the second video you are starting simulation while the tubes are already colliding with the rack, that can cause a large initial force and knock them off. It should work if you position the tubes such that they are above a hole. One tip is to use a simpler collider for the test tubes, you can go to the Collider properties and choose Approximation to be Convex Hull.

Let me know if you are still having issues after those suggestions..

Michael