Mecanum wheel robot in isaac sim

Hi everyone, I tried to create mecanum wheel robot in Isaac sim. I copy the mecanum wheel from O3dyn robot and create a simple robot like the photo. However, then I control the robot to move horizontally by setting velocities for 4 joints correspond to 4 wheels, It moves very strangely, as if there is a sliding phenomenon between the roller wheels and the floor.
I created a new material which I can refine the friction factors. I tried a lot of values for the static and dynamic firction factors (from 0.5 to 50), as a result, the robot movement changed, still really weird, not move horizontally.
I also tested with the O3dyn robot with the same experiment to control the robot move horizontally. The result was similar, it moved really weirdly.
Can you help me please :((

Hi @Huynn,

We have succesfully implemented a 4-wheel mecanum driven mobile base using the O3dyn model as inspiration. There is an interesting discussion on it here as well: Have anyone had success with Mecanum wheels on isaac? - #13 by magokeanu

The mecanum motion can be achieved without much tweaking of the physicsScene and collisions, unfortunately I do not think tweaking the physicsMaterial settings will help much (believe me I have been down the same rabbit hole).

Perhaps you can record a short video of your robot moving with collision view on, then I can take a closer look. Or even better in the simulation debug window enable ‘Contact Normal’ and ‘Contact Point’ so these are visible in the video as well.

Hello @scn, I’m glad to receive your answer to this topic. Because I see quite a few people interested in omni-direction robots in isaac sim. This is the video I recorded video-link

Hi Huynn,

Sorry for the delay, I am taking a closer look now and will get back to you in a few :)

Observations:

  • There seems to be collisions happening for rollers that are not interacting with the floor, these could possibly affect the robot base such that the final movement is messy.
  • You could try to eliminate the effects of masses by driving your joints using acceleration instead of force to further isolate the issue

I will see if i can record a video of my setup here and share it with you.

Screenshot from 2024-05-15 09-47-38
Screenshot from 2024-05-15 09-48-03

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Appreciate brother

Sorry, I re-upload my model, I renamed of joints for driving mecanum wheels to body_joint so that you can easy to track. basic_four_mecanum_robot_after_add_friction_for_rollers_2.usd

This new video goes into different types of mobile robots, take a look! https://www.youtube.com/watch?v=XEri32NaLYk

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Thank you, I will check it out. You are from Road Balance Robotics ? Nice video !