[Question] Obtain XY contact forces from contact sensor in IsaacLab

[arjun-2612]

Question

How do I obtain the XY forces from contact sensor? I am seeing that the net_forces_w only gives the Z force, but I need the XY as well. Is there a way to do this?

[PeterL-NV]

Hi, To access tangential (friction) forces, you can use the PhysX contact sensor view provided in Isaac Lab:

sensor.contact_physx_view.get_friction_data(dt)

[Mayankm96]

@jtigue-bdai for vis. We are working on supporting this directly.

[jtigue-bdai]

Yep PR up: #3563

[arjun-2612]

I tried this in my own implementation. The friction force isn’t what I want to see.

So basically I am implementing QP stance leg control on the Unitree go2 and other quadrupeds. I want to validate that the applied contact force matches what the QP asks for. I found that the magnitude of the friction forces here is not the same as the QP, and the visual just points roughly straight up.

Please verify if this is possible to obtain through contact sensor in isaaclab.

[jtigue-bdai]

I tried this in my own implementation. The friction force isn’t what I want to see.

So basically I am implementing QP stance leg control on the Unitree go2 and other quadrupeds. I want to validate that the applied contact force matches what the QP asks for. I found that the magnitude of the friction forces here is not the same as the QP, and the visual just points roughly straight up.

Please verify if this is possible to obtain through contact sensor in isaaclab.

Is your environment on flat ground?