NVIDIA
[REQ] Joint Friction
Description
As far as I can see, wp.sim joints are implemented as frictionless joints. It would be great if they supported a simple friction model to enable more realistic simulation.
Context
In real-world scenarios, joint friction often consumes a majority of the joint torques produced by motors. While exact friction models really depend on the hardware used, a simple abstraction often can help to reduce the sim2real gap significantly.
IsaacSim seems to use a Stribeck function. I believe that (also in consistency with the rest of the library), the commonly used combination of Coulomb and viscous friction could be a good choice for warp.
For the sake of differentiability, a sigmoidal friction model as presented in this paper (25) might also be a good option.
