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Question How should I be setting stiffness / damping parameters for articulation bodies?

Discussion in 'ML-Agents' started by superweeniehutjr, Jan 14, 2023.

  1. superweeniehutjr


    Apr 8, 2021
    I'm using articulation bodies for a 'walker' type setup and they're controlled as PD motors in physx, with stiffness being Kp / the P gain (aka what the proportional difference is scaled by) and the damping being Kd / D gain (aka what the derivative, velocity, difference is scaled by)

    I can't find a good resource for finding what the values of these settings are. I set my human up with capsules and set the mass of each body based on the average human mass (of 980 some kg/m^3) but I can't find an equivalent heuristic for to use for the PD motors.

    I saw has a similar setup to mine and there PD gains seemed pretty arbitrary.
  2. GamerLordMat


    Oct 10, 2019

    PID controller values have nothing to do with any physical units. They are just parameters that tune your system, they are a signal that you have to interpret. The amount of force that is produced is up to you, or in this case their is a parameter called something like "angular force/drive" (or something like that).
    So how much torque a human joint can produce is surely somewhere in the internet, or calculate it yourself somehow.