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leggedrobotics / raisimLib

RAISIM, A PHYSICS ENGINE FOR ROBOTICS AND AI RESEARCH
http://www.raisim.com
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Calling getLinearVelocity() on a kinematic object #54

Closed christophecricket closed 4 years ago

christophecricket commented 4 years ago

Hi There I have a simulation where I am imposing a position on a kinematic object, and trying to read its velocity with getLinearVelocity(), but the output I get is 0. Is this something I'm doing wrong on my side, or is this expected behaviour?

The same method seems to work fine for an object I have set to dynamic.

jhwangbo commented 4 years ago

I just tested the code and it works for me. For kinematic objects, the velocities don't change. So you set them to certain numbers and they remain the same. You can assign both linear and angular velocities with setVelocity. If you didn't set them, they are zero by default.

christophecricket commented 4 years ago

Aha, gotcha. I thought World.integrate() might differentiate the position command as part of the engine's inner workings. Good to know, I guess I'll compute/read velocity some other way, then. Thanks!