Behavior of DOF_MODE_POS

Autonomous Machines Robotics - Isaac Isaac Gym
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We can always set the position drive target and velocity target via set_dof_velocity_target_tensor and set_dof_position_target_tensor, even when the set the control mode to be position control, i.e. DOF_MODE_POS.

In this DOF_MODE_POS mode, how will the velocity target and damping take effect? Which is the correct case, A or B?
A. damping is set to be 0 internally regardless of user specified value. So velocity target will have no effect. It will lead to a simple proportional position control.
B. velocity target is set to be 0 internally regardless of user specified value. Thus it will have a damping effect when the actual dof_velocity is not 0. In this case, the controller will be a PD position control, where P is the stiffness and D is the damping.

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Get some insights from Issac developer Kier Storey, thanks a lot!

The correct answer should be B. The damping parameters are still being used even in DOF_MODE_POSmode. The stiffness term drives towards a target position and the damping term drives towards a target velocity. It is also recommended to set a moderate damping value not matter which mode you are using to get stable simulation results.

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