Move PR2 joints in Gazebo (no ROS)

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1

I have gazebo 10 installed on Ubuntu 16, did not install ROS as we plan to apply Reinforcement Learning policy in the simulated environment.

When I applied force/efforts on any joints in the PR2, none of them move. But the same merchanism of joint.SetForce works for R2 and Pioneer2DX, I looked at PR2 simulator code in ROS, in the end, it seems also call joint.SetForce.

I am really confused, anyone knows how I could get PR2 moving in Gazebo only environment??

Thanks