If I now just pick a hand for example, and move it then it just floats away…
There must some kind of kinematic joint system already on this. How do I use it?
So I do not need Franka now. My question still is the same, how can I control this in linear animation? Are the joints structured so I can rotate the upped arm and rest of the arm parts follow?
You can control the movement of the arm by applying target joint positions, target joint velocities or joint efforts on the articulation itself. You can also teleport the robot to a specific joint configuration by using set_joint_positions. We recommend following these tutorials: