Hybrid inverse dynamics control of a free-flying space robot in contact with a target satellite

This paper presents an inverse-dynamics-based control approach of a free-flying space robot manipulator interacting with a target satellite. The proposed controller handles the overall combined coupled dynamics of the based-satellite servicing robot and the passive target satellite all together with geometric and momentum constraints imposed on the system. A reduced-order dynamical model is obtained by finding a common solution of all constraints using the concept of orthogonal projection matrices. The proposed controller does not only show the capability to meet motion and contact forces desired specifications, but also to cope with the unactuation problem of the target satellite due to its thrusters' failure or shutdown. Finally, simulation results demonstrate the effectiveness of the proposed controller