The growing satellite congestion in Earth orbits increases the risk of Kessler Syndrome, that could potentially hinder humanity's activities in space. This problem could be tackled with Active Debris Removal or On-Orbit Servicing missions. This thesis project aimed to investigate the combined controller approach for OOS mission reach phase, in which both the s/c base and robotic manipulator are actively controlled by a single control system. The multi-body dynamics were defined with the SpaceDyn toolbox in Matlab and the advanced control method was chosen, Model Predictive Control (MPC). The advantage of MPC is the optimization-based strategy, a straightforward definition of constraints and dynamics prediction within the future horizon. The NMPC approach with successive linearization was designed and verified, the controller was tuned and the control system was tested in simulated scenario cases. This study was performed in collaboration with the German Aerospace Center DLR within RICADOS project.