On-Orbit Servicing (OOS) represents the advent of a new approach to space access and promises to be a key element in developing the future space infrastructures. Upcoming robotic spacecraft, mounting a robotic arm, may be able to perform a wider range of operations on a larger number of client spacecraft such as docking, berthing, refueling, repairing, upgrading, transporting, rescuing and orbital debris removal. Space manipulator systems, however, introduce relevant challenges due to the dynamic coupling between the manipulator and the spacecraft, that represents its base, and due to the growing need for autonomy and flexibility to perform new tasks and adapt to environment changes and disturbances.