Robotic in-orbit servicing has yet to be realised due to a number of technical difficulties. One such difficulty is analysed here. The requirement for force control in robotic manipulation imposes significant design requirements on space robots by virtue of the lack of a mounting platform to react against external forces and torques. The spacecraft attitude control system must effectively serve the same role as the ground in terrestrial manipulators. The reaction torques imposed on the spacecraft due to the manipulators is high when force control is used in grappling targets in space, limiting the choice of attititude actuator to control moment gyroscopes.
Aeronautical Journal
Department of Mechanical and Aerospace Engineering

Ellery, A. (2004). Robotic in-orbit servicers - The need for control moment gyroscopes for attitude control. Aeronautical Journal, 108(1082), 207–214. doi:10.1017/S0001924000000117