A Space Robotic System Used for On-Orbit Servicing in the Geostationary Orbit

The failures of GEO (Geostationary Orbit) spacecrafts will result in large economic cost and other bad impacts. In this paper, we propose a space robotic servicing concept, and present the design of the corresponding system. The system consists of a 7-DOF redundant manipulator, a 2-DOF docking mechanism, a set of stereo vision and general subsystems of a spacecraft platform. This system can serve most existing GEO satellites, not requiring specially designed objects for grappling and measuring on the target. The serving tasks include: (a) visual inspecting; (b) target tracking, approaching and docking; (c) ORUs (Orbital Replacement Units) replacement; (d) un-deployed mechanism deploying; (e) extending satellites lifespan by replacing its own controller. As an example, the servicing mission of a malfunctioned GEO satellite with three severe mechanical failures is presented and simulated. The results show the validity and flexibility of the proposed system.