Trajectory Planning for De-tumbling Space Debris Using Tethers Based on Radau Pseudospectral Method

The tethered space-tug system which contains a chaser, a target spacecraft and connected by a tether is regarded as a promising way for active debris removal to mitigate the debris level. Based on Radau Pseudospectral Method, this paper investigates the trajectory planning of chaser for de-tumbling the debris target, which is one of most challengeable part in a removal mission. The constraints of collision and tether angle are considered in the path optimization, and a PD controller is designed to track the planned trajectory. Simulation results show that the tumbling spacecraft could be stabilized through the maneuver of chaser and control of tether tension, and closed-loop controller could improve the tracking accuracy.