Integrated position and attitude control for autonomous docking based on backstepping and input-to-state stability

In this paper, the spacecraft rendezvous and docking problem with target spacecraft on an arbitrary elliptical orbit is investigated. A nonlinear integrated position and attitude dynamics model is established. With Lyapunov analysis, an integrated position and attitude controller is proposed based on input-to-state stability (ISS) in the presence of torque uncertainty and external disturbances. Finally, simulation results are presented to illustrate the effectiveness of the presented approach.