Control of spacecraft terminal phase rendezvous using On/Off thrusters

Autonomous Rendezvous and docking is an orbital maneuver technology in space explorations where close match of position and velocity vectors is needed. In this context, relative position dynamics coupled with attitude dynamics are considered for low earth orbit rendezvous. Sliding mode control and saturated PD control methods are applied to control the considered coupled dynamics. On/Off thrusters those can be used for controlling both translational and rotational motion are included in the dynamics in the form of On/Off switch. Corresponding results are compared when the system is subjected to flexible and slosh dynamics.