Active vibration control and attitude tracking of flexible spacecraft via robust backstepping sliding mode technique

A dual-loop robust control approach is presented for the attitude tracking control and vibration damping of a spacecraft with flexible appendages. Based on the sliding mode control (SMC) and backstepping technique, a attitude tracking controller is derived to control the attitude motion of spacecraft, in which the asymptotic stability is analized by using a Lyapunov method and the reaction wheel dynamics is also considered from the real applications point of view. For actively suppressing the induced vibration, strain rate feedback control methods are provided by using piezoelectric materials as additional sensors and actuators. Numerical simulations are performed to show that both tracking maneuver and vibration suppression can be accomplished effectively.