Input shaping based adaptive attitude control for flexible spacecraft

Aiming to the attitude control problem for the flexible spacecraft rest-to-rest fast maneuver, an adaptive attitude control method based on input shaping is proposed, which can solve the pitch-yaw-roll control coupling problem and improve the control precision significantly. The attitude dynamics is established considering elastic vibration, actuator failure, and inertial uncertainty. A reference attitude trajectory design method is proposed based on Euler-axis concept, which could avoid the usual pitch-yaw-roll coupling problem in many existing methods. In order to suppress elastic vibration, a multi-mode zero vibration and derivative input shaper is designed to reshape the Euler-axis based reference attitude trajectory. The adaptive fault-tolerant control method is adopted to track the reshaped reference attitude trajectory, so that flexible spacecraft could execute fast attitude maneuver task. Numerical simulations indicate that, compared with the classic PD attitude control method, the proposed adaptive attitude control method can reduce the residual elastic vibration amplitude and attitude control deviation by two orders of magnitude, which verifies the effectiveness of the proposed method.