Vibration reduction of flexible spacecraft integrating CSVS with distributed piezoelectric actuators during attitude maneuver

The investigation is to apply the component synthesis vibration suppression (CSVS) method and distributed piezoelectric elements technology to the vibration control of a flexible spacecraft actuated by on-off thrusters during maneuvers. The proposed control system includes the attitude controller acting on the rigid hub, designed by the CSVS method based command shaping technique, and the uniform piezoelectric film elements bonded on the surface of the beam appendage, designed by positive position feedback (PPF) control strategy. To extend the CSVS method to the system with the on-off actuators, the pulse-width pulse-frequency (PWPF) modulation is introduced to control the thruster firing and integrated with the CSVS method for reducing the relatively large amplitude vibrations excited by rapid maneuvers. Through CSVS method, an additional independent flexible control system acting on the flexible parts using piezoelectric actuators, which are more suitable for suppression of micro-vibrations can be designed for further vibration reduction. The hybrid control system can improve the performance of the vibration control in both the macro-and micro-senses can result. Both analytical and numerical results are presented to show the advantages of this approach.