Nonlinear Input Shaping Control of Flexible Spacecraft Reorientation Maneuver

This paper presents a design of a novel feedforward controller for a large-angle reorientation maneuver of a spacecraft with exible appendages, such as a telecommunication satellite. The controller combines collocated feedback and feedforward control. It uses an eÆcient and conceptually simple numerical method for the computation for an optimal feedforward input shape for a nonlinear exible system. The method is based on a minimization of a single regularized performance index instead of solution of a terminal control problem. The paper describes a proposed exible spacecraft testbed developed at the Canadian Space Agency, and studies application of the designed control scheme to this testbed. The designed controller is shown to provide excellent performance in compensation of residual exible vibrations for the nonlinear system in question. This work was supported by the Canadian Space Agency contract # 9F028-4-3515/01-XSD yAdjunct Professor, Department of Electrical and Computer Engineering, University of British Columbia, 2356 Main Mall, Vancouver, B.C., Canada V6T1W5, email: [email protected] Directorate of Space Mechanics, Canadian Space Agency, 6767 Route de L'Aeroport, St.-Hubert, Quebec, Canada J3Y 8Y9 1 AIAA Journ. of Guidance, Control, and Dynamics, Vol. 21, No. 2, 1998, pp. 264-270.