Robust microvibration mitigation and pointing performance analysis for high stability spacecraft
Résumé
This paper deals with the development of a mixed active-passive microvibration mitigation solution capable of attenuating the transmitted vibrations generated by reaction wheels to a satellite structure. A dedicated simulation environment, provided by the European Space Agency and Airbus Defence and Space industries, serves as a support for testing the proposed solution at satellite level. This paper covers modeling, control system design, and worst case analysis for a typical satellite observation mission that requires high pointing stability. Combined with a novel disturbance model for the reaction wheel perturbations, the pointing performance and stability requirements are reformulated as bounds on the worst-case L2 system gains. Subsequently, the active microvibration controller is tuned to manage the conflicting design goals and optimize different trade-offs between robustness and performance. Finally, robust stability margins and worst-case performance bounds with respect to various system uncertainties, time-varying reaction wheel spin rates, actuator saturation, and time delays are obtained using the structured singular value, integral quadratic constraints, and time-domain nonlinear simulations.