Robust attitude control design for a spacecraft with articulating appendages

Abstract

A practical approach to robust control design involving structured uncertainties is proposed to reduce control design complexity in terms of the controller design process and the controller order as well. The design approach iterates on mixed H^/Hoo control objectives with real block diagonal scaling matrices, yielding a sub-optimal controller without introducing extra states to the controller design. This approach is applied to the spacecraft attitude control and momentum management problem. A general modeling formulation for robust attitude control systems of a low-altitude earth orbiting spacecraft is presented. The practicality of the proposed design approach is demonstrated for the Space Station attitude control problem by incorporating the plant and environmental uncertainties in the controller design.