Attitude control and vibration suppression for flexible spacecraft using control moment gyroscopes

This paper presents a novel control strategy for attitude control and vibration suppression of flexible spacecraft. A set of control moment gyroscopes are distributed on the flexible structure of the spacecraft to provide control torques. The interactions between the control moment gyroscopes and the flexibilities of the structure are incorporated in the equations of motion. A nonlinear controller is first formulated to determine the desired control input for large angle three-axis attitude maneuvers and vibration suppression. Then, a steering law is designed to obtain the gimbal commands for the control moment gyroscopes. For the small attitude error stabilization, a simple adaptive controller is developed based on the linearized dynamic model. It can avoid the singularity issue of the control moment gyroscopes, while simultaneously achieving attitude stabilization and vibration suppression. Numerical examples demonstrate the efficacy of the proposed methods.