Robust Backstepping Control for Agile Satellite Using Double-Gimbal Variable-Speed Control Moment Gyroscope

摘要

The work addressed in this paper focuses on the attitude maneuver control of the agile satellite installed with only one double-gimbal variable-speed control moment gyroscope. First, the mathematical model of the agile satellite is presented, in which the gimbal angular rates and wheel acceleration are considered as the control input variables. Based on the output torque equation of the double-gimbal variable-speed control moment gyroscope, the singularity problem is analyzed. Next, a nonlinear, robust backstepping control method, which directly calculates the gimbal angular rates and wheel acceleration commands, is proposed for attitude maneuver control. The proposed controller effectively compensates the influences of external disturbance torques and the uncertainties of the moment of inertia parameters presented in the agile satellite dynamics. Moreover, a small value is introduced to avoid the divergence of control input commands caused by the singularity state. Simultaneously, the physical limitations of the control moment gyroscope are taken into consideration in the controller design. Finally, numerical simulations are carried out to demonstrate whether one double-gimbal variable-speed control moment gyroscope could accomplish the attitude maneuver control of the agile satellite and to validate the effectiveness of the proposed control method.