Designed Steering Law for the Hybrid Actuators of Single Gimbal Control Moment Gyroscopes and Reaction Wheels Array

Single Gimbal Control Momentum Gyroscopes (SGCMG) are widely used with the ability of large torque output and high accuracy control of a spacecraft. The singularity problem (especially the internal elliptical singularity) of SGCMG becoming a major obstacle in successful implementing the task of the attitude control. The singularity can be effectively avoided by additional reaction wheel (RW) array in the field of the actual application. Unfortunately, the saturation problem is existed in the RW. In this paper, the hybrid actuators of the SGCMG with pyramid configuration and RW array with orthogonal configuration is considered. The new steering law is proposed. Consequently, the internal elliptical singularity and the saturation problem of the RW can be effectively avoided by the new steering law at the same time.