Abstract: The single gimbal control moment gyro, used in spacecraft attitude control system, deserves special attention in recent years due to its large control torque. However, the singularity problem is the major constraint on rapid attitude maneuver, especially in a continuous maneuver process, the spacecraft should escape from singularity rapidly. In this paper, based on the angle between desired control torque and output torque from CMG, a new singularity measurement is introduced. An improved  singularity robust steering law are proposed, and a Gaussian function is adopted to determine the singularity robust coefficient. Simulation results demonstrate that compared with the traditional gradient null motion method, the proposed algorithm can finish attitude maneuver more quickly. It assures the singularityescape more rapidly and reduces attitude chattering magnitude.

Key words: single gimbal control moment gyros, attitude maneuver, CMG steering law, singularity robust