Abstract: Singularity problem of single gimbal control moment gyros (SGCMGs) always exists in practical applications. In this paper singularity index is regarded as the path constraint, and gauss pseudospectral method is used in optimizing trajectory. Then a group of nonsingularity gimbal angles and gimbal rates can be obtained as open loop control commands. Considering the effect of the initial attitude errors and external disturbance, reaction wheels (RWs) are introduced to modify the tracking errors and a feedback control law is designed based on Lyapunov stability method. Numerical simulation suggests that with the help of RWs, the nonsingularity SGCMGs commands are also executed strictly and the optimal trajectory can be tracked well under the influence of external disturbance.

Key words: hybrid actuators, gauss pseudospectral method, nonsingularity gimbal angles, trajectory programming, attitude maneuver