Quaternion Based Sliding Mode Attitude Controller for a Spacecraft with Control Moment Gyros

This paper proposes a quaternion based robust sliding mode attitude controller for a spacecraft with Single Gimbal Control Moment Gyros (SGCMGs) for rest to rest maneuvers, in presence of uncertainties. The power rate reaching law has been used to guarantee convergence in the proposed technique and stability has been analysed using Lyapunov's stability theorems. The inherent singularity problem in SGCMGs has been avoided here by making use of the robust singularity inverse steering logic. The simulation analysis shows the efficacy of the proposed controller.