Abstract
This paper proposes a new method for avoiding a singularity problem what is peculiar to the CMG system. The proposed controlling law utilizes the singular value decomposition (SVD) to obtain singular vectors and generates the command gimbal rate that keeps the command torque in the direction orthogonal to the singular direction with a maximum gain. Capability of the present method in singularity avoidance was demonstrated with numerical simulations for attitude tracking control of a small satellite using four SGCMGs.