Robust and optimal attitude stabilization of spacecraft with external disturbances

This paper presents a robust and optimal three-axis attitude control scheme for the rigid body motion with external disturbances, in which a worst-case design that the external disturbance signal maximizes the same performance index that the control input minimizes is assumed. After presenting a robust control law for the three-axis attitude control of the rigid body motion with external disturbances, the optimality property of the robust control law is investigated based on the minimax approach and the inverse optimal approach. A numerical example is given to illustrate the theoretical result presented in this paper.