H∞ control using tensor product model transformation
In this paper a combined controller composed of the H∞ virtual controller and the sliding mode controller is proposed to improve the rigid spacecraft robustness. Considering the strong nonlinearity of the spacecraft dynamics, tensor product (TP) transformation is applied on the linear parameter varying (LPV) model which is obtained from the attitude kinematics system. The TP-based H∞ controller can be optimized by linear matrix inequality (LMI) tools off-line. Moreover, an integral sliding mode (ISM) attitude controller which enhances the robustness of the whole system is designed to track the output of the proposed H∞ virtual controller. The global stability of the nonlinear system can be guaranteed in large attitude maneuver with external disturbance and inertia uncertainties. Simulation results verified the effectiveness of the proposed algorithms.