Nonfragile Super-Twisting Disturbance-Observer-Based Inverse Optimal Control for Spacecraft With Integrated Dynamics

This article investigates a robust inverse optimal control strategy based on nonfragile super-twisting disturbance observer to achieve orbit–attitude–vibration stabilization simultaneously subject to external disturbance and observer gain perturbation. Considering additive gain perturbation, a nonfragile super-twisting sliding-mode disturbance observer is developed to estimate the external disturbance with convergence condition formulated as linear matrix inequality. Based on disturbance compensation, the inverse optimal controller is proposed to achieve orbit maintenance, attitude stabilization, and vibration suppression for the nonlinear coupling dynamic system. Numerical simulations are performed to demonstrate the effectiveness and superiority of the proposed control strategy.