Antidisturbance Tracking Control of Rigid Spacecraft Attitude Systems With Saturation and Asymmetric Constraints

This article addresses the tracking control of rigid spacecraft attitude systems that enable the user-defined error convergence domain, considering input saturation, asymmetric time-varying full-state constraints, event triggering, and disturbance compensation. Specifically, we first employ the Gaussian error function and the barrier Lyapunov function to address the input and full-state constraints. Then, to avoid solving the derivative of the virtual control signal directly, we introduce a command filter to estimate the derivative of the virtual control signal to simplify the controller design. Next, we propose an adaptive dynamic event-triggering mechanism to reduce the communication burden and actuator wear. In addition, the barrier function guarantees that the convergence accuracy of the tracking error is not affected by the triggering mechanism. We design an effective switching self-tuning mechanism to compensate for the adverse effect of the uncertainty term, consisting of the external disturbance and the inertial matrix uncertainty, on the overall attitude system. Finally, the effectiveness and superiority of the proposed scheme are verified by theoretical analysis and simulation comparison.