Adaptive Fuzzy Predefined-Time Dynamic Surface Control for Attitude Tracking of Spacecraft with State Constraints

This study focuses on the adaptive fuzzy predefined-time attitude tracking control problem for rigid spacecraft with inertia uncertainties, external disturbances, and state constraints. In control design, fuzzy logic systems are adopted to approximate the unknown nonlinear dynamics, and a quadratic-fraction barrier Lyapunov function is introduced to ensure that the predefined state constraints are not violated. Compared with the existing dynamic surface control approaches, a novel predefined-time filter and an adaptive fuzzy predefined-time controller are presented, such that the filter error and attitude tracking error can converge to a small region in predefined time simultaneously, where the minimum upper bound of settling time can be exactly preset by tuning one control parameter. Comparative simulation results are carried out to verify the superiority and efficacy of the presented strategy.