Fixed-time command filtering adaptive prescribed performance control for high-order uncertain nonlinear systems

To address long convergence time and state constraint challenges in high-order uncertain nonlinear systems, this paper proposes a fixed-time command filtered adaptive prescribed performance control strategy. It constructs an adaptive dynamic constraint boundary via error transformation, overcoming fixed-boundary conservatism in traditional prescribed performance control. A fixed-time command filter with error compensation eliminates the “differential explosion” problem in backstepping. Fuzzy logic approximates unknown dynamics with adaptive parameter tuning. Rigorous analysis proves all closed-loop signals are bounded within a fixed time, and tracking error meets prescribed performance. Simulations verify its superiority in convergence speed and dynamic constraints over existing methods.