Adaptive practical fixed-time synchronized tracking control of ASV with prescribed performance

This paper investigates the problem of adaptive practical fixed-time synchronized tracking control of autonomous surface vehicle (ASV) systems with model uncertainties and external disturbances. In order to force the tracking error to a required range, a piecewise continuous finite-time prescribed performance function (FTPPF) is employed. A sliding mode controller incorporating FTPPF is built based on the norm-normalized (NN) sign function to simultaneously follow the desired trajectory. A set of adaptive laws is proposed to estimate model uncertainties and external disturbances with the constructed sliding mode surface. Then, an adaptive sliding mode controller is designed to achieve prescribed dynamic convergence performance and tracking accuracy. Mathematically, the practical fixed-time stability of ASV systems is firmly proven and all the signals in the closed-loop system are bounded. Finally, simulations are performed utilizing Matlab/Simulink to show the availability of the acquired algorithm.