Vessel heading tracking fixed time control with preset performance

This study provides a fixed-time control approach with presettable performance, aiming at the nonlinear ship heading model with parameter uncertainty, input saturation, and unknown external environmental perturbations. In order to overcome input saturation, the method uses an auxiliary power system, a finite-time auxiliary observer to estimate the integrated perturbations, a preset performance function to constrain the tracking error, and a normalized error transformation function to avoid the traditional preset performance control technique's dependence on the system's initial state. The developed controller ensures that the closed-loop direction tracking system is fixed-time stable, as demonstrated by the Lyapunov stability study. Was mimicked by a 45-meter mockup of an unmanned ship. The outcomes are as follows: the unmanned ship's heading tracking error converges to the designated region in the allotted time, and the proposed controller has strong resilience and can handle both model parameter uncertainty and outside disturbances like wind and waves.