Practical predefined-time fault-tolerant tracking control of autonomous surface vehicles subject to faults and saturation

Abstract

In practical engineering applications, timely fault detection and estimation are often critical, while time-consuming fault detection processes can lead to system instability or significant performance degradation. To address this issue, a practical predefined-time convergence mechanism has been developed. This mechanism starts with an introduction to fault detection, followed by the design of a predefined-time fault estimation approach. Subsequently, a practical predefined-time fault-tolerant controller, along with a theoretical proof of the proposed control algorithm, is provided. A new scheme for singularity avoidance is introduced, ensuring that tracking errors do not approach infinity near the origin. The effectiveness of this approach is verified through its application to unmanned surface vessels for trajectory tracking, where it outperforms traditional fixed-time and predefined-time controllers. Its key characteristics include simple operation, remarkable effectiveness, and intuitive display. Ultimately, this research enhances the transient stability and robustness of unmanned ships control under non-ideal conditions and environments.