固定时间预测器下的欠驱动无人艇路径跟踪控制

Unmanned surface vehicles (USVs) is a kind of smart ship that moves autonomously on the water. It has the characteristics of automation, high speed and underactuation, and can be applied to both civil and military fields. This paper developed a new fixed-time convergence predictor based on the LOS (line-of-sight) guidance law for path following tasks of underactuated vehicles, to predict position error and estimate external disturbance. The convergence time of the fixed-time predictor does not depend on initial state and converge faster compared with the finite-time predictor-based guidance law. Besides, a fixed-time controller is designed to ensure effective convergence of tracking controller. It controls the steering torque, applying to the tail of the USV, which makes heading angle converge to the desired value in fixed-time. Finally, simulation experiments demonstrate that the proposed guidance law and controller can follow the given path accurately.