Research And Implementation Of Trajectory Tracking Algorithm Based On Heading Guidance And Control For Unmanned Surface Vehicles

Unmanned Surface Vehicle(USV)is a new type of vehicle that can cruise automatically and perform multiple tasks autonomously in complex marine surface environment.With the international changes in the field of navigation and the strong demand of the public for civil intelligent USV,how to guarantee the accuracy and reliability of the trajectory of USV on the marine surface has become one of the key points.Since USV’s sailing are easily disturbed by external factors such as wind,waves and currents in autonomous movement,and due to the characteristics of non-linear movement,it is of great significance to research the trajectory tracking of USV to expand the potential of marine development and guarantee the life safety of workers.The traditional trajectory tracking method have some problems such as difficult to establish model,adjust parameters,and the control method is simple,so further research on the USV trajectory tracking method is necessary,The research contents in this dissertation are as follows.(1)An L1 heading guidance algorithm with adaptive adjustment of reference position switching radius is proposed.The heading guidance method does not depend on the detail model of the USV,and can calculate the real-time motion heading of the USV based on the reference position point of the trajectory and the speed,and adjust adaptively according to the change of the heading angle to guide the USV for trajectory tracking.(2)A BP neural network-based incremental PID algorithm is designed for the control of the USV heading,automating the way the PID parameters are adjusted.At the same time,the above algorithm is optimised by increasing the inertia term and multi-stage threshold algorithm with deadband,which effectively improves the accuracy and stability of the USV heading control.(3)An USV trajectory tracking control system was designed and hydrostatic trajectory tracking experiments were carried out.The system consists of hardware and software systems and is deployed on a small,low-speed USV.The experiments have verified that the trajectory tracking has achieved satisfactory results.