Research On Heading Control And Path Following Of Unmanned Surface Vessels

Unmanned Surface Vessel(USV)is a small unmanned intelligent platform,which can carry out self-planning and autonomous navigation on the water surface.USV has become a research hotspot of intelligent marine equipment at home and abroad due to its small size,strong maneuverability,fast speed and wide range of applications.The motion control of USV is the core content of its development.Excellent control performance is the prerequisite for the successful implementation of various tasks of USV.In addition,the USV generally does not have side thrusters,making it a typical underactuated system.Based on the six-degree-of-freedom(6-DOF)motion model of USV,considering the environmental disturbances and nonlinear damping of the USV,the nonlinear underactuated first-order nonlinear response model and three-degree-of-freedom(3-DOF)motion model of the USV are established through reasonable simplification.In the study of USV’s heading control,a robust adaptive fuzzy neural network controller is designed based on improved bacterial foraging optimization algorithm and generalized dynamic fuzzy neural network for USV heading control.Then the stability of the controller is proved by Lyapunov stability theory.Finally,considering the disturbance of wind,wave and current,the heading controller of USV is verified by the laboratory computer simulation platform.In terms of the USV’s linear path following control problem,the path following controller which uses classical line-of-sight method is modified by backstepping method.At the same time,a self-adaptive renewal circle replaces the original method of classical line-of-sight method,which successfully solves the problem that classical line-of-sight method is too sensitive to the initial value and ignores the longitudinal velocity control.Finally,considering environmental disturbances,the effectiveness of the linear path following controller of USV is verified by the laboratory computer simulation platform.In terms of the USV’s curved path following control problem,the expected course angle and virtual line velocity of curve path following are designed based on the improved line-of-sight method.Then,the path following controller of USV based on dynamic fuzzy neural network is designed by combining backstepping method and Lyapunov stability theory.Finally,under the environmental disturbances,using the laboratory computer simulation platform verify the improved line-of-sight curved path following controller’s effectiveness and superiority.Based on the underactuated USV’s three degrees of freedom motion model,considering the nonlinear damping and environmental disturbances,the heading control,linear path following and curved path following control of underactuated USV are studied systematically,which can provide some reference for the design and development of USV motion control systems.