Design And Implementation Of Obstacle Avoidance System For Multiple Unmanned Ship

With the rapid development of water operation technology,unmanned ship is widely used as an important tool for water operation.The traditional motion control of unmanned ship mainly focuses on the motion control of single unmanned ship,and there is little research on the formation cooperative control of unmanned ship cluster.With the development of science and technology,the formation technology of multi unmanned watercraft system has a very high application value in both military and civil fields.More and more scholars are devoted to the study of formation control of multi unmanned watercraft systems.Therefore,this paper takes the underactuated unmanned ship as the experimental object and the unmanned ship cluster formation as the task,and focuses on the cluster formation and obstacle avoidance of multi USV formation,and carries out the feasibility analysis.The main research contents are as follows:In this paper,the concept of multiple virtual pilots is derived on the basis of navigation following.Each unmanned ship is provided with its own virtual pilots to follow.The multiple virtual pilots are simplified into a first-order multi-agent model,and the formation control problem is transformed into a trajectory tracking problem.Each virtual pilot point forms a formation distribution with the virtual center point,so that the unmanned ship can track its own virtual pilots to form a formation.Aiming at the obstacles in the path of tracking virtual point formation control and the problem of collision avoidance between formations,the potential field force for obstacle avoidance and collision avoidance of unmanned boats is designed by using the artificial potential field method.In addition,there is a local minimum problem in the process of multi unmanned ship formation movement,which is analyzed and discussed in two states.In terms of underactuated unmanned ship experimental platform,pixhawk flight control board,GPS module,RTK,Zig Bee data transmission module,etc.are used to build the unmanned ship physical experimental platform.The lower computer design is completed on the basis of Px4 flight control software,and the secondary development of QGC ground station is used to realize the control and status information receiving and sending functions of the unmanned ship.The control law is designed by Lyapunov stability theory,and the effectiveness of the control law and obstacle avoidance potential field force is verified by MATLAB simulation.The underactuated unmanned ship experimental platform is placed on the static water surface for physical experiments,mainly including waypoint navigation test,formation tracking test and obstacle avoidance test.