The Study On Motion Control And Swarm Coordinated Planning For Unmanned Surface Vehicles(USV)

Recently,along with highly attention paid on the exploration and exploitation of marine resources and maritime security,Unmanned surface vehicles(USV)have become an intense research area because of their extensive military and civil applications.In addition,along with the further research of USV and the demand of unmanned combat,the concept of swarm control for multi-USVs has been put forward.Swarm collaborative control has a wide application prospect in aspects of marine resources detection,fleet cooperative engagement,searching and rescue,wing patrol,environment monitoring,etc.Thus,this paper takes the intelligent navigation of USV swarm as the research object,and mainly make the following work:First,a practical water jet propulsion USV is taken for example,and the three degrees' motion equation in horizontal plane is established.In the process of movemtn modeling,the problem of model perturbation has been considered,and the study of perturbation model has been carried out.By merging all uncertainties together innovatively,a motion model contrains total uncertain disturbance function has been established.meanwhile,taking the water jet HamniltonJet 364 for example,the fitting analysis about the relationship between the thrust,revolving speed,and navigation speed has been made,and established specific control eqution,which laid a foundation for the subsequent chapters of the motion controller design and movement simulation.In view of robust control for underactuated USVs,a new type of adaptive disturbance observer is designed,for the purpose of real-time estimating uncertain perturbation in each degree of freedom.Based on the observer,the sliding-mode control method is used and improved,and the control law of system input(i.e.the thrust and nozzle angle)is designed,and the integration control for navation speed and heading angle is realized.In order to solve the problem of underacuation,the line-of-sight guidance law is adopted in the path tracking for making heading planning.The guidance law is then improved appropriately to satisfy the demand of tracking curved path.Then,based on the motion control algorithm for single USV,the autonomous motion control of USV swarm is further studied.In order to achive the control target of autonomous navigation,a hierarchical control frameword isproposed,and studied in three aspects such as swarm aggregation strategy,individual motion planning and collision avoidance.In aspect of aggregation strategy,this paper proposes a location planning method based on centre position and distances between group members,and a velocity vector based movement planning method is designed.For the problem collision avoidance,the artificial potential field(APF)method is applied in the controller design,and necessary improvement on APF method have been made to make it meet the demand of practical application.On the basis of the above three steps,and combined with the content of robust control for single USV,a comprehensive motion control system is established for swarm autonomous navigation.Finally,the problem of intelligent navigation control for USV swarm is studied,which based on the swarm control framework,and the problem is refined as auto behavior decision making and motion planning.As for the auto decision making,this paper carried out the behavior strategy library design in aspects of swarn path tracking and swarm collision avoidance with navigation ships,and auto movement planning laws are designed for each USV.In order to endow USVs with ability of behavior decision making,specific movement behavior strategies library is designed,through simulations of sailing process,and carring out scenario deduction and designing coping behaviors.By making a variety of navigation and joint operations of complicated task simulations,the ability of auto bebavior decision making is exhibited,and the control target of swarm intelligent navigation under assigned tasks is achieved.