Swarming Decision And Control Of Unmanned Surface Vehicles

Unmanned surface vehicles(USV)have better autonomous navigation and decisionmaking ability than other manned ships of the same class,and have high speed and large carrying capacity,which can perfectly meet the mission requirements of new maritime system.Compared with a single unmanned vehicle,the multi-unmanned vehicles swarm system can cover a wider sea area and have a higher completion efficiency when performing tasks.The USV swarm system is a powerful tool for marine resources survey,maritime defense and other water operations.Therefore,the research on USV swarming decision and control system design in complex marine environment have practical significance.This thesis focuses on the design of the motion decision-making mechanism of USVs,a motion decision-making mechanism with velocity guidance is proposed for the USV swarming system.And aiming at the problems of complex ocean environment,multi obstacles and thruster failure of USV,a control scheme combining observer and sliding mode dynamic surface is proposed.The main work is as follows:Firstly,in order to realize the fully-drive USV swarming motion with internal unknown modeling,a motion decision-making method with velocity guidance is designed.The aggregation and heading consistence of USVs are described by Lyapunov function,and the internal collision avoidance of USV is realized by using artificial potential function.A variable coefficient USV swarming motion decision-making model is constructed.Then,under the framework of adaptive control technology,a fuzzy adaptive controller is constructed combined with the fuzzy basis function.so that the USV swarm system can track the desired target and achieve global asymptotic consistency stability.Then,the effectiveness of the swarming decision-making mechanism and control method in this thesis is verified by simulation.Secondly,the problem of obstacle avoidance and tracking control for underactuated marie vehicles(UMV)swarming system with unknown external environmental disturbance is studied.By constructing artificial potential function,the UMV can avoid external static obstacles.A finite time lumped observer is designed to track and compensate the uncertain information,which can get rid of the dependence of the control accuracy on the precise mathematical model of the UMV.At the same time,a finite-time swarm motion control strategy is designed by combining the uncertain lumped observer and non-singular terminal sliding mode technology,which ensures the path tracking performance of the swarm,and the surge and heading tracking error of the UMV can converge to balance point.Simulation experiments verify the effectiveness and superiority of this design method.Finally,considering the path following control problem of the UMV swarming system under the failure of the thruster with uncertain disturbance of the ocean,a fault-tolerant tracking control strategy based on the fixed-time lumped observer is designed.The fixed-time observer can realize the observation and compensation of uncertain information within a small time upper bound.Combined with the integral sliding mode control method,the control accuracy and anti-interference ability of the system are effectively improved,and ensures the stability of the swarm system under fault constraints.Through the theoretical analysis of stability,it is ensured that the tracking error of the UMV converges to zero within a limited time.The simulation results show the stability of the swarming fault-tolerant control and the accuracy of the swarming tracking.