Research On Behavioral Fusion Formation Method In Escorting Missions For Swarms Of Unmanned Surface Vehicles

In 2020,195 incidents of piracy and armed robbery occurred worldwide,compared to 2019,an increase of more than 20%.since 2008,in order to protect the safety of Chinese ships and personnel sailing in waters with frequent piracy activities,the Chinese Navy has sent 36 ship formations to carry out escorting missions,escorting more than 6,800 Chinese and foreign ships.However,the human and financial resources spent on this is also huge.Compared with conventional ship formations,swarms of unmanned surface vehicles performing escorting formation missions can greatly save operational costs and reduce personnel casualties.In this paper,we take swarms of unmanned surface vehicles for escorting mission as the research object,discuss the cooperative formation method of swarms of unmanned surface vehicles for the formation rendezvous stage,formation maneuvering stage and formation reconfiguration stage of escorting mission,and carry out semi-physical simulation experimental research.First,the semi-physical simulation verification platform is built according to the swarms of unmanned surface vehicles test scenario.The system composition of the semi-physical simulation verification platform,the software functions of the subsystems and the working principle of the semi-physical simulation verification platform are introduced to lay the foundation for the subsequent simulation tests.Then,for the formation rendezvous problem of swarms of unmanned surface vehicles escorting,the mathematical model of formation rendezvous problem is analyzed,and the formation rendezvous method based on distance information is designed to solve the problems of inflexible rendezvous strategy and low efficiency of the formation rendezvous method based on location information.Through Lyapunov theory,the stability of the system is analyzed.We design the simulation test of formation mustering under the same initial state and compare it with the virtual structure method(based on distance)to verify the superiority of the method.We design the formation rendezvous simulation test under different initial states to verify the feasibility of the algorithm.Secondly,for the formation maneuvering problem of swarms of unmanned surface vehicles escorting,we analyze the behavior composition of formation maneuvering stage,introduce zero space as fusion idea,design behavior function,improve behavior fusion strategy,and solve the problems of formation lag and trajectory oscillation existing in traditional zero space behavior fusion algorithm.Through Lyapunov theory,the stability of the system is analyzed.Two kinds of formation maneuvers simulation tests are designed for escorting target variable heading and swarms of unmanned surface vehicles obstacle avoidance to compare with the traditional null-space behavior fusion algorithm and verify the feasibility and superiority of the method.Finally,for the formation reconfiguration problem of swarms of unmanned surface vehicles escorting,the formation reconfiguration method is explored by considering the change of the number of members.According to the different off-boarding members,different formation libraries are designed to solve the formation reconfiguration formation selection problem.We introduce event triggering mechanism and design event triggering function to solve the problems of premature formation reconfiguration and lengthy formation reconfiguration process.We design the simulation test of formation reconfiguration with changing number of members to verify the feasibility of the method.We design the formation simulation test for the whole stage of swarms of unmanned surface vehicles escorting to verify the effectiveness of the algorithm.