Surrounding Control Of Multi-agents On Non-cooperative Targets

With the development of science and technology,the collaborative control of multi-agent systems such as robots and UAV has been widely used to perform various tasks.For example,robot flocking,UAV formations,etc.,so many scholars have conducted extensive research on collaborative control of multi-agent systems.One of the basic cooperative control problems is the surrounding control problem.The surrounding control problem refers to designing a control law for surrounding agents so that multi-agents can achieve encirclement of the target.The research on the surrounding control problem has also formed a wealth of literature,but they all consider the situation where the target and the surrounding agent are cooperative,and the target will not respond to the surrounding agent.In some application scenarios,such as robot herding,UAV to drive bird flocks,etc.,the herd and bird flocks are all non-cooperative,which brings challenges to the realization of surrounding control.Therefore,this thesis aims at the surrounding control of non-cooperative targets by multi-agents,establishes a non-cooperative model based on the artificial potential field method,and studies the surrounding control of non-cooperative targets by multi-agents.The main tasks are as follows:First,in view of the existence of a single non-cooperative target in the surrounding control problem,based on the velocity field method,construct the velocity field around the desired trajectory as the target reference velocity.Design an arc-shaped formation surrounding control strategy,and obtain the desired position of the surrounding agent according to the ideal reference speed of the target and the interaction model between the surrounding agent and the target.A finite-time controller is designed for the surrounding agent,and under the action of the controller,the speed applied by the surrounding agent to the target is consistent with the target's reference speed.It is verified by simulation,and the simulation results show that the surrounding agent is distributed around the target in an arc shape under the action of the designed controller,and guides the target to move along the desired trajectory.Secondly,for the situation where there are multiple non-cooperative targets in the enclosing control problem,the method based on the geometric center estimator is used to obtain the estimated value of the center of the group target.A smooth finite-time geometric center estimator is designed,which eliminates the chattering caused by the traditional estimator,and proves its finite-time convergence.Analyzing the cluster behavior of non-cooperative target groups,constructing a flocking model of target groups.Using the geometric center estimator and the surrounding controller,the surrounding agent controls the surrounding of multiple non-cooperative targets.The simulation results show that the designed estimator eliminates the chattering phenomenon,and the surrounding agent realizes the arc-shaped surrounding and guiding multiple non-cooperative targets to move along the desired trajectory.Finally,consider the surrounding control problem when the surrounding agent and the noncooperative target have higher-order dynamics models.Analyze the flocking behavior of noncooperative target groups with second-order dynamics model,and build a flocking model of noncooperative target groups based on the Reynolds model.A new enclosing control strategy based on string nets is proposed,and the enclosing agent obtains the enclosing radius according to the target group radius estimator.The surrounding of the target is completed according to the surrounding radius and geometric center,and a chord network is formed between the surrounding agents to limit the movement of the target.The virtual structure method is used to keep the surrounding agent in formation to guide the target group.Simulation is used to verify the effectiveness of the enclosing control strategy,and the simulation results show that the non-cooperative target group eventually forms a cluster,and the surrounding agent encloses the target group and guides the target to the desired area.