Observer-based Multi-agent Systems Include Control Studies

The containment control for multi-agent systems has engaged the attention of many academicians over the years,owing to the widespread application in aviation,industry,transportation,and so on.The containment control problems of multi-agent systems can be regarded as a special case of consensus and formation problems,which refers to the design of a distributed controller to drive the followers' motion trajectories to converge to the convex hull composed of leaders.Compared with the traditional problems of multi-agent systems,the containment control can highlight the more advantages of distributed cooperative control.Aiming at some situations that the convergence speed of the systems,the unknowable state of the agent and the time delays,external interference and network attack,this thesis investigates containment control problems of multi-agent systems based on observers.The concrete research contents are as follows:(1)The problems of finite-time containment control for multi-agent systems based on state observer are considered.For multi-agent systems with heterogeneous followers dynamics,combined with homogeneous theory and modern control theory,the finite-time containmenttracking control problem is studied.Moreover,when the motion state of the agent cannot be obtained online,for multi-agent systems with general linear dynamics,a finite time state observer and control algorithm based on output information have been put forward.By applying linear matrix inequalities(LMIs)and Lyapunov function theory,the sufficient conditions for finite-time containment control of multi-agent systems are derived.Finally,simulation examples are given to illustrate effectiveness of the proposed algorithms.(2)The problems of finite-time containment control for multi-agent systems based on disturbance observer are considered.For the second-order multi-agent systems with nonlinear dynamics and uncertain disturbances,a control algorithm based on fast terminal sliding mode control(FSMC)is proposed,and the finite-time containment control for the systems is realized by constraint disturbances.Furthermore,considering the inherent nonlinear dynamics of the system,a nonlinear finite-time disturbance observer is designed to estimate the unknown disturbance in the system,and a compound fast terminal sliding mode control algorithm based on the disturbance observer is given.Finally,simulation examples are provided to show the proposed control algorithms.(3)The problems of H_? containment control for heterogeneous multi-agent systems with time delays under denial-of-service(Do S)attack are considered.For the discrete-time multi-agent system under the directed sign network,considering that the agents cannot communicate normally under the interference of the attack,a distributed state observer is constructed to compensate for the denial-of-service attack on the system.In the controller design of each follower,a distributed dynamic state feedback control scheme is adopted to strengthen the constraint conditions of containment control through internal and external systems,enables the followers in the system to track the leader,and solve the problem of system output regulation.By using the knowledge of piecewise Lyapunov functional,graph theory,linear matrix inequality techniques,sufficient conditions for the asymptotic convergence of the system are obtained to ensure the stability of the system.Finally,numerical simulations verify the validity of the proposed theoretical results.