Output Consensus Of Discrete-time Multi-agent Systems

In recent years,the cooperative control of multi-agent systems has already attracted quite a bit of attention because of its wide application in many fileds.The cooperative control means that the multi-agent systems reach coordinated motion only through local information interaction among neighbor agent.The consensus is the most typical form of cooperative control and its objective is to make the state variable of the systems tended to be same.In practice,there are many factors that affect the consensus of multi-agent system.Based on the points of the influence of external disturbance and the strain capacity when some agents lose efficacy,this thesis investigates the output consensus of the discrete-time system with input saturation under the external disturbance and the switching network,respectively.For the case with the external disturbances,we consider that the disturbance of followers generated by the leader.This thesis sdudies the consensus of multi-agent systems with the same disturbance under the directed communication network and with the different disturbance under the strongly connected and detailed balance communication network.The distributed consensus protocols are proposed by adopting the relative state information between neighbors and the low gain control strategy.We can prove that the leader can be tracked by all followers by utilizing graph theory,Lyapunov function,matrix theory and so on,that is the multi-agent systems can reach output consensus.For the case with the strain capacity when some agents lose efficacy,this thesis studies the consensus problem of the discrete-time systems with the switching networks connected all the time or the switching networks jointly connected.The distributed state feedback control algorithms are designed by using the modified algebraic Riccati equation and the low gain control strategy.We can prove that the multi-agent systems can achieve the output consensus under the proposed control algorithm by using the Lyapunov function matrix theory,linear matrix inequality and so on.Finally,some conclusions have been done for the whole research of this thesis.The future works on the consensus under the directed switching communication networks and the heterogeneous multi-agent systems with input saturation and external disturbances are presented.