Second-order Consensus Of Multi-agent Systems With Nonlinear Dynamics

The consensus problem of multi-agent systems which has been intensive research nowadays is an important research subject in complexity science, network science, con-trol science, and life science. Consensus, a group of agents in system, using local infor-mation exchange between each other, reach agreement on some certain states or goals for a while. In multi-agent systems, all the agents should be depended on second-order dynamic behavior with the position and velocity states, so that recently the second-order consensus has been paid more and more attention. In facts, in many practical multi-agent systems, every agent has its own time varying velocity, even be nonlinear. Meanwhile, complex networks with the "small world" and "scale free" properties have gradually become the hot spot of network science, one of the most basic subjects is identification the structures of complex networks.The thesis has deeply research the second-order consensus problem of multi-agent systems with time varying velocities, that is, second-order consensus of multi-agent systems with nonlinear dynamics. In second-order consensus, it is a crucial problem that how to determine the suitable coupling strengths of the position state and the velocity state, respectively. Further, finite time identification the structure of complex networks has also been discussed.The contents of this thesis are divided into five chapters. The background of multi-agent systems and some basic knowledge of complex networks and nonlinear dynamical systems are introduced in Chapter1. The main research work are show in Chapter2-4. Chapter5is the summary and prospect of this thesis. The main research work in this thesis are as follows:1. This chapter discuss the second-order consensus problem of multi-agent systems with nonlinear dynamics and time delay. In multi-agent systems, each agent not only should receive information from neighbor, but also have its intrinsic velocity dynamics. Moreover, in fact, the velocity information among agents are more difficult to obtain compared with the position information, a simple method that controlling the coupling gain of information exchange of velocity is proposed to solve this case. Further, the case that time delay between the information exchange of velocity is also considered. The method that inputting the virtual velocity signal is taken to get second-order consensus.2.This chapter has further discussed the second-order consensus problem of multi-agent systems with nonlinear dynamics via impulsive control. The situation that not being able to exchange the velocity information continuously may occur in multi-agent systems, in addition, the dynamics of velocity of each agent is usually nonlinear. The impulsive virtual signal which became from any agent of multi-agent systems or out-side random signal is designed for discussing the second-order consensus of multi-agent systems in fixed networks and switching networks, respectively.3. This chapter discuss the problem of structure identification in finite time of complex networks with coupling delay and stochastic perturbation. The structure of networks is a fundamental character in complex networks, one of the problem that must be solved is identification the structures of networks. Time delay and stochastic per-turbation which often actually exists in real network will effect identification of the structures of networks. On the other hand, we need identify the structure of networks within a certain time. Base on the above discuss, we proposed the method of identifica-tion in finite time to solve the problem of structure identification of complex networks with coupling delay and stochastic perturbation.