Research On Formation Control Of Multi-Agent Systems

In recent years, the distributed formation control of multi-agent systems has been attracted a considerable interest in various scientific communities among researchers due to broad applications in social, industrial and national defense areas, et al., such as unmanned air vehicles formation control, multiple robots formation control, and so on. The so-called formation control problems are a kind of control technology, which means in the course of reaching the destination; the multiple agents hold a specific formation pattern as well being adapted to the environmental constraints. During the process of cooperation, the design of proper distributed pursuit strategies has been the crucial factor to achieve global collaborated behavior.In this thesis based on the algebraic graph theory, BIBO (Bounded Input Bounded Output) stability theory, et al., as well as adopted the methods of combining theoretical analysis and numerical simulation, leader-following formation control problems of multiple agents with both single-integrator kinematics and double-integrator dynamics are investigated, the specific main research contents and achievements include several aspects as follows.Firstly, distributed formation control of a large number of agents with continuous single-integrator kinematics on directed acyclic graphs is investigated. Considering both cases of zero transmission time-delays and constant transmission time-delays in velocity, the distributed pursuit strategies are designed to make all agents achieve a collective motion while holding a formation pattern. During the motion, leaders perform collective motion with the uniform velocity or the time-varying velocity in a predefined formation and followers can access the relative positions of their neighbors and the leaders’velocity. By using the stability theory, the necessary and sufficient conditions that the systems satisfy are given respectively to ensure the effectiveness of the distributed pursuit strategies.Secondly, based on the theoretical research of single-integrator kinematics, we continue the research on distributed formation control of double-integrator dynamics. Without considering any transmission time-delays, the distributed formation control protocols are designed to make multi-agent systems achieve a stable and desired formation. By using signal flow graphs and Mason’s rule, necessary and sufficient conditions are derived to meet BIBO stability for the pursuit systems.Finally, aiming at the formation control of continuous both single-integrator kinematics and double-integrator dynamics, we configurate the control parameters according to necessary and sufficient conditions, consequently finishing the numerical simulation. The simulation results indicate that under the distributed pursuit strategies we design, the multi-agent systems can achieve stable and desired formation pattern, thereby proving the feasibility and effectiveness of the pursuit strategies.