Research On Sliding-Mode Fault-Tolerant Consensus Control For Multi-Agent Systems With Actuator Faults

Consensus control of multi-agent system is a fundamental problem in cooperative control.The existence of the actuator fault,external disturbances and other factors in the system have influenced the consensus control performance of multi-agent system,which makes the research on fault-tolerant control of multi-agent system very meaningful.This paper studies the fault-tolerant consensus control of multi-agent systems with actuator faults,unknown leader state,nonnegative or sign network topology in fixed-time and predefinedtime.The main research contents of the paper are as follows:Firstly,under a nonnegative undirected communication network topology,aiming at a second-order nonlinear multi-agent system with the problems of that leader’s states are unavailable to partial followers and some followers have actuator faults,a fixed-time sliding mode fault-tolerant consensus control algorithm is proposed based on a leader fixed-time state observer.The leader fixed-time state observer is designed to estimate the states information of the leader,then the observed leader’s information combined with the sliding mode control method is used to design a fixed-time fault-tolerant controller.The Lyapunov stability theory analysis and simulation results show that the designed fault-tolerant control strategy can make the multi-agent system realize the leader-follower consensus control within a fixed-time under the condition that the leader’s states are not accessible to partial followers and some followers have actuator faults.Secondly,under a signed communication network topology,a fixed-time sliding mode fault-tolerant bipartite control algorithm based on leader fixed-time cascade state observer is proposed for second-order nonlinear leader-follower multi-agent system with the problems of that the leader’s speed information is unmeasurable and some followers have actuator faults.A leader fixed-time cascade state observer is designed to reconstruct the leader’s state information,then a fixed-time fault-tolerant bipartite consensus controller is proposed based on the integral nonsingular fast terminal sliding mode surface.The Lyapunov stability theory analysis and simulation results show that the designed faulttolerant control strategy can enable the followers in the multi-agent system to track the leader’s trajectory within a fixed-time even under the condition of individual actuator fault.Finally,under a signed communication network topology,a predefined-time faulttolerant bipartite consensus control algorithm based on TBG(Time Base Generation,abbreviated as TBG,actually a time generation function)is proposed for both second-order nonlinear leader-follower multi-agent system and leaderless multi-agent system with the problems of cooperation-adversary and actuator faults.The mathematical properties of TBG are used to construct the error auxiliary variables,then the predefined-time fault-tolerant bipartite consensus controller is designed based on the sliding mode surface composed of the error auxiliary variables.The Lyapunov stability theory analysis and simulation results show that the fault-tolerant control strategy designed for leader-follower multi-agent system and leaderless multi-agent system can realize the predefined-time bipartite consensus control.