Active Fault-Tolerant Predictive Control Methods For Networked Multi-Agent Systems

In recent years,the research heat of networked multi-agent systems(NMASs)in the control field has continued to rise.The NMASs are distributed autonomous systems composed of multiple agents that can interact through the network.Each agent in the system can be used as a subsystem.Compared with single agent and networked control systems,multi-agent systems(MASs)can interact with the environment and have certain information processing capabilities and the ability to solve complex problems,so it is widely used in many practical scenarios.How to effectively deal with the random network delay or data packet dropout in the system is crucial to the stability of the system.During the execution of the task,the internal physical components of the agent,such as actuator or sensor,may occur in fault due to the long-term operation of the device and the interference of the external environment.In particular,when the actuator fault or sensor fault of an agent in the system appear,the fault information will quickly spread to the whole system through the communication network,thus affecting the output tracking control effect of each agent in the system and even threatening the security of the agent and the system.In this paper,a class of linear discrete NMASs is selected as the controlled object.For the case where there are only actuator faults and random communication constraints and the case where there are both actuator and sensor faults and random communication constraints,different state observers and corresponding control law are designed to realize the output tracking control of NMASs.The main work of this paper is divided into the following three aspects:(1)An active fault-tolerant control method based on state observer is designed for MASs with ideal communication conditions.Under ideal conditions without considering the influence of communication constraints,active compensation for actuator and sensor faults can be achieved,and the adverse effects of actuator and sensor faults on the system can be reduced.The effectiveness of the designed control method is verified by numerical simulation.(2)The output tracking control problem of NMASs with actuator faults and two-channel random communication constraints is studied.Combining active fault-tolerant control and networked predictive control,an active fault-tolerant predictive control method for NMASs is proposed.It can effectively reduce the adverse effects of actuator faults and random communication constraints.The necessary and sufficient condition for the stability of the closed-loop system is derived.Numerical simulation and experimental result verify the effectiveness and feasibility of the method.(3)The NMASs with two-channel random communication constraints,actuator and sensor faults are studied.A cloud-based active fault-tolerant predictive control method for NMASs is proposed to realize the output tracking control of system.First,the observer is designed to estimate the agent state,actuator and sensor faults.Thus,the fault-tolerant predictive controller is configured in the cloud node to predict the future state of the agent and output the control prediction sequence.The delay compensator compensates the random network delays by receiving the control prediction sequence.Finally,the effectiveness of the method is verified by theoretical analysis and numerical simulation results.