Distributed Fault Estimation And Formation Control Of Multi-agent Systems And Its Application

With the rapid development of society and the advancement of technology,many things that were previously unthinkable have now become reality,such as: robot formation dancing,drone formation performances,etc.These are the control problems of multi-agent systems developed by relying on network technology and computer technology.Multi-agent systems are widely used in social production and life,ranging from drone performances that are encountered daily to deep space exploration carried out by satellite formations.If any one of the subsystems in the multi-agent system fails,the entire system may face huge damages through the spread of the network.Therefore,this paper takes the formation fault-tolerant control of multi-agent systems as the research direction,and further introduces ideas of multi-agent formation fault-tolerant control into the problem of satellite formation flying control.The main research points of this article are as follows:Aiming at the second-order linear multi-agent systems with actuator bias fault,unmatched uncertainty and external disturbance,an integrated formation fault-tolerant control method based on fault estimation observer is proposed.Considering that if the fault estimation of the multi-agent systems is directly performed,the mutual coupling phenomenon between multiple subsystems may cause the actuator bias fault estimation of each subsystem to be inaccurate.In response to the above problems,the multi-agent systems is decoupled into multiple independent observable virtual subsystems by introducing spectral decomposition and coordinate transformation methods,and on this basis,an UIO is designed to accurately estimate the virtual actuator bias fault,then obtain the fault estimation value of the real subsystem through fault reconstruction.Using the output information of the observer and sliding mode control technology to design the formation fault-tolerant controller.After completing the theoretical proof through the Lyapunov,two sets of comparative simulations are given to demonstrate the superiority of the proposed formation fault-tolerant control algorithm.Aiming at the satellite formation flying system with external disturbance and actuator misalignment,an adaptive formation control method based on neural network is proposed.Before designing the formation control algorithm,the model of satellites are skillfully converted into Lagrange second-order models,which greatly simplifies the structure of the formation controller.Based on the Lagrange model,a non-singular terminal sliding mode controller is designed,and the output information of the neural network is added to the controller,so that the formation controller can compensate for external disturbance in real time and the good tolerance of the actuator misalignment,ensuring the attitude control of the satellite formation flying system.After completing the theoretical proof through the Lyapunov,two sets of comparative simulations are given to demonstrate the superiority of the proposed formation control algorithm.Aiming at the satellite formation flying system with actuator loss of efficiency fault,actuator misalignment and external disturbance,a distributed formation fault-tolerant controller design based on the loss of efficiency fault estimation observer is proposed.The design of the formation faulttolerant method is divided into two parts.The first part is to design a decentralized sliding mode observer for the satellite formation systems.The sliding mode term in the observer effectively suppresses the influence of external disturbance and actuator misalignment.The second part is to design an adaptive non-singular fast terminal sliding mode controller based on sliding mode technology,and then compensate the efficiency loss factor estimated by the observer to the controller in real time to ensure that when the actuator efficiency loss failure occurs,the controller can ensure the normal formation flying attitude of the satellites.After completing the theoretical proof through the Lyapunov,two sets of comparative simulations are given to demonstrate the superiority of the proposed formation fault-tolerant control algorithm.