Distributed Secure Coordination Control Of Multi-Agent Systems Under Cyber Attacks

The cooperative control of multi-agent systems(MASs)aims to design control protocols for each agent belonging to a MAS,such that they can cooperatively complete a complex task,such as multi-robot formation,mechanical structure synchronization,distributed sensor information fusion,etc.Since information is transmitted between agents through a shared network,the openness of the communication network exposes the stability of the MASs to the threats of various cyber attacks.While the secure control problem of networked Lagrangian systems,which are widely used to model practical systems,has not received extensive attention.To fill the mentioned gaps,the secure strategies are designed for MASs based on the characteristics of different cyber attacks in this paper,and the MASs modeled by Lagrangian dynamics with uncertain parameters are considered.The main work of this paper is as follows:Firstly,a secure control protocol is proposed under the event-triggered communication framework for the secure consensus control problem of the MASs under synchronous DoS attacks.According to the characteristics that synchronous DoS attacks can block the information interactions of the entire system,this paper designs switching event-triggered communication strategies and switching controllers by combining the model reference adaptive control technology and event-triggered communication technology.By using the proposed strategy,the secure consensus control of the MASs under DoS attacks can be achieved even if some parameters are difficult to be obtained.Subsequently,the stability of the control system is proved by using the Lyapunov stability theory,and the upper bound of the DoS attacks that can be tolerant is given.Secondly,for the secure consensus control problem of MASs under asynchronous DoS attacks,independent event-triggered secure control protocols are designed for each communication link.According to the characteristics that asynchronous DoS attacks can only affect part of the communication links,this paper distinguishes the normal communication links from those attacked and designs switching event-triggered communication strategies and switching controllers for each communication link.By using the proposed strategy,the secure consensus control of the MASs with uncertain parameters under asynchronous DoS attacks can be achieved.Then,by using the Lyapunov stability theory,the upper bound of the DoS attacks that can be tolerated on each communication link is given.Finally,for the secure consensus control problem of the MASs subject to Byzantine attacks,a norm-based resilient decision algorithm is proposed to exclude the impact of Byzantine agents on the system.According to the behavior pattern of Byzantine agents,analyzing from the perspective of graph robustness,the proposed algorithm excludes the impact of Byzantine agents by deleting unreliable edges with sufficient robust communication topology.After using the proposed algorithm,the achievement of the secure consensus control objectives under Byzantine attacks can be guaranteed by a fully distributed controller.Then,the upper limit of the number of Byzantine agents that the algorithm can tolerant is given,and the theoretical analysis is carried out by taking the MASs with uncertain parameters.