Secure Control for Cyber–Physical Systems Subject to Aperiodic DoS Attacks

This article addresses the secure control issue for cyber-physical systems (CPSs) under aperiodic denial-of-service (DoS) attacks. Malicious DoS attacks disrupt the communication between the controller and the actuator. The finite attack resources of malevolent attackers are taken into consideration, and the DoS attacks are characterized using an aperiodic model. In contrast to prior results, the present study tackles the issues of security analysis and secure controller design by considering the attributes of the DoS attacks, instead of employing a switched system approach to address the aforementioned concerns. First, under aperiodic DoS attacks, sufficient criteria are established to guarantee that the closed-loop CPSs can attain asymptotical stability. Second, within a time-varying attack period, the relationship between the attack active interval and the attack silent interval is derived, if this relation is not satisfied, the stability of the system will deteriorate. Finally, a unified framework is developed to address the external disturbances and aperiodic DoS attacks. Sufficient criteria are introduced for evaluating the security of CPSs, and a corresponding secure control scheme is also designed. To verify the efficacy of the derived theory, a wheeled mobile robot system under aperiodic DoS attacks is illustrated.