Switched-type unknown input observer-based fault-tolerant control for cyber-physical systems in the presence of denial of service attack

Abstract

The problem of security control for cyber-physical systems (CPSs) is gradually becoming a popular research topic. In the presence of the denial-of-service (DoS) attack, this paper investigates the switched-type unknown input observer-based fault-tolerant control problem for multi-channel CPSs. Firstly, based on the sampling mechanism, a switched-type unknown input observer (SUIO) which can discard the outdated information is designed to obtain state/fault estimations, and converting the estimation error system stability analysis under DoS attack into that under SUIO. Then, to compensate the effect of actuator fault, an SUIO-based fault-tolerant controller is designed. And the input-to-state stability of the CPSs is analyzed. In comparison with the existing UIO studies, this paper considers the case of DoS attack affecting the transmission channel, and the impact of DoS attack on estimation effect can be effectively reduced by introducing the switching mechanism. Finally, based on the simulation results of the given experiments, the effectiveness of the proposed method is illustrated.