Observer-based event-triggered H∞control of networked switched systems under hybrid attacks

This article is concerned with the issue of observer-based event-triggered H-infinity control for networked switched systems (NSSs) under hybrid attacks. Since hybrid attacks can cause more damage to the system than a single cyber attack, this article considers a situation where stochastic deception attacks and aperiodic denial-of-service (DoS) attacks coexist in NSSs. To address this issue, the dynamics of the initial switched system combined with the event-triggered mechanism (ETM), observers and hybrid attacks are formulated as a new augmented switched system. Thereinto, the unmeasurable states are estimated by a newly constructed gain adjustable observer and an observer state-based adaptive ETM is designed under DoS attacks to save limited communication resources. Then, employing the Lyapunov stability theory and average dwell time (ADT) approach, sufficient conditions are obtained to guarantee the mean-square exponential stability with a H-infinity performance index of the new model. And the quantitative relationship between the switching signal and DoS attacks is formulated. Moreover, a co-design method of ETM parameters and observer-based controller gains is proposed. Compared with some existent results, restrictions on DoS attack signals and switching signals are relaxed. Finally, a numerical example is utilized to verify the feasibility and effectiveness of the proposed theory.