In this paper, we investigate the stability analysis and controller synthesis problems for a class of stochastic networked control systems under aperiodic denial-of-service (DoS) jamming attacks. First, an observer is constructed to estimate the unmeasurable states, and then a new adaptive event-triggered mechanism on the basis of the observer is proposed to eliminate the adverse effects of DoS attacks and schedule the transmission instants so as to realize a reduction of transmission burden in the network. Under the proposed event-driven communication scheme, an observer-based controller is designed, and a new switched system with time-varying delays is introduced. Conditions for the underlying systems to be mean-square exponentially stable with a weighted L2-gain are established. Also, conditions to co-design the observer, the controller, and the event-triggered scheme are developed. A mass spring-damper mechanical system is used as an example to demonstrate the effectiveness and advantages of the new design techniques.

In this paper, the resilient controller design and synthesis issues of networked control systems under denial-of-service (DoS) attacks are investigated via an adaptive event-triggered strategy. In a networked control system, DoS attacks have serious impacts on the security of communication, possibly causing degraded stability performance of the system. To remove threats from DoS attacks, an adaptive event-triggered communication mechanism is proposed, which also provides benefits in reducing the consumption of communication resources and relieving the pressure on network bandwidth. Since the system state information is usually not fully known, an observer-based controller is developed to stabilize the system and maintain a desired performance index despite the occurrence of stochastic attacks. Furthermore, a joint design method is proposed to obtain the controller gain, observer gain and event-triggered weight matrix. Finally, practical examples based on a four-tank system, an Internet-based three-tank system and an Internet-based test rig system are presented to illustrate the effectiveness of the proposed techniques to respond and eliminate the impact of DoS attacks.

This article addresses the event-triggered tracking control and filtering problem for Takagi–Sugeno fuzzy-approximation-based discrete-time nonlinear networked systems subject to the effect of denial-of-service attacks. First, the unreliability of the communication channel between the sensor and the actuator/filter is considered, and the packet loss caused by denial-of-service attacks is characterized by the binary Markov chain. Second, two novel resilient adaptive event-triggered mechanisms are proposed to resist the impact of denial-of-service attacks and discard unnecessary data packets, in which the dynamic threshold variable is designed to adjust the event-triggered condition adaptively. A problem caused by the event-triggered mechanism is that the controller or filter cannot receive the system mode signal during the trigger interval. To surmount this problem, this article designs an estimator to compensate for the unavailable system mode. Then, an adaptive event-triggered controller or filter related to the estimated mode is designed to track the desired signal. Under this framework, by constructing a membership-function-dependent Lyapunov function, the conservativeness of the stability criterion is relaxed. Finally, two examples are used to validate the applicability of the proposed approaches.

This paper investigates the issue of global robust H∞ pinning synchronization for a class of complex networks with sampled-data-based event-triggered communication via a pinning control approach. The complex network is subject to network-induced time-varying delays, parametric uncertainties and external disturbances. A directed and weighted communication topology is taken into account, and the phenomenon of uncertainties is reflected in both modelling and inner coupling matrices. In order to save communication resources, a new and practical event-triggered communication mechanism with an asynchronous sampling manner is developed, with which the Zeno behaviour can be absolutely avoided. Then, based on the presented event-triggered strategy, a pinning control protocol is proposed to reduce the frequency of controller updates and the computational burden. The problems on the minimal number and which of the nodes should be chosen are addressed. By Lyapunov stability theory, sufficient conditions are deduced to ensure the underlying network achieves global robust H∞ pinning synchronization. Finally, numerical examples are provided to verify the effectiveness of the new design techniques.

This article addresses the issues of exponential stabilization and $L_2$ -gain analysis for networked cascade control systems with aperiodic denial-of-service (DoS) jamming attacks, time delay, actuator saturation, and external disturbances. A resilient event-triggered communication mechanism based on the adaptive threshold technique is proposed to reduce transmission frequency and combat aperiodic DoS attacks. An event-driven cascade control strategy is developed to schedule control process updates and strengthen resistance to DoS attacks. Then, the system is modeled as a switched system closely related to the bounds of DoS frequency and duration. By using Lyapunov stability theory, conditions for the resultant system to be exponentially stable with a desired $L_2$ -gain performance level are established. A solution to the joint-design problem of controller gains and event-triggered parameters is also provided. A gas-turbine system of a power plant is employed to illustrate the effectiveness of the proposed approach.