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In this paper, the problem of tracking control of networked control systems with false data injection attacks is studied. A new terminal integral adaptive sliding mode control method is proposed. Firstly, the mathematical model of networked control system with the actuator and sensor false data injection attacks is modeled. Secondly, an augmented state observer is designed in order to estimate the augmented states, in which, a discontinuous input term is designed to defenses the actuator attack, and the convergence of the estimation error is proved. Thirdly, the tracking output errors are introduced to design the terminal integral sliding mode control method. Furthermore, in order to reduce the oscillation induced by the sensor false data injection attack, the terminal integral adaptive sliding mode control algorithm using the estimation error as adaptive factor is structured, and the stability of the algorithm are proved by using Lyapunov theory. Finally, a numerical simulation and a practical experiment are executed to verify the superiority of proposed control strategies.

With the widespread application of communication networks in industrial control systems , cyber-attacks bring a huge threat to the networked control system . In this paper, the issue of secure control of nonlinear jump networked systems with false data inject (FDI) attacks is investigated. In order to against the malicious attacks , a reduced-order-asynchronous sliding-mode control (SMC) strategy is proposed. Firstly, in order to damp the effect of nonlinear term and FDI attacks, an asynchronous sliding-mode function is designed, and the resultant sliding-mode dynamics is generated by using the reduced-order method. Then, the stability conditions for the reduced-order sliding-mode dynamics are given, and the sliding-mode parameters are solved by linear matrix inequality technology. Furthermore, the sliding-mode controllers are designed under the situation of the parameters is known or unknown, respectively, and the reachability of the sliding-mode motion is certificated. Finally, two examples are implemented to illustrate the potential of the presented control strategy.

This paper investigates the issue of tracking control of nonlinear system with external disturbance , an event-triggered fuzzy backstepping sliding-mode control strategy is proposed. Firstly, a fuzzy state estimator is designed to estimate the unmeasurable state, and a sliding-mode disturbance observer is presented on the estimation error. In which, consider the conservativeness of the observer parameter, a parameter adaptation law with a double nested structure is proposed to mitigate chattering problems caused by parameter conservativeness. Then an event-triggered mechanism along with backstepping control and sliding-mode strategy is designed to achieve tracking control and save the network resources, and the Zeno phenomenon can be avoided. Furthermore, the backstepping law combines with Lyapunov theory is used to prove that the tracking error can converge to a small bounded set and all the signals of closed-loop plant are bounded. Finally, simulation results are carried out to illustrate the potential of designed approaches.

This paper develops the secure control strategy design issue for jump cyber–physical systems (CPSs) with malicious attacks. In the jump CPSs, the jump signals are assumed to obey the semi-Markov distribution with the transition probability depends on the stochastic sojourn-time, the physical plant and actuator simultaneous subject to the adversarial attack. A secure control strategy on robust sliding-mode control (SMC) is designed to deal with the malicious attacks. Firstly, an integral sliding-mode hyperplane is constructed, and the sliding-mode dynamics is discussed. Then, the slide-mode parameters are solved by the linear matrix inequality method with prescribed H∞ damping index. Furthermore, a robust sliding-mode controller is presented, and the reachability of the sliding-mode motion is analyzed. Finally, two examples are implemented to prove the potential of the secure control approach.

This article is concerned with the load frequency control (LFC) for the multi-area power system (MAPS) in the presence of cyber-attacks and disturbances. A resilient model predictive control (RMPC) strategy combined with the mixed $H_{2} /H_{\infty } $ performance index and dynamic event-triggered mechanism (DETM) is developed by using the cone complementarity linearization algorithm and the linear matrix inequality technique. With the application of $H_{2} /H_{\infty } $ performance index, the resilience of the controlled MAPS is achieved and the cyber-attacks launched on the MAPS can be dealt with effectively. The goal of the DETM is to enhance the communication efficiency by interrupting the communication of the MAPS, the triggering condition of which utilizes the internal dynamic variable. Moreover, rigorous derivations on the recursive feasibility of the RMPC are given. Finally, a MAPS is given to illustrate the validity of the presented control strategy.

In this paper, a water injection cooling molding system is designed. Water injection cooling molding is an effective material molding method, which has a wide range of applications in the field of industrial production. The accurate control of water temperature is very important for the molding process, which can avoid a variety of defects, such as bubbles, deformation or gaps with the inner wall of the cavity. In order to further understand the influence of water temperature on the quality of molded products, the mathematical model is established according to the conservation of mass and energy, and analyze the influence of system parameters on the change of cooling temperature. The results show that the system input and parameter configuration have a great impact on the system performance and the final product quality. In order to obtain better molding quality, the system process parameters should be set reasonably. The model and research results in this paper play a certain reference role for the design of related systems, and lay a model foundation for the design of cooling water temperature control method.

In this paper, the model predictive control (MPC) problem is investigated for the cyber-physical system (CPS) with deception attacks. The proposed MPC takes the mixed H 2 / H ∞ performance index into consideration, by which the attacked system performance can be optimized and the robustness of the CPS can be satisfied. Besides, the cone complementarity linearization (CCL) method is introduced to address the non-convex issue and further the controller gains of the MPC are design. Moreover, the sufficient conditions that guarantee the recursive feasibility of the proposed MPC is demonstrated. Finally, the mass-spring-damping system is used to illustrate the validity of the presented control strategy.

This paper investigates the stability problem of event-triggered networked control for the positive linear systems. First, the proposed event-triggered mechanism (ETM) adopts the merits of the absolute and relative ETMs. Then, utilizing positivity of the positive linear systems, Lyapunov-Krasovskii functional is constructed to study the stability of the augmented system. Additionally, network induced delays and external disturbances that may deteriorate the performance of networked control systems (NCS) are considered. Furthermore, criteria for designing dynamic output feedback controller (DOFC) and ETM are derived. Consequently, a numerical example is utilized to show the effectiveness of the proposed method.

This paper studies the spectrum occupancy in the frequency between 87.5 MHz and 108 MHz allocated for radio broadcasting in China. Through analyzing spectral measurement results, we can be identified the “spectrum holes”, which provide the possible candidates for CR operations, a promising solution to alleviating the heavy pressure on the scarce radio spectrum. Furthermore, it also plays the guiding role when detecting the illegal radio broadcasting, attributing to maintaining the radio order. More specifically, we can be found the actual spectral usage in this band, which provide statistics for white spaces of the whole spectrum and obtain spectrum occupation time and ratio.