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In this article, the dynamic output‐feedback H∞ control problem is investigated for discrete‐time state‐delay systems subject to exogenous disturbances and actuator saturations under the round‐robin communication protocol. Using the switched system approach, the Lyapunov–Krasovskii functional and the modified sector condition, sufficient conditions are first obtained under which the closed‐loop systems can achieve some desirable performance indices such as the boundedness, the H∞ performance and the stability in the absence of disturbances. Then, the controller is explicitly characterized by means of the solvability of linear matrix inequalities. For the case without time delays, the corresponding conditions are also presented. Subsequently, the optimization problems about the performance indices are discussed. Finally, the benefit and effectiveness of the proposed results are specifically illustrated via two simulation examples. [ABSTRACT FROM AUTHOR]

This study investigatesthe neural‐network (NN)‐based adaptive decentralised controller design issue for a class of large‐scale non‐linear non‐strict‐feedback interconnected systems with time‐varying asymmetric output constraints and dead‐zone inputs. The existences of the non‐strict‐feedback structure, time‐varying asymmetric output constraints, and dead‐zone inputs lead to the construction of the controller of each subsystem is very difficult. By applying the inherent property of Gaussian functions employed in radical basis function NNs, the non‐strict‐feedback structure is skillfully handled, and the adaptive backstepping method is used to construct the desired controllers of all subsystems. Furthermore, Lyapunov stability analysis shows that all the signals of the closed‐loop system are ultimately bounded, and each subsystem output can converge to an arbitrarily small and predefined time‐varying range with the corresponding constraint is always satisfied by employing a barrier Lyapunov function. Finally, simulation results based on a practical example prove the effectiveness of the proposed design strategy. [ABSTRACT FROM AUTHOR]

In this study, the boundedness and the input‐to‐state stabilisation problems are investigated for a kind of switched delayed differential systems with exogenous disturbances. To reduce the communication burden, an event‐triggered strategy is adopted in the feedback control loop to stabilise the addressed switched delayed differential systems. The notions of boundedness and input‐to‐state practical stability are employed to characterise the control objectives in the presence of exogenous disturbances, switching signals and event‐triggered schemes. Some upper bounds on the system states are obtained and the Zeno phenomenon is shown to be excluded under the proposed event‐triggered scheme. The gain of the feedback controller, the parameters of the event‐triggering function and the switching signals are jointly designed for the underlying delayed differential systems. At last, a numerical example is exploited to given to demonstrate the effectiveness of the authors' developed control scheme. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the dynamic self‐triggered output‐feedback control problem is investigated for a class of nonlinear stochastic systems with time delays. To reduce the network resource consumption, the dynamic event‐triggered mechanism is implemented in the sensor‐to‐controller channel. Criteria are first established for the closed‐loop system to be stochastically input‐to‐state stable under the event‐triggered mechanism. Furthermore, sufficient conditions are given under which the closed‐loop system with dynamic event‐triggered mechanism is almost surely stable, and the output‐feedback controller as well as the dynamic event‐triggered mechanism are co‐designed. Moreover, a dynamic self‐triggered mechanism is proposed such that the nonlinear stochastic system with the designed output‐feedback controller is stochastically input‐to‐state stable and the Zeno phenomenon is excluded. Finally, a numerical example is provided to illustrate the effectiveness of proposed dynamic self‐triggered output‐feedback control scheme. [ABSTRACT FROM AUTHOR]

This study is concerned with the event‐based security control problem for a class of discrete‐time stochastic systems with multiplicative noises subject to both randomly occurring denial‐of‐service (DoS) attacks and randomly occurring deception attacks. An event‐triggered mechanism is adopted with hope to reduce the communication burden, where the measurement signal is transmitted only when a certain triggering condition is violated. A novel attack model is proposed to reflect the randomly occurring behaviours of the DoS attacks as well as the deception attacks within a unified framework via two sets of Bernoulli distributed white sequences with known conditional probabilities. A new concept of mean‐square security domain is put forward to quantify the security degree. The authors aim to design an output feedback controller such that the closed‐loop system achieves the desired security. By using the stochastic analysis techniques, some sufficient conditions are established to guarantee the desired security requirement and the control gain is obtained by solving some linear matrix inequalities with non‐linear constraints. A simulation example is utilised to illustrate the usefulness of the proposed controller design scheme. [ABSTRACT FROM AUTHOR]