Addressed in this paper is the problem of observer-based periodic event-triggered (PET) adaptive fuzzy control for a class of nonlinear systems adopting a predictor approach. In most existing results on PET output- feedback control, only the system output at sampling instants is available for observer design. For the use of more effective information in observer, a predicted signal of the continuous system output is generated by a predictor and used for the construction of observer. Then, a dynamic gain is introduced to the construction of Lyapunov function to ensure the decreasing property of the developed Lyapunov function at sampling instants. Owing to this good property, the PET adaptive controller can be designed using adaptive fuzzy control and backstepping techniques. It is proved that the system states are locally bounded and converge to a small neighborhood of the origin under given sampling period and controller. Finally, two examples are provided to verify the effectiveness and advantage of the proposed control method.

In this paper, the problem of event-triggered prescribed-time output-feedback tracking control is discussed for a class of switched nonlinear systems with asynchronous switching. By using a modified time-dependent scale function and the barrier Lyapunov function technique, the output tracking error is constrained without the requirement of restricting its initial value. Then, a mode-dependent event-triggered mechanism is developed by using a logarithm-type relative threshold strategy, under which the effect of asynchronous switching caused by event triggering and system switching is reduced. Meantime, the excessively large control input is avoided without introducing the mixed threshold strategy. Subsequently, with the aid of the designed event-triggered controller, the output tracking error can converge to the preassigned tracking accuracy within a prescribed time. It is proved that the Zeno behavior does not happen. Finally, two examples are given to verify the effectiveness of the proposed control method.

This note studies the global event-triggered control problem for a class of switched nonlinear systems in the sense of output feedback by the average dwell-time method. Since system switching has no regularity and the controller is only updated at triggering instants, the mismatch behavior may happen between the controller and its corresponding subsystem, which may lead to a destroyed system performance. To derive a flexible triggering condition and solve this problem, two dynamic gains are introduced and a mode-dependent dynamic triggering mechanism is designed. Then, by using the weighted homogeneity and inequality techniques, a mode-dependent dynamic event-triggered controller is developed by output feedback, under which the system states can globally enter an adjusted neighborhood of the origin. Meantime, by the skillful use of the right-continuous property of the switching signal, the Zeno behavior is proved to be avoided. Finally, as the effectiveness verification, two practical examples are provided.

This note studies the issue of decentralized event-triggered control (ETC) for nonlinear cyber-physical systems (CPSs) under denial-of-service (DoS) attack by output feedback. Due to the existence of DoS attack, an attack signal dependent observer is designed to reconstruct the unknown system states. To save the communication resources, an ETC strategy is introduced. Since the triggering controller is only updated at triggering instants, it may not switch from normal (attack) mode to attack (normal) mode when the system works well or subjects to attack. This feature may lead to the mismatch behavior between triggering controller and corresponding sub-system and destroyed system performance. To solve this issue for nonlinear CPSs, a decentralized ETC scheme is given based on the feature of DoS attack. With the presented control scheme, a new decentralized event-triggered controller is designed through the idea of average dwell time, under which all closed-loop signals are bounded and the system states can converge to a bounded close set around the origin. Meantime, it is proved that the Zeno behavior is avoided successfully. Finally, as the effectiveness verification of the proposed control strategy, a practical example is provided.

This article studies the issue of adaptive event-triggered output-feedback control for switched p -normal nonlinear systems with the unknown homogeneous growth rate. A homogeneous output-feedback controller is first designed for nominal nonlinear systems based on adding one power integrator technique. Then, a dynamic gain technique is introduced to deal with the difficulty caused by the unknown homogeneous growth rate. With an elaborate design of the adaptive law of the dynamic gain, a novel adaptive event-triggered output-feedback controller is developed to ensure that the closed-loop system is globally asymptotically stable. Meanwhile, a new analysis way is proposed to prove that the Zeno behavior is excluded in the event-triggered control system. Finally, two examples are provided to indicate the effectiveness of the proposed control method.

This paper investigates the problem of dynamic event-triggered output feedback tracking control for a class of p-normal nonlinear systems with unknown growth rate. To cope with the unknown growth rate imposed on the system nonlinearities, a dynamic gain technique is introduced and a constructive coordinate transformation is given. On the other hand, an event-triggered strategy combining with the dynamic gain is proposed such that the triggering threshold can be adjusted in an adaptive manner. With the help of the proposed event-triggered strategy, a dynamic event-based output feedback controller is developed to ensure that all signals of the closed-loop system are bounded while the tracking error converges to a small neighborhood of the origin. Moreover, it is proved that the Zeno behavior is excluded in the presence of nonsmooth controller. Two examples, including an induction heater circuit system and a numerical example, are provided to indicate the effectiveness of the proposed control method.

This note considers the issue of global asymptotic stabilization for a class of nonlinear systems with unknown time-varying delays and control gain using a dynamic event-triggered (DET) output feedback scheme. In the context of unknown time-varying delays and control gain, nonsmooth control law and some extra redundant terms will be encountered in the design of DET controller, which would bring substantial challenges to the achievement of event-triggered stabilization. Specifically, two dynamic gains and a modified Lyapunov-Krasovskii functional are first presented, which makes the effects of time-varying delays and control gain be conquered. Then, a DET mechanism utilizing the dynamic gain is given to reduce the amounts of event transmissions and dynamically compensate the triggering error. By virtue of the designed strategy, a new DET output feedback controller is developed, which renders the closed-loop system globally asymptotically stable. Meanwhile, it is proved that the Zeno behavior does not happen. Finally, in order to demonstrate the feasibility of the proposed scheme, corresponding examples are provided.