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This paper aims to establish a novel adaptive event-triggered scheme of global output-feedback stabilization for nonlinear systems with unmeasurable state dependent growth under the architecture with network communication among sensor, observer-based controller and actuator. To suppress the inherent system nonlinearities (reflected by the polynomial-of-output growth rate), a dynamic gain is integrated into event-triggered scheme. While reducing execution as much as possible to maintain efficiency, it is critical to ensure timely information transmission and control updating for the effectiveness of adaptive mechanism. To this end, double-side asynchronous adaptive event-triggering mechanisms, instead of a one-side or (double-side) synchronous one, are delicately designed by fully exploiting the dynamic gain, upon which adaptive event-triggered output-feedback control is established to ensure the system states to converge to zero. Particularly, the time of evaluation suspension and the threshold parameter for the events on system output and observer states are not fixed but rather online adjusted with the alteration of dynamic gain, to make sure to counteract the influence of sampling/actuation error. Unlike the related results, the adaptive event-triggering mechanisms render the inter-execution times determined purely according to system behavior and without explicit upper-bound limit, which retain the desired potential in execution reducing. [ABSTRACT FROM AUTHOR]

This paper addresses the event-triggered output-feedback stabilization for a class of uncertain nonlinear systems. Essentially different from the related literature, the systems under investigation allow large uncertainties (whose size is unknown) coupling to unmeasurable states, which requires to integrate a comprehensive output-feedback compensation mechanism into the event-triggered philosophy and would bring substantial challenges to the event-triggered control. To solve the problem, a novel scheme of adaptive event-triggered output-feedback control is established for the systems. Specifically, an adaptive dynamic gain is introduced not only to counteract the large uncertainties but also to cope with the execution/sampling error. Then, an adaptive event-triggered output-feedback controller based on dynamic-gain observer is constructed to guarantee global convergence for the resulting closed-loop system while reducing execution/sampling. Particularly, the event-triggering mechanism involved is delicately designed by fully exploiting the dynamic gain, to enable the negative influence of the gain through the execution error to be counteracted (no matter how large the gain becomes) while precluding infinitely fast execution which violates the implementation of event-triggered controller in practice. Correspondingly, a distinctive analysis pattern is implemented for the closed-loop performance, due to the coupling of the dynamic-gain compensation mechanism and the event-triggering mechanism. Moreover, for more efficient resource saving, we further show the feasibility of adaptive dynamic event-triggering mechanism for the desired stabilization. [ABSTRACT FROM AUTHOR]

This paper investigates the event-triggered stabilization for a class of uncertain nonlinear systems. Remarkably, the systems allow not only inherent nonlinearities but also the large uncertainties (whose size is unknown). The two ingredients together really challenge the event-triggered control design, partly because for the latter, certain compensation mechanism is necessary but hard to incorporate in the nonlinear event-triggered paradigm. To solve the problem, a new switching event-triggered control scheme is proposed in this paper by incorporating a logic-based switching mechanism which can instantly adjust controller parameter/structure and hence has strong adaptive capability to large uncertainties. The key point of the scheme is how to flexibly couple the event-triggering mechanism and the switching varying mechanism, determining not only when to sample/execute but also when to switch the design parameter, such that the switching event-triggered controller can effectively dominate/counteract the nonlinearities, the uncertainties and the sampling error, and thus can achieve the global stabilization of the systems. Owing to the introduction of switching varying mechanism, the performance analysis of the closed-loop system is a bit complicated, especially showing the nonoccurrence of infinite switchings or infinitely fast sampling/execution. Extended investigations are particularly performed for the switching event-triggered controller for its reliable implementability and broad application: By strengthening the switching varying and event-triggering mechanisms, the modified controller can additionally guarantee the pre-evaluation of sampling/execution rate and the tolerance to more types of disturbances, respectively. A simulation example on controlled Chua's circuit demonstrates the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]