Switching event-triggered control for a class of uncertain nonlinear systems

Abstract

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.