Event‐triggered control design for nonlinear systems with actuator failures and uncertain disturbances

Abstract

Summary Traditional adaptive event‐triggered design methods compensated for the event‐triggered error are not direct, and the stability analysis of resulting close‐loop systems is rather complicated. To alleviate the above restrictions, we propose a direct and simple event‐triggered co‐design method to solve the tracking control problem for parameter strict‐feedback systems with actuator faults and uncertain disturbances. By introducing a compensating terms in a smooth function form of a conventional control law and certain positive integrable functions, the effects of actuator faults and event‐triggered error can be compensated completely. Such a direct design method has the following features: (i) a direct compensation of the event‐triggered error is achieved without introducing any extra design parameters; (ii) it is not necessary to know any bound information on the parameters of event‐triggered threshold, and global asymptotic tracking control of the overall closed‐loop system is achieved; and (iii) the resulting stability criteria of the proposed event‐triggered control design are much simpler and easier to fulfill by virtue of the introduced co‐design method. Simulations are then carried out to validate the proposed schemes.

Event‐triggered adaptive finite‐time prescribed performance tracking control for uncertain nonlinear systems

“…32 The first method based on a static rule was named as the fixed threshold scheme 28 . [33][34][35] Considering input saturation and PPC, a finite-time controller was designed. 33 Aiming to nonlinear systems with pure feedback form, an adaptive output feedback ETC approach was given.…”

“…34 In view of unknown disturbances and actuator failures, an ETC design for nonlinear systems was presented. 35 The second method was the relative threshold scheme, whose threshold was adjusted in real time with the change of control law. It is easy to check that the method is more effective than the first scheme, especially when control signals are big.…”

“…Three event‐triggered threshold schemes were investigated for uncertain nonlinear systems 32 . The first method based on a static rule was named as the fixed threshold scheme 28 33‐35 . Considering input saturation and PPC, a finite‐time controller was designed 33 .…”

Command filter‐based event‐triggered adaptive neural network control for uncertain nonlinear time‐delay systems

“…Different from the traditional time‐triggered mechanism, where the output of traditional periodic sampling controller was employed in the system regardless of whether the system needs it or not, the idea of the event‐triggered control method is triggered only when the systems need, therefore, it can lead to great reduction of the communication burden and the resources wasting. Therefore, the study of event‐triggered control for nonlinear systems has also received much attention from researchers 30‐38 . In some details, A small‐gain approach was proposed to deal with the input‐to‐state stability (ISS) and robust event‐triggered control for nonlinear systems with respect to measurement errors in Reference 31.…”

“…In some details, A small‐gain approach was proposed to deal with the input‐to‐state stability (ISS) and robust event‐triggered control for nonlinear systems with respect to measurement errors in Reference 31. Some effective controller design methods for nonlinear systems by combining event‐triggered mechanisms with virtual control law were demonstrated in the literature 32‐38 …”