Adaptive controller design with prescribed performance for switched nonstrict feedback nonlinear systems with actuator failures

Abstract

This article is concerned with the adaptive output-feedback control of switched nonstrict feedback nonlinear systems. By introducing a novel error surface, an adaptive control strategy is proposed for the general case where the nonlinear functions and the control gain functions are unknown, and the states are unmeasurable. The considered switched nonlinear system contains unknown actuator failures, which are modeled as both loss of effectiveness and lock-in-place. In order to improve the transient performance in the presence of unknown actuator failures, the prescribed performance approach is used. The "explosion of complexity" problem is avoided through using low-pass filters. The stability of the closed-loop system under arbitrary switching is shown using Lyapunov stability theory, based on which, the tracking error is shown to converge to a small residual set with the prescribed performance bounds. The advantages of the proposed technique are verified through simulations of two numerical and practical examples.

Adaptive NN control for nominal backstepping form with periodically time‐varying and nonlinearly parameterized switching functions

“…However, most of these control strategies are proposed based on the Backstepping technique, which ignores the EOC issue. To deal with this problem, some control schemes are proposed [41–43] by combining command filter or DSC technique with the PPC method. For example, Cui et al.…”

“…To obtain better performance, prescribed performance control (PPC) is proposed in [32,33], where the transient and steady-state performance of the tracking error are assured simultaneously. And thus, in recent years, a large number of meaningful results are reported [34][35][36][37][38][39][40][41][42][43], by using the PPC technique. For instance, by introducing a novel error transformation function, an event-triggered PPC scheme is developed for the nonlinear system with unknown control direction and actuator fault [34].…”

Adaptive NN Control for Nominal Backstepping Form with Periodically Time-varying and Nonlinearly Parameterized Switching Functions

“…To obtain better performance, predefined performance control (PPC) is proposed in [32], [33], where the tracking error converges to a predetermined small set of residuals, the speed of convergence is great than or equal a pre-specified value and the maximum permissible overshoot is below a sufficiently small pre-specified constant. Obviously, this method takes into account the transient and steady-state performance of the system simultaneously, and thus, in recent years, a large number of meaningful results are reported [34]- [38] by using the PPC technique. For instance, by introducing a novel error transformation function, an event-triggered PPC scheme is developed for the nonlinear system with unknown control direction and actuator fault [34].…”

“…Moreover, the tracking control with prescribed performance is addressed for the uncertain strict-feedback nonlinear systems in [35], [36]. Furthermore, some control strategies by combining with the PPC method are proposed for the switching systems in [37], [38], such that tracking performance is ensured. However, it is worth noting that few scholars pay attention to the prescribed tracking control performance for the nonlinear systems with unknown PTVPs and switching functions.…”

“…Compared with the tracking control performance obtained in [28]- [31] where the tracking error converges to a small but unknown residual set, in this context, the tracking error is always restricted to the given region defined by the performance functions and converges with the performance function. Although the PPC problem is solved [10], [34]- [38], they do not consider nonlinear systems with unknown PTVNP switching functions.…”