Approximation-based adaptive tracking of a class of uncertain nonlinear time-delay systems in nonstrict-feedback form

作者：Yoo Sung Jin^*

来源：International Journal of Systems Science, 2017, 48(7): 1347-1355.

DOI：10.1080/00207721.2016.1256450

• Nonstrict-feedback
• predefined performance
• adaptive control
• nonlinear systems
• unknown time-varying delays

This paper investigates a predefined performance control problem for adaptive tracking of uncertain nonlinear time-delay systems in nonstrict-feedback form. Nonstrict-feedback nonlinearities, time-varying delays and external disturbances are assumed to be unknown. Based on the exponential decaying design functions denoting the preassigned bounds of transient and steady-state tracking errors, some variable separation lemmas are derived to design an approximation-based robust adaptive control scheme in the presence of nonstrict-feedback time-delayed nonlinearities. The proposed control system guarantees that a tracking error remains within a predesigned bound for all t >= 0 and converges to a preselected neighbourhood of the origin. Compared with the existing results in the literature, the main contribution of this paper is to provide a solution on the guaranteed performance control in the presence of unknown nonstrict-feedback nonlinearities related to all delayed state variables. Simulation results illustrate the effectiveness of the proposed methodology.

• 出版日期2017