Global adaptive regulation of feedforward nonlinear time‐delay systems by output feedback. (7th November 2016)

• Record Type: Journal Article
• Authors: Jia, Xianglei; Xu, Shengyuan; Cui, Guozeng; Zhang, Baoyong; Ma, Qian
• Is Part Of: International journal of robust and nonlinear control. Volume 27:Number 14(2017)
• Page Start: 2451
• Page End: 2472
• Publication Date: 2016-11-07
• Subjects: global state regulation -- dynamic gain observer -- output feedback -- feedforward -- backstepping; Automatic control -- Periodicals; Control theory -- Periodicals; Nonlinear systems -- Periodicals; 629.836
• DOI: 10.1002/rnc.3691
• Languages: English
• ISSNs: 1049-8923

Abstract

Summary: The problem of global adaptive state regulation is investigated via output feedback for uncertain feedforward nonlinear time‐delay systems. Compared with existing results, our control schemes can be applicable to more general nonlinear time‐delay systems because of combining the low‐gain scaling approach with the backstepping method. In particular, we allow that there exist uncertain output function and uncertain growth rate imposed on nonlinear terms. Also, one considers a class of nonlinear systems with main‐axis delay. By the Lyapunov–Krasovskii theorem, delay‐independent controllers are proposed by constructing novel low‐gain observers driven by system input, to regulate the states of original system while all the closed‐loop signals are globally bounded. Furthermore, two examples are given to illustrate the usefulness of our results. Copyright © 2016 John Wiley & Sons, Ltd.