Global Output-Feedback Tracking for Nonlinear Cascade Systems with Unknown Growth Rate and Control Coefficients  

作　　者：YAN Xuehua LIU Yungang WANG Qingguo 

机构地区：[1]School of Electrical Engineering,University of Jinan [2]School of Control Science and Engineering,Shandong University [3]Department of Electrical and Computer Engineering,National University of Singapore

出　　处：《Journal of Systems Science & Complexity》2015年第1期30-46,共17页系统科学与复杂性学报（英文版）

基　　金：supported by the National Natural Science Foundation of China under Grant Nos.61325016,61273084,61233014,and 61304013;the Natural Science Foundation for Distinguished Young Scholar of Shandong Province of China under Grant No.JQ200919;the Independent Innovation Foundation of Shandong University under Grant No.2012JC014;the Doctoral Foundation of Jinan University under Grant No.XBS1413

摘　　要：This paper deals with the global practical tracking problem by output-feedback for a class of uncertain cascade systems with zero-dynamics and unmeasured states dependent growth.The systems investigated are substantially different from the closely related works,and have zero-dynamics,unknown growth rate,and unknown time-varying control coefficients.This makes the problem much more difficult to solve.Motivated by the authors' recent works,this paper proposes a new adaptive control scheme to achieve the global practical tracking.It is shown that the designed controller guarantees that the state of the resulting closed-loop system is globally bounded and the tracking error converges to a prescribed arbitrarily small neighborhood of the origin after a finite time.This is achieved by combining the methods of universal control and dead zone with backstepping technique,and using the framework of performance analysis in the closely related works.A numerical example demonstrates the effectiveness of the theoretical results.

关 键 词：Adaptive control dynamic high-gain global practical tracking OUTPUT-FEEDBACK uncertain nonlinear systems. 

分 类 号：O231[理学—运筹学与控制论]