L1 Adaptive Output Feedback for Nonsquare Systems With Arbitrary Relative Degree

• 成果类型: Article
• 署名作者: Lee, Hanmin; Cichella, Venanzio; Hovakimyan, Naira
• 署名单位: University of Iowa; University of Illinois System; University of Illinois Urbana-Champaign
• 刊物名称: IEEE TRANSACTIONS ON AUTOMATIC CONTROL
• ISSN/ISSBN: 0018-9286
• DOI: 10.1109/TAC.2020.2989279
• 发表日期: 2021
• 页码: 895-901
• 关键词: adaptive control; Adaptive systems; Nonlinear systems; nonsquare systems

摘要

This article considers adaptive output-feedback control problem for nonsquare multi-input-multi-output systems (MIMO) with arbitrary relative degree. The proposed controller, based on the L-1 adaptive control architecture, is designed using the right interactor matrix and a suitably defined projection matrix. A state-output predictor, a low-pass filter, and adaptive laws are introduced that achieve output tracking of a desired reference signal. It is shown that the proposed control strategy guarantees closed-loop stability with arbitrarily small steady-state errors. The transient performance in the presence of nonzero initialization errors is quantified in terms of decreasing functions. Rigorous mathematical analysis and illustrative examples are provided to validate the theoretical claims.