Funnel control for nonlinear systems with arbitrary relative degree using high-gain observers. (July 2019)

• Record Type: Journal Article
• Authors: Chowdhury, Dhrubajit; Khalil, Hassan K.
• Is Part Of: Automatica. Volume 105(2019)
• Page Start: 107
• Page End: 116
• Publication Date: 2019-07
• Subjects: Performance funnel -- High-gain observers -- Nonlinear systems; Automatic control -- Periodicals; Automation -- Periodicals; 629.805
• DOI: 10.1016/j.automatica.2019.03.012
• Languages: English
• ISSNs: 0005-1098

Abstract

Abstract: We propose a new algorithm for controlling the transient behavior of the tracking error for nonlinear systems with arbitrary relative degree. In tracking problems, the transient behavior of the error is more important than the behavior of its derivatives. We introduce a concept of virtual output, which converts an arbitrary relative degree system into a relative degree one system. The virtual output is chosen in such a way that the difference between the virtual output and the tracking error can be made arbitrarily small all the time. Assuming that the state derivatives are not available for feedback we use a high-gain observer to estimate the derivatives and construct the virtual output.