High‐gain observers in nonlinear feedback control

TLDR

High‑gain observers have a long history in nonlinear control, originating from early work on state estimation. This paper aims to present the main ideas and results on high‑gain observers and their applications in control. The authors illustrate key features with a motivating second‑order example and then develop a unified theory that accommodates modeling uncertainty and measurement noise. They show that high‑gain observers can be effectively used for robust control of minimum‑phase nonlinear systems. © 2013 John Wiley & Sons, Ltd.

Abstract

SUMMARY In this document, we present the main ideas and results concerning high‐gain observers and some of their applications in control. The introduction gives a brief history of the topic. Then, a motivating second‐order example is used to illustrate the key features of high‐gain observers and their use in feedback control. This is followed by a general presentation of high‐gain‐observer theory in a unified framework that accounts for modeling uncertainty, as well as measurement noise. The paper concludes by discussing the use of high‐gain observers in the robust control of minimum‐phase nonlinear systems. Copyright © 2013 John Wiley & Sons, Ltd.