The Unknown Input Observer and its Advantages with Examples

2015/04/27 by Sam Nazari, Nazari, Sam
Engineering · #Adaptive Control of Nonlinear Systems #Advanced Control Systems Optimization #FOS: Electrical engineering #Stability and Control of Uncertain Systems #Systems and Control (eess.SY) #electronic engineering #information engineering

paper · pdf · doi:10.48550/arxiv.1504.07300

openalex publication_date 2015/04/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

This brief memo reviews the theory of Unknown Input Observers (UIO) for state estimation in systems subject to disturbance inputs that are not known a priori. One main advantage of the UIO is that the observer structure naturally decouples the plant inputs from the state estimation process. This advantage is highlighted in three example dynamic systems commonly found in control theory. It is shown that the estimation error for all three systems asymptotically approaches zero by application of the UIO under the influence of dynamic disturbances.

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