Observer Synthesis for Uncertain Nonlinear Systems With Nonuniformly Sampled and Delayed Output

Abstract

This article presents a novel observer synthesis for nonuniform observable uncertain nonlinear systems with sampled (constant and non-uniform intervals) and disturbed delayed output. An observer with a cascade structure is proposed in order to obtain (in a continuous way) the estimated free-delay state vector. The base of the cascade structure is a continuous-discrete observer that achieve the continuous estimation of the delayed state, which reduces the convergence time and allows to reduce the remaining subsystems in the cascade. The rest of the cascade structure is composed by predictors that compensate the delay induced by the original signal. The performance of the observer is evaluated by estimating the state of an uncertain chaotic system with delayed measurements by considering different scenarios.