A Note on Sampled-Data Observers

TL;DR

This paper introduces a new method for designing sampled-data observers that maintain the stability and convergence properties of continuous-time observers, using a novel output predictor applicable to various systems.

Contribution

It proposes a unified design approach for sampled-data observers with stability and convergence guarantees, based on a new output predictor combining inter-sample and ZOH-predictors.

Findings

Observers inherit continuous-time performance characteristics

The approach applies to a wide class of systems

Ensures exponential convergence in noiseless conditions

Abstract

We present a new approach for deriving sampled-data observers from continuous-time observers that feature an Input-to-Output Stability property with respect to the output measurement noise and exponential convergence in the noiseless case. The design approach applies to a wide class of systems and yields sampled-data observers that inherit all performance characteristics of the underlying continuous-time observers. The main component of the proposed sampled-data observer is a novel output predictor that encompasses both inter-sample predictors and ZOH-predictors.