Observer design procedure for time delay systems

This paper presents a simple observer design procedure for a class of linear/nonlinear differential state delayed control systems. This procedure is based on the unknown input observer theory and the utilization of stability criteria for time-delay systems. The term associates with the delayed state are decomposed into two portions: a matched portion and a mismatched portion. Provided that the mismatched portion satisfies a certain matrix rank condition, then a full state vector observer, with any prescribed stability margin, can be constructed using a simple and systematic procedure. A numerical example is given to illustrate the design procedure and its advantages over existing design methods.