Time-delayed state and unknown input observation

Abstract

The paper deals with the use of output anticipations to relax restrictions of the existing unknown input observer (UIO) design methods. The anticipation signals are treated as additional outputs of the original system, and a modified existence condition is presented. The modified condition is shown equal to the condition of system inversion. A computer simulation shows that the proposed UIO using the anticipation signals extends the applicability of UIO to a larger class of dynamic systems.