Design of sliding mode functional observers for time-delay systems of neutral type

This paper addresses the problem of estimating a linear function of the states of a class of linear time-delay systems of the neutral-type using sliding mode functional observer approach. Sliding mode functional observers proposed in this paper are of low-order and do not include the derivatives of the outputs. New conditions for the existence of sliding mode functional observers are derived. A design procedure for the determination of the observer parameters can also be easily derived based on the derived existence conditions.