H∞ sampled-data control considering computational delays

This paper considers a sampled-data H-infinity control problem which takes into account the computational time delay. The conditions for the existence of a solution are derived in the transfer function domain using chain scattering-matrix descriptions where a fictitious input is induced to represent the uncertainty due to sampling and inherent time delay. A set of controllers consisting of a predictor to compensate for the time delay is then constructed by solving two certain coprime factorizations. Finally, a real-time control design example is given to illustrate the superiority of the present method over others as the sampling period increases. (C) 1998 John Wiley & Sons, Ltd.