Model Following Adaptive Control of Multirate Sampling Systems

Abstract

This paper deals with model following adaptive control of linear time-invariant systems with two sampling rates : a slower one for the output and a faster one for the input. It is known that intersample ripples often arise in the outputs of the closed-loop multirate sampling systems although multirate control has interesting advantages. In this paper, a ripple-suppressed multirate model following control scheme is presented. A state observer is designed at the output sampling instants and a filter is constructed at the input sampling instants in order to estimate the output at the intersample instants of the outputs. Next, an adaptive version of the algorithm for systems with unknown parameters is shown. Experimental results applied to a position servo system with a supersonic sensor are given to indicate the effectiveness.