Stable Inversion of MIMO Linear Discrete Time Non-Minimum Phase Systems∗

A novel technique to achieve output tracking via stable inversion of non-minimum phase linear systems is presented wherein the desired signal is obtained from field measurements, and hence corrupted by noise. The earlier approach to stable inversion does not take into account the noise in the system. The unknown input decoupled observer approach is applicable only to minimum phase systems. Moreover, the unobservable states are inadequately constructed resulting in inferior output tracking in the presence of noise. In this paper we extend this procedure to non-minimum phase systems. We present the novel Stable Dynamic model Inversion (SDI) approach which is applicable to non-minimum phase systems, and takes into account the presence of noise in target time histories.