On the Synthesis of Unknown-Input Observers and Inverse Systems by Recursive Algorithms

Abstract

In the present work the synthesis of unknown-input observers and inverse systems is approached in the state space by using some iterative computational procedures which have been previously developed by the authors in order to detect the most important structural properties of linear time-invariant dynamical systems. A substantial feature of this approach is the possibility of taking into account the constraint of being stable for the synthesized observer or inverse system. Moreover new very simple necessary and sufficient conditions for unknown-input state observability and invertibility, both without and with stability constraints, are obtained.