Functional Observability and the Design of Minimum Order Linear Functional Observers

Abstract

The design of a minimum-order linear functional observer for linear time-invariant systems has been an open problem for over four decades. This technical note provides a solution to this problem. The technical note also introduces the concept of <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Functional Observability/Detectability</i> and shows that the well-known concept of Observability/Detectability is a special case of <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Functional Observability/Detectability</i> .