Some results on an inverse problem in multivariable systems

A systems property of great interest to the control engineer concerns the system´s ability to exhibit those responses which are asked of it. This capability is governed by the nature of the system equations and the set of inputs which are available to ´force´ the system. Given the set of desired system responses Sy, and the system equations, this paper is concerned with characterizing the set of inputs which suffice to generate Sy.