Robust output tracking with structured perturbations: A multiple model control based approach

The robust tracking problem for a family of linear uncertain plants is cons idered. The solution presented is in terms of a deterministic, time-varying compensator and of a supervisor. The compensator may assume a finite numbe r of possible different configurations, at least one of the which stabilife s the plant. The task of the supervisor is that of determining the switchin g instants of a scanning among the elements of the family, according to a s uitably, defined experimental test on the tracking error. The appealing,fea tures of the paper are that a parametric stability, margin is defined with no particular assumption on the uncertainty structure of the plant and that a precise and simple algorithm for defining the finite,family, of the diff erent possible configurations of the time-varying controller is given.