Bounds on a gramian-based Interaction Measure for robust control structure selection

This paper reviews a method for approximating the bounds on a gramian-based Interaction Measure (IM) for systems described by uncertain parametric models. The considered IM is the Participation Matrix. The reviewed method is based on analyzing the uncertainty in the area enclosed by the Nyquist curve. Conditions for the exactitude of this method are derived, and implementation issues are discussed.