Edge results for robust stabilization of interval plants with generalized compensators

It has recently been shown that stabilizing an interval plant family with a first-order compensator is equivalent to only sixteen of the extreme plants. In the present work, an attempt is made to extend this result to that with generalized compensators. It is shown that a generalized compensator robustly stabilizes an interval plant family if and only if it stabilizes thirty-two one-dimensional edges connecting extreme points of the given interval plant. When the variation of the coefficients is limited to denominator (or numerator), the number of edges to the checked will reduce to eight