Value set boundary computation of uncertainty structures

A robust analysis approach based on the computation of value set boundaries is presented. In the first part, the calculation of the boundary of regions corresponding to uncertain poles, zeros and delay plants is extended to more general parametric factorizable uncertain systems. In the second part, based on the Tree Structured Decomposition (TSD) concept, the operation (+,-,?,?) among boundaries of simple value sets is studied. Using this approach, we present a procedure which computes the boundary of even more general value sets, in polynomial time and without incrementing the total amount of input data. Although a ?-search needs to be made in all these cases, the computation time at each frequency is performed in polynomial time.