Robust Mixed-Mu Synthesis Performance for Mass-Spring System with Stiffness Uncertainty

The purpose of this research is to study the robust feedback control of a mass-spring system with two masses and two springs. The main performance objective is to keep constant the displacement of the mass affected by a disturbance. Compensators designed by the mu-synthesis method allow us to study how the performance changes with the stiffness constant uncertainly, when the bandwidth of disturbance is either below or above the resonance frequencies. In one case we only measure the displacement of the mass that we want to minimize; in the another case the measurements of the displacement for both masses are measured