Robust Servo Control Design Using the <I>H_&infin;&mu;</I> Method

Abstract

This paper presents a case study of a servo control synthesis to design either a one degree-of-freedom (ODF) controller or a two-degree-of-freedom (TDF) one. In order to achieve nominal performance and meet robust stability specifications, the Hinfin;mu; synthesis is applied for controller design to take the structured uncertainty of the plant into consideration. In this way, the controller can be designed to provide the track of the predefined reference signal, reduces the effects of the disturbances and the uncertainties on performances. In the paper, the design strategy is illustrated for an inverted pendulum device. It is demonstrated that ODF controllers do not satisfy requirements of practical application and therefore TDF controllers are required.