Symmetric Controller Design for Symmetric Plant Using Matrix Inequality Conditions

For symmetric systems, the useage of symmetric controllers is known to be effective. The existence conditions of the controller have been shown in several studies. They require the symmetry of the plant as well as the control specifications. This paper describes the condition by matrix inequalities and relaxes it to be applicable to the case of non-symmetric sepcifications for the symmetric H∞controller design. Additionally, the optimal symmetric controller design for mechanical systems is investigated as a special case.