A design of switched controllers for force control system

In real control systems, there are limitations on variables of inputs, states and outputs. If these values become beyond the limited ones, systems may become unstable, or as the worst scenario, may result in unrecoverable destructions. One of the promising ways to overcome this problem is to develop a switching-based controller. In the switching-based control system, multiple pre-designed controllers are switched online by a supervisor according to a situation of the state of the plant. However, any useful design approach for such controllers has not been developed yet. In this paper, the concept of switching-based controller and H/sub /spl infin// controller design are merged into one design algorithm. Each controller is designed via sensitivity minimization measured by H/sub /spl infin// norm. The weighting function is appropriately selected for each controller so as to arrange the switched controllers suitably. The proposed method is applied to a force control system and a method of design of each controller is discussed. Finally, numerical results are shown to verify the usefulness of the proposed method.