Loop shaping procedure for sampled-data control with optimal hold function

This paper is concerned with loop shaping procedure for sampled-data feedback control systems with optimal hold function. We first derive a solution of the general sampled-data H_∞ optimal control problem with optimal hold. We then show that the optimal hold function for the loop shaping procedure depends on the plant and the weighting functions, but it is independent of the given control performance level γ. We confirm the effectiveness of the proposed method by a numerical example.