Output feedback stabilization of sampled-data systems by first-order hold input

This paper discusses sampled-data control design by the first-order hold input. When we use digital devices to control systems, we need a sampled-data control input. Here, we employ the first-order hold sampled-data control input. Since the first-order hold input can be regarded as a delayed signal, the closed-loop system with the first-order hold state feedback control becomes a system with time-varying delay in state. We first give a sufficient condition for the stability of the closed-loop system in terms of linear matrix inequalities(LMIs). Based on such a stability condition, we propose a design method of the first-order hold sampled-data state feedback controller.