Suboptimal dead beat control systems for a non-minimum phase plant with input and measurement noise

Recently, a design of model matching and adaptive control systems under the presence of measurement noise is reported by employing a nonminimal order state observer. But this method can be used only for the case where the plant is stably invertible. In this paper, it will be shown that the idea is also applicable to the case of dead beat control for a plant having unstable zeros. The proposed method can be implemented by simple calculation comparing with the design of Kalman filter or H_∞ control. So the proposed method is adequate for an adaptive control in which the controllers must be calculated on line.