An Application for Tank System and its Analysis in Frequency Domain of Two-Degree-of-Freedom Optimal Type-1 Servo System

Study on a Trade-off between Influence of Observation Noise and Disturbance Rejection and Robust Stability

Abstract

In this paper, we do an experimental study of two-degree-of-freedom optimal type-1 servo system based on the LQ (linear quadratic) method using a tank system. First, the experiments for the state feedback system which takes into account of a trade-off between low frequency sensitivity and guaranteed stability margin by using an integral gain are carried out. Next, we extend to the output feedback case and carry out the experiments to show the effectiveness of the LTR (loop transfer recovery) method or the integral gain. As the results of these experiments and its analysis in frequency domain, the influence of an observation noise which appears in the control input, the effect of disturbance rejection and robust stability for a plant perturbation are clarified.