Bilinear Optimal Control Theory and its Application to Semi-Active Vibration Isolation Control

Abstract

In vibration isolation control problem, semi-active control methods in which coefficient of viscous damping or spring constant are varied effectively have been proposed and expected to realize a high performance with a little energy consumption. However, the semi-active system is classified into a bilinear system which belongs to a nonlinear system and its controller design is not easy. In this study, a bilinear optimal control theory is established by adopting the damping force in criteria function and it is applied to a semi-active base isolation problem. This study deals with 10 stories structure model corresponding to an actual building and the dynamics of an oil damper is taken into consideration by using the Maxwell model in the modelling. Moreover, the dynamics of disturbance is taken into account, and the controller is designed for the augmented bilinear system which includes both the control object and the disturbance. And the computer simulation is carried out by taking account of the delay to switch the coefficient of dampers in order to compare the performance on semi-active base isolation controls designed by the proposed method with skyhook control method and passive isolations. As a result, the usefulness of the present method was demonstrated.