Active Control of an Isolation Table possessing Rotational Vibration due to Tower-like Elastic Payload

Abstract

This paper deals with the control system design for active isolation table that loads a dynamical object. When elastic loads are put on the isolation table, vibration modes of the table are changed. Therefore, the controllers for the active isolation table should be designed taking account of elastic loads.

In this research, an experimental active isolation table with an elastic load is built. Previous controller was designed to suppress horizontal vibration in addition to vertical vibration simultaneously. However, the performance of the previous controller was worse than the controller designed to suppress only horizontal vibration. The reason is estimated as the coupled vibration between the horizontal direction and the vertical direction is relatively low. In this research, focusing on the rotational motion appeared on the experimental apparatus, new controller to suppress rotational vibration is designed and its performance is examined. The presented controller showed good performance.