Modelling and control techniques of an active vibration isolation system

In the field of high-resolution measurement and manufacturing, effective anti-vibration measures are required to obtain precise and repeatable results. This is particularly true for experiments or processes where the typical amplitudes of the ambient vibration and the dimensions of the investigated or manufactured structures fall in the same range, e.g. submicron semiconductor production, holographic interferometry, confocal optical imaging, and scanning probe microscopy. In the active vibration isolation system examined, signals are acquired by extremely sensitive vibration detectors, and the vibration is reduced using either local analog feedback control or digital model-based control to drive electrodynamic actuators. This papers deals with the modelling and control techniques of such an active vibration isolation system. The modelling, parameter identification, and model updating procedure are described. The experimental setup for testing such an antivibration system is described, and the measured transmissibility curves for the passive and active system being driven by local analog feedback controllers are provided. Finally, the simulated transmissibility curves of the passive system and the active system using a decentralized digital loop shaping controller and a centralized model based controller are given and the results are discussed.

Modelling and control techniques of an active vibration isolation system Conference Paper