Analysis and design of uniaxial passive vibration isolators considering stiffness and bandwidth limitations.

Abstract

There are two main aims in this dissertation. The first one is to categorize various vibration isolator designs and then formulate their isolation properties in a general framework. The second objective is to come up with better isolator designs based on the conducted analyses. In order to make the analyses easier, electrical filtering terminology is extensively utilized throughout the thesis. All the analyses are conducted with non-dimensional numbers, which enables fair comparisons among various isolation systems. As a result, concise formulas are obtained for quantifying the performances of different types of vibration isolators. Consequently, supplementary numerical examples are provided. Fundamentally, it is hard to obtain stiff low-pass filter type vibration isolators or wide-band band-stop filter type vibration isolators by just passive means. It has been shown that anti-resonance phenomenon is the key to attain high stiffness and/or large bandwidth in passive vibration isolation systems. Based upon the anti-resonance phenomenon, three new isolator designs are developed. Finally, comparative numerical studies are conducted with the existing systems.