Design of a test setup for the characterization of vibration isolators

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2013
Uz, Canan
Design of a test setup to investigate dynamic characteristics of a vibration isolator has been extensively studied over the years and international standards are regulated to explain the basis of the measurements. In this thesis, design efforts to develop a custom test setup for measuring dynamic stiffness of vibration isolators are presented. The setup is designed to conduct dynamic stiffness measurements for various static preload values and over a certain (target) frequency range. Direct Method has been selected among the methods defined by standards found in the literature. In order to investigate the effect of basic design parameters of the test setup on its overall performance, an equivalent eight degree of freedom lumped parameter model of the test setup is used which takes into account the basic dimensions and materials used for main structural components of the proposed setup design as well as the inertial characteristics of the isolators. Using the equivalent model, virtual tests are performed and the accuracy of the test setup is studied for various testing scenarios. A major work that is conducted as part of this work is to come up with a procedure that will enable tuning of the setup parameters such that the percent error on measured dynamic stiffness of various types of isolators are minimized for the case when various levels of error are present in measured displacement and force amplitudes. Moreover, normal modes of the main structure of the setup are analyzed in Finite Element Analysis software for different configurations. Dimensions, equivalent stiffness and mass calculations of the components in the discrete model are updated according to the Finite Element Analysis results. At the end of this work, detail design and 3-D solid assembly of the setup is modeled. Sample experiments are performed to validate the test setup (virtual tests).

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Citation Formats
C. Uz, “Design of a test setup for the characterization of vibration isolators,” M.S. - Master of Science, Middle East Technical University, 2013.