3-D Analytical Treatment of Base Isolation for Mechanical Testing Systems

Year 2018, Volume: 5 Issue: 1, 1 - 15, 26.03.2018

Mehmet Şahin

Abstract

A mathematical model for dynamic
analysis of vibration isolation systems is presented. The model is based on
small deformation mechanics of 3-D rigid body with 6-DOF and supported by
flexible structural members. The mass, static stiffness and damping matrices
for the system are derived. Eigen-analysis using the presented model and
solution method are applied to a real spacecraft vibration test system with
base isolation. A finite element model of the system is also developed. The
results of the proposed math model, FE model and test results of a real
vibration testing system are compared. The math model solution results agree
well with the FEM model and actual test results. The model can be used in the
design of the engineering structures with base isolation such as vibration and
acoustic test systems, large static and dynamic testing systems, buildings etc.

Keywords

Vibration isolation, rigid-body motion, eigen-analysis

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