EFFECT OF MISSING PATH AND FORCE ON VIBRATION RESPONSE PREDICTION

Abstract

Accurate prediction of the vibration responses is an essential requirement during the design and optimization stages of mechanical structures. For this reason, a vibration response prediction (VRP) methodology, based on a set of frequency response functions (FRF) and operational responses, is established. In this methodology, defining the sources and transmission paths of the structure accurately is critical. Since it is based on the FRFs of the system, unconsidered sources and/or missing path result in inaccurate predictions. The goal of this paper is to present the effect of a missing path on the prediction results. In accordance with this purpose, a three degree-of-freedom system will be investigated analytically and VRP methodology will be applied along with the calculated receptances and displacements of the system.

Keywords

• vibration response,matrix inversion,cross-coupling,3 DOF systems

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