American Journal of Mechanical Engineering
ISSN (Print): 2328-4102 ISSN (Online): 2328-4110 Website: Editor-in-chief: Kambiz Ebrahimi, Dr. SRINIVASA VENKATESHAPPA CHIKKOL
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American Journal of Mechanical Engineering. 2015, 3(6), 252-256
DOI: 10.12691/ajme-3-6-20
Open AccessArticle

Reciprocity in Experimental Modal Analysis

Peter Pavelka1, , Róbert Huňady1, Martin Hagara1 and František Trebuňa1

1Department of Applied Mechanics and Mechanical Engineering, Faculty of Mechanical Engineering, Letná 9, 042 00 Košice, Slovakia

Pub. Date: December 17, 2015

Cite this paper:
Peter Pavelka, Róbert Huňady, Martin Hagara and František Trebuňa. Reciprocity in Experimental Modal Analysis. American Journal of Mechanical Engineering. 2015; 3(6):252-256. doi: 10.12691/ajme-3-6-20


This paper deals with modal analysis and estimation of modal parameters of an analyzed structure. An aim of the paper is to verify one of four basic assumptions considered in modal testing. This property is reciprocity. Reciprocity means that the frequency response function measured between two degrees-of-freedom must be the same regardless of which degree-of-freedom is input or output. In the paper the experimental and numerical modal analysis of a cantilever beam are presented. There are described two experimental measurements focused on reciprocity of measurement process. Measured mode shapes are compared to each other using Cross Modal Assurance Criterion. The results of experimental and numerical modal analysis are compared to each other.

experimental modal analyses reciprocity cantilever beam cross MAC CMIF

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