versão impressa ISSN 0035-001X
Rev. mex. fis. vol.57 no.6 México dez. 2011
Comparative measurement of in plane strain by shearography and electronic speckle pattern interferometry
A. Martíneza, J.A. Rayasa, R. Corderob, and F. Labbec
b Universidad de Santiago de Chile, Ave. Bernardo O'higgins 3363, Santiago, Chile, email: firstname.lastname@example.org
c Universidad Técnica Federico Santa María, Ave. España 1680, Valparaíso, Chile email: email@example.com
Recibido el 15 de junio de 2011
Aceptado el 19 de octubre de 2011
In this work, an optical setup that gives the possibility of using either ESPI or ESPSI has been implemented to assess inplane strains induced on a composite sample. First, inplane ESPI was used to measure displacement fields, which later allowed us to evaluate the corresponding strain fields. Next, we applied ESPSI to measure the derivative of inplane surface displacements (the strains). The experimental results obtained by applying both techniques (ESPI and ESPSI) were compared. We found that the difference between the strain fields obtained by ESPSI and ESPI was roughly a constant. This result was expected since, although ESPI allows computing absolute strain values, the strains measured by ESPSI are relative to a reference that must be measured using an additional method. Once calibrated the system ESPSI, the ESPI could no longer be used. The strain field obtained in ESPSI is corrected by the sum of constant value calculated.
Keywords: Electronic speckle pattern interferometry; shearography; strain.
PACS: 06.20.f; 07.60.Ly; 06.60 Mr; 06.90.+v
Authors wish to thank economical support from Consejo Nacional de Ciencia y Tecnología (CONACYT_Mexico). The experimental results are part of the bilateral project between MexicoChile: Analysis of deformation mechanisms to fruit cuticle using laser interferometry techniques. CONACYTCONICYT project. The support of CONICYT (FONDECYT Preis 1090471, ANILLO Preis ACT98 and ANILLO Preis ACT95), UTFSM (DGIP Preis 250915) and USACH (DICYT, academic exchange program) is gratefully acknowledged.
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