Share Email Print

Proceedings Paper

Holographic Interferometry based on photorefractive crystal to measure 3D thermo-elastic distortion of composite structures and comparison with finite element models
Author(s): C. Thizy; F. Eliot; D. Ballhause; K. R. Olympio; R. Kluge; A. Shannon; G. Laduree; D. Logut; M. P. Georges
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Thermo-elastic distortions of composite structures have been measured by a holographic camera using a BSO photorefractive crystal as the recording medium. The first test campaign (Phase 1) was performed on CFRP struts with titanium end-fittings glued to the tips of the strut. The samples were placed in a vacuum chamber. The holographic camera was located outside the chamber and configured with two illuminations to measure the relative out-of-plane and in-plane (in one direction) displacements. The second test campaign (Phase 2) was performed on a structure composed of a large Silicon Carbide base plate supported by 3 GFRP struts with glued Titanium end-fittings. Thermo-elastic distortions have been measured with the same holographic camera used in phase 1, but four illuminations, instead of two, have been used to provide the three components of displacement. This technique was specially developed and validated during the phase 2 in CSL laboratory. The system has been designed to measure an object size of typically 250x250 mm2; the measurement range is such that the sum of the largest relative displacements in the three measurement directions is maximum 20 μm. The validation of the four-illuminations technique led to measurement uncertainties of 120 nm for the relative in-plane and out-of-plane displacements, 230 nm for the absolute in-plane displacement and 400 nm for the absolute out-of-plane displacement. For both campaigns, the test results have been compared to the predictions obtained by finite element analyses and the correlation of these results was good.

Paper Details

Date Published: 13 May 2013
PDF: 12 pages
Proc. SPIE 8788, Optical Measurement Systems for Industrial Inspection VIII, 878807 (13 May 2013); doi: 10.1117/12.2020542
Show Author Affiliations
C. Thizy, Univ. de Liège (Belgium)
F. Eliot, EADS-Astrium (France)
D. Ballhause, EADS-Astrium (Germany)
K. R. Olympio, EADS-Astrium (Germany)
R. Kluge, EADS-Astrium (Germany)
A. Shannon, European Space Agency ESTEC (Netherlands)
G. Laduree, European Space Agency ESTEC (Netherlands)
D. Logut, EADS-Astrium (France)
M. P. Georges, Univ. de Liège (Belgium)

Published in SPIE Proceedings Vol. 8788:
Optical Measurement Systems for Industrial Inspection VIII
Peter H. Lehmann; Wolfgang Osten; Armando Albertazzi, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?