Deformation Analysis of a Brake Caliper Using NDT-Technologies

This paper describes the proceeding for the analysis of surface deformations of a brake caliper in a test bench by ESPI and structured-light 3D-scanning. In the field of nondestructive testing the optical measurement technique provides possibilities for the detection of small surface deformations. As a whole-field, contactless and coherent-optical testing and measuring technique the Electronic Speckle Pattern Interferometry (ESPI) meets those requirements. Irregularities on body surfaces can be detected up to a range that lies in the range of the used laser wavelength. The recording of the surface geometry is followed by the analysis of the surface deformation, which also is carried out by ESPI. Deformations are then pictured on the undeformed geometry as a color pattern. Independently from the ESPI, this report also displays the use of light-structured 3D-scanning for the acquisition of the surface geometry. With an affiliated CAD environment the geometry data can be transferred into a digital model. This data then is available as 3D-geometry for further processing. Adjacent a FE-calculation (finite element calculation) can be carried out for a computer-simulated load on the specimen. Besides a quantitative, numeral acquisition of deformation, also in this case a color pattern is generated over the object surface, which equals the numeral analysis. Thereby a comparison between the FE-calculation and the experimental measurement results gained by ESPI is enabled. Besides an explanation of the optical fundamentals, the setups of both recording methods and the measurement proceeding are introduced in the following. The results of both methods are compared to each other, differences of the measurement results of deformation values are discussed.

1. Sirohi, R.S. and Fook Siong Chau. Optical Methods of Measurements, Wholefield Techniques, Marcel Dekker, Inc., 1999 ISBN: 0-8247-6003-4. 2. Lauer, S. and F. Fischer. Vermessung der Verformung eines Bremssattels mit dem Q300, Trier. 2011. 3. Hecht, E. Optik, Auflage: 4 Oldenburg Wissenschaftsverlag GmbH, München. 2005. 4. Dickl, S. Contouringverfahren mit getrennten Laserquellen, VDM Verlag Dr. Müller, Saarbrücken. 2008. 5. Schröder, G. Technische Optik, Vogelbuchverlag Würzburg 4. Auflage 1992. 6. Schmied, S. Diplomarbeit: Dehnungsverteilung in Beton bei Dübeln unter Querlast, Trier. 7. Käferstein, B. 3D-Verformungsmessungen auf 10nm genau, IMW-Institutsmitteilung Nr. 23, http://www.imw.tuclausthal. de/fileadmin/Bilder/Forschung/Publikationen/Mitt_1998/98_20.pdf. 8. Schuth, M. Shearografie zur Dehnungsanalyse, VDI-Berichte, Reihe 8 Nr. 539, VDI-Verlag, Düsseldorf. 1986. 9. Koehldorfer, W. Finite-Elemente-Methoden mit CATIA V5, 1. Auflage Hanser Verlag. 10. Dantec Dynamics GmbH, Introduction of Speckle-Pattern-Interferometrie, Report No 200401. 11. Schnell,W.A., D. Gross and W. Hauger. Technische Mechanik 2, 7. Auflage Springer Verlag.
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