International Journal of Precision Engineering and Manufacturing

Korean Society for Precision Engineering (한국정밀공학회)
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Application of ESPI to Measurement of Out-of-plane Displacement in a Spot Welded Canti-levered Plate

  • Baek, Tae-Hyun (School of Mechanical Engineering, Kunsan National University) ;
  • Kim, Myung-Soo (School of Electronics and Information, Kunsan National University) ;
  • Na, Eui-Gyun (School of Mechanical Engineering, Kunsan National University) ;
  • Koh, Seung-Kee (School of Mechanical Engineering, Kunsan National University)
  • Published : 2003.09.01
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Abstract

Electronic Speckle Pattern Interferometry (ESPI) has been recently developed and widely used because it has the advantage of being able to measure surface deformations of engineering components and materials in industrial areas without contact. The speckle patterns formed with interference and scattering phenomena can measure not only the out-of-plane but also the in-plane deformations. Digital image equipment processes the information included in the speckle patterns and displays the consequent interferogram on a computer monitor. In this study, the experimental results of a canti-levered plate using ESPI were compared with those obtained from the simple beam theory. The ESPI results of the canti-levered plate, analyzed by 4-step phase shifting method, are close to the theoretical expectation. Similarly, out-of-plane displacements of a spot welded canti-levered plate were also measured by ESPI with 4-step phase shifting technique. The phase map of the spot welded canti-levered plate is quite different from that of the canti-levered plate without spot welding.

Keywords

References

  1. Cloud, G. L., Optical Methods of Engineering Analysis, New York, Cambridge University Press, pp. 343-407, 1995
  2. Petzing, J. N. and Tyrer, J. R., 'Recent Developments and Applications in Electronic Speckle Pattern Interferometry,' Journal of Strain Analysis, Vol. 33, No. 2, pp. 153-169, 1998 https://doi.org/10.1243/0309324981512887
  3. Rastogi, P. K. (Editor), Digital Speckle Pattern Interferometry and Related Techniques, John Wiley and Sons, Ltd., 2001
  4. Kim, K. S., Kim, I. K., Kang, Y. J., Roh, K. W., Ryu, W. J. and Cheong, S. K-., 'The Electronic Laser Interferometry and Laser Heating Method for Residual Stress Determination,' KSME International Journal, Vol. 14, No. 7, pp. 715-721, 2000 https://doi.org/10.1007/BF03184456
  5. Kim, K. S., Jang, W. S., Hong, M. S., Kang, K. S., Jung, H. C., Kang, Y. J. and Yang, S. P.. 'Thermal Strain Analysis of Composite Materials, by Electronic Speckle Pattern Interferometry,' KSME International Journal, Vol. 14, No. 5, pp 477-482, 2000 https://doi.org/10.1007/BF03185649
  6. Baek, T. H., Kim, M. S., Na, E. G. and Koh, S K., 'Measurement of Out-of-plane Displacement ir a Spot Welded Canti-levered Plate using Laser Speckle Interferometry with 4-step Phase Shifting Technique,' Korean Society of Precision Engineering (in Korean), Vol. 19, No. 3, pp. 66-72, 2002
  7. Ghiglia, D. C. and Pritt, M. D., Two-Dimensional Phase Unwrapping, John Wiley & Sons, Inc., New York, 1998
  8. Adobe Photoshop, Version 5.5
  9. Baek, T. H., Kim, M. S. and Kim, S. I., 'Measurement of Out-of-plane Displacement in a Canti-levered Plate using Laser Speckle Interferometry with 4-step Phase Shifting and FFT Filtering Technique,' Proceedings of the KSNT 2000 Spring Conference, The Korean Society for Nondestructive Testing (in Korean), pp. 535-546, 2000