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Development of the Natural Frequency Analysis System to Examine the Defects of Metal Parts

금속 부품의 결함 판단을 위한 고유 주파수 분석 시스템 개발

  • Received : 2015.03.22
  • Accepted : 2015.05.22
  • Published : 2015.05.31

Abstract

In this study, we developed a system to detect the various defects in the metallic objects using the phenomenon that the defects cause the changes of the natural resonant frequencies. Our system consists of a FFT Amp, an Auto Impact Hammer, a Hammer controller and a PC. Auto Impact Hammer creates vibrations in the metallic objects when tapped on the surface. These vibrational signals are converted to the voltage signals by an acceleration sensor attached to the metallic part surface. These analog voltage signals were fed into an ADC (analog-digital converter) and an FFT (fast fourier transform) conversion in the FFT Amp to obtain the digital data in the frequency domain. Labview graphical program was used to process the digital data from th FFT amp to display the spectrum. We compared those spectra with the standard spectrum to find the shifts in the resonant frequencies of the metal parts, and thus detecting the defects. We used PCB's acceleration sensor and TI's TMS320F28335 DSP (digital signal processor) to obtain the resolution of 2.93 Hz and to analyze the frequencies up to 44 kHz.

Keywords

References

  1. D. C. Park, "Future Trend & Suggestion for vehicle noise & Vibration development", Trans. Korean Soc. Automot. Eng., Vol. 33, No. 6, pp. 18-23, 2011.
  2. J. P. Park and Y. S. Choi, "Experimental analysis on brake squeal noise due to disk misalignment", Trans. Korean Soc. Automot. Eng., Vol. 12, No. 5, pp. 118-124, 2004.
  3. J. H. Lim, S. J. Cho, Y. S. Choi, S. J. Choi, and G. J. Choi, "Brake squeal noise due to disk run-out", Trans. Korean Soc. Automot. Eng., Vol. 13, No. 3, pp. 41-47, 2005.
  4. H. J. Cho, M. G. Kim, J. W. Maeng, and C. D. Cho "Analysis of the effect of mode shape on judder phenomenon in automotive disk brake", Trans. Korean Soc. Automot. Eng., Vol. 2, pp. 1056-1061, 2005.
  5. H. Y. Hwang, "Damage detection of structure based on natural frequency ratio measurements", J. of The Korea Society for Aeronautical and Space Sciences, Vol. 35, No. 8, pp. 726-734, 2007. https://doi.org/10.5139/JKSAS.2007.35.8.726
  6. H. I. Yoon and I. S. Son, "Dynamic behavior of rotating cantilever beam with crack", Trans. Korean Soc. Noise Vib. Eng., Vol. 15, No. 4, pp. 620-628, 2005. https://doi.org/10.5050/KSNVN.2005.15.5.620
  7. Y. S. ryong, "Non-Destructive Test", Sang Hakdang, Seoul, pp. 11-15, 2011.
  8. S. Seok and K. B. Kim "Recent Research Trend for Nondestructive Testing Technology", J. Korean Soc. Nondestruct. test., Vol. 24, No. 1, pp. 64-85, 2004.
  9. J. H. Kim, J. S. Kim, J. Lee, N. G. Kwag, and B. Y. Lee, "The basic study on the method of acoustic emission signal processing for the failure detection in the NPP structures", J. Korean Soc. Nondestruct. test., Vol. 29, No. 5, pp. 485-492, 2009.
  10. H, Y, Hwang and J, Y, Lee "Damage detection of structure based on frequency response functions", J. of The Korea Society for Aeronautical & Space Sciences, Vol. 28, No. 2, pp. 46-57, 2000.
  11. K. Hoon, S. H. Yoo, and S. W. Shin, "A simplified method for calculation of the natural frequencies using the stiffness contribution degree", J. Archit. Inst. Korea., Vol. 23, No. 8, pp. 3-10, 2007.
  12. K. C. Lim and S. H. Lim, "A study on torsional stiffness improvement of a vehicle", T. of Korean Institute of Fire Sci. & Eng., Vol. 11, No. 1, pp. 47-54, 1997.
  13. C. O. Kim and K. Y. Lim, "A study on the light control using DSP FFT processing module of audio and vibration signals", J. Korean Inst. Illum. Electr. Install. Eng., pp. 81-83, 2011.
  14. J. S. Lee and M. H. Sunwoo, "Design of new DSP instructions and their hardware architecture for high-speed FFT", I. J. Electronics. Information. Engineers., Vol. 39, No. 11, pp. 62-71, 2002.
  15. C. D. Lee and J. H. Kim, "Variability in the tensile properties of magnesium alloy on the microporosity variation", Trans. Korean Soc. Automot. Eng., Vol. 3, No. 6, pp. 1679-1684, 2007.

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