Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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A Study on the Digital Filter and Wavelet Transform of Monitoring for Laser Welding

레이저 용접 모니터링에 적합한 디지털 필터와 웨이블렛 변환 방법에 관한 연구

  • Kim, Do Hyoung (Department of Applied Photonic Engineering, Chosun Univ.) ;
  • Shin, Ho Jun (Department of Shipbuilding and Machine, Jeonnam Provincial College) ;
  • Yoo, Young Tae (Department of Mechatronics Engineering, Chosun Univ.)
  • 김도형 (조선대학교 광응용공학과) ;
  • 신호준 (전남도립대학교 조선기계과) ;
  • 유영태 (조선대학교 메카트로닉스공학과)
  • Received : 2012.07.31
  • Accepted : 2012.10.22
  • Published : 2013.01.01
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Abstract

We present an innovative real-time laser welding monitoring technique employing the correlation analysis of the plasma plume optical emission generated during the process. The plasma optical radiation emitted during Nd:YAG laser welding of S45C steel samples has detected with a Photodiode and analyzed under different process conditions. The discrete DC voltage difference, filter methods and wavelet transform has been used to decompose the optical signal into various discrete series of sequences over different frequency bands. Considering that wavelet analysis can decompose the optical signals, extract the characteristic information of the signals and define the defects location accurately, it can be used to implement process-control of laser welding.

Keywords

References

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Cited by

  1. Defect Detection in Laser Welding Using Multidimensional Discretization and Event-Codification vol.32, pp.11, 2015, https://doi.org/10.7736/KSPE.2015.32.11.989