A Study on the Vision Sensor System for Tracking the I-Butt Weld Joints

I형 맞대기 용접선 추적용 시각센서 시스템에 관한 연구

  • Bae, Hee-Soo (Dept.of Mechanical Engineering, Graduate School of Yeungnam University) ;
  • Kim, Jae-Woong (School of Mechanical engineering, Yeungnam University)
  • 배희수 (영남대학교 대학원 기계공학과) ;
  • 김재웅 (영남대학교 공과대학 기계공학부)
  • Published : 2001.09.01

Abstract

In this study, a visual sensor system for weld seam tracking the I-butt weld joints in GMA welding was constructed. The sensor system consists of a CCD camera, a diode laser with a cylindrical lens and a band-pass-filter to overcome the degrading of image due to spatters and arc light. In order to obtain the enhanced image, quantitative relationship between laser intensity and iris number was investigated. Throughout the repeated experiments, the shutter speed was set at 1-milisecond for minimizing the effect of spatters on the image, and therefore most of the spatter trace in the image have been found to be reduced. Region of interest was defined from the entire image and gray level of searched laser line was compared to that of weld line. The differences between these gray levels lead to spot the position of weld joint using central difference method. The results showed that, as long as weld line was within $^\pm$15$^\circ$from the longitudinal straight fine, the system constructed in this study could track the weld line successful1y. Since the processing time reduced to 0.05 sec, it is expected that the developed method could be adopted to high speed welding such as laser welding.

Keywords

References

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