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멀티카메라 비전시스템을 위한 산업용 PC와 PLC간 제어 방법 개발

The implementation of interface between industrial PC and PLC for multi-camera vision systems

  • 김현수 (울산과학대학교 기계공학부)
  • Kim, Hyun Soo (School of Mechanical Engineering, University College of Ulsan)
  • 투고 : 2015.12.02
  • 심사 : 2016.01.05
  • 발행 : 2016.01.31

초록

머신비전은 고속화된 자동화 생산 시스템의 품질 검사 방법으로 널리 활용되어 왔다. 본 연구에서는 멀티카메라를 사용하여 PC와 PLC 간 제어를 통해 용접부위의 치수를 실시간으로 측정하여 검사하는 머신비전 시스템을 개발하였다. 제안한 검사시스템은 맞대기 용접부위의 길이와 폭을 측정하여 용접부의 치수 균일성을 검사하도록 설계하였다. 광학계 및 물류는 병렬제어를 위해 PC와 PLC 간 TCP/IP 멀티쓰레딩 통신기법을 적용하였다. 금속재료의 반사 특성을 고려하여 용접비드의 형태나 용접시 발생하는 그을음에도 균일하게 검사부위의 영상획득이 가능한 동축조명계를 적용하였고, 검사 알고리즘은 OpenCV 라이브러리를 사용하여 용접치수검사에 맞게 개발하였다. 제작한 시스템을 실제 전자부품의 용접 자동화 라인에 설치하여 시스템의 작동오류 및 검사 성능을 검증한 결과, 요구되는 기능 및 검사 성능을 모두 성공적으로 수행하였다.

One of the most common applications of machine vision is quality inspections in automated production. In this study, a welding inspection system that is controlled by a PC and a PLC equipped with a multi-camera setup was developed. The system was designed to measure the primary dimensions, such as the length and width of the welding areas. The TCP/IP protocols and multi-threading techniques were used for parallel control of the optical components and physical distribution. A coaxial light was used to maintain uniform lighting conditions and enhance the image quality of the weld areas. The core image processing system was established through a combination of various algorithms from the OpenCV library. The proposed vision inspection system was fully validated for an actual weld production line and was shown to satisfy the functional and performance requirements.

키워드

참고문헌

  1. Y. K. Cho, Seok. J. Ka, J. S. Kim, M. W. Cho and W. H. Choi "LED Die Bonder Inspection System Using Integrated Machine Visions," Journal of the Korea Academia-Industrial cooperation Society, Vol. 14, No. 6 pp. 2624-2630, 2013. DOI: http://dx.doi.org/10.5762/KAIS.2013.14.6.2624
  2. H. K. Park, "Development on the Process Control System for Full Gate Visual Test of LCD Manufacturing Process," Journal of the Korea Academia-Industrial cooperation Society, Vol. 10, No. 7 pp. 1725-1728, 2009. DOI: http://dx.doi.org/10.5762/KAIS.2009.10.7.1725
  3. J. H. Bae, S. W. Ra, P. S. Yu and S. G. Kim, "Development of Automatic Inspection System for Lead Screw of Computer," Journal of the Korea Academia-Industrial cooperation Society, Vol. 11, No. 11 pp. 4115-4120, 2010. DOI: http://dx.doi.org/10.5762/KAIS.2010.11.11.4115
  4. S. J. Kim and S. C. Lee, "Development of Inspection System for Surface of a Shock Absorber Rod using Machine vision," Journal of the Korea Academia-Industrial cooperation Society, Vol. 15, No. 6 pp. 3416-3422, 2014. DOI: http://dx.doi.org/10.5762/KAIS.2014.15.6.3416
  5. B. Jang, "Design on Automatic Vision System for Fast Alternator Spool Inspection," Journal of the Korea Academia-Industrial cooperation Society, Vol. 11, No. 11 pp. 4145-4150, 2010. DOI: http://dx.doi.org/10.5762/KAIS.2010.11.11.4145
  6. N. S. Andres and B. Jang, "Development of a machine vision system for automotive part car seat frame inspection," Journal of the Korea Academia-Industrial cooperation Society, Vol. 12, No. 4 pp. 1559-1564, 2011. DOI: http://dx.doi.org/10.5762/KAIS.2011.12.4.1559
  7. E. S. Jeon, H. H. Kang and D. H. Lee, "Development of Measurement System for Welding Bead Shape using LabVIEW," Journal of the Korea Academia-Industrial cooperation Society, Vol. 8, No. 2 pp. 189-194, 2007.
  8. J. I. Lee, "The Weldability Estimation for the Purpose of Real-Time Inspection and Control," Journal of the Korea Academia-Industrial cooperation Society, Vol. 9, No. 3 pp. 605-610, 2008. https://doi.org/10.5762/KAIS.2008.9.3.605
  9. S. Cho, S. H. Sim and E. Kim, "On-site Performance Evaluation of a vision-based displacement measurement system," Journal of the Korea Academia-Industrial cooperation Society, Vol. 15, No. 9 pp. 5854-5860, 2014. DOI: http://dx.doi.org/10.5762/KAIS.2014.15.9.5854
  10. S. B. Lee, T. H. Park and K. S. Han, "Implementation of vision inspection library for PLC applications," CICS(Conference on Information and Control System) 2013, pp. 13-15, 2013.