The Research On Open Architecture Numerical Control Batch Welding System And Recognition Of Welding Line Based On Digital Image Processing

Chinese automotive industry is facing great challenges nowadays, the technology of automobile good-size moulds manufactures is an important part of automobile body manufacture technology, it also is a key of the ability of independent development in automotive production .To development a intelligent automatic welding equipment is a important part of moulds automatic manufactures.This paper explains the research on welding equipment, introduces Open Architecture Numerical Control software System to you , analyses the method of development. This paper also discusses the difficulties and the emphases in development of the PC embedded by NC, such as the DDA operating theorem of motion control card, multi-threaded technology and realization of real-time and database technology. It lies a emphasis on the steps and some key algorithms concerned with recognition of welding Line, such as Geometric Correction , Image Mosaic , Straight Line Extraction and Edge Detection. This paper introduces the Geometric Correction algorithm , which uses bilinear interpolation twice . Have analyzed their characters and applicatilities, we select the fittest one to the project among the several kinds of methods in Edge Detection. Two methods, the one is a new matching algorithm based on feature pixel-lined segment, the other is contact-match algorithm based on hierarchal pyramid are presented, you can utilize them in the Image Mosaic. Algorithm based on pyramid has a coarse-to-fine process. Fast speed , better anti-jamming and avoid knowing approximate matching area are the main good features of the algorithm. In the aspect of detection of the straight line, this thesis introduces Hough transform, which has been advanced in some of following aspect compared with it's general algorithm: the judgment of the connectivity of line , the detection of broken point, the complexity of algorithm. According above algorithm, we extract the welding lines from image and calculate their coordinates, it was proved a feasible way.On the base of theory analysis and research, I implemented a opened architecture numerical control welding system using Visual C++, which can detect welding lines assisted by person or extract welding lines from image. We can implement task of weld automatically and batchly,which lead to promote the productivity effectively, so it was put to use in industry.