The Research Of The Geometric Feature Recognition System Of Correcting Pipe-End Based On Machine Vision

Since the first longitudinal-seam submerged arc welded (LSAW) pipes production line with JCO forming process was established in Julong Steel Pipe Co., Ltd, the unfinished pipe forming process and the correlated technology have been investigated by the researchers. Due to the key technology and the forming press from abroad, the systematical basic research on the forming process has not been conducted yet. And the pipe quality and processing parameters adjustment are conducted according to accumulated experience with the characteristics of large error, high personnel working strength and unstable production quality. As one of the effective method to improve the pipe-end quality, the technology of geometric feature recognition of the pipe-end is introduced to detect the pipe quality.Based on the research achievements of the intelligent control technology for the sheet metal bending, the key issue of the geometric feature recognition system of correcting pipe-end based on machine vision is resolved in this paper.Based on machine vision and sensor technology, the geometric feature recognition system of correcting pipe-end based on machine vision is developed, which can measure parameters of geometric feature of the pipe-end with contactless and high precision. The processing algorithms of image pre-processing and ellipse detection, which are simple, efficient and suitable for the pipe-end surface image, are studied in detail. Focused on the live condition, a new camera calibration method has been used to transform the angle in image into the actual angle.Based on these studies, the use of Visual C + + programming language developed the research of the geometric feature recognition system of correcting pipe-end based on machine vision, main contents: tube-end image processing, program development of detection and fitting of the ellipse. At last, employing the portble DAQ card and camera CCD and other hardware, the recognition system of geometric feature of correcting pipe-end based on machine vision is established.The physical simulated experiments have been conducted with the system, which showed that the system operated stably and was high-precision, the punch displacement predicted is reliable. The culmination of the research work is convenient and high-precision measurement of the pipe-end geometry.