| Calipers have been commonly used by the majority of domestic manufacturers as the method to measure and detect thickness, section, inner and outer radius of O-shape sealing rubber ring. However, this measurement has a disadvantage of large error, low detection efficiency, meanwhile detection precision and speed also could not reach the requirements of manufacturing. The machine vision technology, owing to the advantages of non-contact, fast speed, and high detection precision, has been valued by more and more manufacturers. In this paper, we designed a set of on-line detection system for O-shape sealing rubber ring based on machine vision technology, its main contents were as follows:1. Formulated systematic design scheme, designed O-shape seal rubber ring detection device, and constructed experimental hardware platform.2. Through the experiments, we verified the classical algorithms of image preprocessing, image segmentation, edge detection, etc. After a comparative analysis of merits and inferiorities between different algorithms, we present the method of Curvelet hybrid filter adapt to the project. It's proved that this method could effectively remove the mixed noise in image and increase the SNR. To segment image by the algorithm Otsu and detect the edge by the Morphology, it can extract the edge information well.3. According to the detect demand for rubber ring, we used the edge detection pixel scanning method to detect thickness, Hough transform for center location and diameter measurements, rapid formation of the template parameters for defect detection.4. We used DSP technology to improve the efficiency of detection system, complete the transplant of image processing algorithms from DSP to PC, detect the system and analyze error. |
