|
Small parts is an important part of a variety of devices, and its direct impact on the quality of the normal operation of the equipment and the economic efficiency of enterprises, small parts detection method has important significance. Industrial detection of small parts, the use of simple manual inspection speed is slow, low accuracy, and small parts damage detection process, therefore a need for a high-precision, real-time non-contact detection, line detection method based on visual inspection technology detection speed, high precision, non-contact automatic detection, save manpower, reduce errors caused by human factors. Visual inspection to detect small part appearance quality detection method based on the above-mentioned characteristics. Detection by the image of the high-speed CCD acquisition parts the DSP chip TMS320DM643 on image denoising, enhanced, rotation, edge extraction, recognition and judgment, and the results by controlling the port output to the control mechanism, sorting operation. Research image processing image processing technology, using median filter for image denoising, gray-scale transformation of image enhancement, and prominent feature of interest in the image, more conducive to observation of the target object. CCD acquired images, the target object placement is not level, to make a follow-up treatment more convenient to deal with image rotation, first locate the target area, and then to polar coordinate rotation method to find the smallest rectangle and then rotate the image, making the image The target object is placed horizontally. 3, contour tracking image edge detection, the first search starting point, to scan its adjacent points from the starting point, find the edge point, then this point as a new starting point for the next edge point from its neighborhood search elements to forth the outline of the image of the object chain code. 4 proposed using the chain code table thread profile tracking and identification. First, according to the thread characteristics of small parts, corresponding to the law of the standard chain code table found in the chain code table of the target object obtained, to determine the number of the thread as well as a single threaded chain code value, and then using the standard single threaded rising and falling similar to the principle of the single threaded to judge, in accordance with the principles of the rising and falling edges of each thread of the number of chain codes and similar at the same time to determine the thread profile is uniform, and to determine that the parts are qualified. A large number of experiments under different conditions, a variety of screws, the experimental results show that: this method is accurate and reliable, efficient, fast and has good flexibility, suitable for high-speed line detection of different models screw.
|