Abstract:As a consumable part of drilling technology, twist drill plays an important role in modern manufacturing industry, and its output is increasing year by year. While process detection technology plays an important role in ensuring drilling effect. The blade width of twist drill affects the drilling quality and processing time. In order to reduce the labor cost, a detection method of blade width based on binarization is proposed. Firstly, the target edge is sharpened, and then the edge information is extracted by Butterworth high-pass filtering. Secondly, through the improved Otsu binarization algorithm, the suspected edge points are threshold segmentation and the coordinates of the edge points are obtained. Again, the Levenberg-Marquardt algorithm is used to fit the points near the edge, so as to get the edge band width curve and its inflection point, and get the data of edge band width of twist drill. Finally, the contrast experiment was carried out, and the untreated HSS blade image with a diameter of 9mm was processed by LM method, and the blade width was 1.467 mm, and the measurement error was 0.467mm.. The improved measurement result is 0.853 mm and the measurement error is 0.147 mm.