A Method for Determining the Center Position of Tube Holes Based on Improved Hough Gradient Circle
In the process of eddy current testing in the heat transfer tubes of nuclear power evapora-tors,there is a need to improve the accuracy of the crawlers in locating the center of the heat transfer tube holes to be tested.This paper proposes a machine vision positioning method based on the Hough gradient circle and least squares fitting to accurately locate the center of the heat transfer tube hole and fit the hole circle.The method first performs Canny edge detection and Hough gradient circle detection on the test im-age,and then iterates through each edge point in the Canny edge map.Based on the distance between the edge point and the center of all Hough gradient circles,the method determines whether the calculated re-sult is within the error range of the radius of the Hough gradient circle and casts a vote accordingly.After iterating through all the edge points,the effective edge point set is determined based on the Hough gradient circle with the highest number of votes,and the circle center and radius are finally fitted using the least squares method.Compared with the traditional Hough gradient circle detection method,the experimental results show that this method has high positioning accuracy,strong anti-interference ability,and strong generalization ability,and has the function of high-precision and efficient positioning detection in field en-vironments.
center positioning of the tube holecircle fittingHough gradient circle detectionleast square method
国家科技期刊平台
NSTL
万方数据
维普
