Visual positioning of rectangular lead components based on Harris corners and Zernike moments  

作　　者：王祖进 黄筱调 

机构地区：[1]Department of Mechanical and Power Engineering, Nanjing Tech University

出　　处：《Journal of Central South University》2015年第7期2586-2595,共10页中南大学学报（英文版）

基　　金：Project(51175242)supported by the National Natural Science Foundation of China;Project(BA2012031)supported by the Jiangsu Province Science and Technology Foundation of China

摘　　要：With the increasing necessities for reliable printed circuit board(PCB) product, there has been a considerable demand for high speed and high precision vision positioning system. To locate a rectangular lead component with high accuracy and reliability, a new visual positioning method was introduced. Considering the limitations of Ghosal sub-pixel edge detection algorithm, an improved algorithm was proposed, in which Harris corner features were used to coarsely detect the edge points and Zernike moments were adopted to accurately detect the edge points. Besides, two formulas were developed to determine the edge intersections whose sub-pixel coordinates were calculated with bilinear interpolation and conjugate gradient method. The last experimental results show that the proposed method can detect the deflection and offset, and the detection errors are less than 0.04° and 0.02 pixels.With the increasing necessities for reliable printed circuit board（PCB） product, there has been a considerable demand for high speed and high precision vision positioning system. To locate a rectangular lead component with high accuracy and reliability, a new visual positioning method was introduced. Considering the limitations of Ghosal sub-pixel edge detection algorithm, an improved algorithm was proposed, in which Harris corner features were used to coarsely detect the edge points and Zernike moments were adopted to accurately detect the edge points. Besides, two formulas were developed to determine the edge intersections whose sub-pixel coordinates were calculated with bilinear interpolation and conjugate gradient method. The last experimental results show that the proposed method can detect the deflection and offset, and the detection errors are less than 0.04° and 0.02 pixels.

关 键 词：visual positioning Harris corners Zernike moments edge detection sub-pixel image registration 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]