C-V模型与工业CT相结合的几何测量方法

针对工业生产中复杂封闭内腔几何尺寸很难测量的问题,提出一种基于C-V模型的工业CT几何测量方法.首先利用C-V模型提取目标边缘坐标点的有序链码,然后利用Green定理和欧氏距离公式计算目标区域的面积和周长.在提取目标边缘坐标点的步骤中,把边缘灰度先验知识融入C-V模型以提高测量精度;在计算目标区域的面积和周长的过程中,合理地选择目标边缘有序坐标点和插值有序坐标点,再一次提高几何测量精度.实验结果表明,与2DFacet模型测量方法相比,文中方法测量精度约提高1个数量级;并已将该方法应用于实际中.

Geometric Measurement Method Integrating C-V Model and Industrial CT

To tackle the difficulty in measuring complex enclosed inner cavity in industry,a geometric measurement method integrating industrial CT(Computed Tomography) and C-V model is presented.In this method,C-V model is used to extract ordered chain of target edge coordinates.And then,Green theorem and Euclidean distance formula are applied to compute the area and perimeter of target region.To extract target edges in C-V model,the prior knowledge of edge grey intensity is used to improve the accuracy of measurement in this paper.For computing the area and perimeter of the target region,ordered coordinates of the target edges are selected reasonably and interpolation of the ordered coordinates is done,which further improves the accuracy of measurement.The experiment results show that,compared to the measurement method with 2D Facet model,the accuracy with improved measurement method increases about one order of magnitude.Besides,improved measurement method has been used in engineering.