基于扫描点云数据的零部件边缘轮廓提取技术

针对目前大型零部件边缘轮廓线提取效率低的问题,提出一种基于扫描点云数据的零部件边缘轮廓提取技术。该技术从边缘轮廓线的形成方式出发,通过分析边缘轮廓线垂直截面线的分布特征,定义了模式向量表征屋脊型和折线直线-直线相交型截面线。提取过程主要包含截面线数据的获取、截面线类型的识别和边缘轮廓线数据的提取这3个步骤。为获取边缘轮廓线的截面线数据,构造了初始边缘轮提线,并沿初始轮提线构造垂直万向切片。万向切片与网格化云云数据的交,云卩为截面线数据。定义了基于相邻点法向夹角的模式向量,用以识别截面线的类型。针对折线型和屋脊型截面线数据提出拟合求交法和重心计算法提取其上的边缘轮提线数据云。开展试验验证提取技术的有效性和精度,结果表明所述方法的边缘轮廓线提取准确度可达到±0.2 mm。

Extraction of Points on Edge Contours From Scanned Point Cloud

In order to solve the problem of low extraction efficiency of edge contour extraction from large-scale parts,an extraction technology based on scanned point cloud data is proposed.Starting from the formation of edge contour line,the mode vector is defined to represent the roof type and the broken line-line intersection type section line by analyzing the distribution characteristics of vertical section line of edge contour line.The extraction process mainly includes three steps,namely section line data acquisition,section line type recognition and edge contour line data extraction.In order to obtain the section line data of the edge contour line,the initial edge contour line is constructed,and the vertical universal slice is constructed along the initial contour line.The intersection of the universal slice and the gridded point cloud data is the section line data.Pattern vector based on the normal angle of adjacent points is defined to identify the type of section line.For the broken line and ridge section line data,the fitting intersection method and gravity center calculation method are proposed to extract the edge contour line data points.Experiments were carried out to verify the effectiveness and accuracy of the extraction technology.The results show that the accuracy of edge contour extraction can reach ±0.2 mm.