曾月鹏

摘 要： 传统逆向工程重构系统进行逆向工程重构时，由于Image ware软件无法处理数据规模较大的点云数据，容易出现点云同三维曲面的吻合度较差，工件曲面的三维重构精度低。设计基于三维图像的逆向工程重构系统，通过系统输入/输出文件格式、平滑滤波、边缘检测和阈值分割系统等软件功能，将三维图形进行重构与显示得到三维图像的测量与输出结果，对输出结果进行矢量和格式转换实现CAD三维建模。三维数字化尺寸检测将三维模型的测量点云位置与物体重合，对测量点云进行旋转和平移的操作使其能够同三维曲面模型达到最高程度的吻合，在三维空间对三维曲面进行取样，获取各点法向量，将点云数据与法向量结合，实现工程工件曲面的三维重构。实验结果表明，所设计系统可显著提高点工件点云数据处理结果的清晰度，工件三维曲面拟合精度较高。

关键词： 三维图像； 逆向工程； 重构系统； 数字化尺寸检测； 点云数据； 曲面

中图分类号： TN911.73?34； TP391.41 文献标识码： A 文章编号： 1004?373X（2018）20?0168?04

Abstract： As the Image ware software cannot process large?scale point cloud data， problems of poor goodness of fit between the point cloud and 3D curved surface， and low 3D reconstruction accuracy for curved surfaces of the workpiece are likely to occur during the reverse engineering construction of the traditional reverse engineering reconstruction system. Therefore， a reverse engineering reconstruction system based on 3D images is designed. 3D graphics are reconstructed and displayed by utilizing the system′s software functions such as output of input file format， smooth filtering， edge detection and threshold segmentation， so as to obtain the measurement and output results of 3D images. Vector and format conversions are conducted for the output results to achieve CAD 3D modeling. The measured point cloud location of the 3D model is overlapped with the object by utilizing the 3D digital size detection. The rotation and translation operations of the measured point cloud are conducted to enable it to achieve highest degree of goodness of fit with the 3D curved surface model. Sampling of 3D curved surfaces is conducted in 3D space to obtain the normal vector of each point. 3D reconstruction for curved surfaces of the engineering workpiece is realized by combining the point cloud data with normal vector. The experimental results show that the designed system can significantly improve the resolution for point cloud data processing results of the workpiece， and has high fitting accuracy for 3D curved surfaces of the workpiece.

Keywords： 3D image； reverse engineering； reconstruction system； digital size detection； point cloud data； curved surface

逆向工程在许多领域中都有着极其重要的作用，其不但能够缩短产品开发的时间，也能够检测现有的产品、修复损坏的产品、检测产品的实际数据与设计数据之间的误差[1]。传统基于Image ware的逆向工程重构系统进行逆向工程重构时，容易出现点云数据处理结果周围存在大量噪声干扰问题，导致点云同三维曲面的吻合度较差，工件曲面的三维重构精度低。……