回转体零件内部误差工业CT图像测量  

Measurement method for internal error of rotary parts using industrial CT images

作　　者：江逸君 刘泽新 刘学栓 龙超 段黎明[1,2] 蔡玉芳[1,3] JIANG Yijun;LIU Zexin;LIU Xueshuan;LONG Chao;DUAN Liming;CAI Yufang(ICT Research Center,Key Laboratory of Optoelectronic Technology and Systems,Ministry of Education,Chongqing University,Chongqing 400044,China;College of Mechanical and Vehicle Engineering,Chongqing University,Chongqing 400044,China;College of Optoelectronic Engineering,Chongqing University,Chongqing 400044,China;Project Management Center,Equipment Department of Rocket Force,Beijing 100085,China)

机构地区：[1]重庆大学光电技术及系统教育部重点实验室ICT研究中心,重庆400044 [2]重庆大学机械与运载工程学院,重庆400044 [3]重庆大学光电工程学院,重庆400044 [4]火箭军装备部装备项目管理中心,北京100085

出　　处：《光学精密工程》2025年第4期557-567,共11页Optics and Precision Engineering

基　　金：国家重点研发计划资助项目(No.2022YFF0706400);国家自然科学基金资助项目(No.52075057)。

摘　　要：针对回转体零件内部误差测量难题,利用工业CT无损、可检测内部结构的优势,由工业CT图像实现了回转体零件内部误差的测量。首先,计算回转体轴线参数,并将轴线参数和罗德里格公式引入区域生长法中,提升了三维点云分割精度。然后,建立几何模型的目标函数,采用最小二乘线性拟合获得几何模型的初始参数,进一步采用Levenberg-Marquart非线性拟合求解几何模型的最优参数。最后,根据建立的几何模型计算零件内部的形位误差。实验结果表明,本文提出的点云分割方法精度优于其他方法;表面重建方法相比RANSAC算法稳定性更好;形位误差计算精度相比商用VG软件精度更高,圆柱度提高8.5%,同轴度提高21.1%,垂直度提高4.1%,圆锥公差计算结果都在设计值范围内,满足误差测量工程需求。To address the issue of internal error measurement for rotary components,this paper exploited the advantages of industrial CT,which is non-destructive and capable of detecting the internal structure,and achieved the internal error measurement of rotary components through industrial CT images.Firstly,the axis parameters of the rotary body were calculated,and these parameters and Rodrigues’s formula were incorporated into the region growing method to enhance the accuracy of 3D point cloud segmentation.Subsequently,the objective function of the geometric model was established,and initial parameters of the geometric model were obtained through least squares linear fitting.Further,the optimal parameters of the geometric model were solved using Levenberg-Marquardt nonlinear fitting.Finally,the geometric model was utilized to compute the shape and position errors of the parts.Experimental results demonstrate the superiority of the proposed point cloud segmentation method in terms of accuracy when compared to other methods.Additionally,the surface reconstruction method exhibits better stability than the RANSAC algorithm.Compared with commercial VG software,the accuracy of shape and position error calculation is higher,with an increase of 8.5%in cylindricity,21.1%in coaxiality,and 4.1%in verticality.Moreover,the cone tolerance calculation yields results within the design specifications,which satisfying the requirements of error measurement engineering.

关 键 词：计算机断层成像 点云分割 表面重建 误差测量 

分 类 号：TP394.1[自动化与计算机技术—计算机应用技术] TH691.9[自动化与计算机技术—计算机科学与技术]