基于运动恢复结构的空间点定位方法  

Method of Space Point Positioning Based on Structure-from-Motion

作　　者：解则晓[1] 周作琪 Xie Zexiao;Zhou Zuoqi(College of Engineering,Ocean University of China,Qingdao,Shandong 266100,China)

机构地区：[1]中国海洋大学工程学院,山东青岛266100

出　　处：《激光与光电子学进展》2018年第8期364-371,共8页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(61571478)

摘　　要：针对大型工件难以进行全尺寸测量的问题,提出一种基于运动恢复结构的便携式空间点定位方法。首先使用具有身份唯一性的编码点粘贴在被测物体表面,实现各视图对应点的稳定匹配;接着为避免不同坐标系下位姿转换引起的累积误差,选定统一的坐标系,提出基于重心约束的基准定位算法;在此基础上,进一步确定相机运动参数的稳健性估计;最后利用多视图几何限制重建标志点的三维坐标,并用光束法平差对三维重建结果和相机内外参数进行全局优化。实验结果表明,该方法可实现大型工件的高精度测量,三维测量精度最大误差为0.133mm,平均误差为0.031mm,可满足工业现场对大型工件测量精度的要求。In view of the difficulty of full-scale measurement of large workpieces,aportable method of space point positioning based on structure-from-motion（SfM）is proposed.First,the coded target with unique identity is pasted on the surface of the measured object to achieve the stable matching of the corresponding points of each view.Then,to avoid the cumulative error caused by the position transformation in different coordinate systems,a unified coordinate system is selected,and a reference location algorithm based on the center of barycenter constraint is proposed.On this basis,the robust estimation of the camera motion parameters is further determined,and the 3D coordinates of the mark points are reconstructed by the multi view geometric constraints,and the global optimization of the 3 Dreconstruction results and the intrinsic and extrinsic parameters of the camera is carried out by the beam adjustment.The experimental results show that the method can achieve high precision measurement for large workpieces.The maximum error of 3D measurement is 0.133 mm and the average error is 0.031 mm,which can meet the requirements of industrial field measurement precision for large workpieces.

关 键 词：机器视觉 三维重建 运动恢复结构 重心约束 编码点 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]