车载抬头显示系统自由曲面反射镜点云匹配算法  

Point Cloud Matching Algorithm for Freeform Mirror of Vehicle Head up Display System

作　　者：袁封林 赵文川[2] 陈文静[1] YUAN Feng-lin;ZHAO Wen-chuan;CHEN Wen-jing(Department of Optic-Electronic,College of Electronics and Information Engineering,Sichuan University,Chengdu 610065,China;Institute of Optics and Electronics,Chinese Academy of Sciences,Chengdu 610209,China)

机构地区：[1]四川大学电子信息学院光电系,四川成都610065 [2]中国科学院光电技术研究所,四川成都610209

出　　处：《光学与光电技术》2021年第2期15-24,共10页Optics & Optoelectronic Technology

基　　金：国家重大仪器设备开发专项(2013YQ490879)资助项目。

摘　　要：车载抬头系统是未来车载仪表显示发展的必然趋势。针对在抬头显示系统自由曲面反射镜测量过程中不同区域特征相似、不易提取特征点,以及优化时易陷入局部最小值的问题,提出了一种高精度的三维点云与抬头显示反射镜面形模型匹配的方法,实现了高稳定性、高精度配准和误差评价。首先测量数据和模型数据转换成点云文件,经过三维旋转,使点云的法向量平行于Z轴;然后向不会造成重叠与遮挡的XOY平面投影;投影后,在二维平面内提取边缘,并提取边缘轮廓点,通过确定对应轮廓点计算旋转角度,在三维空间对点云数据旋转后,完成粗匹配,最后采用全局点云最小化目标函数完成精确匹配。该算法利用自由曲面反射镜的不规则边缘特征进行匹配,避免提取局部特征点,并且优化过程中不会陷入局部最小值,能够精确计算被测件的面形误差。Vehicle head-up system is the inevitable trend of the development of vehicle instrument display in the future.However,in the process of free-form mirror measurement in head-up display system,the features of different regions are similar,which leads to be difficult to extract feature points,and to fall into local minimum value during optimization. A high-precision method for matching the three-dimensional point cloud with the head-up display mirror surface model is proposed in this paper. Firstly,the measurement data and model are converted into point cloud files,and after threedimensional rotation,the normal vector of each point cloud is parallel to the Z axis,and then point cloud is projected to the XOY plane,which will not cause overlap and occlusion. Secondly,edge points are extracted in the two-dimensional plane,and the corner points of the edge are extracted. The rotation angle is calculated by determining the corresponding corner points,and then the corresponding rotation of point clouds is completed in the three-dimensional space. Thirdly,the rough matching is completed,and the fine matching is completed by minimizing the objective function. The algorithm in this paper uses the edge features of free-form surface mirrors for matching,avoids extracting local feature points,and does not fall into local minimums during the optimization process,and can accurately calculate the error of the tested surface.

关 键 词：机器视觉 点云配准 自由曲面反射镜 边缘特征 误差分布 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]