利用机载LiDAR数据重建大型复杂立交桥三维模型  

Three-Dimensional Reconstruction of Large Multilayer Overpass Using Airborne LiDAR Data

作　　者：伍阳[1,2] 程亮[1,2] 陈焱明[1,2] 李满春[1,2] WU Yang CHENG Liang CHEN Yanming LI Manchun(Department of Geographic Information Science, Nanjing University, Nanjing 210023, China Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, Nanjing 210023, China)

机构地区：[1]南京大学地理信息科学系,南京210023 [2]江苏省地理信息技术重点实验室,南京210023

出　　处：《地球信息科学学报》2016年第9期1249-1258,共10页Journal of Geo-information Science

基　　金：国家自然科学基金项目(41371017;41001238)

摘　　要：立交桥三维模型在交通导航、景观设计等方面具有重要价值。机载Li DAR平台能够快速、准确地获取地物三维点云,有助于立交桥的提取与重建。本文提出了一种基于机载Li DAR数据的大型立交桥三维模型重建方法。该方法首先从原始数据中提取立交桥点云,然后构建三维网格并根据连通性对立交桥点云进行分割,将连通桥面进一步分割为无分叉或交汇结构且宽度保持一致的"结构单元",接着利用道路中心线的连续性对立交桥遮挡部分进行修复,并结合桥面中心线和宽度信息对桥面进行重建,最终获得完整的立交桥三维模型。为了验证方法的有效性,本文选取了2个立交桥数据进行实验。结果表明,重建模型的正确率和完整率达均到90%以上,质量较好。本文方法能够取得较好的大型立交桥三维重建效果。Three-dimensional （3D） model data of overpasses is significant for traffic navigation, landscape design, and many other applications. In this study, we explore the potential of using airborne light detection and ranging （LiDAR） data for the 3D recon- struction of large muitilayer overpasses. To reduce the technical difficulty of this 3D reconstruction process, we propose a concept of ＂structure unit＂. The ＂structure unit＂ represents a contiguous object with a consistent width, but does not include the bifurcation and/or intersection structures. A new technical framework, based on the structure units, is proposed to reconstruct the 3D models of large multi-layer overpass using the airborne LiDAR data. First, the overpass points are extracted from the raw LiDAR data by us- ing a Reversed Iterative Mathematic Morphological （RIMM） method and inputting the area of overpass. Then, the hierarchal seg- mentation strategy, including the connectivity-based segmentation and the determination of structure units, is used to determinate the structure units from the overpass points. The central line of each structure is derived by the binarization and vectorization opera- tions. And the obscured structures are detected and restored based on the central lines of the overpass. Finally, the complete 3D mod- el of the overpass can be obtained by using the complete central line and the corresponding width value. Experiments were carried out to evaluate the validities of the proposed method on two different overpasses. The completeness rates of the 3D models of over- passes A and B are 92.77% and 94.58%, respectively. And the correctness rates of the 3D models of overpasses A and B are 98.84% and 98.97%, respectively. The experimental results indicate that the proposed method can provide satisfactory 3D models for large complex overpasses, and is capable to restore the occluded structures with high quality result.

关 键 词：LIDAR 立交桥 三维重建 结构单元 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]