TERRESTRIAL LASER SCANNING IN ARCHITECTURAL HERITAGE – DEFORMATION ANALYSIS AND THE AUTOMATIC GENERATION OF 2D CROSS-SECTIONS
TERRESTRIAL LASER SCANNING IN ARCHITECTURAL HERITAGE – DEFORMATION ANALYSIS AND THE AUTOMATIC GENERATION OF 2D CROSS-SECTIONS
复制标题
建筑遗产中的地面激光扫描 - 变形分析和自动生成 2D 横截面
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
D. Roose
中科院分区：
文献类型：
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作者：
B. V. Genechten;M. S. Quintero;T. Demeyere;S. Herinckx;L. Schueremans;D. Roose
由于其速度和准确性，地面激光扫描在建筑和文化遗产领域越来越重要。激光扫描仪是一种视场设备，可以对物体的几何形状进行密集的逐点采样。本文的第一部分讨论了激光扫描是否产生足够准确的结果，用于变形监测的历史结构的问题。使用圬工拱的测试设置准备在不同的情况下进行了模拟。在不同的时间扫描的结构，同时移动其一个腿和不同的扫描分辨率的精度和变形的可检测性的影响进行了测试。使用不同的设置，测试了不同目标配置对准确度的影响，特别是到扫描仪的方向和距离。在第二部分中，提出了两个原型算法的基础上点云的横截面的自动生成。第一种方法是基于点splats。点splats是一种替代网格的表面一样重建的点云。它们的主要优点是计算成本低，能够准确地表示尖锐的边缘和细节。从我们的算法获得的横截面进行比较，从基于网格的表面表示获得类似的横截面。第二种方法基于稳健统计技术将切片点云分割成无离群点的聚类。通过拟合参数模型并使用移动最小二乘法计算残差来生长集群。该过程生成具有尖锐不连续表示的分段光滑横截面。为了证明该算法的可用性，从该算法获得的横截面进行比较，从基于网格的表面表示获得类似的横截面。* 通讯作者
Thanks to its speed and accuracy, terrestrial laser scanning is gaining importance in the field of architectural and cultural heritage. Laser scanners are field-of-view devices that offer a dense point-wise sampling of an object‟s geometry. The first part of this article addresses the question whether laser scanning produces sufficiently accurate results to be used for deformation monitoring of historical structures. A test setup using a masonry arch was prepared in which different scenarios were simulated. The structure was scanned at different times while moving one of its legs and the influence of different scan resolutions on the accuracy and the detectability of deformations were tested. Using a different setup, the influence on accuracy of different targets configurations, in particular orientations and distances to the scanner were tested. In a second part, two prototype algorithms are presented for the automatic generation of cross sections based on point clouds. The first method is based on point splats. Point splats are an alternative for meshes for the surface-like reconstruction of point clouds. Their main advantages are the low computational cost and the ability to give an accurate representation of sharp edges and details. The cross sections obtained from our algorithm are compared to similar cross sections obtained from a mesh based surface representation. The second proposed method segments a sliced point cloud into outlier-free clusters based on techniques from robust statistics. The cluster is grown by fitting a parametric model and computing the residuals using a moving least squares approach. This procedure generates a piecewise smooth cross-section with sharp discontinuity representations. In order to prove the usability of the algorithm, the cross sections obtained from this algorithm are compared to similar cross sections obtained from a mesh based surface representation. * Corresponding author