标题: 三维雷射扫瞄仪点云资料密度对最适平面求解精度影响
The Relationship Between Point Cloud Density and Fit-plane Accuracy of 3D Laser Scanners
作者: 徐元俊
Yuan-Chun Hsu
陈春盛
Chun-Sung Chen
土木工程学系
关键字: 三维雷射扫瞄仪;点云密度;重新取样;3D Laser Scanner;Point cloud density;Resampling
公开日期: 2005
摘要: 三维雷射扫瞄仪是一种能在短时间内快速获取大量高精度三维点位相对坐标的仪器。它详细地记录了待测物体及其周遭景物的三维地表资讯。不同于以往测量仪器“点”的测量,而是以“面”的方式对周遭景物及待测物进行整体扫瞄。三维雷射扫瞄仪所得的初步资料是均匀密布于被测物体表面的三维点云资料,它仍是属于隐性资料,对于被测物并非显性描述,对大多数的工程测量应用而言,需要将点云资料进行模型化的处理,以便获得被测物之物件式或图元式的显性描述。
空间中的几何资讯一般为物体的点、线、面,而三维雷射扫瞄仪所获得的点云资讯并无法直接获得被测物表面的几何资讯,虽然某些仪器厂商提供了原厂觇标以供捕捉特定点位的精确三维坐标,但是在实际外业工作上,除了布设觇标的困难,如:高楼外侧、建物边角等;此外,具文化价值的传统古迹建物,也不容许有破坏性布标工作的进行,因此如何利用既有的点云资料来获取被测物体的表面资讯也更显得重要。
本研究所使用之点云资料是以Trimble GS200型三维雷射扫瞄仪所得地面结构物表面之点云资料。利用最小二乘法进行点云最适平面的计算工作与精度分析,并利用不同的取样方式,减少原始点云群资料,分析其成果与原始点云资料之差异,以期透过重新取样的方式减少点云资料,进而增进计算速度。
The 3D Laser Scanner is a kind of instrument that can obtain a large number of high-accuracy three-dimensional relative coordinates in a short time. The original point cloud data of objects are implicit not explicit. As to the applications to engineering, we have to modeling the point cloud data so as to get the explicit description of objects.
The geometry information of an object in the space are generally points, lines, and surfaces. These information can’t directly obtained from point clouds, though some instrument manufacturers have offered targets for catching the perfect three-dimensional coordinates, but in the field works, it is quite difficult. How to utilize the point clouds to obtain the geometry information of object surfaces is more important.
The test data applied in this research is scanned by Trimble GS200 3D Laser Scanner. Utilize Least-Square method to calculate the fitting planes and use different resampling methods to reduce the original point cloud data to understand the differences and improve calculate speed.
URI: http://140.113.39.130/cdrfb3/record/nctu/#GT009316578
http://hdl.handle.net/11536/78704
显示于类别:Thesis