地面三维激光扫描仪点间距测量精度研究

Research of point distance measurement accuracy of terrestrial 3D laser scanner

随着地面三维激光扫描技术的快速发展,将应用于更多行业尤其是工程测量方面,两点之间的距离是工程测量中的常用指标。由于工程应用对扫描点云精度要求越来越高,基于点云的点间距测量精度要求也在增高,研究地面三维激光扫描仪点间距测量精度有较高的实用价值。文中提出一种基于近景工业摄影测量技术的地面激光扫描仪点间距测量精度评定的方法,并针对实验中使用的平面圆形激光标靶,研究了基于平面拟合、空间投影等理论的标靶中心点坐标求取方法。特别是提出一种基于圆面几何特征的标靶中心点求取算法,并利用VC++2010平台开发程序实现,将文中的几何方法与常用的重心类标靶中心求取方法相对比,文中方法误差较小,在激光扫描仪离标靶测距较远,无法测得完整标靶,或是其他原因导致标靶部分数据缺失的时候可优先考虑。

The rapid development of terrestrial 3D laser scanning technology will be applied to more industries, especially engineering measurement, for which the distance between two points is a common indicator of engineering measurement. Because the engineering applications for point cloud precision increasingly demand, based point cloud point spacing measurement accuracy requirement will be improved, and the research on terrestrial 3D laser scanner point distance measurement accuracy has practical value. Based on Close range Photogrammetry Technology, this paper proposes a method to evaluate pointdistance measurement accuracy of the terrestrial 3D laser scanner, against the plane round target used in the experiment, and studies the method of calculating target center coordinates based on plane fitting and space projection theory. Based on round geometric features, another method is proposed to calculate the target center, with VC＋＋2010 platform develop program to achieve. Comparing the geometric method and the common center of gravity method, this method will smaller error, while the laser scanner is far away targets, it is unable to measure the complete target or causer the data of the target missing that will be given priority.