基于机载LiDAR数据测绘大比例尺地形图的研究与应用——以山地城市为例

传统大范围的大比例尺地形图测制多采用航测的方法,但基于航摄影像匹配的航测方法本身存在着一定的局限性,机载Li DAR通过激光回波获取信息,激光具有一定的穿透性,在植被覆盖的区域也能获取一定数量的地面反射激光点;激光点云本身记录了三维坐标信息,各种物体顶部的激光点不存在投影差的问题,Li DAR数据的特点正好能弥补航摄影像的不足之处。本文通过研究基于机载Li DAR数据配合高分辨率数字正射影像在山地城市测制大比例尺地形图,探索出一套生产方法流程,以重庆测区为例,分析了该方法的可行性并对测图成果精度进行了系统性分析,结果表明,本试验中要素精度和DEM精度可以达到1∶2 000的测图要求。

Research and Application on the Large Scale Topographic Map Surveying Based on Airborne-LiDAR data-A Case Study at Mountain City

Traditional large scale topographic mapping uses aerial photography,however,this method is limited to several external factors,for instance,the density of vegetation coverage,the photogrammetry projection error and the image shades,etc. Airborne-LiDAR uses Laser shots to fetch the information on earth. The Laser point holds three-dimension-al information and intensity of echo,this characteristic just makes up the short come of Traditional method. This article does research on large scale topographic mapping in mountain city using airborne-LiDAR data. In this case study,we found a normal production process and analyzed the accuracy of the results. The conclusion shows the result accuracy can be used for 1 : 2000 scale topographic mapping.