基于三维模型生产大比例尺地形图的方法研究

The method of producing large- scale topographic map based on 3D model

为快速获取大比例尺地形图数字化成果,本文提出了一种基于三维模型技术的测量方法,详细介绍了技术流程、关键技术、精度分析等内容,并利用试验验证了该测量方法的精度。该试验采用已有三维模型数据,提取高密度地表点作为模型点云,随后对点云进行分类,提取地面点,通过设置折角、光滑系数等参数,生成光滑等高线,按要求自动提取高程点并套合三维模型验证其精度。试验结果显示,该方法可以得到更加光滑的等高线,其平面位置精度和高程精度均达到相关规范要求,并可显著提高地形图生产效率。

A 3D model-based surveying technology is proposed for rapid acquisition of large-scale digital topographic map in this paper, the technical process, key technologies, and accuracy analysis are introduced in detail, and the accuracy of surveying technology is illustrated by experiments. On the basis of existing data, high-density surface points are extracted as model point clouds in the experiments. Then the point clouds are classified and the ground points are extracted. Smooth contour lines are generated by setting parameters such as fold angle and smoothness coefficient, and the elevation points are automatically extracted as required and fitted into the 3D model to verify the accuracy. The experimental results show that the proposed method can generate smoother contour lines, and both the horizontal accuracy and vertical accuracy can meet the requirements of the relevant specifications, which helpful to improve the production efficiency of topographic maps.