In areas covered by vegetation, large-scale topographic mapping by UAV oblique photogrammetry normally obtain elevations from vegetation instead of ground points, resulting in lower elevation precision. This study developed an precision improvement grid algorithm and associated SOP for large-scale topographic surveying and mapping in vegetation coverage areas by UAV oblique photogrammetry. The procedures of generating a three-dimensional model for topographical surveying was proposed using Guanlang project as an experimental case study. The UAV flight route and the course overlap and side overlap of UAV oblique photogrammetry were designed, and the image control point layout in the experimental field was carried out. CTI T3 high-precision intelligent RTK was used for image control point measurement. A grid algorithm based on elevation maps was developed and validated in the Guanlang experimental field to improve the elevation precision in vegetation coverage areas.

在植被覆盖的地区，通过无人机倾斜摄影测量法进行的大规模地形图通常会从植被而不是地面获取标高，从而降低标高精度。这项研究开发了一种精确度改进的网格算法和相关的SOP，用于通过UAV斜向摄影测量法对植被覆盖区进行大规模地形测绘。以冠浪项目为例，提出了地形测量三维模型的生成过程。设计了无人机的飞行路线，无人机斜摄影测量的航向重叠和侧面重叠，并在实验现场进行了图像控制点的布置。CTI T3高精度智能RTK用于图像控制点测量。