A method of urban high-precision DEM construction based on point cloud model

A high-precision DEM represents an indispensable foundation for urban planning, construction, and management. It provides support and rationale for sustainable urban development, environmental stewardship, and disaster management. However, existing studies have primarily concentrated on open areas within the field or specific areas, such as urban roads and flood-prone regions, with comparatively limited attention directed towards urban areas characterized by intricate topography and overlapping features. This paper presents a case study of Chuzhou University in Anhui Province and proposes a construction method applicable to urban high-precision DEM by leveraging the distinctive attributes of point cloud models, including high precision, high resolution, and rich texture information. Firstly, the point cloud characteristics of ground objects are employed to elucidate the boundary between ground and non-ground points, thereby facilitating the precise separation of ground and non-ground point clouds. Subsequently, the slope factor is introduced to achieve an adaptive adjustment of the threshold for the height difference of the point cloud surface fitting. Finally, the urban high-precision DEM is constructed through a partitioning process that accounts for the diversity of urban surface morphology. The experimental results demonstrate that the proposed method in this paper exhibits superior performance in terms of point cloud filtering accuracy, DEM construction error, efficiency, and method adaptability when compared to traditional elevation grid, ordinary Kriging model, and other methods.