Abstract: Three-dimensional modeling has been widely used in cultural relics protection, engineering surveys, urban services, emergency disaster relief, forestry protection and other aspects. Based on actual engineering experience, this paper studies the three-dimensional modeling of ancient buildings for close-range photography of multi-rotor drones, and proposes a three-dimensional modeling method for ancient buildings that combines autonomous flight with manual multi-height and multi-angle photography. The experimental scene verifies the accuracy and quality of the 3D model. At the same time, the control points placed on the ground are introduced, aerial triangulation and dense matching technology are used to obtain the three-dimensional coordinates of each feature point on the ancient building, which provides a new idea for the study of close-range photogrammetry in the deformation monitoring of ancient buildings.

Key words: unmanned aeriac vehicle, close-range photography, ancient building, 3D modeling, ground control point