Abstract: This paper introduces the UAV tilt photogrammetry technology and its key technologies. Firstly, the high repetition rate oblique image of an overpass is collected through the designed UAV route. Secondly, the processing flow of the collected image data is described in detail, and the technical process of using the collected image data for the 3D modeling of the overpass is also described in detail. Finally, the 3D measurable model of the overpass scene is established. By comparing the accuracy of the selected real site coordinates with the corresponding point coordinates on the bridge model, the results show that the accuracy of the real 3D scene model is reliable, which is made by the inclined image collected by UAV, and the plane and elevation accuracy meet the requirements of the specification, which can be applied to the practical engineering of overpass and other buildings.

Key words: tilt photogrammetry, overpass, image processing, 3D modeling, accuracy analysis