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Research on fine 3D modeling technology of tall buildings based on UAV Photogrammetry

Based on the principle of oblique photogrammetry, it used DJI phantom 4 PRO, one kind of light UAV photogrammetry system, to collect the oblique photogrammetry image data of tall buildings, and then produced real scene 3D model by the oblique photogrammetry modeling software. While the real scene 3D model results show much distortion and deformation. In order to improve 3D model results, it designed four side elevation flight and data processing schemes based on the photogrammetry principle. In addition to the above oblique photogrammetry images, four side elevations images of the tall building are collected separately by DJI phantom 4 Pro with certain overlaps. Meanwhile it surveyed some image control points and test points to grantee the results precision and texture authenticity. During the data processing, the four side elevation images and the oblique photogrammetry images are combined to perform the Aerial triangulation (AT) calculation. Then it produced a new scene 3D model. The results showed that the new model has significantly been improved both in accuracy and texture authenticity. This method satisfies the need of fine realistic 3D modeling of tall buildings and provides strong support for fine 3D modeling of smart cities.