Abstract
In recent years, drones are expanding their use as highly efficient smart support equipment in all industries, including military as well as urban engineering planning and design, construction, In particular, the advancement of drones and GNSS(global navigational satellite system) positioning services, the high efficiency of visible color image RGB sensors, and various selective convergence between thermal infrared sensors and lidar scanning visibility sensors are becoming a key source of spatial information acquisition in the field of construction information modeling(BIM) and 3D digital twin modeling. This study seeks to improve the efficiency of field and office works in drone aerial photography in 3D modeling of urban facilities. For these, after acquiring the 3D location of the drone aerial photography point in two positioning modes, standard GNSS surveying and GNSS RTK precise positioning, the 3D productions were reproduced through the SfM(structure from motion) image analysis process, and the accuracy and efficiency of the work process were compared and considered. As a result of the study, when GNSS RTK precision positioning (VRS ; virtual reference service) is applied during outdoor filming, it was possible to reproduce and demonstrate the effectiveness of the digital twin modeling within the allowable range by omitting the GNSS surveying for additional ground control points and geo-tagging for the real-world model conversion of 3D image analysis results in image processing.