Photogrammetric 3D modeling of underground excavations using smartphones: A cost-effective alternative to LiDAR

A novel methodology for constructing three-dimensional models of underground mine workings has been developed utilizing mobile devices and spherical photogrammetric coverage technology. Experimental implementation in a hydraulic tunnel section enabled evaluation of model accuracy and stability across different photographic approaches. Comparative analysis of two 3D models generated through linear versus spherical imaging schemes revealed significant advantages of the spherical method in terms of point cloud density, visualization quality, and alignment stability. The study further examined the effects of lighting conditions, shooting distance, and video footage utilization on model quality. Results demonstrate that mobile photogrammetry serves as an effective alternative to costly laser scanning technologies for underground mine surveying applications.