Mapping caves due to photogrammetric data

The authors present a new approach to mapping hard-to-reach caves. It relies on a modern framework of ground-based stereo photogrammetric and geodetic surveying, aerial photography from UAVs and computer modelling. A stereo system was designed and assembled, consisting of two GoProHero9 Black cameras and a powerful artificial light source with diffusing lens, mounted on the operator`s helmet. The site for underground filming was the Syanovskaya quarry (Moscow oblast, Domodedovo rayon). The aerial survey of the cave ground part was also made with DJIAir 2S UAV; it included a ravine with a concrete well, which was the entrance to the quarry. The article deals with the processes of geodetic georeferencing, external orientation of the surface model and underground parts of the cave, as well as the cartographic materials obtained in the course of the work