INTEGRATED 3D SURVEY FOR THE DOCUMENTATION AND VISUALIZATION OF A ROCK-CUT UNDERGROUND BUILT HERITAGE

Abstract. The research presented here is part of an on-going research focused on the 3D documentation of rock-cut Underground Built Heritage with a complex morphology and characterised by narrow spaces, the Hypogeum of Calaforno (province of Ragusa, Sicily). It is one of the most interesting prehistoric monuments in Sicily in terms of size and unique rock-cut architecture. Various digital techniques have been tested over the years on the site, to represent its spatiality, such as Laser Scanner and Structure from Motion. The proposed methodological approach for the knowledge and the documentation of this archaeological site is based on an interdisciplinary approach involving archaeological and engineering disciplines. This paper focuses on the use of expeditious techniques such as iMMS (indoor Mobile Mapping Systems) based on SLAM (Simultaneous Localization and Mapping) and on the comparison of different surveying equipment in order to verify data quality and accuracy, as well as the inherent advantages of using one technology over another in relation to the characteristics of the site. Through the global verification of TLS and SLAM model reliability, we maintain that such research can contribute to enriching the protocols surrounding the archaeological investigation of sites characterized by complex morphology, irregular surfaces, narrow spaces, specific chromatic features, scarce or total lack of lighting, and physical obstacles.