High resolution 3D recordng and modelling on the Bronze Age cave "les Fraux" in Perigord (France)
Résumé
The Bronze Age cave “Les Fraux” at Saint-Martin-de-Fressengeas (Dordogne, France) has been discovered in 1989. This site made of a network of galleries of several hundred meters, is a field of investigation for several researchers. This paper will focus on three dimensional contact free measurement techniques for a full 3D-documentation of the structural elements of the cave with some focus on cave art details. In this cave, most of the art is etched in the clay and follows linear, schematic and geometric designs. There are indeed several manmade depictions on the walls and other valuable remains of activity all around the cave. For the archaeologists, the documentation and recording started in 2008 should:
- contribute to the accurate indexing of the surveys and images of the remains and collections as well as structural elements and
sculptures;
- guarantee the indexing compatibility of the data between the different groups of researchers involved in the excavation;
- ensure the georeferencing of any type of object in the different parts of the cave.
Different techniques based on Terrestrial Laser Scanning (FARO Photon 80), Digital Photogrammetry (CANON EOS 5D images)
and Spatial Imaging System (Trimble VX) have been used. The aim of the documentation work is to generate a geometric and
photorealistic 3D model from the combination of point clouds and photogrammetric images, for both visualization and accurate
documentation purposes. The underground tunnels of the cave are linked to the above terrain with surveying techniques for an
accurate georeferencing. The workflow from the raw data to the final PDF-3D model will be discussed. Emphasis will also be given
to the deliverables, since the huge amount of data is not directly usable by the archaeologists.
Origine : Fichiers éditeurs autorisés sur une archive ouverte