Associating Geodetic Theory to Digital Pottery Reassembly Practice

Abstract

Geodesy is a scientific branch of the science of Geography dealing with accuracy and precision in measuring and understanding Earth’s geometry, including its orientation in space. It is mainly based on geometric quantities, such as angles, distances, distance differences, directions, curved lines, elevations, elevation differences, and it primarily solves geometric problems, determining the shape and size of our planet and calculating, coordinates on its surface. Similarly to the study of Earth’s spatial elements, theories of geodesy can also be transferred to investigate smaller-scale spherical/ellipsoidal objects. To this end, since the shape of ancient ceramic pottery is an ellipsoid formed by the rotation of a potter’s wheel, in this paper it is presumed that on a ceramic pottery a similar to Earth’s geodetic network may be hypothesized, researched and used. Therefore, in line with all the above, we describe a methodology based on precise geodetic distances that can be extracted from arcs of ellipses deriving from the traces left by the potter’s fingers on the internal side of sherds. This can be achieved through high precision digital 3D models that we have previously obtained using photogrammetry and macrophotography (close-range photography). By extracting geometric quantities from each digitally modeled sherd, it is possible to gather local geodetic set of distances, which we will then compare with respective sets of candidate conjoined sherds for successfully arranging them their original position.