Pottery Plotted by Laser – 3D Acquisition for Documentation and Analysis of Symmetry of Ancient Ceramics

Abstract

Due to increasing demand of archaeologists for accurate and fast documentation of ceramics, we provide an automated system for acquisition and documentation of sherds. This is done by 3D-acquistion using structured light and by estimation of the profile line using the axis of rotation. As ceramics manufactured in South America are not supposed to be manufactured on rotational plates, we conducted experiments together with the German Archaeological Institute (DAI) to apply and adapt our system on freehand manufactured Nasca ceramics. The experiments including a comparison between manual and automated drawings of profile lines were done in-situ at the excavations in Palpa, Peru. To gather a ground truth about the vessels the sherds belong to, we acquired 102 complete vessels with well-known archaeological context. The symmetry of these vessels was analyzed and experiments for automated profile estimation were used to cross-validate existing classification rules. We could show how to assist archaeological work by estimation of profile lines and additional quality features based on the symmetry of the acquired vessels. Furthermore we show how the use of 3D-scanners can be used by estimation of unwrapped surfaces and virtual restoration of decorations of the painted Nasca fine-ware (30–40% of the findings). Therefore we can show that the documentation can be done in a fraction of time compared to manual documentation. We also show how the high resolution 3D-acquisiton can be used to answer archaeological questions about ancient manufacturing techniques of ceramics.