Study on Earthenware Fragment Assembly System Based on Estimating Spatial Arrangement of Earthenware Fragments

Restoration of earthenware fragments is an important task in archaeology.Earthenware fragments excavated from archaeological sites are restored by hand, but there is a risk of defacement or damage to the fragments.Computer-aided restoration methods have been proposed.For example, there is a system in which fragments are arranged on a twodimensional panel and assembled by the user as if they were a puzzle.For efficient assembly, it is important to clarify the vertical direction of each fragment.For this purpose, a method has been proposed to estimate the vertical direction from a point cloud, assuming that a fragment is placed on a desk.However, this method may result in estimating an inverted posture.Therefore, this paper proposes a method for accurately estimating the vertical direction of a fragment by linear regression using a three-dimensional point cloud.In addition, the fragments were initially placed in a two-dimensional panel based on the vertical direction of the fragment and the radius of the circle approximated from each cross-section of the fragment.Subsequently, the system was developed to virtually assemble the fragments in three-dimensional space by interactively manipulating the fragments on the two-dimensional panel.