BIONIC BONES: USING LASER TEXTURE SCANNING AND 3D PRINTING TO RECONSTRUCT DAMAGED VERTEBRATE FOSSILS

In 2007 a partial Edmontosaurus skeleton was collected from the Hell Creek Formation (latest Maastrichtian) of southeastern Montana (BMRP 2007.4.1). The skeleton consists of two anterior caudal vertebrae, and extensively weathering and pyritized pelvic elements. Damaged and poorly-preserved vertebrate fossils have usually incorporated artistic reconstructions based on measurements of better-preserved specimens to fully restore missing remains. However, the accessibility of digital reconstruction techniques such as laser texture scanning and 3D printing can yield low-cost and accurate reconstructions. To illustrate this technique, ilia of both the damaged specimen and a complete, well-preserved specimen attributable to Edmontosaurus (UWGM 2091) were digitized in high definition with a NextEngine Desktop Laser Texture Scanner mounted to a 3-meter tripod. The digital scans were reconstructed, extruded, and solidified to produce a dense point cloud and mesh in AutoDesk Meshmixer. Once both ilia had been digitally assembled, the portions represented by the complete specimen were inserted to produce a full reconstruction of the damaged specimen. Furthermore, portions of the reconstruction representing the original damaged ilium were also extruded and inverted to serve as a custom-fit cradle that is connected to the reconstructed portions, allowing for the safe removal of the original specimen from the reconstruction for future study. In order to produce a tangible reconstruction, the final mesh was uploaded to an XYZ DaVinci 1.0 3D printer and printed using Octave 1.75mm acrylonitrile butadiene styrene (ABS) plastic filament extruded at a 0.2mm layer thickness. The resulting structure provides a custom-fit cradle for the damaged Edmontosaurus ilium as well as an accurate reconstruction of the missing portions of the ilium. While the initial startup costs for this technology are considerable, the low-cost of ABS filament and the relatively short processing and construction time to produce an accurate reconstruction makes this an extremely efficient technique for vertebrate fossil restoration.