3D scanning and printing in paleontology. Continuation

Published on November 08, 2015

3D scanning and printing in paleontology. Continuation

    In a previous article, I briefly talked about the possibilities of 3D printing in paleontology, namely the creation of three-dimensional reconstructions and models of fossil animals from the Cambrian shales of Burgess.

    Unfortunately, at that point in time, we did not have a video about the work process, so I want to show it in this note:

    In addition to reconstructions of the Cambrian shale fauna of Burgess, created manually by the modeler, we also printed an exact copy (three-dimensional scan) of the holotype * of the skull of an ancient Miocene ** primate - proconsul ***.
    * holotype - an instance of a biological object that was used as the main one for describing a particular species (or other taxon).
    ** Miocene - the era of the Neogene period, began 23 million years ago and ended 5.3 million years ago.
    *** proconsul (Proconsul) - genus of fossil primates of the Miocene epoch, existed 17-21 million years ago in Africa (Figure 1, a.).

    The skull of the proconsul (Proconsul heseloni) (Fig. 1, b) was found on Lake Victoria and is stored in the National Museum of Nairibi (Kenya). A few years ago, it was scanned (Fig. 1, c) by the African team of paleontologists aficanfossils.org and is publicly available in * stl format.
    After printing, when the sample could already be held in hands, we were struck by the detailing of this exhibit (Fig. 1, d). Roughly speaking, the fact that our printer "was born" is not just a copy, but the most accurate replica , according to which a sample can be studied by paleoanthropologists.
    Fig. 1. Proconsul heseloni. a - reconstruction of the appearance of the primate; b - a photograph of a holotype skull at the National Museum of Nairobi; c - 3D model obtained by scanning by African colleagues; d - a printed model at the Darwin Museum

    All five samples became part of the experimental display case (see video above), which is located in the Darwin Museum. It was a test of the pen, which gave rise to a new large-scale project: we had the idea to create a collection of scans of real samples and their subsequent printing. It seemed to us the most interesting to collect a complete (about 50 species) collection of skulls of hominids from the Miocene to the present and present it in the form of a phylogenetic tree in a display case. In stock, we had a limited number of models with which to start a new project. So, after the proconsul, the lower jaw of Paranthropus boisei * (Fig. 2, a-b) and part of the jaw of Homo naledi * were printed.

    * Paranthropus boisei (Parantrop Boise) - the most massive species of parantrops, discovered in 1959 by Mary Leakey in the East African gorges of Olduvai, Koobi-Fora, Lokalei and several others. They are dated from 2.5 to 1 million years ago.
    ** Homo naledi is a fossil species of people of the genus Homo. The remains of H. naledi were first found in 2013 in the Republic of South Africa. Very fresh look).

    Fig. 2. a - reconstruction of the appearance of Parantrop Boyce; b - a comparison of the upper jaw of Parantrop Boyce on the right and the upper jaw of a modern person; c - the lower jaw of Parantrop Boyce printed on a 3D printer at the Darwin Museum.

    Since, as mentioned above, we had a limited number of ready-made scans of hominid skulls, it was decided to continue the project in line with the scan. We turned to various institutions (both Russian and foreign) that have the samples we need.
    So, for example, our dear friends, the portal anthropogenesis.ru kindly agreed to participate in the project and provided material.
    The skull of the Heidelberg man (Homo heidelbergensis), provided by the assistant professor of the Department of Anthropology of the Biological Faculty of Moscow State University S.V.Drobishevsky, was selected as the first test copy for scanning. (Fig. 3, a).
    It is important to note that there are at least two available ways to create three-dimensional digital copies of objects - direct scanning and photogrammetry. The first assumes, as it is obvious, the presence of a scanner, the second - only a camera and specialized software.
    The Darwin Museum, fortunately, has all the available technology. We have an EVA * scanner that looks more like an iron than expensive equipment *, with which we went to scan the skull we are interested in.
    Fig. 3. a, b - skull of Homo heidelbergensis; c - Researcher of the Darwin Museum Savin R.Yu. scans the skull, behind - Assoc. Drobyshevsky S.V .; d - your humble servant is grimacing with a skull and an EVA scanner.

    Since we are scientists (more precisely, scientists with the bitter experience of mistakes), we did photogrammetry in addition to conventional scanning. By the way, if you pay attention (Fig. 3), you will notice that the skull lies on the newspapers (Trinity version by the way). This is not so simple - letters and words on newspapers are markers for scanning and photogrammetry. Let’s put it this way: we did not have high hopes for simple photographing, but did it for safety.
    Actually, how can creating a 3D model with a professional scanner be worse than creating a model using photogrammetry ?! Nonsense and nonsense ...
    But the result (Fig. 4), frankly, shocked us a little: the skull model created by a simple camera and special software turned out to be several times more accurate!
    Fig. 4. The result of scanning the skull of Homo heidelbergensis. а - model obtained by the EVA scanner (Artec Studio program); b - model obtained by photogrammetry (Agisoft PhotoScan program).

    Therefore, it was decided to continue scanning using photogrammetry rather than an expensive scanner, which is not paradoxical ...
    At the moment, we are faced with the problem of smooth and proper rotation of the camera around the sample and are busy creating a special rotating table with lighting.
    On the future of the project, if you were interested, I will tell you in the following notes.