Learning Library for Three-Dimensional Animal Models

What do you do with nearly 600 sensitive animal preparations? At the Faculty of Veterinary Medicine of the Ludwig-Maximilians-University Munich (LMU)researchers had already purchased a hand scanner (Artec Space Spider) to convert bones, teeth and organs into digital objects of interest. In the long term, this should have resulted in a database that students can use to learn. Then came the corona lockdown and the digital semester: And all of a sudden everything had to happen very quickly. "The Leibniz Supercomputing Centre (LRZ) has been a great help to us and has shown us ways to make the scans available to students quickly," says lecturer Sven Reese. The veterinary surgeon with a doctorate in veterinary medicine sought advice from the Centre for Virtual Reality and Visualisation (V2C) at the LRZ: "Presenting 3D data via the Internet is not so easy. In the meantime, almost 300 of the specimens have been scanned, about 40 of which can be accessed via the faculty's Moodle learning platform or atSketchfab for study purposes. With the university library, the veterinarians are now planning a platform for three-dimensional objects. An interview with 3D specialists Lea Weil and Kristian Weinand from LRZ' V2C on how digitization and innovative visualization are changing research and teaching.

When and how did the cooperation with the veterinary faculty begin?

Lea Weil: Last winter, Sven Reese contacted us and asked how to visualize preparations in 3D. A scanner, which displays colours and textures of skin and bones, had already been purchased, but there was uncertainty about how the virtual preparations could be made available to the students. A smartphone app first appeared to be the got-to solution for rapid provision. Enriched with augmented reality functions the specimens would have appeared even more lifelike. However, many students use smartphones based on different operating systems and versions, which could have led to problems with installation and display. On an online platform, the preparations can be accessed via a 3D viewer using a computer, notebook, tablet or smartphone - in this case the best way.

How do you find such tools?

Kristian Weinand: On the Internet, at museums, universities and other specialists. We looked at tools like Verge 3D, Blend4Web, Sketchfab, and the viewer used by the Smithsonian National Museum of Natural History in Washington and experimented with scans from the Veterinary School. The presentation and interaction with the objects are similar, all of them allow you to rotate and turn the objects. For the evaluation, we therefore looked at the quality of view and user-friendliness as well as the costs of use. Criteria such as the limitation of access rights, data security and data storage also played a role. Because the corona lockdown had to make things go faster, we recommended Sketchfab. The platform is well established, the tool is easy to use, uploading is fast and straightforward. Sketchfab offers a website with an integrated viewer and many functions, such as captions or annotations. Many universities and museums publish their exhibits there. However: Sketchfab stores the data in the USA, with the free version everyone can download everything. The Faculty of Veterinary Medicine has decided to opt for a subscription to limit access.
Weil: In the long term, a separate platform would be more practical, but the development should not be underestimated financially, especially if it is to grow with the requirements and wishes of the students. Then it can also be determined where the data will be stored. Bavarikon, the Internet portal of the Free State of Bavaria, uses its own 3D viewer to make art, cultural and knowledge treasures accessible in 3D.

Scanning and uploading - does it work just like that?

Weinand: Not quite, if you want the visuals to be loaded quickly. 3D scans produce large amounts of data that need to be optimized if users want to access them online and with mobile devices. The scans consist of a fine grid that can be reduced to a coarse resolution to minimize file size and complexity. However, this results in the loss of details that can be projected and preserved using textures. But this requires some more work steps and additional software. In this case we have recommended Blender - a free open source program. It combines many functionalities, which could make the optimization of 3D models more difficult. For an uncomplicated standard work-flow we have therefore created a video tutorial. It worked just fine, and everyone got along well with it

Now the preparations are available at Sketchfab, what else could you do with them?

Weil: Integrated in augmented or virtual reality apps, the individual preparations could be presented in an even more impressive and playful way and enriched with additional information. They convey an immersive impression, as if the three-dimensional model were on the table and one could interact with it naturally. This clarifies the real proportions, shows the similarities and differences of, for example, pelvic bones of different animals. In such apps, preparations can also be assembled virtually, for example the teeth with the jaw bones. The visual objects look lifelike, which is also a great advantage for learning. Combined with animations, complex relationships could be illustrated. A whole lot is conceivable.

Not only veterinarians have spatial visualization objects, in which fields could sketchfab and 3D-viewer support teaching?

Weinand: They are already being used in archaeology and art history. Architecture, mechanical engineering, biology and quite a few more science domains also work with three-dimensional models and benefit from spatial representation. In the long term, an online platform for three-dimensional objects is to be developed at the LMU and the university library. This will open up many opportunities for the exchange of information between universities, students and researchers and interested experts worldwide. Rare and sensitive specimens, which are otherwise well protected in universities or museums, will thus become publicly accessible, worldwide. That is great.
Weil: I am sure that augmented, virtual and mixed reality applications or platforms for 3D views, which we also develop at the Leibniz Supercomputing Centre, will enrich research and teaching enormously. The corona lockdown has pushed the digitization of learning content. Hopefully, the experience gained will be taken into account when the situation recovers. Then it will not be long before soon-to-be physicians will be able to spatially explore organs, bones and tissue of humans or animals with the help of data glasses and an AR app. This will make learning more sustainable, more impressive. (vs)