When COVID-19 hit Australia hard in early March 2020, like the rest of the world, it changed everything from the way we live, work, and play, affecting almost every aspect of our daily lives. I’m a lecturer at The University of Queensland in Brisbane, Australia, and with the new semester having literally just started a couple of weeks before the coronavirus reached us, everything turned upside down.
Based in the School of Earth and Environmental Sciences, I am lucky to not have to teach my own classes until Semester 2 later in the year, although COVID-19 meant all ‘hands on deck’ in supporting other lecturers adapt to the new ‘normal’. All courses across the university were immediately put on hold for a week, giving staff the opportunity to begin to develop digital resources and devise strategies for online-only teaching.
My own research and teaching interests are in the Earth Sciences, a diverse field encompassing aspects of geology, paleontology, climate systems and more. Over the past five years, I’ve worked closely with colleagues in the school, especially Dr Kevin Welsh, in developing digital resources to support our in-class learning activities. Because Earth Science is founded in the physical world, we commonly teach with real specimens of fossils and rocks, but supplement the learning activities with a range of digital objects that we couldn’t normally bring into the classroom. These include 3D photogrammetric models of hand specimens that are rare or too fragile to safely handle, and even remote field locations such as geological outcrops that are not practical or possible for us to take our students to.
Scanning geological specimens
In many ways, with the shift to 100% online teaching, we were already ahead of the curve, but lacking many of the resources that we needed to round-out the semester. I’ve personally dabbled a little in photogrammetry over the years as guided by 3D guru Nathan Siddle. In fact, we hired Nathan to make 3D models for us when he was a student at the university. Although we trained him in the basics of photogrammetry, he soon became a 3D wizard and taught us more than we could have ever imagined. We’ve used Nathan’s models extensively in the past, but this semester we needed to make even more resources.
Nathan has since taken a position outside of academia meaning that it was left to us to produce the new 3D models. We adopted the protocols that Nathan devised for turntable photogrammetry in our laboratory, although our skills in doing photogrammetry range from absolute beginner to amateur.
I helped train others in my school in photogrammetry with the limited knowledge I have. As models were completed, we slowly fed them onto our school’s Sketchfab page, in some cases, just moments before they were used for online learning activities. The models are not always perfect, but they are useful for teaching.
As per Nathan’s protocol, we use standard digital SLR cameras for photography of hand samples. The samples are mounted on turntables. We generally take anywhere from 100 to 300 photos of a given sample depending on its complexity. We use Agisoft Metashape to process the images and make the 3D models. Sometimes Blender is used to arrange specimens into class sets, before uploading to Sketchfab.
The most challenging samples we deal with are thin, slabbed and polished rocks, and skulls with shiny teeth. Reflections from external light sources can cause some problems when it comes to photo alignment in Metashape. We tend to get around this by taking photos from numerous angles, often temporarily blocking out unfortunately positioned (and fixed) ceiling lights.
Improving and utilizing educational 3D models
One of the things I’m very conscious about is making the 3D models accessible to not only our students, but other teachers across the world and anyone else interested in Earth science. This means, in many cases, adding simple scale bars to 3D models prior to upload; this is critical to give the user a sense of size of the object.
I also encourage our 3D team to add useful descriptions of the models. There are a huge number of great 3D models of rocks and fossils already on Sketchfab, but many are of limited utility for teaching if all they have are descriptions like ‘Sample 7’ or ‘rock’. Sometimes as a teacher, you don’t want to give too much away if the student is required to make their own interpretation, so there is a fine line between a useful description for other users and what you want your class to know.
For integration of 3D models into our lessons, we sometimes direct students straight to the Sketchfab page or just embed the Sketchfab model into a WordPress teaching website that we developed a few years ago (see here for an example). The lessons are usually taught live via Zoom with the students filling in answer sheets that they download from the main teaching and learning platform, Blackboard.
All-in-all, Sketchfab has been a godsend for us. It’s a very easy platform to use from upload to display, and the ability to embed models into other websites to produce curated collections for teaching is outstanding. We’ve just finished Semester 1, with Semester 2 due to start in early August. No doubt we’ll be uploading many more 3D models to Sketchfab by the time the year is out.