Robot helps capture hard-to-photograph images

By Steve Scarpa

Yale Peabody Museum scientists have created an accessible robotic solution for a problem that affects museums – efficiently acquiring detailed digital images of hard-to-photograph collections and specimens.  

Genevieve Rios, the Peabody’s Head of Biodiversity Informatics Research, and Yale alumnus Jeremy Pustilnik, recently published a paper in the journal Methods in Ecology and Evolution that describe COPIS (the Computer Operated Photogrammetric Imaging System), a robot designed in part at the Peabody to capture imagery of specimens that can be used in making 3D models of them with photogrammetry.  

“Photogrammetry is where you take multiple two-dimensional photos of an object and then you combine or analyze those images to extract 3D information,” Rios said. Examples of COPIS's work can be found here. 

The robot uses multiple consumer grade cameras that can move around specimens. The camera cradles are controlled by an embedded microcontroller operating along five axes of motion. To ensure consistent lighting, LED panels are mounted outside the imaging chamber. Specimens can be placed on the floor of the chamber or mounted on or suspended from supports, depending on the need. 

The system can accommodate a variety of specimen shapes and sizes, and captures images from multiple views simultaneously. Perhaps most importantly, the robot can be run by users with limited technical expertise and constructed for minimal expense. 

Other technologies exist for three-dimensional digitization such as CT scanning, but they can be cost prohibitive, ranging from approximately $300,000 to $5 million, according to the paper. Depending on materials, a full two-chamber, six camera COPIS system may cost only between about $2,000 and $20,000. The initial build requires some engineering knowledge,” Rios said, but once past the initial steps, the technology is relatively easy to use. 

“Gen is making something that other museums could use efficiently and relatively cheaply, and also customize or build on if they wanted,” said Susan Butts, Director of Collections and Research at the Peabody.  

Rios said the project goes back to her days at Tulane in the 2010s. She tried to photograph fish, a particular challenge because the specimens curl in fluid storage, obscuring key physical characteristics. She needed a way to center the object and move the cameras, rather than the other way around. The tool evolved as technology and equipment changed.  

“There is a flourishing community of people from whom I have borrowed their knowledge and lean upon to build this. And people can lean on this to build newer products. It provides a framework that somebody else could improve upon,” Rios said.  

Rios and Pustilnik have already shown how well COPIS works through images of insects where every hair on their legs is visible, detailed views of delicate anthropological objects, and views of some of Othniel Marsh’s original dinosaur specimens, among many others. The 3D object renderings created in COPIS have already been used to create models, allowing for study without the potential for damage to the specimens.  

Researchers at the Museum of Comparative Zoology at Harvard and at CSIRO in Australia have already built their own COPIS units and have expressed confidence in the system. Rios hopes more will follow. With over one billion natural historyspecimens in museums worldwide, the need for inexpensive digitization is obvious. “We want this to be out in the world for people and institutions to use this tool,” Rios said.  

Pustilnik started his PhD at the University of Cambridge in England after graduating from Yale. He recently got a behind-the-scenes look at the collections of the Cambridge Museum of Zoology, including the opportunity to view some of Charles Darwin’s original Galapagos finches with which he used to formulate his famous theory of evolution by natural selection.  

“COPIS has already been implemented at institutions internationally, and I can easily see it becoming a useful tool at even more places such as the Museum of Zoology,” he said, “Then many more people can view and study important specimens like Darwin’s finches without having to be here in person.” 

As more museums and natural history collections digitize their specimens and improve their accessibility, the possibility for new scientific and historical insights can be accelerated. The authors hope that COPIS will be a catalyst for global collaboration, they said. 

You can check out some of the Yale Peabody Museum’s specimens in 3D at https://sketchfab.com/yalepeabodymuseum/models