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with such an opportunity looming, scien- tists and imaging specialists volunteered their time and loaned their expertise, while companies, such as Ford Motor Co., NDT Group, and Carestream Health, donated knowledge and expensive materials—all in the name of science. Some funding resulted when a fi lm crew, led by Michael Jorgensen, documented a good portion of the project for the MidCanada Entertainment/Myth Merchant Films movie titled Secrets of the Dinosaur Mummy. Further work was ad- vanced through the Judith River Dinosaur Foundation in Malta, which co-owns the fossil with the Hammond family, on whose land the specimen was found. Art Andersen, president of Virtual Sur- faces, was among those within the imaging community who became involved in the project. "I have done 3D scanning and ed- iting for years, and I thought this would fi t nicely into our work," he says. Andersen, whose experience spans industry as well as paleontology, was a catalyst for bringing many of the other scientists aboard. e project was multifaceted. For a thor- ough look at the outside of Leonardo, the group would perform a digital scan, edit the resulting data into a single fi le, and lat- er output a physical rapid-prototype (RP) model of the dinosaur. For an internal exam, the team X-rayed the specimen fi rst on site at Malta and then at NASA John- son Space Center's Ellington Field facility in Houston, later enhancing the data for a clearer picture. e crew also performed an elemental scan on a section of Leonardo, which analyzed the natural elements that were present in the body and off ered clues as to the colors of his skin, for instance (see "It's Elemental," pg. 39). Scratching the Surface On the outside, Leonardo is well pre- served, albeit extremely fragile. So when it came time to make a mold and cast of the dinosaur, the usual process of covering the surface in latex or silicon rubber was out of the question, as it was sure to permanently damage the once-in-a-millennia discovery. Furthermore, the chemicals from the pro- cess likely would have contaminated the fossilized skin, making it impossible to do certain types of testing. "He has a lot of cracks and loose parts on him, and traditional modeling or cast- ing could have destroyed him," says Ander- sen of the fossil. Moreover, Leonardo's frail state prohibited him from being transport- ed to various labs for further examination. Alternatively, the group decided to employ white-light scanning to capture and then generate an anatomically correct 3D computer-generated image of Leonardo's entire exterior; later, the resulting data would be used to create an exact three- dimensional physical replica of the creature. Other research- ers could examine Leonardo through a hands-on approach using the resulting casts. Andersen contacted an industry col- league, Joe Lichko, president of Cubic Vi- sion, and soon they, along with the other scientists, were huddled over Leonardo in Malta, each with an important task at hand. Lichko, who has worked with Andersen in both manufacturing and paleontology, had brought along his proprietary 3D scanning system that he developed over the years. "Leonardo is like a big [piece of ] sand- stone that is barely held together," de- scribes Lichko. "If you touch him, little pieces would literally fall off , and eventu- ally you would destroy him." e white-light scanner projects a grid pattern onto the fossil, while a pair of digi- tal cameras on either side of the light-source box map the smallest detail of the surface. What's so unique about Lichko's scanner is that he is able to change the intensity of the light. " ere are some very light and some very dark patches on Leonardo, so we were able to stay in the same spot and do multiple scans with diff erent light in- tensities, and pick up all the features of the dinosaur," Lichko says. e line-of-sight scanner captures a very fl at fi eld over the entire area, meaning that from edge to edge, corner to corner, there is no warping, as there is with many other scan- ners. is was key, since Lichko did more than 300 scans to get every nook, cranny, and undercut. Each scan comprised an aver- age of 1.4 million points, which was neces- sary for capturing the fi ne details of the large specimen: Even though Leonardo was an adolescent, he was still quite large by modern standards. His fossil measures approximately A white-light scanner (above) was used to generate an accurate 3D surface model of the dinosuar. (Inset) A close-up look at the beast's head and neck. © Black Hills Institute of Geological Research. July 2009 32 ■ ■ ■ ■ Digital Imaging

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