Through the years, Direct Dimensions has had the opportunity to help researchers study and uncover many of history’s mysteries. Among many great projects, we’ve scanned ancient Egyptian statuary, man’s earliest writings, and even walked in George Washington’s footsteps. Last year brought us with two interesting projects with ties to an even earlier period in time: the prehistoric Mesozoic era!
There is so much we still don’t know about the fascinating time when dinosaurs roamed the Earth, and we had the exciting opportunity to use our cutting-edge 3D technologies to study the fossilized bones of two species of dinosaurs—a hadrosaur and a pterosaur.
In early 2008, a research group from Johns Hopkins University, led by renowned paleontologist Dr. David Weishampel, visited Direct Dimensions with a challenging and unique 3D problem. Dr. Weishampel heads the Center for Functional Anatomy and Evolution within The Johns Hopkins University School of Medicine in Baltimore, MD. He has written numerous books and scholarly articles on the subject of dinosaur anatomy including The Dinosauria, which is widely regarded as one of the most complete, authoritative books on dinosaur scholarship ever published. In fact Stephen Spielberg even asked him to consult on the movie Jurassic Park, for which Dr. Weishampel received an Academy Scientific and Technical Award.
Dr. Weishampel and his student team led by Masters candidate David Chaney, brought pieces of a skull from a hadrosaur dinosaur that Weishampel had discovered. Hadrosaurs were duck-billed, ornithischian dinosaurs that lived during the Upper Cretaceous period during the Mesozoic era. He believes that this particular specimen belonged to a newly-discovered species that heretofore not been studied. The particular skull was in several pieces, and due to the fragile nature of the skull, the pieces had not yet been physically joined together. In short, no researcher had physically ever seen the complete assembled skull of this species of hadrosaur. In order to aide with his research, Dr. Weishampel asked Direct Dimensions to help him assemble the complete skull – virtually – using our 3D laser scanning and digital modeling capabilities.
In order to accomplish this task, the 20-plus plaster-cast pieces of the hadrosaur skeleton were brought to our facility in Owings Mills, where technicians Jeff Mechlinski and Jon Wood scanned all the fragments with our Kreon Zephyr laser scanner mounted on a Faro Arm. With its especially highly accurate laser, and the fact that no physical contact with the item is necessary, the Zephyr scanner is particularly valuable for obtaining fine detail on delicate items like the bone castings.
The raw data from the laser scanning was then processed in PolyWorks software to create 3D digital models of each of the individual pieces. This process involves importing the millions of x,y,z 3D points into the software, combining the multiple scan passes together, and then stitching the ‘cloud of points’ into the watertight meshes for each individual fragment. While PolyWorks does most of the heavy lifting, its still takes skill and at some level an artistic touch to finalize each of the parts into the final formats. This is a particularly strong skill within Direct Dimensions since we’ve modeled thousands of objects.
The next step was to digitally align and assemble the parts together into an accurate model of the complete hadrosaur skull. With visual and verbal instruction from Dr. Weishampel, Mechlinski brought each piece together and manipulated them by adjusting both position and orientation.
“It was a digital jig-saw puzzle in 3D,” noted Mechlinski, “ as I added each new piece, I needed to adjust each of the neighboring pieces so that overall it fit together as a single assembly. Since the skull had been fragmented, it was not even clear if we had all the pieces.” In the end, using the color-based fit analysis capabilities within PolyWorks, Mechlinski and Weishampel verified that each piece connected properly and that the overall skull formed a tight assembly.
To further demonstrate the power of the 3D digital environment for such a unique and exciting project, the Direct Dimensions team created an interactive visualization showing how all of the pieces come together to form the complete skull. Using the animation software 3D Studio Max, engineer Dominic Albanese and graphics designer Mark Ludwig created a web-basd Direct3DView animation complete with the parts coming together and then falling apart. In each state, the user can rotate, pan, and zoom the scene to better see what the parts look like either apart or assembled.
Working with Dr. Weishampel and the Johns Hopkins students on the hadrosaur project was so amazing that we gladly agreed to do it again – this time with the ancient bones of a pterosaur. Pterosaurs, known more commonly as pterodactyls, lived in the late Triassic to the end of the Cretaceous period— which meant our two peculiar reptiles likely lived for some of the same time. Pterosaurs are particularly notable because they are the first known vertebrate creatures to have evolved winged flight and could grow quite large—the largest known pterosaur had a wingspan of about 33 feet! However, because their bones were hollow bones, the skeletons preserved very poorly, as they are often crushed by the weight of sediment. So when you find a good skeleton, there is much to study about these great creatures.
This is what Julia Molnar, a graduate student at Johns Hopkins University department of Art as Applied to Medicine, brought to Direct Dimensions – a set of bone castings from a well preserved pterosaur skeleton. For her masters thesis project, Ms. Molnar was studying the way in which pterosaurs would have taken flight. Very little is known about their launch sequence, and how such an enormous creature could vault into the sky without dragging its giant wings along the ground.
Thus the challenges – digitize the cast pieces, assemble correctly into a complete skeleton, and help formulate the 3D motion sequence for the ancient creature within the computer.
Step 1: Direct Dimensions scanned the castings of the 8-foot pterosaur skeleton with a FARO Arm equipped with the FARO laser line scanner. Like the Zephyr used on the hadrosaur castings, the FARO laser scanner also collects precise data without ever having to physically contact its target. The fragments were each scanned in two positions—one with the limbs folded inward, as they would have been when the pterosaur was grounded or at rest, and the other with the wings fully extended, as they would have been in flight.
Though there were some difficulties during the scanning process, they did not prove insurmountable. Ms. Molnar described the process: “The scanning was challenging because there were many undercuts, particularly around the ribcage, and the casting is very fragile. I was really impressed with the way they handled the challenges.”
With Molnar helping explain how the components go together, technician Jon Wood created two 3D digital models of the entire pterosaur skeleton - one for each of the two positions: on ground and in flight.
With these completed digital 3D models, Ms. Molnar then created a 3D animation to show the launch movement. Working in a software program called 3D Studio Max, she applied the constraints that paleontologists had previously discovered about pterosaur flight to animate the transition between the closed, resting position and the open flight position. She discovered that pterosaurs very likely had a quadrupedal launch—a two-phase motion that pressed upwards with the hind legs and then followed that with a forward vault motion using its forelimbs. This technique enabled the pterosaur to clear the surface without dragging its wing tips along the ground.
So in just the span of just one year, Direct Dimensions used our 3D laser scanning and digital modeling skills to advance the research of two of prehistoric creatures. We hope to have more projects like this in the future. There are no limits to how we can use our innovative 3D technologies to uncover our world’s most buried secrets.
