CGSociety :: Technology Focus
4 March 2010 by Meleah Maynard
A week after papers published in the journal Science in early October 2009 sparked global headlines about the discovery of a 4.4-million-year-old partial skeleton in the Ethiopian desert, Discovery Channel aired 'Discovering Ardi,' a two-hour special on the subject. This was the documentary that showed how Ardi may have looked, moved and lived in the woodlands of East Africa.
It helped people understand the shattered remains of a species called Ardipithecus ramidus (nicknamed 'Ardi'). It also changed what we thought we knew about human evolution.
The upThink Lab, a video production and post studio in Atlanta, brought the world's oldest partial hominid skeleton to life using MAXON's CINEMA 4D. They were asked to create graphics and 3D animations for the project in 2008 by Rod and David Paul of Primary Pictures, an HD video production house in Atlanta.
The father and son company had already been collaborating with the Middle Awash research team that found Ardi and Discovery Channel, for almost ten years to develop the documentary.
The creature work was done in Maya and Mudbox. Primary Pictures worked with two artists, Mashru Mishu
and Massimo Righi
for the creature modeling and fur. Mashru did the sculpting and texturing and Massimo did the fur and still frame renders.
Configuring and animating Ardi's partial skeleton was a painstaking process, says Doug Urquhart, who co-founded upThink with Erik Huber in 2007. An international team of scientists had been working on solidifying their analysis of the fossilized remains since they had been found in 1994.
It was still common for them to revise their thinking about how a particular bone may have moved. In order to present a scientifically accurate film, all of the 3D models of the skeleton needed to be flawless and properly aligned. "And we knew there was no way we were going to attempt to create accurate 3D models of our own for the fossil remains," Urquhart recalls. He has been working with CINEMA 4D since 2002.
This animation of Ardi's partial skeleton began with 3D scans of the actual fossils and ends with the reconstructed skeleton in its entirety. The white glow visible in the image on the left is the wipe transition between the partial skeleton and the reconstructed one.
Images courtesy Upthink Lab
To illustrate the process of how 33 fossils fit together to create the cranium, upThink created this animation showing the fragments meeting in 3D space. Images courtesy Upthink Lab
So Urquhart and others on the creative team came up with a plan to use 3D models of the fossils. These were made by Japanese paleoanthropologist Dr. Gen Suwa, a member of the Middle Awash team. The only trouble was, Suwa's models were too large to send because they came from micro-CT scans he had done of each bone in 2003.
A rare and expensive piece of equipment, the scanner had allowed Suwa to gather an outstanding amount of detail. It even captured the 3D geometry for the inner components of the bones.
While this was great for accuracy, the huge files were completely unwieldy to handle. The team solved the problem by having Suwa upload his dense meshes in PLY file format. Working together, Urquhart and David Paul, the supervising producer on the project (his father, Rod, was executive producer), downloaded the files. David figured out how to convert the PLY files to OBJ files using open-source software so they could be imported into CINEMA 4D. But the difficulties didn't end there.
The 3D chimpanzee in the lower right corner was created from a chimpanzee skeleton Primary Pictures scanned bone-by-bone in 3D (using a NextEngine Desktop 3D scanner) and positioned. "We used the scans to build this 3D skeleton in the knuckle-walking position," Doug Urquhart, upThink's creative director, explains.
Urquhart and the small team of freelancer artists worked to assemble bones into parts of the skeleton. Project files often reached 700Mb pushed CINEMA 4D 10.5 to the limit, with the memory usage issues bringing their systems to a near standstill. Then Release 11 came out. "It really saved the day," Urquhart recalls. "Even though Cinema 4D had a way to simplify the meshes, when we did that it reduced the polygons to levels that weren't acceptable to the scientists anymore."
In this shot, viewers get a look at Ardi's partial skeleton (brown) with an X-ray overlay (semiclear white) that helps make clear how Ardi's complete skeleton might have looked.
Images courtesy Upthink Lab
In all, upThink made over 100 animations for "Discovering Ardi," at least half or which were made using CINEMA 4D. Each one helped scientists explain how different parts of Ardi's body looked and worked. In one sequence about her pelvis, for example, upThink used CINEMA 4D to create a 3D pelvis of a human and a chimpanzee.
The goal was to have the animation help viewers draw comparisons, enabling them to see how Ardi ties in to human lineage. "David Paul was so helpful with all of this," says Urquhart. "He was right there giving us direction every step of the way." In fact, knowing how useful Suwa's micro-CT scans had been when they were configuring the Ardi partial skeleton and representation, Primary Pictures purchased a 3D scanner and used it to create scans, one bone at a time, of a chimpanzee skeleton.
Once he had a fully reconstructed skeleton to work with, one of the biggest challenges Urquhart faced was making Ardi's partial skeleton walk.
Photographs taken at the excavation site in Ethiopia were broken up in Photoshop into different layers and animated for the film. On the right is an actual photo of part of the fossil and on the left is a 3D model. "We were instructed to steer away from having matching textures because the scientists wanted people to know when they were looking at a 3D representation," Urquhart explains.
Images courtesy Upthink Lab
To help determine how Ardi may have walked, Dr. Owen Lovejoy, a biomechanics expert and science team member on the project, used the biomechanics firm, LifeModeler. Urquhart brought in well known CINEMA 4D plug-in developer Cactus Dan
who used his CD IK Tools plug-in to handle the character rigging and animation. "Then, it was easy for us to align high-res fossils with the low-res proxies and create an XPresso system (CINEMA 4D's node editor) so we could toggle between them," Urquhart explains. Rendering was done with CINEMA 4D's NET Render using six Macs in upThink's studio. After Effects was used extensively with MAXON's After Effects compositing files for camera and layer positioning.
upThink brought in Cactus Dan to rig and animate Ardi's walking skeleton. "It took a lot of complex rigging to have a walking skeleton with every fossil separated in 3D space and ready to align into position to start walking," says Urquhart.
Images courtesy Upthink Lab
Three different skeletons were used for the animations. The actual fossil that had been scanned and positioned correctly, a composite skeleton created in CINEMA 4D based on the high-resolution scans and the reconstructed skeleton upThink modified and rigged for the show. Using Release 11, artists were able to have all three in one scene file.
To create the walking fossil assembly, Urquhart used CINEMA 4D?s PSR constraints to attach the fossil fragments to the walking rig. Animations showed floating fossils finding their places on the rig as it walked. "I think this part, in particular, really shows the capability of CINEMA 4D," says Urquhart. "All of the walk-cycle animations were created in just weeks before the show aired and I?m proud of how this came together."
