By Pat Brennan, NASA Jet Propulsion Laboratory/California Institute of Technology
Sea level scientist Eric Larour put on his helmet, took up his hand grips and went to work: diving straight into the interior of Alaska’s Columbia glacier, projected as a three dimensional rendering in his office at NASA’s Jet Propulsion Laboratory in Pasadena.
Free-standing cameras captured his movements as Larour opened his arms, turned to his side and appeared to manipulate invisible objects, but the view from inside the helmet was different. His gestures made the glacier expand to enormous size, then engulf him, while he separated slices of glacial imagery and stacked them in the air at his side for later reference.
Virtual reality has become a staple in electronics stores and a popular form of entertainment, with headsets immersing users in fully realized, 360-degree worlds. But Larour’s new VR system, set to make its debut at the American Geophysical Union conference Dec. 11, takes the concept much further. The goal is to turn virtual reality into something far beyond a game, or a thrill-ride: a tool that will be useful to scientists, allowing them to gain new perspectives on a rapidly changing planet.
“Can we bring this from a gimmick, a wishful dream, to efficient implementation of virtual reality for science?” Larour asks. “I don’t think anyone has done that convincingly yet.”
A specialist in cryospheric research, the study of Earth’s ice, Larour hopes one of the early applications of the new VR system, called the Virtual Earth System Laboratory, will target sea level science. The intricate and largely unmapped relationship between melting ice and rising seas is just beginning to yield up its secrets.
By constructing accurate computer models of glaciers, ice caps and ice sheets, and evolving them forward in time, researchers can reveal the hidden plumbing of water-flow beneath melting glaciers. They can trace the infusion of meltwater into Arctic and Antarctic seas, track shifting ocean currents and even estimate how much of the sea-level-rise in New York can be attributed to glaciers in northwestern Greenland.
The new system, in a sense, places these sophisticated models on steroids. They can be uploaded into a VR “engine,” in this case built on a platform called Unity; suddenly the scientist is standing on the ramparts of a glacier or staring up through thousands of feet ocean, viewing striations of color representing temperature profiles for columns of seawater.
Digital analogs of Larour’s office furniture – desks, chairs, cabinets – also will be added, so he can avoid bumping into them.
“You’re standing in your office, outputting results,” Larour said. “You’re under it, over it, massaging it, chopping, slicing it. You can look at the data – ‘There’s something funky here!’ – strip away the slice, look at a second projection on that slice. It’s literally ‘Minority Report.’”
Unlike in the 2002 Tom Cruise film, however, a headset and hand grips must be used to open a series of windows in three-dimensional space. The system was developed by Larour and JPL’s Virtual Earth System Laboratory, which also lent the new VR tool its name.
“Developing (this tool) for VR opened up exciting new data visualization techniques that had been thought impossible a few years back,” said Christian Alarcon, who co-developed the VR engine with Joe Roberts. Both are data visualization developers at JPL.
The VR experience, Larour says, sometimes can be disorienting. Hovering in the background of one simulation is a huge planet Earth, which can be turned and expanded until you are on (or below) the surface at a desired location.
“The background planet Earth is gigantic in space,” he said. “I forgot it was a simulation. It was like I was floating in space.”
He acknowledges that the system’s stated purpose also is its largest hurdle. Making it a true scientific tool, rather than an intriguing plaything, requires far more physical accuracy and precision than an invented universe of, say, interplanetary monsters that must be slain with high-powered weapons.
“This is not a physical engine in the game technology sense of things,” Larour said. “This is a true physics engine.”
If it’s raining in a game, the rain only has to have an appearance that matches the player’s expectation – to “look right.” In scientific VR, glacial melting must be linked with, say, sea level rise in mathematically plausible ways.
“It’s really impressive when you see an ice cap rendering in the right way, and the sea level signal from it,” Larour said.
Scientists also must be able to gain real insights, and generate concrete results, if the tool is to be useful to the broader scientific community.
He says he’s already seen a glimmer of such usefulness in the renderings of the system so far.
“Dataset discovery is not easy in science,” he said. “Even simulations can be quite an extensive amount of data. (But) I’m finding it very easy to walk through this data and observe things on the fly that would be very useful. It’s not easy on a flat screen, showing slices and slices of a 3-D dataset.”
And Larour is already thinking about new ways to use the VR system, including projection on an interactive globe such as “Science on a Sphere.”
“I think we’re opening the gates to brand new applications of virtual reality,” he said.
Find Eric Larour and his team demonstrating the new VR capability at this year's AGU Fall Meeting at the NASA booth.