VALERIE Lehner and I stood in the cab of a Caterpillar Inc.
front-end loader as it circled the floor of an Arizona rock quarry,
scooped up a bucket full of stones, turned and dumped them.
But we weren't really standing in the cab. And we weren't
really in Arizona. And Lehner didn't really dump the stones, even
though it looked and sounded like stones dumping right in front of
That's because we were standing in what Lehner and other
researchers call "the CAVE."
The CAVE is a small room at the National Center for
Supercomputing Applications on the Urbana campus of the University
of Illinois. The supercomputing center is a mecca for applying
virtual reality technology to science and engineering problems.
CAVE is an acronym for Cave Automatic Virtual Environment. It's
also a reference to "The Simile of the Cave," a discussion of
perception, reality and illusion by the ancient Greek philosopher
Plato in "Republic."
A person standing in the Urbana CAVE and wearing a pair of
stereoscopic glasses enters a three-dimensional world of sights and
sounds created by computers.
This technology is similar to virtual reality games found today
in some video arcades, except for two things: its use and
sophistication. The CAVE is used for serious scientific research.
Sophistication? Virtual reality games are to the CAVE what Flash
Gordon's spaceship is to the Starship Enterprise.
"Sure it's `gee whiz' and `cool,' " said Kem Ahlers, a
researcher with Peoria-based Caterpillar. "But that's not why we're
here. It's a new technology we can use to make better products for
Lehner, Ahlers and other researchers have designed and built a
prototype of a front-end loader on a computer, then translated it
into a virtual front-end loader for display in the CAVE. In
essence, the CAVE has become their new test track.
The Caterpillar work may be the best example of using the CAVE
for applied science. But the CAVE has attracted researchers from
around the country who use it for basic scientific research, too.
They study such things as colliding galaxies, developing chicken
embryos, brewing thunderstorms and the changing shapes of surfaces
sculpted by mathematical equations. "We've got lots of ideas about
where we'd like to take this," Ahlers said. "The technology is only
just past its infancy."
A New Visual World
Using supercomputers as tools, the researchers "build" their
objects of study in computer simulations, be they molecules,
thunderstorms or star clusters. The simulations get translated into
realistic color images that change over time. In such a way, for
example, they can "visualize" how a simple cloud grows into a
Computer visualization of scientific phenomena has grown
dramatically over the past decade, powered largely by developments
at the Illinois center and other supercomputing labs established by
the National Science Foundation. The coins of the realm for this
trend are moving images displayed on computer screens and videotape.
The CAVE represents an evolutionary step into three dimensions.
"The CAVE - and virtual reality in general - is the first new
paradigm in 3-D image representation since the Renaissance, when
perspective was developed," said Thomas DeFanti, a co-inventor of
the CAVE who's based at the U of I's Chicago campus.
By displaying their simulations in the CAVE, researchers
examine their data by literally walking around and through it. This
allows them to use the most sophisticated computer ever developed
for analyzing visual data in three dimensions - the human eye-brain
That's important because these scientists work with a
tremendous amount of data. And the best way to find crucial
patterns in that data is to look at it.
Most researchers are "amazed" at the feeling of immersion they
get in the CAVE, DeFanti said. …