UC Irvine computer scientist Crista Lopes was happy to do all her work in the real world - until February, that is.

Now she also devotes time to programming in the computer-based world Second Life, where she is creating software to control a virtual rapid-transit system called SkyTran. Her software keeps SkyTran's virtual cars from getting into virtual collisions at virtual interchanges of virtual tracks.

After the control software is ready in Second Life, her plan is to transfer it to a real-world version of SkyTran, proposed by the Irvine-based transportation company Unimodal Inc.

In the programming process, Lopes said, she discovered that the simplified physics of Second Life are close enough to the physics of the real world that Second Life can be used as an inexpensive simulation tool by small- to medium-sized companies. It's a low-cost alternative to the sophisticated simulation programs in use by industrial designers at big-bucks enterprises such as NASA and the military, as well as Boeing and other aerospace contractors.

"She's onto something," said Chris Perkins, chief executive of Unimodal. The virtual version of SkyTran has already been useful in addressing urban-planning issues, such as demonstrating how close the tracks could be to buildings and vegetation without making passengers uncomfortable, he said.

Unimodal also concluded that SkyTran's express track shouldn't run directly above the loading platform, because that setup looked as if it would make passengers uneasy, Perkins said.

VIRTUAL NEW WORLD

Until February of this year, Lopes had no idea that she'd be working in a 3D digital world where people can fly. Then a friend introduced her to Second Life, where computer users can visit, chat, shop, buy land, build houses, design clothing and - oh, yes - teleport themselves and control the movements of the sun. Moving through it is like visiting "World of Warcraft" or other multiplayer computer games, except there are no fights, no winners and no losers.

Lopes enjoys many of the flight-of-fantasy features that have attracted 11 million users to Second Life since Linden Lab of San Francisco launched it in 2003. She chose as her online character, or avatar, an elf maiden named Diva Canto, who has wings and red hair that the real-world computer scientist envies.

But a different aspect of Second Life attracted her more.

"Once I found out its programming capabilities, I was hooked," said Lopes, who is an associate professor of informatics at the Bren School of Information and Computer Sciences at UCI.

In March, she and William Cook, a colleague at the University of Texas in Austin, started work on a program to search Second Life just as Google searches the Internet. In June, the two computer scientists - represented by their avatars: petite, red-haired Diva Canto and tall, slim, white-haired Felix Wakmann - launched SLBrowser, which is available at SLBrowser.com and in Second Life.

In May, her interest in Second Life led her to SkyTran, a solar-powered, magnetic-levitation transit system that Unimodal proposes to build wherever it can find enthusiastic backers. Among its proposals are a network of two-person cars on elevated tracks built throughout Irvine, a similar transit line connecting LAX and downtown Los Angeles, and a SkyTran network connecting Northern and Southern California.

"They're a startup and they needed help," Lopes said. "They contacted UCI's Institute for Software Research, and I contacted them back."

MORE THAN CAD

Over the summer, she and two graduate students, Anton Popov and Lorraine Kan, built the virtual version of SkyTran on TechCoast, a virtual island in Second Life that's owned by the UCI school of computer sciences.

In the virtual construction process, which used specs from Unimodal, the researchers found ways to improve the SkyTran design, Lopes said.

"The angle of the bricks was wrong, which would have been detected in any computer-assisted design tool," she said.

But a standard CAD (computer assisted design) program wouldn't have spotted two other design issues that were apparent in Second Life, she said.

One was the alignment of the express track directly over the platform, which would be safe, but feels unsafe. The second issue arose from the clear "glass" used in the Second Life pods. Unimodal officials said that, if that were used in a real-life SkyTran pod, it could expose passengers to a fast, repetitive pattern of SkyTran track components moving by, which could produce epileptic seizures in some people.

Ricardo Morla, a post-doctoral fellow who studied with Lopes at UCI last year, is working on transferring the Second Life programming language into a Linux computer system. That will allow the control software that Lopes creates for the virtual SkyTran to be used in a real-world computer to control a real-world SkyTran.

Lopes foresees doing further work on the virtual SkyTran system.

"Eventually, Unimodal will want to build a system for a whole city. They'll have to do a simulation of it first," she said.

So far, UCI computer scientists' work for Unimodal has been based on "pure academic interest," Lopes said. "I wanted to see to what extent Second Life could serve as a tool for real-world engineering design."

"I had no idea if it would work," she said. "I thought there was a 50-50 chance that Second Life would be a good-enough simulation."

"It turns out that it's very powerful."