It will never be mass-produced looking exactly like this, but the car you might someday drive to work exists today as a plywood-and-steel vehicle with three wheels, a 7-horsepower biodiesel engine and a front suspension cannibalized from an ATV.

Students at the Rhode Island School of Design and Brown University designed and built the car, called the Coda, which carries two people and doesn’t go over 35 mph. But size and speed were not the ambition –– being friendly to the urban environment and to the pocketbook were. And even if you never get to drive a Coda, its value as inspiration would make it a success.

Michael Lye, an industrial-design professor at RISD, and Chris Bull, an engineering professor at Brown, led the group of 28 students, who worked in shops at RISD and at Brown, where the Coda is now parked. The idea began with what a friend of Lye’s witnessed on a visit to Phnom Penh, Cambodia.

“He had photographs of whole families, four people, on a motorcycle –– and the person on the back might be carrying a 19-inch TV,” Lye says. A dangerous mode of transportation, but an economical one. Not to mention that many motorcycles fit into the space occupied by a few SUVs. It got the professor thinking.

“We’ve got this whole class of vehicles that we call cars,” he figured, “and then we have a few that are called motorcycles or scooters. But really, there seems to be a need for something else, something in between those two categories.” Something simpler and cheaper than a Smart car, which is already on the road.

“Looking toward the future,” Lye says, “I’m thinking that one of the things we have to do is provide lots more variety so people can choose vehicles that are most appropriate for the kind of transportation they need. The way people buy cars now in America –– they buy the biggest thing so that one weekend a year, they can load stuff from Home Depot into it. Or something to go hiking for one weekend.

“They only do that because they don’t want to have three, four or five vehicles. They can’t afford it. But what if some of them are so cheap that for their daily commute they can really have a commuter vehicle that works?”

Brown professor Bull, who’s collaborated with Lye on other projects, agreed.

The professors asked the students to design with Providence in mind: getting around inside the city, and commuting from nearby suburbs. “We pushed the urban, small-scale part of it,” Bull says.

Students were divided into seven groups: chassis, body, drive train, suspension, controls, human interface, and business/marketing. They decided on three wheels for enhanced maneuverability in tight city confines, and biodiesel power to reduce carbon emissions. With performance of better than 100 miles per gallon, one tankful of vegetable oil could provide transportation for weeks. And the Coda is easy to repair.

The students made some of the car’s components in Brown and RISD shops, and bought others off the shelf –– the clean-burning engine, made in Germany, for example. And an ATV, found on craigslist. Total cost was around $3,000, excluding labor, which, of course, was free.

When they were done, at the end of last year, they had a car that weighed less than 500 pounds and was 98 inches long overall and five feet wide. It successfully completed a short test run near RISD’s industrial design building on South Main Street.

“We started it up, it ran,” Lye says. “The engine nearly shook itself off the mounts because we forgot to tighten the bolts. Little things like that that you expect in a shakedown run. But it was driven.” More tasks await, among them completing the body, replacing plywood seats with upholstered comfort, and building a custom-designed suspension. But the essence of the car is here, today.

Lye estimates that if Coda were ever manufactured, it would retail for about $2,500. If Coda and Coda-like vehicles ever became popular, Lye says, road maintenance costs theoretically would decrease, since light vehicles are less punishing to pavement. Traffic congestion in cities would ease, making for faster commutes using less fuel. It might be possible to reclaim some streets for green use (as happened in Boston when they buried the old Central Artery as part of the Big Dig project).

But RISD and Brown are not in the car-making business, and it would be up to someone else to manufacture the Coda. Lye and Bull do not think that’s likely.

Rather, Lye says, they see the Coda as a concept car that will “inspire other companies and inspire people to say, ‘Hey, I’d drive that! That would be cool, I’d really like that.’ And to generate some market demand for different kinds of vehicles.”

Says Bull: “If somebody takes some of the ideas they see and incorporates them into some vehicle, we think that’s one measure of success.”

More on Coda is at www.risd.edu/student_projects_gas.htm

And at whycoda.com

G. Wayne Miller welcomes suggestions for future What’s Next stories.

gwmiller@projo.com