It's a scooter! It's a chariot! It's going to fall over!

December 4, 2001

It may be as close as we "muggles" get to Harry Potter's turbocharged broom.

After a year of hype and hoopla over "Ginger" and "IT," New Hampshire inventor Dean Kamen unveiled "Segway" yesterday, a motorized two-wheeled scooter with an ability to balance itself, leaving riders to focus on the road rather than staying upright.

Picture the back end of a child's tricycle, the steering shaft of a scooter, toss in some cutting-edge engineering, and you'll have a pretty good image of Mr. Kamen's latest contribution to human locomotion.

"It's the world's first self-balancing human transport," proclaims the wiry Kamen. "You stand on this, it goes. It's like putting on a pair of magic sneakers."

And who besides the perusers of Neiman Marcus catalogs might have an interest in Kamen's 12-m.p.h. chariots of tires?

"We've still got 13,000 letter carriers with walking routes," says US Postal Service spokeswoman Sue Brennan, who notes that the Postal Service is scheduled to take delivery of 20 scooters in early January. Carriers will be test-driving the units in Tampa and Fort Myers, Fla., Concord, N.H., and at Postal Service headquarters.

Kamen, whose credits for innovation include the portable dialysis machine and a self-balancing wheelchair that climbs stairs, says other commercial partners will also be testing grounds for his scooters. Among them are the city of Atlanta, the National Park Service, several police departments, and online bookseller Amazon.com.

"I think Segway potentially has a very large impact," says Woodie Flowers, a professor of mechanical engineering at the Massachusetts Institute of Technology and a close friend of Kamen's. "People in congested areas can have a new kind of mobility. People that have trouble walking can get around much more comfortably." And instead of locking up a vehicle in a parking lot, "you can just have the thing come with you."

The team, always mysterious, is holding details of the scooter's construction and technologies close to the vest because of patent considerations, Dr. Flowers notes.

"The key issue is self-balancing," achieved by tiny gyros tied to other systems, he allows. "There's a lot of very elegant engineering in that machine: everything from the tires, motors, and gearing to the sensor system."

For all the engineering, Segway's power plant is more prosaic that its pre-release media hype suggested. No fuel cells or heat-recycling Stirling engines here. Instead, motors and cutting-edge batteries provide the horsepower.

But given the progress made so far in blending the various technologies involved in Segway, incorporating additional power sources and motors into future devices shouldn't be difficult, Flowers says. "It's clear that Ginger, powered by batteries now and potentially by Stirling engines, could make a dramatic impact on our consumption of fossil fuels and production of CO2."

One key to consumer response, in addition to price and performance, is the kind of classification states, cities, and towns give these scooters as they take to roads and sidewalks. Kamen suggests that Segways could begin to reach the consumer markets by the end of next year, priced around $3,000. The version being tested by the Postal Service weighs about 80 pounds and will cost roughly $8,000. The consumer version is lighter, at 65 pounds.

A single battery charge can run the scooter for 15 miles over level terrain. And it's cheap to refuel, using just 10 cents of electricity in a six-hour charge, Kamen says.

Whatever its future, the project took on almost mythical proportions during its development. Early media coverage, triggered by an errant e-mail, heralded the coming of a revolution in transportation.

Yet to protect patentable technological secrets, Kamen refused to talk publically about the project. "My mother knew," he quips, "but mothers you can trust."

As the project progressed, industrial partners' interest grew. Several months ago, a Postal Service delegation from postal headquarters headed north to see how Ginger danced. "Even the deputy postmaster general got to try one," Ms. Brennan says.

Segway is the latest invention from Kamen's prolific laboratory, DEKA Research and Development Corp. near Manchester, N.H. The scooter is an evolution of technologies developed for "Fred," the self-balancing wheelchair capable of climbing stairs.

Kamen has taken his passion for robotics into schools, where 20,000 to 25,000 students a year now participate in competitions to build robots for specific tasks. With funding from NASA and corporations, Kamen's FIRST program hopes to inspire a new generation of kids to become scientists and engineers - and maybe spice up consumers' lives with a "Ginger" of their own.