Imagine the green city of the not-too-distant future, say, a refurbished Singapore or an all-new, planned-out burg in India, China, or the Middle East. From high above the building-lined streets, fleets of bubble-canopied two-seaters scoot to, fro, and sideways in a coordinated fashion somewhat like schooling fish or flocking birds.
Each battery-powered people pod looks a bit like George Jetson’s egg-shaped sky-car except for the two well-grounded wheels below. And each seems to know how to avoid congestion and collisions at intersections because unseen wireless and sensor networks constantly link the vehicles and roadway infrastructure, keeping all the occupants safe and moving efficiently toward their destinations amid the high-tech concrete jungle.
Such is the vision for next-generation city transportation dreamed up several years ago by MIT professor William J. Mitchell and his Smart Cities research group at the Media Lab, and since pursued by General Motors executives Larry Burns and Chris Borroni-Bird.
Despite the intervening economic turmoil at GM, the company thought it time to reveal at the 2009 New York International Auto Show the initial results of its newly revealed, 18-month partnership with Segway of Bedford, NH, maker of the iconic, self-balancing Personal Transporter (PT), which was invented by the noted engineer Dean Kamen.
The first prototype of the team’s city people-pod concept, the PUMA, or Project for Urban Mobility and Accessibility, was on display amid the broad, deeply carpeted aisles of the Javitz Convention Center. Upon inspection, the new PUMA is basically a two-seat Segway with a roll cage and open plastic canopy. The whole thing, which is about half the size of a Smart ForTwo, resembles a runnerless rickshaw.
Like the upright Segway, the PUMA balances dynamically on two wheels by constantly adjusting wheel position. The vehicle maintains its balance by sensing its orientation and motion with angular rate sensors and accelerometers. As the PUMA leans forward, the system responds by driving the wheels just far enough ahead to finely maintain its balance, aping the way a unicycle is ridden.
The bare prototype weighs in at about 300 lb (136 kg) and can carry a bit more than double that. The seat and cabin sit atop a wheel-box that incorporates four lithium-ion battery packs, a digital energy-management system, and a pair of dc electric wheel motors.
Borroni-Bird, the PUMA project manager, said that the PUMA, which has a top speed of 35 mph (56 km/h) and a maximum range of 35 mi (56 km), would probably take from six to eight hours to recharge from a standard electrical outlet run for as little as $0.60 a charge.
I took a few laps in the new PUMA with Segway product designer, Derek Hugger, a couple of days ago. “Get in,” he says, as the vehicle hunkers down onto two small parking castors at the front. With the side safety bar down, the four-point harness in place, and my driver at the wheel beside me, it’s a tight fit in the little cockpit. In his hands Hugger holds the yoke, a large, joystick-like control stalk that resembles the Segway PT’s central upright handle.
He pushes the start button, advising me “to keep my legs flexible” as the machine raises the front auxiliary wheels a couple of inches off the ground and the platform assembly slides forward, rocking us up onto the two big, powered wheels. The sensation is like tilting backwards in a wheelchair and balancing (hopefully with someone to keep you from tipping over). Once the balance point is found, it’s just a matter of trusting the self-stabilization mechanism, something that one learns quickly when learning to ride a Segway PT.
Hugger pushes the control stalk forward and we wheel silently forward down the carpeted aisle, nimbly avoiding the passers-by. A turn of the yoke and the traction steering spins us around on a dime. He says that the controls on a new version of the PUMA that will arrive in the fall will operate differently.
We halt and the machine “bows” to let me out. Great fun zipping around the Javitz floor, but no test drives yet, unfortunately.
The PUMA could “fundamentally change how we move around cities,” said Burns, GM’s Vice-President of R&D and Strategic Planning.
If built, the vehicle would have a protective body and doors. It also would feature sophisticated safety sensors and controls, digital wireless technology such as short-range, vehicle-to-vehicle (V2V) communications, and, eventually, autonomous navigation systems that would handle much of the driving and parking, he explained.
Burns and Segway Chief Executive Officer Jim Norrod say that a production PUMA would probably be priced at from one-sixth to a quarter of what a car costs today. GM may begin testing vehicles on a university campus or other controlled area within a few years, Burns said.
Back to reality as I tread sooty, crowded New York City sidewalks back to work, musing on the irony surrounding the PUMA’s appearance in the Big Apple. In fact, current municipal ordinances keep the Segway PT off city streets and sidewalks for safety reasons. Clearly, the PUMA has a long way to go.