Sustainability: ULTra PRT


For years, science fiction has proposed driverless transportation—but now it’s possible to see what such a system might look like, as Alan Swaby discovers.

 

How do you solve the impasse that is urban public transport? Most people recognise that pollution and congestion in city centres could be lessened by switching to public transport; and yet a crowbar couldn’t prise most of us out of our cars.

Martin Lowson, founder and president of ULTra PRT has long been of the opinion that the present system, which relies so heavily on bus usage, simply doesn’t fit the bill. In his quiet moments, while working in the United States—first as project leader on the Apollo space programme and then later as chief scientist at Westland helicopters, Lowson applied his ‘system engineering’ training to the problem and developed the concept of an automatic, driverless vehicle capable of carrying four adult passengers and their possessions.

“Ask travellers what they want from an urban transport system,” Lowson explains, “and it’s obvious that the biggest incentive would be not having to wait for a bus. Then people want to be able to get to exactly where they are going in comfort and without stops. In other words, they are describing their cars. So the system we offer needs to be as good as, if not better than, a car.”

In the 1990s Lowson took up a professorship at the University of Bristol and began putting his ideas into practice. With various grants from the Science and Engineering Research Council, the Department of Transport Seedcorn Programme and the Rees Jeffreys Road Fund, ULTra (Urban Light Transport) PRT (Personal Rapid Transit) gradually began to take shape.

“The idea of PRT is not new,” admits Lowson. “Forty years ago the concept was being discussed but it was an idea before its time. With modern IT systems and electronic rather than mechanical guidance, PRT has now become achievable.”

The breakthrough came in 2000, when ULTra PRT won a UK government innovative transport contract worth £2.7 million, to design and develop a full working prototype. The wrinkles were ironed out by four prototype vehicles zipping around a one kilometre test track in Cardiff, which included all the features of a practical application. 

In the meantime, managers at BAA had been looking for a mass transit alternative to buses at Heathrow and concluded that none existed—but when they were introduced to ULTra PRT, they thought so much of it that they bought into the business and by 2006, had commissioned a system to service Terminal 5 (that was currently being built) with a connection between the business car park and the terminal.

The two kilometre link was completed some time ago but still smarting from the bag-handling fiasco, BAA insisted on the highest possible standards of testing and reliability before getting the public involved. Hundreds of journeys were made using Heathrow employees as guinea pigs until travellers were invited to use ULTra PRT in April. It’s still early days but the system has been operating for 22 hours a day since then and has so far proved virtually 100 per cent reliable.

Over the years, cars have become increasingly complex, but Lowson believed that the key to making ULTra PRT work was to have no more technology in use than necessary. Consequently, the electronics do no more than register a destination and guide the car to it. Nor is there anything much in ULTra PRT that had to be designed specifically for it. All the components are off the shelf, leaving only the chassis and the body shell needing to be custom made by AARK—specialists in such mass manufacturing.

Maximum speed has been limited to 40 kph (25 mph) to improve safety, but this is more than enough to reduce comparable trip times by a factor of between two and three compared to cars or buses in a congested locality. More to the point, the modest top speed means that minimal energy is required. Compared to a 60kW Prius electric motor, for example, ULTra PRT’s motor is rated at just 7kW and actually draws only 2kW at 40 kph.

Lowson has received lots of interest from city managers on how ULTra PRT could be integrated into their existing infrastructure. “Most models for public transport,” he argues, “follow the mass transit approach—city tramways or light railways. But they can only be viable when they are carrying lots of people and of course, need a driver. ULTra PRT takes a different view and proposes that mass transit should be on a small, virtually individual basis. Otherwise we will never switch the 80 per cent of journeys that are currently made in cars.”

Even a city so environmentally sensitive as Bath has expressed interest in ULTra PRT, and it has even won the blessing of the politically powerful Residents’ Committee which could see a car-free city centre, should ULTra PRT be employed. 

From a layman’s point of view, shaped as it is by motoring programmes such as Top Gear, the one drawback would seem to be ULTra PRT’s need for tracks and with that, an inherent limit in just how flexible a network it could provide. Lowson is far from fazed by this criticism: “It’s one thing allowing technology to guide a vehicle on a motorway,” he says, “but it would be far more difficult to make it work driverless in the complexity of a city centre where cars and people have to co-exist. Getting safety approval and public acceptance for such technology would be altogether different.”

That said, installation at Heathrow required negotiating a car park, two roads that carry 100,000 cars, buses, taxis and coaches per day, major water storage areas and taxi ranks, as well as going alongside airside, where planes are being loaded and unloaded. If it can work here, it can easily co-exist in the busiest city.

There’s no doubt that ULTra PRT has so far proved popular with all who have tried it—the inherent good looks and novelty factor can’t fail to interest. But as with all attempts to get individuals out of their cars, it will only work if the commissioning city is brave enough to give it a proper test bed and price the service attractively.

In the meantime, there are some people lucky enough to be sampling what the future might be like—and they are those passengers flying out from Terminal 5 at Heathrow. http://www.ultraprt.com/