ULTra

Personal rapid transit

Personal rapid transit , also called podcar, is a public transportation mode featuring small automated vehicles operating on a network of specially built guide ways...

system developed by ULTra PRT, (formerly known as Advanced Transport Systems). The first public system using ULTra has been constructed at London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

's Heathrow Airport

London Heathrow Airport

London Heathrow Airport or Heathrow , in the London Borough of Hillingdon, is the busiest airport in the United Kingdom and the third busiest airport in the world in terms of total passenger traffic, handling more international passengers than any other airport around the globe...

, and has now opened to the public.

To reduce fabrication costs, the ULTra uses largely off-the-shelf technologies, such as rubber tyres running on an open guideway. This approach has resulted in a system that ULTra believes to be more economical; the company reports that the total cost of the system (vehicles, infrastructure and control systems) is between £3 million and £5 million per kilometre of guideway.

Inception

The system was originally designed by Martin Lowson and his design team, Lowson having put £10 million into the project. He formed Advanced Transport Systems (ATS) in Cardiff

Cardiff

Cardiff is the capital, largest city and most populous county of Wales and the 10th largest city in the United Kingdom. The city is Wales' chief commercial centre, the base for most national cultural and sporting institutions, the Welsh national media, and the seat of the National Assembly for...

to develop the system, and their site later served as the location for buildings its test track. ULTra has twice been awarded funding from the UK National Endowment for Science, Technology and the Arts (NESTA

NESTA

The National Endowment for Science, Technology and the Arts is an independent endowment in the United Kingdom established by an Act of Parliament in 1998....

). Much of the original research on ULTra was done by the Aerospace Engineering department at the University of Bristol

University of Bristol

The University of Bristol is a public research university located in Bristol, United Kingdom. One of the so-called "red brick" universities, it received its Royal Charter in 1909, although its predecessor institution, University College, Bristol, had been in existence since 1876.The University is...

during the 1990s. Recently the company renamed itself to "ULTra PRT Limited" to better reflect its primary business, and moved its corporate headquarters to Bristol

Bristol

Bristol is a city, unitary authority area and ceremonial county in South West England, with an estimated population of 433,100 for the unitary authority in 2009, and a surrounding Larger Urban Zone with an estimated 1,070,000 residents in 2007...

Past PRT designs

The personal rapid transit, or PRT, originally developed in the 1950s as a response to the need to move commuters in areas where the densities were too low to pay for the construction of a conventional metro system. Using automated guidance allowed headway

Headway

Headway is a measurement of the distance/time between vehicles in a transit system. The precise definition varies depending on the application, but it is most commonly measured as the distance from the tip of one vehicle to the tip of the next one behind it, expressed as the time it will take for...

s to be shortened, often to a few seconds, but in some cases fractions of a second. This increases the route capacity, allowing the vehicles to become much smaller while still carrying the same passenger load in a given time. Smaller vehicles in turn would require simpler "tracks", smaller stations, and lowered capital costs as a result. Smaller towns and cities that could never hope to fund a conventional mass transit system could afford a PRT, and the concept generated intense interest.

Numerous PRT systems were designed in the late 1960s and early 1970s, many as a result of the publication of the highly influential HUD reports

HUD reports

The HUD Reports were a series of studies in mass transit systems, funded by the Urban Mass Transportation Administration department of the United States Department of Housing and Urban Development...

. In general, these systems intended to use small four to six passenger vehicles, but most evolved to larger designs over time (see Alden staRRcar

Alden staRRcar

The Alden staRRcar, for "Self-Transport Road and Rail Car", was a design for a personal rapid transit system designed by William Alden in the 1960s...

). As they did so, vehicles and tracks grew heavier, capital costs rose, and interest dropped. In the end, only one production PRT system was ever installed, the Morgantown PRT, a government-funded demonstration system to prove the concept. Originally derided as a white elephant

White elephant

A white elephant is an idiom for a valuable but burdensome possession of which its owner cannot dispose and whose cost is out of proportion to its usefulness or worth...

, the Morgantown system has since proven itself both reliable and relatively low-cost.

In the time since the Morgantown system was installed, general technological improvements have led to a number of ways to lower the cost of implementing a PRT system. One of the simplest, but most profound, was the development of more efficient, reliable and quick-charging battery systems. Older PRT systems used electricity fed from track-side conductors in a fashion similar to a conventional metro, but these can be eliminated in favour of batteries that quickly charge up at stations or small charging strips along the route. Another change is the moving of the guidance logic from centralised computers to on-board systems of dramatically improved performance, allowing the vehicles to steer and switch themselves between routes on their own. This eliminates the need for a track-mounted guiderail able to steer the vehicle (see, for instance, the Ford ACT

Ford ACT

Ford's ACT, short for Automatically Controlled Transportation or Activity Center Transit, was a people mover system developed during the 1970s. One interesting feature of the ACT is that it allowed bi-directional travel on a single rail—cars passed each other by switching onto short bypass lanes on...

). Together, these changes mean the vehicle no longer needs strong mechanical contact with the guideway, which can be dramatically reduced in complexity.

In the case of ULTra, the guideway can consist of as little as two parallel rows of concrete barriers, similar to the bumpers found in a parking lot

Parking lot

A parking lot , also known as car lot, is a cleared area that is intended for parking vehicles. Usually, the term refers to a dedicated area that has been provided with a durable or semi-durable surface....

. The vehicle uses these for fine guidance only; it is able to steer itself around curves by following the barriers passively. No "switching" is required on the track either, as the vehicles can make their own turns between routes based on an internal map. Since the vehicles are battery powered, there's no need for electrification along the track. Instead the vehicles recharge when parked at the stations. As a result, the trackway is similar in complexity to a conventional road surface - a light-duty one as the vehicles will not vary in weight to the extent of a tractor-trailer. Even the stations are greatly simplified; in the case of ground-level tracks, the lack of any substantial infrastructure means the vehicles can stop at any kerb. Stations at Heathrow resemble a parking lot with diagonal slots, with a rain shield similar to the awnings at a gas station.

For all of these reasons, the capital costs of the ULTra system are dramatically reduced compared to older systems. A 1980s Canadian estimate places the price of a conventional underground metro system at $75 to $80 million per kilometre, about CA$190 million in 2008 dollars. The Morgantown PRT came in well over-budget and has a demonstrated cost of just over US$9 million per km in 1979, equivalent to about US$28 million in 2008. Expansion plans from just after 2000 puts the costs of additional track at US$30 to US$40 million per mile. However, the company estimates that an ULTra system can be installed, including vehicles and stations, for £3 to £5 million per km of track, about US$5 to US$8 million, . This cost includes extensive sections using elevated guideways, which are much more expensive than at-grade versions.

Vehicles

The electric-powered vehicles have four seats, can carry 500-kilogram payload, and are designed to travel at 40 kilometres per hour (25 mph) at gradients of up to 20-percent, although the company has suggested limiting operating routes to 10-percent gradients to improve passenger comfort. The vehicles can accommodate wheelchairs, shopping trolleys and other luggage in addition to the passengers.

Each pod is powered by a battery pack providing an average two kilowatts of power and adding 8-percent to the gross weight of the vehicle. Other specifications include a 5-metre turning radius, an energy requirement of 0.55 mega-joules per passenger-kilometre, and running noise levels of 35 dBA at 21.6 kilometres per hour and measured at a distance of ten metres.

The company has also developed designs for a freight version of the vehicle. This has the same external appearance as the passenger version, but its entire internal space is adapted to host a cargo capsule. These can be valuable in airport environments, where the network can be used to haul small freight.

Test track

The one-kilometre ULTra test track was launched in January 2002. The $4 million funding for the test track came from various sources in the United Kingdom government. One electric vehicle was demonstrated running at speeds up to 25 miles per hour. Accurate stopping was demonstrated and the vehicle ascended and descended a steep gradient. A single, rudimentary ground level station was shown.

Most of the test track guideway is at ground level. It is stated that in a commercial application, 90-percent or more of the guideway might have to be elevated. This elevated guideway is about 1.5 metres wide. According to a study of a hypothetical city-based installation, consisting of 19.8 kilometres (12.3 mi) of guideway (89% elevated), the total cost of ULTra track and associated civil engineering works is estimated to be £2.9 million per kilometre ($8.7M/mi). Per-station costs were estimated to be £0.48-million ($0.89M). Vehicle costs were not considered in this study.

Heathrow Terminal 5

Terminal 5 at London Heathrow Airport

London Heathrow Airport

is served by a 3.9 kilometres (2.4 mi) ULTra PRT system that connects the terminal to its business passenger car park, just north of the airport. The line has been built on behalf of BAA, the airport's owner and operator.

Construction of the guideway was completed in October 2008. The line is largely elevated, but includes a ground level section where the route passes under the approach to the airport's northern runway. Following various trials, including some using airport staff as test passengers, the line opened to public usage in May 2011. At that time it was described as a passenger trial. As of September 2011 it is fully operational and bus service between the business parking lot and Terminal 5 has been discontinued.

The developers expect that users will wait an average of around twelve seconds with 95-percent of passengers waiting for less than one minute for their private pod which will travel up to 40 kilometres per hour (24.9 mph). If the pilot project is successful, BAA have indicated that they will extend the service throughout the airport and to nearby hotels using 400 pods.

Gurgaon City transport, India

In March 2010, the government of Haryana

Haryana

Haryana is a state in India. Historically, it has been a part of the Kuru region in North India. The name Haryana is found mentioned in the 12th century AD by the apabhramsha writer Vibudh Shridhar . It is bordered by Punjab and Himachal Pradesh to the north, and by Rajasthan to the west and south...

said that they are looking into a proposal to deploy the ULTra PRT system for rapid commuter transport in the city of Gurgaon

Gurgaon

Gurgaon is the second largest city in the Indian state of Haryana. Gurgaon is the industrial and financial center of Haryana. It is located 30 km south of national capital New Delhi, about 10 kilometers from Dwarka Sub City and 268 km south of Chandigarh, the state capital...

. The city is looking at over 10 to 12 individual routes covering a total distance of approximately 100 kilometres (62.1 mi).

External links

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