There were four personal rapid transit (PRT) –related papers and/or presentations at the 89th Annual meeting of the transportation Research Board (TRB) this year.
Martin Lowson, President of Advanced Transport Systems Ltd., (the developers of the ULTra PRT system) delivered an interesting presentation titled Preparing for PRT Operations at Heathrow Airport, United Kingdom. He showed a BBC video (not available in the US) where the reporter claimed to be the first member of the public to ride the system. ATS is still confident they can build complete systems for $10M to $15M per one-way mile.
Heathrow PRT Maintenance Facility
Professor Lowson said that BAA considered PRT to be the only practical solution to their many surface transportation problems. In addition to financial benefits, PRT offers a higher level of passenger service, environmental benefits and a more efficient use of space. He indicated they are well into phase Phase 3 of the following testing and implementation progress chart. 
ATS has developed 429 system documents defining: Operations procedures (162), Safety Management System (75), Internal Management (74), Training modules (118). Professor Lowson showed the following slide depicting their safety verification process.
ATS has been surprised to find that passengers expect to share rides and want to wait for others to join them. The ULTra PRT system at Heathrow is in the final stage of test and commissioning and is on target for full passenger operations in mid 2010.
Steve Raney of Cities 21.org presented a paper titled Efficient Edge Cities of the Future and uniquely written in storey form that begins as follows: “October 5, 2020. Hello, my name is Emma Raney. Compared to typical suburban living, I live a life with lower cost of living; more free time; better work/life balance; stronger, more supportive, and more diverse local community; and one-quarter of the energy consumption. My community (SRP) produces emissions well below Kyoto protocol standards.”
The storey continues to describe life in a community that goes to considerable lengths to promote sustainability. Needless to say, the PRT system (a shuttle bus on steroids) is a key part of the community. However it is very much integrated into numerous other forms of accessibility.
Comprehensive Integrated Mobility
“SRP has a personal rapid transit (PRT) system, and I take that to many destinations… I carpool to church… SRP’s PRT connects to PRT systems in other large Silicon Valley office parks (there are 10 others). Via this connection, I connect to a larger variety of stores… Very rarely, I get a little carried away and I end up with a bunch of large items to schlep home. Large wheeled carts are available at some stores. I wheel the cart and items onto PRT vehicle, take my items home, then I wheel the empty cart onto another PRT vehicle where it is re-deployed… I take commuter rail to see Sharks hockey…When I go to Stanford for an event, I usually PRT with bike (on occasion I combine PRT with a foldable electric scooter). To get to places, I walk significantly more than a typical suburbanite – I generally travel the first and last trip segment on foot.”
Robert Baertsch, Nasa Ames Research Center presented a paper titled Renewable Energy Utilization Advantages of Maglev-Based Personal Rapid Transit. “This paper examines the advantages that Personal Rapid Transit (PRT) exhibits in the utilization of renewable energy from usage, distribution, and generation perspectives. The paper also looks at different types of PRT and how they impact the load on the electrical grid. Recent advances in power electronics and maglev technology allow for the design of a novel MPRT system characterized not only by exceptionally low power requirements, but also by a unique capacity to incorporate energy distribution and storage infrastructure into the greater transportation architecture.
MPRT prototype at NASA Ames, Moffett Field, CA
A hypothetical hybrid MPRT design incorporating energy storage and transmission capabilities is presented. Additionally, thorough carbon dioxide and cost analyses are undertaken in order to more fully understand the wide spectrum of benefits of an MPRT solution in comparison to Conventional Vehicle (CV) and Plug-in Hybrid Electric Vehicle (PHEV) approaches. We conclude that an MPRT system not only offers significant advantages over other technologies in efficiently utilizing renewable energy, but, moreover, that the unique potential of this concept to incorporate power transmission, storage, and generation infrastructure makes it ideal for addressing the energy challenges of the near and distant future.”
The system is anticipated to operate at 40 mph in downtown areas and at highway speeds elsewhere. The upper speed limit is 150 mph. Linear induction motors are built into the guideway. An equivalent 325 mpg and capital costs under $10M per one way mile (up to $18M including integrated photovoltaic panels and power distribution) are anticipated.
John Lees_Miller, University of Bristol, United Kingdom presented a paper titled Theoretical Maximum Capacity as a Benchmark for Empty Vehicle Redistribution in Personal Rapid Transit. “A Personal Rapid Transit (PRT) system uses compact, computer-guided vehicles running on dedicated guideways to carry individuals or small groups directly between pairs of stations. Vehicles move on demand when a passenger requests service at his/her origin station. Because the number of trips requested from a station need not equal the number of trips ending there, some vehicles must run empty to balance the flows. The empty vehicle redistribution (EVR) problem is to decide which empty vehicles to move, and when and where to move them; an EVR algorithm makes these decisions in real time, as passengers arrive and request service.
This paper describes a method for finding the theoretical maximum demand (with a given spatial distribution) that a given system could serve with any EVR algorithm, which provides a benchmark against which particular EVR algorithms can be compared. The maximum passenger demand that a particular EVR algorithm can serve can be determined by simulation and then compared to the benchmark. The method is applied to two simple EVR heuristics on two example systems, and the results suggest that this is a useful method for determining the strengths and weaknesses of a variety of EVR heuristics across a range of networks, passenger demands and fleet sizes.
This paper demonstrates a new method for the evaluation of empty vehicle redistribution (EVR) algorithms, providing an absolute measure of their performance according to a metric based on the capacity region for a given network. The capacity region is defined as the set of OD matrices which are feasible in the sense that their demands can be met without passenger queues growing indefinitely. It describes the maximum possible demand that a particular system could serve with an ideal EVR algorithm, and hence acts as an absolute benchmark against which different EVR algorithms can be compared.
The ability to compare and evaluate EVR algorithms is important for the successful operation of highly-connected PRT systems… In normal PRT operation, the minimization of passenger waiting time is usually the priority, and hence one could expect an EVR heuristic which prioritizes this…to be in operation. At times of high demand, however, when the vehicle fleet is stretched and there are passengers waiting at numerous stations across the network [this]… often moves vehicles too far. One would instead prefer an algorithm which prioritizes the efficient use of the vehicle fleet…
This analysis also shows how both the network topology and the spatial distribution of the demand can affect EVR performance, even when line congestion is ignored…The proposed method allows for the absolute assessment of EVR algorithms in terms of throughput, subject to the modeling assumptions…There are a number of alternative heuristics already present in the literature … and an analysis of these algorithms using this evaluation tool is a natural next step.”
