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Long Range Plan for Transportation Technology is a
more recent article by the same author.
The Future of CarsCurrent Surface Transportation ChallengeGrowing urban vehicle
congestion, emissions pollution and vehicle fuel economy are related personal
transportation issues that various Administrations have sought to address for
decades. Measures taken have included CAFÉ standards (Corporate Average Fuel
Economy), higher federal and local excise taxes on gasoline, subsidies for
alternative fuel vehicles, and even taxes on luxury cars. Nevertheless, vehicle
congestion continues to grow through The Clinton Administration
focused on fuel economy and emissions, most notably in their public/private
venture with the Big Three automakers to produce a New Generation of Vehicles (PNGV)
capable of 80 miles per gallon of gasoline. However, well before such a vehicle
could be produced in America, Honda and On ·
Aim at longer range goals [than the PNGV initiative]
with greater emphasis on highway vehicle contributions to energy and
environmental concerns; ·
Move to more fundamental R&D at the component and
subsystem level; ·
Assure coverage of all light vehicle platforms; ·
Maintain some effort on nearer term technologies that
offer early opportunities to save petroleum; and ·
Strengthen efforts on technologies applicable to both
fuel cells and hybrid approaches; e.g., batteries, electronics, and motors. Predicted evolution of carsMultiples of current roadway capacity will be needed to keep traffic flowing smoothly, not only on highways but also on city thoroughfares. The Transportation Research Board produced a report in 1974 that gave substantial coverage to congestion alleviating dual-mode vehicles able to platoon on guideways, but also drive like normal cars. Developments during the 1990s suggest the outlines of a progressive evolution towards multi-mode vehicles with:
A brief look at each of the latter three modes will help define the best approach to building an effective new surface transportation infrastructure.
Platoon ModeDecreasing the following distances between cars using electronic, and possibly mechanical, coupling can greatly increase road capacity without building additional lanes. Of value at traffic bottlenecks, this capability would allow many cars to accelerate or brake simultaneously. Instead of waiting after a light changes to green for drivers ahead to react, a synchronized platoon would move as one, allowing an increase in lane throughput of up to 3-5X. Implemented first on major congested thoroughfares, platoons will require priority lanes and electronic signaling, and intersections outfitted to provide automatic warning of dangerous conditions (such as cars running red lights), but not major roadway reconstruction. Drivers would need a special license endorsement on account of the new skills required and the added responsibility when driving in the lead, but platoons would offer substantially shorter commutes during peak periods, the main incentive for purchasing platoon capabilities in a new vehicle, or possibly retrofitting existing ones. A secondary benefit is that on longer highway trips, vehicles could be mostly unattended while in following mode. See also: automated highway system
Driverless ModeAutomatically driven vehicles can already operate under certain constraints. Driverless vehicles that can autonomously join/leave platoons and safely park in designated “taxi-stands” would be able to offer service to non-drivers on major routes, at a cost comparable to bus service. The capability will inevitably progress to door-to-door service, particularly useful for the elderly, children and package delivery. See also: smart car
Guideway ModeLong platoons can travel very safely at high speeds on guideways that eliminate surface interference. Such guideways could carry 10,000 vehicles/hour at the current speed limit, five times more than a highway lane, and more at higher speeds. Elevated guideways would first be placed next to major thoroughfares and railways in congested areas. Both higher speeds and fuel efficiency can be achieved due to the much lower aerodynamic drag possible with platoons. On-demand and door-to-door travel at an average speed of 100MPH would be faster than air travel for trips of at least 300 miles, and vastly more convenient. Once built nationwide (see footnotes), the marginal costs would be low and at least 1/3 of airport traffic, all buses and passenger trains would be eliminated. Off-line Maglev with switching remains unproven but is much more likely to be economically viable for individual vehicles than for station trains because of up to 100X greater utilization of the expensive track. In the open air, speeds would still be limited to approximately 200-300 MPH, but marginal energy use and operating costs could beat domestic air on any overland route. Maglev sleepers could go coast-to-coast in 10-15 hours, and they would really be a great way to “see the country”. However, it seems most probable that the first national guideway system will use mechanical support, and that Maglev would come in the subsequent generation. Whether magnetic levitation or wheels are used, guideways would supply propulsive power, eliminating the need for vehicles to carry large energy stores and the means of converting them. Hydrogen fuel addresses propulsion only, while guideways also improve speed and safety, and use of the available rights-of-way more efficiently. .
Role of Government, Industry and CitizensWhile private concerns will construct the new generation of vehicles, and might even capitalize the infrastructure, the government’s role is to create the opportunity. Stages two and three can be attained with legislative help but relatively little public money but new laws will be needed to re-regulate liability and license drivers. Stage 4 guideways, especially Maglev, will require infrastructure expenditures that will cost on the order of one trillion dollars in the United States over twenty years, or about 20% of the cost of vehicles bought during that period. All governments and private industry need to take a
more imaginative approach to building surface transportation infrastructure for
the 21st century. Current “mass transit” approaches are woefully inadequate,
both because they ignore the average citizens' daily dependence on a personal
transportation vehicle and the new technologies that could sharply decrease
congestion related delays. Public and private attention is focused only on
enhanced fuel economies, fuel-cells
and limiting air
pollution. What is missing—and solely needed—are joint public/private
R&D efforts that advance efforts to take advantage of the electronics
revolution. If the surface
transportation infrastructure is properly developed, future Americans will
join ad hoc “trains” that form and disperse on an as-needed basis as people
“drive” to work, travel to another city, or go on long-distance vacations.
This will continue the long term trend of increasing mobility described by Jesse
H. Ausubel and Cesare
Marchetti in The
Evolution of Transport
Humongous thanks to Professor Jerry Schneider,
University of Washington for the ITS web site, and Tom Kirlin, Center
for the Study of the Presidency
[1]
Elevated
guideway costs for one prototype (www.ruf.dk) are estimated at about $7
million per route mile in
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