Requirements and Rationale
Higherway System Requirements
The system requirements are derived from the primary goals; for a metropolitan area: reduce traffic congestion, improve people's
mobility, and make a profit for transit system owners. (If the owner is
a non-profit or government organization the profit could be used to pay
for paratransit or other service). A secondary goal is to gain >30%
market share of commuters. Based on these goals, there is a general
requirement that for at least 30% of commuters the transit system must
provide a quicker, cheaper, safer, more reliable way of going where
they want to go than any alternative mode of transportation they may have.
Means must be provided to clear the track of vehicles
in case of accidents, power failures and other equipment breakdowns. Vehicles
must be able to back up. Means must be provided for riders to leave the
vehicles and return to ground level at any point along the track if the
vehicles become immobile for more than a half hour due to accident or failure.
PAT systems planned for installation in the USA must comply
with the requirements of the Americans with Disabilities Act for demand-response
operations of small vehicles. The system must be usable by blind and deaf
people and it must give essentially the same level of service for a person
in a wheelchair plus attendant or guide animal as it does for able-bodied
Personal automated transport can satisfy the above requirements.
If implemented properly, an electrically-powered, computer-controlled,
grade-separated, system with small, fast vehicles and off-line stops will
be safer and more reliable than any of the present transit modes which
compete with and collide with surface traffic. (Elevated monorail vehicles
never bump into pedestrians, bicyclists, cars, trucks or buses.)
Some Design Rationale
- Vehicles suspended under the tracks run on dry surfaces
in all weather conditions and are not hindered by snow or ice unless the
weight of the ice is so heavy as to limit acceleration or freeze the doors
- Allowing vehicles to lean in cross winds and curves reduces
stress on the guideway and vehicle and makes bicyclists, motorcyclists,
and airplane pilots happier.
- To compete for commuters in automobiles going from suburb
to suburb on freeways at 27 m/s (60 m.p.h.), we are designing for 45 m/s
(100 m.p.h.) arterial line speed for our PAT vehicles. For many, this higher
speed will make up for the times required to go to the origin stop and
from the destination stop to the destination. For the fare to be competitive
and still make a profit for the transit system operator, the system must
be designed, built and operated for low life cycle cost and high customer
satisfaction. The high speed is important to gain more passenger kilometers
per vehicle for economy, but at 45 m/s aerodynamic drag is significant
and a streamlined shape with small frontal area is needed to keep the power
- Relatively few automobiles carry more than one commuter,
so designing PAT vehicles for more than two adults will not gain much market
share compared to a two-passenger vehicle.
- Adding dualmode capabilities enables the Higherway system
to serve larger areas with lower population densities economically and
gain more market share.
- To improve safety use the automotive practices of air
bags and restraining seated passengers.
- To improve security use the airlines' practices of identifying
passengers (ride cards) and closed circuit television cameras in stops.
- For the system to be quicker, there must be many stops
at or near where people want to go, sufficient vehicles waiting in the
stops (rather than people waiting for vehicles) non-stop guideways to the
destination, and higher average speeds than the alternate modes of transportation.
- First the planners find out where people want to go,
then plan stops near those places, then lay out a grid of guideways to
connect those places.
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This page last updated June 1, 2003