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Grouping vehicles into '''platoons''' is a method of increasing the capacity of roads. An automated highway system is a proposed technology for doing this.<ref>{{citation |title=The Aerodynamic Performance of Platoons |author=Zabat, Stabile, Frascaroll, Browand |ISSN=1055-1425 |url=http://www.path.berkeley.edu/PATH/Research/Featured/0199/}}</ref> | Grouping vehicles into '''platoons''' is a method of increasing the capacity of roads. An automated highway system is a proposed technology for doing this.<ref>{{citation |title=The Aerodynamic Performance of Platoons |author=Zabat, Stabile, Frascaroll, Browand |ISSN=1055-1425 |url=http://www.path.berkeley.edu/PATH/Research/Featured/0199/}}</ref> | ||
Platoons decrease the distances between cars using electronic, and possibly mechanical, coupling. This capability would allow many ]s 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 up to a fivefold increase in traffic throughput |
Platoons decrease the distances between cars using electronic, and possibly mechanical, coupling. This capability would allow many ]s to accelerate or brake simultaneously. Instead of waiting after a ] changes to green for drivers ahead to react, a synchronized platoon would move as one, allowing up to a fivefold increase in traffic throughput if spacing is diminished that much. This system also allows for a closer ] between vehicles by eliminating ] needed for human reaction. | ||
Platoon capability might require buying new cars, or it may be something that can be retrofitted. Drivers would probably need a special license endorsement on account of the new skills required and the added responsibility when driving in the lead. | Platoon capability might require buying new cars, or it may be something that can be retrofitted. Drivers would probably need a special license endorsement on account of the new skills required and the added responsibility when driving in the lead. | ||
]s with ] could automatically join and leave platoons. The |
]s with ] could automatically join and leave platoons. The automated highway system is a proposal for one such system, where cars organise themselves into platoons of eight to twenty-five. | ||
== Potential benefits == | == Potential benefits == | ||
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=== How it works === | === How it works === | ||
In one scheme, the roadway has magnetized stainless-steel spikes driven one meter apart in its center{{Fact|date=October 2007}}. The car senses the spikes to measure its speed and locate the center of the ]. Furthermore, the spikes can have either magnetic north or magnetic south facing up. The roadway thus |
In one scheme, the roadway has magnetized stainless-steel spikes driven one meter apart in its center{{Fact|date=October 2007}}. The car senses the spikes to measure its speed and locate the center of the ]. Furthermore, the spikes can have either magnetic north or magnetic south facing up. The roadway thus provides small amounts of digital data describing interchanges, recommended speeds, etc. | ||
The cars have ] and automatic speed controls, which are controlled by a computer. | The cars have ] and automatic speed controls, which are controlled by a computer. |
Revision as of 21:37, 24 December 2010
Grouping vehicles into platoons is a method of increasing the capacity of roads. An automated highway system is a proposed technology for doing this.
Platoons decrease the distances between cars using electronic, and possibly mechanical, coupling. This capability would allow many cars to accelerate or brake simultaneously. Instead of waiting after a traffic light changes to green for drivers ahead to react, a synchronized platoon would move as one, allowing up to a fivefold increase in traffic throughput if spacing is diminished that much. This system also allows for a closer headway between vehicles by eliminating reacting distance needed for human reaction.
Platoon capability might require buying new cars, or it may be something that can be retrofitted. Drivers would probably need a special license endorsement on account of the new skills required and the added responsibility when driving in the lead.
Smart cars with artificial intelligence could automatically join and leave platoons. The automated highway system is a proposal for one such system, where cars organise themselves into platoons of eight to twenty-five.
Potential benefits
- Greater fuel economy due to reduced air resistance.
- Reduced congestion
- Substantially shorter commutes during peak periods.
- On longer highway trips, vehicles could be mostly unattended whilst in following mode.
Potential downsides
- Drivers would feel less in control of their own driving, being at the hands of computer software, or the lead driver
Automated highway system
An automated highway system (AHS) or Smart Road is a proposed intelligent transportation system technology designed to provide for driverless cars on specific rights-of-way. It is most often touted as a means of traffic congestion relief, as it would drastically reduce following distances and headway, thus allowing more cars to occupy a given stretch of road.
How it works
In one scheme, the roadway has magnetized stainless-steel spikes driven one meter apart in its center. The car senses the spikes to measure its speed and locate the center of the lane. Furthermore, the spikes can have either magnetic north or magnetic south facing up. The roadway thus provides small amounts of digital data describing interchanges, recommended speeds, etc.
The cars have power steering and automatic speed controls, which are controlled by a computer.
The cars organize themselves into platoons of eight to twenty-five cars. The platoons drive themselves a meter apart, so that air resistance is minimized. The distance between platoons is the conventional braking distance. If anything goes wrong, the maximum number of harmed cars should be one platoon.
Early development
The origin of research on AHS was done by a team from The Ohio State University led by Dr. Robert E. Fenton. Their first automated vehicle was built in 1962, and is believed to be the first land vehicle to contain a computer. Steering, braking and speed were controlled through the onboard electronics, which filled the trunk, back seat and most of the front of the passenger side of the car. Research continued at OSU until federal funding was cut in the early 1980s.
Deployments
The PATH project, a prototype automated highway system, was tested in San Diego County, California in 1991 along Interstate 15. However, despite the technical success of the program, investment has moved more toward autonomous intelligent vehicles rather than building specialized infrastructure. The AHS system places sensory technology in cars that can read passive road markings, and use radar and inter-car communications to make the cars organize themselves without the intervention of drivers. Such an autonomous cruise control system is being developed by Mercedes-Benz, BMW, Volkswagen and Toyota.
See also
References
- Zabat, Stabile, Frascaroll, Browand, The Aerodynamic Performance of Platoons, ISSN 1055-1425
{{citation}}
: CS1 maint: multiple names: authors list (link) - http://www.memagazine.org/backissues/membersonly/may98/features/smarter/smarter.html
External links
- Roadtrains.US
- Vehicle Platooning and Automated Highways Description of the San Diego experiment.
- Underground Automated Highway Systems Forecast for the future of urban transportation.
- Safe Road Trains for the Enivironment