Platoon (automobile)
Encyclopedia
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 car
s 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 car
s 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.
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.
. 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 platoon
s 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.
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.
The SARTRE Project (Safe Road Trains for the Environment
), is a European Commission funded project investigating implementation of platooning on unmodified European motorways. Begun in September 2009, the three year project successfully trialled a two vehicle platoon in January 2011.
Platoons decrease the distances between cars using electronic, and possibly mechanical, coupling. This capability would allow many car
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...
s to accelerate or brake simultaneously. Instead of waiting after a traffic light
Traffic light
Traffic lights, which may also be known as stoplights, traffic lamps, traffic signals, signal lights, robots or semaphore, are signalling devices positioned at road intersections, pedestrian crossings and other locations to control competing flows of traffic...
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
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...
between vehicles by eliminating reacting distance
Braking distance
Braking distance refers to the distance a vehicle will travel from the point where its brakes are fully applied to when it comes to a complete stop...
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 car
Smart car
Smart car may refer to:*Intelligent car, a car with artificial intelligence*Smart , the automobile brand...
s with artificial intelligence
Artificial intelligence
Artificial intelligence is the intelligence of machines and the branch of computer science that aims to create it. AI textbooks define the field as "the study and design of intelligent agents" where an intelligent agent is a system that perceives its environment and takes actions that maximize its...
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 economyFuel economy in automobilesFuel usage in automobiles refers to the fuel efficiency relationship between distance traveled by an automobile and the amount of fuel consumed....
due to reduced air resistance. - Reduced congestionTraffic congestionTraffic congestion is a condition on road networks that occurs as use increases, and is characterized by slower speeds, longer trip times, and increased vehicular queueing. The most common example is the physical use of roads by vehicles. When traffic demand is great enough that the interaction...
- Substantially shorter commutes during peak periods.
- On longer highway trips, vehicles could be mostly unattended whilst in following mode.
- Fewer traffic collisions
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 systemIntelligent transportation system
The term intelligent transportation systems refers to information and communication technology that improve transport outcomes such as transport safety, transport productivity, travel reliability, informed travel choices, social equity, environmental performance and network operation...
technology designed to provide for driverless cars
Driverless car
An autonomous car, also known as robotic or informally as driverless, is an autonomous vehicle capable of fulfilling the human transportation capabilities of a traditional car. As an autonomous vehicle, it is capable of sensing its environment and navigating on its own...
on specific rights-of-way. It is most often touted as a means of traffic congestion
Traffic congestion
Traffic congestion is a condition on road networks that occurs as use increases, and is characterized by slower speeds, longer trip times, and increased vehicular queueing. The most common example is the physical use of roads by vehicles. When traffic demand is great enough that the interaction...
relief, as it would drastically reduce following distances and 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...
, 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 laneLane
A lane is a part of the roadway within a road marked out for use by a single line of vehicles in such a way as to control and guide drivers for the purpose of reducing traffic conflicts. Most public roads have at least two lanes, one for traffic in each direction, separated by Lane markings...
. 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
Power steering
Power steering helps drivers steer vehicles by augmenting steering effort of the steering wheel.Hydraulic or electric actuators add controlled energy to the steering mechanism, so the driver needs to provide only modest effort regardless of conditions. Power steering helps considerably when a...
and automatic speed controls, which are controlled by a computer.
The cars organize themselves into platoon
Platoon (automobile)
Grouping vehicles into platoons is a method of increasing the capacity of roads. An automated highway system is a proposed technology for doing this....
s 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
Braking distance
Braking distance refers to the distance a vehicle will travel from the point where its brakes are fully applied to when it comes to a complete stop...
. 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 PATHPartners for Advanced Transit and Highways
California Partners for Advanced Transit and Highways is a collaboration between the California Department of Transportation , UC Berkeley, other public and private academic institutions, and private industry. PATH's mission: applying advanced technology to increase highway capacity and safety,...
project, a
prototype automated highway system, was tested in San Diego County, California
San Diego County, California
San Diego County is a large county located in the southwestern corner of the US state of California. Hence, San Diego County is also located in the southwestern corner of the 48 contiguous United States. Its county seat and largest city is San Diego. Its population was about 2,813,835 in the 2000...
in 1991 along Interstate 15
Interstate 15 in California
In the U.S. state of California, Interstate 15 is a major north–south route through the San Bernardino, Riverside, and San Diego Counties, and it has a length of in the state. It is a major thoroughfare for traffic between Southern California and Las Vegas, Nevada, as well as points beyond...
. 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
Autonomous cruise control system
Autonomous cruise control is an optional cruise control system for road vehicles. It makes no use of satellite or roadside infrastructures nor of any cooperative support from other vehicles. Hence control is imposed based on sensor information from on-board sensors only...
is being developed by Mercedes-Benz
Mercedes-Benz
Mercedes-Benz is a German manufacturer of automobiles, buses, coaches, and trucks. Mercedes-Benz is a division of its parent company, Daimler AG...
, BMW
BMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...
, Volkswagen
Volkswagen
Volkswagen is a German automobile manufacturer and is the original and biggest-selling marque of the Volkswagen Group, which now also owns the Audi, Bentley, Bugatti, Lamborghini, SEAT, and Škoda marques and the truck manufacturer Scania.Volkswagen means "people's car" in German, where it is...
and Toyota.
The SARTRE Project (Safe Road Trains for the Environment
Safe Road Trains for the Environment
Safe Road Trains for the Environment is a European Commission funded project to investigate and trial technologies and strategies for the safe platooning of road vehicles, a transportation concept in which several vehicles are electronically linked together in a 'road train', with only the lead...
), is a European Commission funded project investigating implementation of platooning on unmodified European motorways. Begun in September 2009, the three year project successfully trialled a two vehicle platoon in January 2011.
See also
- Driverless carDriverless carAn autonomous car, also known as robotic or informally as driverless, is an autonomous vehicle capable of fulfilling the human transportation capabilities of a traditional car. As an autonomous vehicle, it is capable of sensing its environment and navigating on its own...
- Future of the carFuture of the carPotential future car technologies include varied energy sources and materials, which are being developed in order to make automobiles more more energy efficient with and reduced regulated emissions...
- Green waveGreen waveA green wave is an intentionally induced phenomenon in which a series of traffic lights are coordinated to allow continuous traffic flow over several intersections in one main direction....
- Vehicle Infrastructure IntegrationVehicle infrastructure integrationVehicle Infrastructure Integration is an initiative fostering research and applications development for a series of technologies directly linking road vehicles to their physical surroundings, first and foremost in order to improve road safety...
- Virginia Smart RoadVirginia Smart RoadThe Virginia Smart Road, also known as simply the Smart Road or Smart Highway, is a short, limited access road in Montgomery County, Virginia used for the testing of pavement technologies and as a proving ground for new transportation technologies. The Smart Road is currently a stretch of road...
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