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• Mobile data (wireless data communication using radio waves to send and
receive real time computer data).
• Wireless vehicle safety communications (electronic sub-system in vehicles
for the purpose of exchanging safety information about things like road
hazards, speed etc.).
• Emergency warning system for vehicles (matches warning information with
surrounding vehicles in the vicinity of travel).
• Intelligent vehicle technologies (includes self-contained autonomous electro-
mechanical sensors).
• Carsharing (allows an organisation to track its members’ usage and bill them
on a pay-as-you-go basis).
• Vehicle insurance (drivers’ behaviour ismonitored directly and this information
is transmitted to an insurance company).
1. Floating car data
Obtains travel time and speed data from vehicles travelling along the street by
using a triangulation method (from mobile phones), vehicle re-identification (detectors
mounted along the road) or GPS based methods. This technology provides advantages
like lower cost (compared to sensors or cameras), more coverage, faster set-up, less
maintenance and operation in all weather conditions. [8]
2. Sensing technologies
Sensing systems for ITS are vehicle-based and infrastructure-based networked
systems. Infrastructure sensors are indestructible devices that are installed or embedded in
the road or surrounding the road and may be manually disseminated during preventive
road construction maintenance or by sensor injection machinery for rapid deployment.
Vehicle sensing systems include deployment of infrastructure-to-vehicle and vehicle-to-
infrastructure electronic beacons for identification communication and may also employ
automatic number plate recognition or vehicle magnetic signature detection technologies.
Sensors can detect vehicles by inductive loops, video cameras, Bluetooth, audio
signal and information fusion from multiple traffic sensing modalities. [17]
3. Intelligent transport applications [13]
Among intelligent transport applications belong:
• Emergency vehicle notification systems (emergency call generated either
manually by the vehicle occupants or automatically via activation of in-
vehicle sensors after an accident).
• Automatic road enforcement (used to detect and identify vehicles disobeying
a speed limit or some other legal traffic requirement and automatically issue
a ticket to offenders based on the license plate number).
• Variable speed limits (variable speed limits that change with road congestion
and other factors).
• Collision avoidance systems (sensors notify objects ahead of the vehicle).
• Dynamic traffic light sequence.