The city of Calgary, Alberta, has implemented a traffic monitoring system that can show drivers how long they may be stuck in tailbacks by analysing the Bluetooth signals their phones give off.
The Travel Time Information System uses 15 sensors placed along a route, in this case the Deerfoot Trail road, that track unique Bluetooth signals given off by nearby mobile phones, before sending their location data to the city’s traffic management centre for processing.
The management centre counts the number and location of unique Bluetooth signals, interpreted as the number of drivers in a given area and the speed at which they are moving, and uses this as a basis for calculating traffic density and speed. Projected journey times along that stretch of road are then relayed to seven road signs along the route, so motorists know exactly how long they’ll be snarled up in a tailback.
Gord Elenko, manager of Calgary’s road traffic division explained to Phsy.org: “Drivers will be able to make informed route planning choices in real time. We believe it will eventually help reduce congestion and decrease driver frustration.”
With mobile phones use so common, there’s plenty of scope for data to be misinterpreted or abused, so clever algorithms are employed to make the process accurate and secure. Data collected from pedestrians and other sources near the Deerfoot Trail road, but not actually on it, are filtered out. Also, only a device’s unique Bluetooth ID code and MAC address are collected and the information is encrypted during processing.
Although there are no facts or figures as yet to gauge how well the system, which operates between 6:30am and 6:30pm from Monday to Friday, works in practice, more Bluetooth detection systems will be added elsewhere in the country as funds become available, so the local authorities seem to have faith in it.
This isn’t the first system of its type. TomTom sat navs with the Traffic HD feature (which feature SIM card and mobile phone connectivity) count the number of other TomTom devices on your route to help determine traffic flow. BMW’s RTTI (real-time traffic information) system works in a similar fashion.
But what makes Calgary, Alberta’s Travel Time Information System unique is that you don’t a satnav, BMW or app to reap the benefits – even a mobile phone isn’t necessary (although if nobody travelled with a phone, or at least a Bluetooth-equipped car or hands free system, the system would be as useful as a chocolate teapot).
As congestion in cities becomes more of an issue, this system and others like it will no doubt become more prevalent.