Traffic information services have evolved from delivering basic guidance to users (such as the location of specific incidents or major congestion) to offering real-time traffic flow data and now to helping drivers make better decisions by providing real time and predictive information.
As car drivers we don’t like everyday traffic congestion, but we become used to it and plan for it. We leave early enough to get to where we are going on time. But unexpected congestion is another thing. We hate it. As you approach a traffic jam that you were not aware of (and its too late to do anything about it!) – this is the first level of traffic information.
There is a significant body research that confirms that unexpected delays are perceived differently from recurring delays due to peak period congestion. Studies have found that transport users placed a value on travel time variability of more than twice the value placed on the average travel time. So maybe drivers will pay to not be surprised. Travellers want travel time reliability – or they want good traffic information in real-time to help them decide how to avoid traffic jams.
Traffic information is becoming readily available as decision support in congested conditions. The first generation of traffic information involves a basic level such as recorded messages on traffic hotlines, radio broadcasts, text descriptions on websites or SMS messages to your phone.
The next generation involved graphic displays of congestion levels (usually traffic speeds). A number of free traffic services have also sprung up, many by transport agencies and some as an adjunct to search engines (and advertising). Google provides live traffic information for many large US cities on Google maps (maps.google.com).
Similar services are available around the world, such as provided on the Traffic England site by the UK Highways Agency (www.trafficengland.com), VMZ in Berlin (www.vmz-info.de) and One Motoring site by Singapore’s Land Transport Authority (www.onemotoring.com.sg). In Australia the Royal Automobile Club of Victoria provides a free site (www.racv.com.au) with current congestion levels. This information is provided by Suna Traffic Channel (more about them later).
Melbourne current congestion levels Source: http://www.racv.com.au
These services provide useful information to plan your journey and avoid unexpected delays, however they need to be viewed in a browser on your computer, and conditions may well change by the time you have travelled part the way on your journey. Availability of the latest generation smart phones overcomes this, as you can now take the information with you (but may not be very safe to view while driving).
These solutions can give drivers a rough idea of what traffic is like right now, or plot the shortest route to a destination based on speed limits. However data from traffic detectors can be incomplete and services don’t take adequate account of other dynamic variables that can affect traffic patterns, like sporting events, roadworks and weather.
In-vehicle information is the next obvious development. Services packaged with in-vehicle navigation devices have been available for some time (outside of Australia). In late 2007 the Suna Traffic Channel (http://www.sunatraffic.com.au) was established as a subscription service, now available in Melbourne, Sydney and Brisbane through various in-vehicle navigation devices equipped with a RDS-TMC (Radio Data Message – Traffic Message Channel) receiver. This service can either inform the user of any delays on their route by a graphic on a map or a spoken message or automatically re-route around any significant traffic congestion. Suna’s service broadcasts traffic information, such as incidents and delays, as well as major events and other factors that may be of interest to motorists on motorways and other major traffic arterials.
The next generation of development is predicting congestion. INRIX (www.inrix.com), using modelling and prediction technologies, takes traffic information to a new level, helping drivers in major cities in the US and UK make better decisions through real time, historical and predictive traffic data generated from a wide range of sources. Their Smart Dust Network collects real-time and historical data from hundreds of public and private sources – including anonymous, real-time GPS probe data from commercial, delivery and taxi vehicles, toll tags and road occupancy and speed from transport agencies, plus construction and road closures, events, school schedules and weather forecasts. Then using sophisticated Bayesian modeling and error correction technology generate accurate real-time and predictive traffic data (5 minutes, 15 days or 15 months into the future).
So where next?
Intelligent vehicles using advanced communications networks, such as Dedicated Short Range Communications (DSRC), could inform drivers about congestion ahead, provide information that warns drivers of changing traffic patterns, automatically adjust the timing on traffic signals along the route to smooth flows and suggest an alternate less congested route. This is the intention of the growing international trend to dedicate the DSRC 5.9 GHz radio frequency exclusively for traffic and safety applications. This could mean a new level of sophistication of supporting driver’s decision making to avoid congestion, maybe even a level of automation by your vehicle.