Dashboard phones track traffic light wait times
A network of dashboard smartphones that monitors traffic lights and congestion can tell drivers when to slow down to avoid idling, cutting fuel use by 20 percent, according to researchers at Princeton University and MIT.
SignalGuru (PDF) collates traffic data from images captured by dashboard smartphones.
It also graphically shows drivers how fast to go to avoid stopping at the next light; a commercial version would have audio suggestions. The system could also be developed to advise motorists to take a side street to avoid congestion ahead.
The researchers deployed iPhones on car dashboards in Cambridge, Mass., and in Singapore. In the former, where traffic signals with fixed schedules are used, SignalGuru could predict when lights would change with an error margin of two-thirds of a second. In Singapore, which has signals that adapt to traffic volume, the error increased to one second up to just over two seconds.