Accessing the potential of short term prediction in a dynamic route guidance system by evaluating its floating car data.

The ITF Intertraffic and Siemens consortium started operating a Dynamic Route Guidance (DRG) system with the Euro Scout technology in Berlin from February 1996, as a field test with 650 equipped vehicles. The system uses historic travel time profiles to calculate route recommendations that are updated every 11 to 12 minutes. The equipped vehicles send back data that amount to c. 60,000 travel time values covering up to 600 hours and 17,000 km per working day. Nevertheless the fleet is too small to activate the system's short term travel time prediction. Results have shown overall average travel time savings in the range from 2 to 4% for the whole network in any normal traffic situation - with nearly "unlimited" outbreaks to higher savings depending on the severity of incidents causing delays.