Estimation of static travel times in a dynamic route guidance system

In an Advanced Traveler Information System where route guidance is provided, a driver chooses a route before he/she actually traverses the links in the route. For such systems, link travel times need to be forecasted. However, information on several thousand links would take a fair amount of time to be conveyed to the driver, and very few drivers would be willing to wait very long to get route information, In the ADVANCE demonstration, to be implemented in suburban Chicago, the in-vehicle unit in each participating vehicle will be provided with the capability of accessing default travel time information, which will offer the vehicle with an autonomous navigation capability. The default estimates will be overwritten by dynamic up-to-the-minute forecasts if such forecasts are different from the default estimates. This paper describes the approach used to compute default travel times estimates.