Improving Dynamic Travel Time Estimates for Melbourne’s Drive Time System

Abstract

Vic Roads Drive Time is an operational ITS system that dynamically calculates travel times on Melbourne freeways and conveys them to motorists in real time on roadside Changeable Message Signs. While the system has gained acceptance from users, it has a tendency to predict low and high travel times in the lead up to and decline from peak periods respectively. This paper presents a new algorithm for predicting freeway travel times based on work commissioned by Vic Roads. The new algorithm has the ability to be used in any traffic situation between any two points. It also has the ability to account for the relative speeds and densities of vehicles within the traffic stream. Calibration and field testing of the enhanced algorithm has indicated that substantial improvements in travel time prediction can be achieved when compared to the existing system.