Transport and Main Roads, Queensland Government

Project title: Transport Mode and Cluster Separation in Road Traffic Network Travel Times

Project partner: Queensland Government – Department of Transport and Main Roads

Brief outline:

Travel time data of traffic is currently collected on links across South East Queensland. Individual data with location and timestamp is captured at over 300 nodes across the road network and links are created between these nodes. Matching between the nodes is performed to create an average travel time based on the time difference at each node.

Currently the system produces a single travel time with data filtered using the Median Absolute Deviation (MAD) method to remove outliers from the calculation of travel time. This methodology gives a simple result, however, it does not explicitly identify the multiple vehicle modes (cars, buses, bicyclists, pedestrians) from which the data is collected. Furthermore, effects such as data clustering (multiple captures for high occupancy vehicles) are not accounted for. Issues such as these could skew the travel time and yield a result that is not representative of any particular vehicle mode.

The focus of this project will be to try and identify multiple vehicle modes and clusters within the data with a view to producing an algorithm for calculating multiple travel times across the same network link. It is hoped that such information can then be used to calculate more representative travel times for the various vehicle modes that utilise the entire network.