Enhanced vehicle detection at traffic signals and on smart freeways

The purpose of this project is to investigate alternative vehicle detection technologies for traffic signal control and smart freeway operations through a comparative desktop analysis and field trials of shortlisted technologies at two locations (intersection and freeway).

This research will be used to inform decisions on future traffic network investments, primarily through the future enhanced detection installation business case and delivery strategy, particularly for future smart freeway projects.

Participants

• • University of Western Australia
  • Main Roads Western Australia

Project background

1. Overall policy need

Traffic signal operations currently use stop line vehicle detection via loop, timers and pedestrian push button detection. This gives a limited understanding of vehicle behaviour and queues at an intersection. Enhanced detection of queuing, pedestrian movements, turn pocket capacity, shared lane use and selective vehicle (e.g. freight, buses, emergency vehicles) could enable improved traffic signal operation and more efficient vehicle movements.

Roads and Maritime Services, now part of Transport for NSW, are currently trialling an update to the SCATS system (traffic signal control system) to effectively utilise loop data from strategic loops installed at mid-block and turn pocket locations. Main Roads Western Australia want to understand the most appropriate detection technology to use when this SCATS update is available.

Traffic signal vehicle detection is currently achieved through inductive loops within the road surface. These loops are effective detectors, however, they are relatively costly and intrusive to install and maintain. Main Roads Western Australia will be installing enhanced detection at existing intersections where underground boring may be difficult to achieve due to existing services.

There is also a limitation on loop feeder cable length which may limit the potential enhanced detection locations. Alternative vehicle detection technologies that are compatible with the new SCATS detector algorithms should be investigated. Consultation may be required to ensure alternative technologies are compatible with SCATS and the existing traffic signal controllers.

Additionally, there is a need to have a formal assessment done on the different vehicle detection system (VDS) technology available to determine which provide the most operational benefit when contributing to smart freeways functionalities (coordinated ramp signals and variable speed limits).

There is also a need to have a formal assessment done on the different vehicle detection system (VDS) technology available to determine which provide the most operational benefit when contributing to Smart Freeways functionalities (Coordinated Ramp Signals and Variable Speed Limits).

2. Future traffic network investments

This project is essential to inform decision making on future traffic network investments. This project is timely as it enables field trials of the most promising vehicle detection technologies for next generation traffic signal intersections and smart freeways.

The expected technical contributions are:

• Survey of available above/below-ground vehicle detection technologies for traffic signal control and smart freeway operations.
• Evaluation of field operating performance of selected vehicle detection technologies for traffic signal control and smart freeway operations. More specifically, we will investigate how the various identified technologies would perform individually and in combination.
• Provide advice on how to best position the various vehicle detectors to achieve improved coverage and performance for different traffic conditions.
• Temporal aspect – determine whether a real time component is required.

Project objectives

To investigate alternative vehicle detection technologies for traffic signal control and smart freeway operations through a comparative desktop analysis and field trials of shortlisted technologies at two locations (intersection and freeway) in order to inform the future enhanced detection installation business case and delivery strategy.

This project will:

• Identify most appropriate vehicle detection technologies to be tested in trials
• Provide advice in the form of a recommendation report on how to best position the various vehicle detectors to achieve improved coverage and performance for different traffic conditions
• Assess performance of vehicle detection technologies for traffic signal intersection
• Assess performance of vehicle detection technologies for Smart Freeways

Please note …

Ongoing, this page will be a living record of this project. As it continues, matures, hits milestones, etc., we’ll add information, links, images, interviews and more. Watch this space!