US city to pilot GPS-based traffic signal priority

One Arizona city plans to use GPS-based technology to move emergency vehicles more efficiently through traffic.

In an upcoming pilot, Tempe, part of the Phoenix metro region, will partner with digital transportation technology company LYT to add GPS-based signal technology at 12 intersections. The new system will give emergency vehicles green lights as they approach the signal, Tempe Senior Civil Engineer Ellie Volosin said via email.

The one-year pilot will explore the feasibility of deploying the LYT system across Tempe; how well the GPS solution works in a “real world” setting; and whether response times are, in fact, improved, Volosin said. LYT announced the initiative in a news release March 19.

The city’s existing optical system, which uses a transmitter on the emergency vehicle to send a light signal to a receiver on the signal infrastructure, will not be disabled. Instead, the two systems will be compared and analysed.

The LYT system needs no additional hardware or infrastructure, and is expected to require less maintenance activity, Volosin said. The city of Fremont, California deployed the technology as part of a Smart Corridor initiative undertaken in 2022. It has helped make cross-town response times 62% quicker, LYT CEO Tim Menard said via email.

The LYT system uses “GPS locators currently installed on emergency vehicles,” Volosin said, pushing out a signal to the controller when an emergency vehicle is approaching, extending the range of engagement with the intersection: “The only requirement is that the signal maintain communication with the traffic management center.”

The pilot project will include “a high-volume freeway interchange, several high-volume arterial-arterial intersections, several lower volume arterial-collector intersections, and one signalised pedestrian crossing,” she said.

The Maricopa Association of Governments (MAG) and Northern Arizona University (NAU) are joining Tempe on the pilot project team; LYT is partnering with Transpo Group. The initiative will launch through MAG’s Emerging Technology Program. NAU will serve as an independent evaluator, funded separately by MAG’s Public University Task Force. – Government Technology/Tribune News Service