AI-enabled ‘Smart Signals’ arrive in St. Petersburg 

St. Petersburg is deploying cutting-edge traffic signal technology that increases safety, mitigates congestion and accommodates connected and automated vehicles.

The artificial intelligence (AI)-enhanced systems adapt to real-time traffic conditions and weather changes. City council members unanimously approved purchasing 15 of the systems Thursday.

A $1.16 million state grant, which the city must spend by Dec. 31, supports the West St. Petersburg Smart Signal Corridors project. Cheryl Stacks, transportation and parking manager, said three of the included intersections are “routinely listed” on the police department’s “Top 10 Dangerous Crash Intersections” report.

“The AI object detection is good and getting better – getting smarter as it learns,” Stacks said. “That’s particularly important for detection of elements like pedestrians.”

Officials will install 10 “smart signals” along 66th Street North, from 38th Avenue to Pasadena Avenue, and five on Tyrone Boulevard, from 5th Avenue to Park Street. Stack said those closely spaced intersections, and surrounding congestion, lead to significant traffic speed and volume variability.

The Florida Department of Transportation (FDOT) awarded the grant in March 2023 through its Technology Application Partnerships with Local Agencies Program. Recipients must complete projects on state roads.

Stacks said the city initiative would “fill a gap between other corridors” with similar technology. Pinellas County has implemented smart signals north of the project site.

“The city has spent the last year or so in discovery and communications with our peers to consider which roadside units are best for St. Pete,” Stacks said. “The roadside units we’re recommending have video detection embedded as a part of the device, which is really a key benefit for us.”

A map of the project area. Screengrab, city documents.

Adaptive controls will extend green signals in response to current traffic conditions. Stacks said roadside units, mandated by FDOT, will eventually allow vehicles to communicate with the system when approaching intersections.

Signal cameras provide AI-powered object detection with 99.5% accuracy at up to 720 feet, regardless of weather conditions. Transportation officials will receive live, high-definition video streams of each intersection.

“The project will allow us to put in a new video wall at the Traffic Management Center for better citywide monitoring of our signalized intersections,” Stacks said. “I think where the biggest benefit of this grant comes into play is the fiber (optics) and increased communications technology between the signals back to the Traffic Management Center.”

New signal controllers and cabinets comprise about 27% of the project cost. Officials will dedicate a third to video detection software and use the remainder to install fiber optic data lines, purchase a new video wall and other upgrades that will provide citywide benefits.

Stacks said 18-inch cabinet “risers” will help protect from localized flooding. System maintenance should reduce traffic disruptions and employee safety risks.

Councilmember Richie Floyd questioned when the city would see some of the equipment’s “fancier stuff.” Stacks noted that while the system is “really robust,” connected vehicle technology is typically limited to government fleets.

Audi has pioneered vehicle-to-infrastructure technology. Other automakers like BMW and Volkswagen are experimenting with the nascent systems that allow drivers to receive signal and traffic alerts.

Cellular vehicle-to-everything technology enables communication between motorists and pedestrians. Stacks said the city’s system could continue evolving into “something better.”

The Traffic Management Center’s new video wall will mirror the one used in the Emergency Operations Center (right). Screengrab, city documents.

The signals, known for reliability, would revert to traditional timers during a malfunction. FDOT will pay the city for ongoing maintenance, and Stacks said officials could negotiate an increase or reimbursement if needed.

Councilmember Lisset Hanewicz noted that residents often seek more efficient updates regarding flooded roads during storms. Stack said staff can observe any issues from the video wall rather than relying on eyewitnesses.

“I think that’s what drivers are really going to want to see,” Hanewicz said. “I feel like we’re fleeing from the analog era to the digital era with this.”

The roadside units also enable traffic preemption to prioritize approaching emergency vehicles. Stacks said city and county officials, in partnership with area first responders, are exploring where that aspect would provide the least disruption and most benefit.

Council Chair Copley Gerdes, who represents the project area, said traffic gets “messy” around the “conglomerate of lights” on Tyrone Boulevard. He eagerly awaits receiving emergency information on his dash rather than phone, “and that’s the kind of stuff that’s coming with this technology.”

“I think we’ve been spoiled with not a ton of traffic,” Gerdes added. “Now we have more traffic, and anything that can help, I’m all for.”

The city will complete construction by Dec. 31.