Cars that communicate with each other could reduce fatal accidents on US roads

The secret to avoiding red lights during rush hour in Utah's largest city might be simple: follow a bus.

In recent years, transportation officials have refined a system in which radio transmitters on commuter buses communicate directly with traffic lights in the Salt Lake City area and request a few extra seconds of green as they approach.

Traffic jams on these so-called smart streets are already noticeably less crowded, but this is just a small preview of the high-tech upgrades that could soon be introduced on Utah's streets and, ultimately, across the United States.

Backed by a $20 million federal grant and an ambitious goal to “connect the West,” the goal is to eventually enable all vehicles in Utah and neighboring states of Colorado and Wyoming to communicate with each other and with road infrastructure to detect congestion, accidents, road hazards and weather conditions.

With this knowledge, drivers can immediately recognize that they should take a different route, eliminating the need for a human to manually send an alert to an electronic road sign or the mapping apps on mobile phones.

“A vehicle can tell us a lot about what's happening on the road,” says Blaine Leonard, a traffic engineering engineer with the Utah Department of Transportation. “Perhaps it braked hard, the windshield wipers are on, or the wheels are slipping. The car sends us this data anonymously ten times a second, providing us with a constant stream of information.”

When cars communicate information in real time to other cars and to the various sensors along and above the road, the technology is commonly known as Vehicle-to-Everything, or V2X. Last month, the U.S. Department of Transportation unveiled a national plan for how state and local agencies and private companies should implement the various V2X projects already underway to ensure everyone is on the same page.

The overarching goal is universal: to drastically reduce the number of deaths and serious injuries in road traffic, which has recently reached historic levels.

A 2016 analysis by the National Highway Traffic Safety Administration concluded that V2X could help. Nationwide implementation of just two of the first vehicle-to-everything applications could prevent 439,000 to 615,000 crashes and save 987 to 1,366 lives, the study found.

Dan Langenkamp has been advocating for safer roads since his wife Sarah Langenkamp, ​​​​a U.S. diplomat, was killed by a truck while cycling in Maryland in 2022. He joined officials at the press conference unveiling the Vehicle-to-Everything plan and urged governments across the U.S. to roll out the technology as widely and quickly as possible.

“How can we as government officials, as manufacturers and just as Americans not move this technology forward as quickly as we can, knowing that we have the power to rescue ourselves from this disaster, this crisis on our streets,” he said.

The biggest public opposition is directed against data privacy. Although the V2X rollout plan includes the protection of personal data, some privacy activists remain skeptical.

Critics say that while the system cannot track specific vehicles, it can collect enough identifying characteristics – even seemingly innocuous things like tire pressure – that it would not take too much effort to figure out who is behind the wheel and where they are going.

“If you have enough clear information, you can reasonably assume that the car in that weight class driving down that street at that moment probably belongs to the mayor,” said Cliff Braun, deputy director for technology, policy and research at the Electronic Frontier Foundation, which advocates for digital privacy.

The federal government's plan states that the country's 75 largest metropolitan areas should equip at least 25% of their traffic signal intersections with the technology by 2028, with even higher goals to be reached in the years after that. Thanks to the quick start, the Salt Lake City region has already exceeded the 20% mark.

Of course, upgrading the signals is the relatively easy part. The most important data comes from the cars themselves. While most new models have connected features, they don't all work the same.

Before embarking on the Connect the West plan, Utah officials tested the nation's first radio-based connected vehicle technology, using data exclusively from fleet vehicles such as buses and snow plows. An early pilot program improved bus routing on a busy stretch of Redwood Road, and bus drivers weren't the only ones noticing a difference.

“Whatever they're doing, it's working,” says Jenny Duenas, deputy director of nearby Panda Child Care, which houses 80 children between the ages of 6 weeks and 12. “We've had no traffic for some time now. We need to get our children out of here, and when it's much more free here, it's much easier to get out of the daycare.”

Casey Brock, bus communications manager for the Utah Transit Authority, said most of the changes might not be noticeable to drivers, but even shortening the bus route by a few seconds could dramatically reduce congestion while improving safety, he said.

“From a commuter's perspective, it might be, 'Oh, I had a good day with a lot of traffic,'” Brock said. “You don't need to know all the mechanics that go on behind the scenes.”

This summer, Michigan opened a 3-mile stretch of a connected and automated vehicle corridor on Interstate 94 between Ann Arbor and Detroit. The pilot project includes digital infrastructure, including sensors and cameras installed on poles along the highway that help drivers prepare for traffic delays by sending alerts about things like debris and stranded vehicles.

Similar technology is being used in an intelligent freight corridor around Austin, Texas, which will inform truck drivers about road conditions and eventually enable connection to self-driving trucks.

Darran Anderson, director of strategy and innovation at the Texas Department of Transportation, said officials hope the technology will not only boost the state's huge freight industry but also help reverse a troubling trend that has persisted for more than two decades. The last day without a traffic fatality in Texas was Nov. 7, 2000.

Cavnue, a Washington, D.C.-based subsidiary of Alphabet's Sidewalk Infrastructure Partners, funded the Michigan project and won the contract to develop the Texas project. The company aims to become an industry leader in smart roads technology.

Chris Armstrong, vice president of product at Cavnue, calls V2X a “digital seatbelt for the car,” but says it will only work if cars and road infrastructure can communicate seamlessly with each other.

“Instead of speaking 50 different languages, we would like to all speak the same language overnight,” he said.