Many Washtenaw County residents know the University of Michigan (U-M) is studying connected and autonomous vehicle technology. But many likely don't realize that the largest real-world deployment of connected vehicle technology anywhere in the world is right in their backyard.
That deployment, the Ann Arbor Connected Vehicle Test Environment (AACVTE), involves about 2,500 vehicles equipped with technology that allows them to communicate with each other and with roadside infrastructure. About 2,000 of that total are personal vehicles, and another 500 come from commercial fleets.
One of the connected vehicles used in the Ann Arbor Connected Vehicle Test Environment.
The project involves 75 sites spread over 27 square miles around the city of Ann Arbor. The sites cover a wide range of traffic scenarios, including freeway exit and entrance ramps, two curve speed warning sites, and four pedestrian mid-block crossings. Roadside units at each site allows connected cars to communicate with the infrastructure in the area. The long-term vision is to create a future where traffic lights and other traditional infrastructure will no longer be necessary because cars can communicate with the world around them.
"Eventually, that should save money, because if it reduces crashes, that amounts to billions of dollars per year," says Debby Bezzina, AACVTE senior program manager. "It also improves fuel economy, and that way everyone is saving."
That efficient and safe future won't happen for "many years," Bezzina says, but when it does, it's likely to be a direct result of work being done in Ann Arbor today.
"We're collecting data every second"
The AACVTE started off in 2012 as the Safety Pilot Model Deployment, a $30 million joint project between the University of Michigan Transportation Research Institute (UMTRI) and the Michigan Department of Transportation (MDOT). The three-year project involved thousands of cars and 25 infrastructure sites. Bezzina says that project used older technology, and the current, expanded version of the project uses connected vehicle standards updated in 2016.
Scott Shogan, a connected and autonomous vehicle subject matter expert with engineering consulting firm WSP, also serves as infrastructure team leader for the AACVTE. He says the large number of vehicles equipped with connected technology sets the AACVTE apart from other connected vehicle projects.
Scott Shogan, AACVTE infrastructure team leader.
Shogan says many roadside units are deployed in other locations, but very few vehicles in those locations are equipped, and almost none are able to communicate with that infrastructure.
"Nobody else has had the length of experience the Ann Arbor deployment has had proving out the equipment," he says. "They've spent years in the field in all weather conditions."
A roadside unit at the intersection of Plymouth and Green roads in Ann Arbor.
The roadside units send information about motorist behavior and signal timing, such as how far from the stop bar a car is and how long they are waiting at a light, to a server at UMTRI, where it can be analyzed for patterns.
"We're collecting data every second of every day," Bezzina says.
Right now the project is in research mode and isn't implementing any changes based on its findings yet. But Bezzina says there is potential for improvements in signal timing and traffic flow.
The infrastructure of the future
City of Ann Arbor Public Service Area Administrator Craig Hupy says the city is always interested in experimenting with infrastructure and city operations, and it was on board with the project from early on. The city's priority is safety first, but efficiency and sustainability gains are also attractive.
"As we've gone on, we see the possibility of optimizing some of our (traffic) signal timing, potentially," Hupy says. "We're also expecting (to improve) safety with pedestrian crossings."
Hupy adds that the city is considering doing a project with the AACVTE to understand motorist behavior in roundabouts at some point in the future.
Collin Castle, ITS program manager with MDOT, says MDOT's main interest in the project is showing that the technology works and offers real safety benefits.
The next big challenge will be "standardizing the deployment of the technology in a consistent manner across jurisdictional boundaries," Castle says.
It's one thing for the technology to work seamlessly within the city of Ann Arbor, and another for an equipped car to accurately communicate with the infrastructure in another city or even another state.
Castle says standards have been established, but there's some room for interpretation, which can create ambiguity. For example, some connected technology might broadcast a location using exact GPS coordinates, or it might do so by communicating the location in terms of its distance from surrounding objects.
"When a vehicle rolls up that's configured via the standard, but (officials) haven't made that determination about a proper, consistent approach, that could be a challenge," Castle says.
Shogan says another hurdle will be determining the business model for deploying the technology. Public agencies are unlikely to deploy it with existing funds, he says, because there's already not enough money for existing transportation needs. A business model would need to support deployment while providing some benefits to whatever private partner is involved, he says.
"That could be data or services to help offset the cost of deployment," Shogan says. "That's a big piece of the puzzle. How do you see this moving forward from a funding standpoint? And what is the role for insurers? There are lots of questions that are difficult to answer that are not just on the technical side but the business side."
Though that business model might not be totally worked out, suppliers are already using the technology being studied at the AACVTE to develop commercial products today.
Bezzina says she is excited about the project and how it has put Michigan at the forefront of connected vehicle technology. She hopes that the technology will soon be deployed nationwide instead of just in pockets around the country.
"It was a long, hard road to get these devices to the level they are today and ready for production," she says. "But I'm happy that we have come a long way, and we're on the cusp of being able to save lives."