As declines go, Detroit’s has been spectacular. So it’s a little strange to discover—just a short drive north of downtown, past countless deserted office blocks and homes—something that could help make cities safer, more energy-efficient, and generally more pleasant to live in. In Warren, Michigan, General Motors is testing technology that lets cars transmit and receive useful information wirelessly across several hundred meters.
Well before fully automated vehicles like Google’s self-driving car hit the roads, so-called vehicle-to-vehicle communications should improve road safety by warning drivers of an impending collision or alerting them to treacherous road conditions ahead. The technology should also complement greater vehicle automation, providing a clearer picture of surroundings than onboard sensors alone and letting automated vehicles coördinate their actions. Eventually, connected vehicles should also benefit cities, acting as mobile sensors within vital transportation arteries and helping prevent accidents, control congestion, and reduce energy use.
Over time, the information gathered from connected cars could even reveal urban patterns to guide policy makers and planners. City planners armed with huge amounts of traffic-flow data could more easily identify problem intersections, for instance, or pinpoint the ideal spot for a new bus stop.
Before cities can realize the benefits of connected vehicles, however, the technology required to network cars wirelessly needs to be worked out. And at its R&D facility in Warren, GM is testing what’s likely to be the first generation of car-to-car communications.
Hariharan Krishnan, a GM technical fellow, took me for a spin around campus in a luxurious but otherwise normal-looking Cadillac. As we approached an intersection, one of Krishnan’s colleagues accelerated toward us from the left in another car. The second vehicle was obscured from view by an inconveniently located bush, but a few seconds before impact, red lights flashed on the Cadillac’s dashboard, the front seats buzzed a warning, and Krishnan hit the brakes. While some high-end cars are already equipped with automated braking systems that rely on cameras, radar, or other sensors, GM’s wireless system has a longer range, and it can see hazards around corners or behind obstructions. “You can see that I was completely blinded,” Krishnan said as the other car flew by. “The technology is uniquely positioned to help in these blind-side collisions.”
Both cars were equipped with wireless transmitters and receivers that relay position, speed, direction of travel, and other information to nearby vehicles 10 times per second. The equipment uses a frequency allocated in part for car-to-car communications by the Federal Communications Commission, and all data is encrypted. A computer stashed in the trunk of our vehicle recognized an impending collision and automatically sounded the alarm. The setup could help in other situations—preventing rear-endings, for example, by warning that a car ahead has hit the brakes. It might also warn of ice on the road ahead, based on other vehicles’ braking information.
Earlier this year the University of Michigan’s Transportation Research Institute concluded a two-year, government-funded project called the Safety Pilot Study that collected data from nearly 3,000 vehicles fitted with wireless communications equipment. The results suggested that wireless communications could prevent more than 500,000 accidents and 1,000 deaths each year on U.S. roads, and the National Highway Traffic Safety Administration announced in August that it would begin drawing up rules to mandate the technology in new vehicles.
Some car companies are a step ahead. In September, GM announced that in 2017 it will begin selling the first car in the U.S. equipped with car-to-car communication as a safety feature.
The opportunities for connecting these vehicles to city infrastructure can be found a 45-minute drive west of Detroit, in the city of Ann Arbor, where researchers from the University of Michigan are experimenting with transmitters added to roadsides and built into infrastructure such as traffic lights. At one point during a demo, the display warned the driver that he was approaching a sharp curve too quickly; at another it showed when the traffic light ahead was about to change.
The real benefits of these systems will come if cities use this data to guide decisions about traffic management and long-term planning. And for many, connecting vehicles and infrastructure will create a vastly more intelligent traffic system.
But car-to-car communication could prove tricky for cities. The addition of such technology to city infrastructure is unlikely to be mandated, leaving it up to local governments to decide whether they can afford the cost.
Alexei Pozdnoukhov, director of the Smart Cities Research Center at the University of California, Berkeley, says that in the end, it might be more cost-effective for cities to try to use smartphones to track drivers’ movements.