A pair of trucks convoying 10 meters apart on Interstate 80 just outside Reno, Nevada, might seem like an unusual sight—not to mention unsafe. But the two trucks doing this a couple of weeks ago were actually demonstrating a system that could make trucking safer and much more efficient.
While the driver in front drove his truck normally, the truck behind him was partly operated by a computer—and it stuck to its leader like glue. When instructed to do so, the computer controlled the gas and brakes to pull to within 10 meters (roughly three car lengths) of the truck ahead. The computer then kept the two trucks paired at this precise distance, as if linked by some invisible cable, until the system was disengaged. If the truck in front stopped suddenly, the one behind could have reacted instantaneously to avoid a collision.
Most automobile companies are working on full vehicle automation, but they need to overcome significant challenges before they can deploy those technologies (see “Driverless Cars Are Further Away Than You Think”). The technology demonstrated in Nevada, in contrast, could be deployed today, since the system is only partially automated (the driver behind still steers, with the aid of a camera that shows the view ahead of the truck in front). So it is covered by the same guidelines and regulations as adaptive cruise control, a feature in some cars that automatically keeps vehicles on the highway a safe distance from the ones around them.
This kind of “platooning”—as it is known—reduces the wind drag on both trucks, and could therefore save trucking companies millions of dollars in fuel every year. The trucks were fitted with technology developed by a startup called Peloton Tech (“peloton” is the French word for platoon). Peloton’s system consists of radar sensors, a wireless communications system, and computers connected to each truck’s central computer. Video screens in both cabs show the drivers views of blind spots around the two vehicles.
Joshua Switkes, CEO of Peloton Tech, says the fuel savings are 4.5 percent for the front truck and 10 percent for the rear truck. This could amount to $100,000 each year. “For truck companies, these savings are enormous,” Switkes says. He adds that the technology could even allow competing companies to platoon together to get these savings.
Switkes says the technology should also improve safety, since drivers have greater visibility and the radar systems can brake automatically if needed. In theory, more trucks could be virtually tethered together this way, although the initial plan is to connect only two.
The prospect of two trucks driving so close together under computer control may raise concerns among other drivers, but the technology involved, including the vehicle-to-vehicle communications system used to share information between the two trucks, is set to become far more common in the next few years. The U.S. Department of Transportation has indicated that it plans to mandate such communications systems in new vehicles in the hopes of improving road safety (see “The Internet of Cars Is Approaching a Crossroads”).
Vehicle platooning has been a subject of research in industry and academia for decades, but efforts have intensified in recent years as the underlying technology has advanced.
A European project, called SARTRE (Safe Road Trains for the Environment), has been exploring ways for vehicles to travel in platoons since 2009. This effort is funded by the European Commission and involves various companies, including the carmaker Volvo. Another effort, called Energy ITS, which is backed by the Japanese government and involves several Japanese universities, has been testing platoons made of three semi-automated or fully automated trucks since 2007. A U.S. project, called PATH (Partners for Advanced Transportation Technology), operated out of the University of California, Berkeley, is testing vehicle platooning along with other technologies designed to improve transportation.
Steven Shladover, a research engineer at UC Berkeley involved with PATH, says that his own experiments indicate that platooning vehicles even closer together—just a few meters apart— could lead to fuel savings of 20 percent. But it would also introduce new risks. Once trains of trucks get too long, it’s much harder for drivers of other cars to change lanes. “I would not advocate running very long sequences of these trucks close together,” Shladover says.