Technology: Getting Their Trucks in a Row, Europeans Revisit the Convoy

Researchers in Europe are working on a concept that will be familiar to anyone who has seen films about the bands of travelers who settled the American West. The project is developing an electronic communications system that enables a wagon train of tractor-trailer trucks and cars to make semiautonomous road trips possible — without the complexity of efforts like Google’s driverless vehicles.

The Volvos — both the car and truck companies, that is, which have different owners — call the idea “platooning” and see it as a bridge to traveling by driverless cars. It may look as simple as a pack of Nascar drivers strung together for a 200-mile-an-hour draft at Talladega, but this bridge is years away and faces challenges.

Rather than the increased speeds that are the incentive for nose-to-tail spacing on the racetrack, the goal of platooning is to reduce accidents caused by driver error.

Erik Coelingh, senior technical leader for safety and driver support technology at Volvo Car in Sweden, said in an interview that his group participated last year in successful tests involving a semitrailer that led another truck and three cars on European tracks and roads. The tests were part of a project called Safe Road Trains for the Environment, or Sartre, financed by the European Commission.

Drivers in vehicles outfitted with radar and laser systems that inform the adaptive cruise control, emergency braking and lane-departure systems, as well as video cameras, pulled in behind a moving semi. After getting the leader’s permission, the cars and truck linked wirelessly, and computers took over.

While the lead truck driver guided them, drivers in the following vehicles — each 12 feet apart — relinquished control. Alerts about emergency maneuvers were passed instantly through the platoon.

Fuel economy increased 10 percent to 20 percent, according to participants, because airflow behind a long, tapered shape creates less fuel-gobbling turbulence.

Asked about the system’s commercial viability, Mr. Coelingh did not mince words: “We’re not there yet.”

He said it could be a decade before platooning became a reality.

Volvo’s platoon research involves mostly technology that automakers already offer, as well as solutions expected in coming years,, including vehicle-to-vehicle computer communication. Installing that equipment in a new vehicle today, Mr. Coelingh said, would add about $5,300 to the sticker price. That includes redundant systems in case primary systems fail.

According to Mr. Coelingh, the project was started to answer questions about making driving safer. “But we’ve come up with a lot more questions,” he said.

Then there’s the interval between vehicles. Twelve feet might be too tight.

Volvo researchers found that at that distance, at highway speeds, even the computers couldn’t always read the lane markings needed to position vehicles. It also resulted in truck tires firing road grit into the radiator of the car behind the lead truck.

Intervals can be extended, but that cuts fuel savings, Mr. Coelingh said.