European motorists need not worry if they see a driver that's not paying attention to the road while tailgating another car – it's all in the name of science. A project to link cars headed in the same direction into semi-autonomous "road trains" is moving from concept to reality.

We first told you about road trains last year when the European Union's Safe Road Trains for the Environment (EU Sartre) initiative began. In a road train, a platoon of cars are electronically tethered to follow closely behind a professionally driven lead vehicle – most likely a bus. While the cars can drive themselves on highways, this Sartre does have an exit and drivers can take over the wheel whenever it's time to head to an individual destination.

With the system, Sartre engineers hope to increase aerodynamic efficiency and reduce congestion with no changes in infrastructure, while giving drivers all the benefits of carpooling with the privacy of an individual car.

After a year of concept development and simulation work, which can be seen in the video below, Sartre plans to have a real-world test with a single following car by the end of 2010. The prospect of keeping our eyes on our iPads while our cars drive themselves in formation behind a lead vehicle seemed intriguing, so we were glad to hear that the tests seemed to be going well.

"We now look forward to the next stage of the work of the project, which will see vehicle tests, initially of just of a single vehicle for sensor, actuator and control-system validation," said Tom Robinson, project coordinator for Ricardo U.K., one of Sartre's seven project partners. "Then of a two-vehicle platoon later this year and subsequently through the remainder of the project, a multiple-vehicle platoon in order to test, develop, validate and identify remaining implementation issues for the entire Sartre system."

Development will continue until 2012, with a five-car road train as a final project goal.

Image: EU Sartre

Video: Volvo, one of seven partners in Sartre.

https://www.youtube.com/watch?v=KX46uhpAQaw