EU-funded scientists have successfully demonstrated a road train technology that could boost road safety and driver comfort while cutting congestion and carbon emissions. In the system, the driver of the lead vehicle of a convoy controls the other vehicles, allowing their drivers to safely engage in other activities.

The technology is an outcome of the SARTRE ('Safe road trains for the environment') project, which is funded to the tune of EUR 3.8 million under the Transport Theme of the Seventh Framework Programme (FP7). The three-year project started in 2009 and its seven partners come from Germany, Spain, Sweden and the UK.

The platooning concept links vehicles driving along motorways in convoys. The lead vehicle is driven by an experienced driver who knows the route well, and could be a taxi, bus or lorry, for example. The lead vehicle controls the following vehicles' acceleration, braking and steering by wireless technology. As well as following virtual 'breadcrumbs' left by the lead vehicle, convoy vehicles also use sensors to track the car directly in front of them and adjust their distance, speed and direction accordingly.

When a vehicle wishes to join a convoy, the driver simply sends a request to the leader of the convoy. When the request is accepted, the convoy leader takes control of the vehicle, allowing the driver to sit back and relax, read a book, eat, drink, or use a computer or phone. When a driver wants to leave the convoy, he or she sends a signal to the leader to regain manual control of the vehicle and exit the convoy. The system automatically closes up the gap created.

The SARTRE technology tackles four major issues in the road transport sector: road safety, fuel consumption and carbon emissions, congestion, and driver comfort.