It could be 10 years before wireless road-trains become part of everyday driving but, the technology could be put to use in the near future.Wireless technology to links a road train, led by a truck was demonstrated at the conclusion of the Safe Road Trains for the Environment (SARTRE) project, in which Volvo Trucks participated.The EU-financed project recently presented the results of three years of research and trials to representatives from the EU Commission and experts in transport technology from Europe, the US and Japan.A fully functioning wireless road train was shown in operation at Volvo’s proving ground in Sweden.In the lead was a Volvo FH truck, followed by another Volvo truck and three cars.SELF-DRIVING CARSThe representatives saw that the project’s aims had been achieved: development of a technology for wireless road trains that can improve traffic safety, reduce the environmental impact of road traffic and improve traffic flow. The building of test vehicles, car-to-car communication and sensors to control nearby vehicles has been under way for three years.The entire road train is interconnected through wireless technology that keeps the trailing cars exactly in the track of the lead vehicle and allows their drivers to relax.Andreas Ekfjorden, project manager for Volvo Trucks’ portion of the SARTRE project, explained: “The gap between the vehicles is much smaller than in normal traffic but it is as safe, even safer, to be part of such a train as lightning-quick computers and not human beings respond to even the slightest change in the train.“Each vehicle has a roof-mounted antenna to receive information from the lead vehicle’s computer. For instance, if the lead truck starts braking,the other vehicles brake at exactly the same time."SAFER AND MORE ECONOMICALThe purpose of SARTRE – to increase safety and decrease fuel consumption – is why Volvo Trucks chose to participate in the project. It is the cars’ fuel consumption that drops the most as a result of the reduced air drag in the compact convoy but the lead truck’s fuel consumption is also cut.This, Volvo says, will make it profitable for haulage firms to provide lead trucks. Vehicles that join the convoy could pay a fee to the haulierLennart Pilskog, director public affairs at Volvo Trucks, said: “It’s fantastic that a truck can be driven from A to B with at least one car behind, cutting fuel consumption and carbon dioxide emissions. FUTURE CHALLENGES REMAINHowever, although the SARTRE project has developed well-functioning road-train prototypes, there are still challenges before the system can become an everyday reality. For instance, reliability must be on par with that of an aircraft’s autopilot before road trains can emerge as a truly viable transport solution.Another challenge is the transition from convoy to manual control and vice-versa. Legislation is yet another vital issue: the Vienna Convention makes it illegal not to have control of one’s vehicle; in short, automated driving is not allowed. Adapting the convention and various EU countries' national legislation could take at least 10 years.Pilskog added: “Despite legislative challenges, there are so many benefits to be derived from road trains – in terms of traffic flow, safety, the environment and not least haulage firm profit – that I believe this will become a reality in one form or another."While it may take time for wireless road-trains to become a reality applying the technology in other areas could put research results into use in the near future. Wireless comms could be used by cars and trucks to, for instance, warn of collisions, obstacles or road ice.Pilskog said: "A lot like being able to look around a corner... it’ll be a major help in improving road safety."