FUEL CONSUMPTION REDUCTION EXPERIENCED BY TWO PROMOTE-CHAUFFEUR TRUCKS IN ELECTRONIC TOWBAR OPERATION

In this paper fuel consumption reduction of two heavy-duty trucks driving at close spacing is presented. Within the European project PROMOTE-CHAUFFEUR at DaimlerChrysler two heavy-duty semi-trailer trucks of type ACTROS have been equipped for automated vehicle following (Electronic Tow Bar). While the lead truck is driven manually, the trail truck is completely operated by a vehicle controller and follows the lead truck automatically. With this Electronic Tow Bar system, it is possible to drive safely at very close spacing from 6 to 16 m at all velocities without any mechanical coupling. The experiments were carried out on the DaimlerChrysler test track at Papenburg with constant velocities. Under these nearly ideal conditions, the influence of drag reduction on fuel consumption could be directly investigated. As expected from the simulation, both trucks showed a considerable fuel consumption reduction in the experimental tests compared to drives in isolation. At a velocity of 80km/h and a spacing of 10 m, the measured fuel consumption reduction was about 21 percent for the trail truck which had a total weight of 28 t. With a total weight of 40 t, it is expected to be about 17 percent. Not only the trail truck but also the lead truck, which had a total weight of 14.5 t, experienced a fuel consumption reduction. For the lead truck a reduction of about 6 percent was measured at a spacing of 10 m. To verify and extend these results for normal traffic conditions, further experiments on public highways and with different loads are necessary. For the covering abstract see ITRD E114174.