ITS to improve speed behaviour for truck drivers : short term effects of a speed support system.

Heavy vehicles constitute a serious problem in traffic accidents; the risk of being killed in an accident involving heavy vehicles is about 2-3 times greater than for accidents without heavy vehicles. There are many factors contributing to the seriousness of the problem and high speed is one of them, in Sweden about 70 percent of heavy vehicles are speeding. One way of reducing speeds of vehicles is by implementing Intelligent Speed Adaptation and even though the effect of these systems is well known for cars, little has been done on heavy trucks. This study aims at investigating how effective an ISA system is for heavy trucks, it further aims at studying if motivation and bonus schemes can help to sustain the positive effect compared to traditional ISA. The Intelligent Speed Adaptation system used in this study is based on a handheld computer with GPS and can give both visual and audible feedback when speeding. This paper reports on the short term effects when implementing an Intelligent Speed Adaptation system in trucks. The present study has shown that truck drivers opinion with regard to ISA-systems is very much in line with the view of car drivers. They are in favour of systems giving them information on speed and cautiously positive to be given feedback when speeding, but they do not like systems limiting the speed of the vehicle. A majority of the drivers, 58 percent do not believe that the feeling of being monitored will increase; however 34 percent do believe it will increase and 8 percent believes it will increase a lot. The study has further shown that the ISA system has a great potential to improve speed behaviour for truck drivers. The mean speed is decreased instantly when the system is activated and the effect can be seen for all road types even though it is more evident for the roads with lower speed limits such as 30, 50 and 70 km/h. The study has also shown that the effect of the system is short and that the drivers need further motivation to keep the speed limit. For the long term study of this system more emphasis will be given on the motivation and bonus schemes. (A). For thecovering abstract of the conference see E216632.