Knowledge of the relationship between road conditions and driver behaviour is often insufficient. Major factors influencing a driver's operation of a vehicle include visual and kinaesthetic information about the friction conditions of the road surface. Low friction is an especially obvious problem under winter conditions. This project attempted to (1) answer the question of whether the simulator environment is sufficiently realistic for experiments with varying road conditions; and (2) clarify the importance of visual and kinaesthetic information for the driver. The experiment was designed around six scenarios: a road in summer condition, and five in winter conditions with different states of friction. The results demonstrated that driver behaviour in the simulator was realistic. Regarding speed and lateral position the behaviour was very consistent; there were always significant differences in speed levels between the summer scenario and all of the winter scenarios. There were no significant differences in the lateral positions. The conclusions are that visual information is by far the most important for the choice of speed, and that the drivers are very poor at evaluating different friction conditions. (A) For the covering abstract of the PIARC International Winter Road Congress, Luleå, Sweden, March 16-19, 1998, see ITRD no E202707.
Abstract