To optimise road maintenance and operation, road administrators are increasingly using management systems. An important requirement of such systems is the assessment of how different road conditions and measures of maintenance and operation effect road users. 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 kinesthetic information about the friction conditions of the road surface. Low friction is an especially obvious problem under winter conditions. This project attempted to answer the question of whether the driving simulator environment is sufficiently realistic for experiments with varying road conditions, and clarify the importance of visual and kinesthetic 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 result 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, and no significant differences between 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 drivers are very poor at evaluating different friction conditions. (A)
Abstract