Driver's characteristic of distance identification on freeway at night

In order to ensure enough time for drivers on freeway to acquire information at night, it is necessary to study on driver's characteristic of distance identification at night. The quantitative impacts of driving speed, horizontal curve radius and longitudinal slope on driver's identification distance at daytime and nighttime were studied based on comparative analysis on driver's identification distance at daytime and nighttime under different condition of driving speed and highway alignment. The relation model was established between driver's identification distance at night and driving speed, horizontal radius, longitudinal slope. It indicates that there is negative linear, positive logarithm, negative exponential relation respectively between driver's identification distance and driving speed, horizontal curve radius, longitudinal slope at night.