Speed Control and Driver Psychophysiology Performance in Highway Uphill Sections

Many accidents occurred in highway uphill sections. Changes in the vehicle speed may cause accidents. The driver’s psychological state is closely related to the control of speed. In this paper, 16 participants were selected for a field driving experiment, where the speed change data of a single vehicle traveling in highway uphill sections and the corresponding participants’ physiological performance data during the experiment were all collected. Then the instantaneous speed, eye movement parameters, and heart rate (HR) of each participant were analyzed with statistical methods. The results reveal that deceleration (or stop acceleration) events before the uphill crest occur in more than 80% of the uphill sections when there is no other interference. This phenomenon occurs because the participant’s sight distance is restricted in these segments. The location of the slow-down segment was closely dependent on the slope gradient and the driving speed. In the slow-down segments, the participants have the longest fixation time and the lowest saccade and blink time compared with those in front of and behind the slow-down segments. Moreover, the driver’s HR increase is the highest. These results can serve as guidance for highway designers who develop safety measures for uphill sections.