Relationship between speed, lateral placement, and drivers' eye movement at two-lane rural highways

A number of previous studies have investigated driver behaviors including speed and lateral placement in curved sections of highways. However, few studies attempted to empirically address relationships considering other factors, such as driver's eye-fixation distributions and illuminations, which are also believed to be relevant to highway safety. This study consists of field experiments to examine driver behaviors under different geometric and illumination conditions in two-lane rural highways. In the experiment, drivers' eye movements, which have been considered as surrogate of drivers' visual attention, are investigated by using a head-mounted eye-movement tracking system. Regression models are developed to show the relationship among the data, and the results show that there are significant differences in driver's eye movements under different geometric and illumination conditions. These findings give traffic engineers practical suggestions when implementing traffic control devices to increase safety on curved sections of two-lane rural highways.