Modeling The Effects Of Driver Distraction On Driving Safety

In recent years,with the extensive use of In-Vehicle Information System(IVIS),the induced driver distraction impairs road traffic safety severely,which has become one of the main contributors to traffic accident.To explore the influence of driver distraction on traffic accident and the underlying mechanism,the present study has conducted systematic experiments for investigating distracted driving on both normal driving condition and traffic conflict condition.The effects of driver distraction on both lateral and longitudinal driving performances,and their underling mechanisms on normal driving condition,are illustrated,thus revealing the mechanism of distraction causing the formulation of traffic conflict.Furthermore,the influences of distraction on drivers' response and crash probability under traffic conflicts conditions are illustrated.Based on a simulated city-road car following scenario,both driver's lateral and longitudinal performance are investigated experimentally.Statistical test method is used,so that different types and degrees of distraction can be considered.The adverse effects of visual-related distractions on driver's lateral and longitudinal performance are illustrated,thus revealing the mechanism of visual-related distraction leading to the formulation of traffic conflict.In addition,different methods for time-to-line crossing calculation are compared,thus vehicle's lateral safety indicator is extracted.Based on it,we observe reduction in both time-to-line crossing and standard deviation of lateral position during cognitive distraction.Besides,the conclusion that visual distraction dominates cognitive-visual combined distraction is verified in our results.The mechanism underlying distracted lane keeping is investigated by mathematical model,from the aspect of driver's visual and physiological behavior.The visual mechanism of visual distraction affecting driving performance is illustrated,while the temporal dynamics of gaze concentration,arousal,micro-steering activity,and lane keeping performance is revealed,through analyzing eye movement and skin conductance data.Mean while,micro-steering activity models and lane keeping performance models are constructed,based on the existing hypotheses.The best model for explaining changes in lane keeping performance is determined,by model comparison method,thus revealing the underlying physiological mechanism of cognitive distraction affecting driving performance.Distracted driver's response and crash risk,under typical traffic confits,are investigated systematically,by using experimental and modeling method.Driver's brake reaction time and crash risk models are constructed,with the consideration of types of distraction,situational urgency(including different driving speed,following time headway,and lead vehicle deceleration),and lead vehicle brake light states,in lateral pedestrian crossing and longitudinal rear-end conflicts.As a result,we reveal the mechanism of distraction affecting driver's reaction time and crash risk.In addition,based on these models,we propose the theoretical compensation of time headway in distracted driving.These will provide bases for the monitor of distraction-related driving risk and the design of driver's reaction time in advanced driver assistant systems.