ABSTRACT：Cell phone use while driving is becoming a key problem for traffic safety. To identify the characteristics of driver’s phone use; analyze its influence on driving performance, and explore factors influencing drivers’ speed change during phone use, 52 drivers’ 1,244 phone use events from the first naturalistic driving data in China was used. Because different subtasks within a task may cause different visual-manual distractions, a hierarchical coding structure for phone-use events was built. A total of 5,662 eyes-off-road cases, and 4,237 subtasks were extracted. The results show that on average, the drivers used phone for 6.08% of their driving time and the average eyes-off-road time was 3.16 s, which is equivalent to driving blindly for 22.82 m while using a cell phone. Also, the driver used phone for 17% of phone use time. The phone use had effects on longitudinal and lateral driving performance. The results showed that mean speed, mean and maximum headway did not significantly change during phone use while the standard deviation of speed, headway and lane offset, and mean and maximum lane offset were significantly lower during phone use. This indicates that drivers with phone use operated the vehicles with less fluctuation. The factors influencing the speed change were further studied using a decision tree model. It was found that speed change varied with the type and duration of phone-use tasks, duration of the trip and roadway type.
Yilun Xing, Xuesong Wang*, Chris Lee. Characteristics of Drivers’ Cell Phone Use and Their Influence on Driving Performance: A Naturalistic Driving Study. Transportation Research Board 98th Annual Meeting, Washington D.C., USA, 2019. 1.13-17.