Response of major road drivers to aggressive maneuvering of the minor road drivers at unsignalized intersections: A driving simulator study

Abstract

Drivers’ inattention, human error and aggressive behavior are often linked with vehicle crashes. This research studies how major road drivers respond to the aggressive maneuvering of the minor road drivers at unsignalized intersections. The study was also designed to investigate the effect of distracted driving (engaged on handheld phone) on driving performance. In our experiments, 51 drivers were tested for four different events using a driving simulator. The test track comprised of a stretch of 10.4 km having nine unsignalized intersections. A possible conflicting event was designed at each intersection for approaching major road drivers. The major road driver behavior was evaluated with reference to three variables: response time before possible conflict (RTPC), average speed while approaching intersection and at the intersection, and deceleration rate. The analysis results showed that the RTPC values against the right turning vehicles were very low indicating high risk against right turning vehicles (considering left side driving practice). For the same event with handheld phone conversation, the RTPC values were found to be negative indicating that the drivers are more likely to miss the visual reaction time stimuli when engaged in a phone conversation. The 10th and 90th percentile RTPC values were found to vary from 6.3 to 9.4 s and 0.1 to 1.8 s respectively for different events. The driving speed of the drivers was not found to be significantly impacted by the cell phone usage. The approach speed for all drivers at the intersection was found to be lower by 35–40% compared to speeds before responding to the conflicting vehicle. The average decelerating rate for all the drivers was found to be 3.73 m/s2 and 4.23 m/s2 when the participants were driving without phone and with phone respectively. The insights from this study can be used to understand pre-crash driver actions which are necessary for the implementation of appropriate countermeasures and to assess the level of safety at unsignalized intersections.