Drivers' behavioural reactions to unexpected events

Many subtasks are relevant simultaneously when driving at urban intersections. Advanced Driver Assistance Systems (ADAS) can support the driver in this complex task. For a well-guided development and evaluatoin process of ADAS, insight into how different driving tasks influence each other is needed. Earlier research has shown that the interaction between different subtasks is changed by unexpected events. A driving simulator experiment was conducted to determine how gender, workload and event urgency influence this. Participants’ reactions to two unexpected events were measured. Participants temporarily changed their driving behaviour in reaction to the event. Urgency of the event increased this effect; workload changed the length of adjustments to the event. An interaction effect was found between workload and urgency: participants with high workload drove smoother, unless urgency of the unexpected event reached a threshold. No influence of gender was found.