Study a Driver’s Response to Emerging Scenarios Under Different Levels of Perceived Urgency

Although intelligent vehicles have filled our daily lives, drivers are still required to take over when automation disengages. To provide effective decision supports in such emerging events with time pressure, how the drivers make reactions deserves more attention. This research aims to investigate the pattern of the drivers’ response to emerging events under different levels of perceived urgency. A total of 20 participants were recruited for simulated driving. For the outcomes obtained, three levels of urgency are considered. In cases of low-level urgency, it is found that the average lateral acceleration is the highest, while the values of standard deviation for both lateral acceleration and steering are the lowest. This implies that the drivers can execute active yet cautious operations. For the cases of medium level of urgency, the extent of deceleration is significantly higher. Even though, the driver can maintain the same level of lateral operations as the cases of low-level urgency. Lastly, as for the cases of high-level urgency, not only does the average lateral deceleration decrease but the standard deviation of lateral deceleration and steering increases. This combination implies the deterioration of lateral control, which might affect the overall traffic flow or even result in collisions like the rear end.