Driving a car can involve extreme fluctuations in mental workload and some vehicle manufacturers are attempting to develop systems that manage workload. Such systems are needed to manage the attentional processing demands placed on the driver both from outside the vehicle and within the vehicle. As the modern driving task is a driver-vehicle-environment interaction, this research explores the possible methods in quantifying the workload imposed by the dynamic environment. In this study, different methods of assessing the demands placed on drivers by traffic variables, particularly traffic density and lane change effects were examined. The changes in the driving demand resulting from the surrounding traffic were measured using subjective ratings and tactile detection task. The analysis presented here was based on subjective ratings and detection task response times, compared with data obtained from the simulator. The results showed that both main effects of traffic density and lane change were found to be significantly affecting the driving task difficulty, while subjective ratings was found to be the most sensitive measure of driver workload. (Author/publisher)
Samenvatting