Comparing driver reaction and mental workload of visual and auditory take-over request from perspective of driver characteristics and eye-tracking metrics

Abstract

The objective of this study was to compare the driver’s reaction and mental workload of different take-over requests (TOR) modalities concerning driver characteristics in semi-autonomous driving when the driver is engaged in different non-driving related tasks. A driving simulator was developed for two TOR modalities (visual and auditory). Thirty-three individuals participated in the driving simulation experiment. NASA Task Load Index, driver characteristics (driving style questionnaire and work-load sensitive questionnaire), and eye-tracking metrics were collected. Through the structural equation model, we found that driving style affects driver’s mental work-load and reaction sequence in a visual TOR alert situation, while in auditory TOR alert situation, a driver characteristics have no significance on mental workload and reaction sequence. Strong correlation between mental workload and reaction sequence was only found in the auditory TOR alert situation. These results can be used to develop an adaptive multi-modal interface that take driver characteristics into account.