Fatigue and mental underload further pronounced in L3 conditionally automated driving: Results from an EEG experiment on a test track

TL;DR

This EEG study reveals that L3 conditionally automated driving induces greater fatigue and mental underload than L2 and manual driving, highlighting challenges for driver monitoring and interface design.

Contribution

The study provides novel insights into brain activity changes during L3 automation, emphasizing fatigue and mental underload issues not previously well-characterized.

Findings

Decreased mental workload in L3 compared to L2 and manual driving.

Increased sleepiness during L3 driving indicated by EEG and self-report.

Alterations in frontal alpha and theta power spectral density in L3 condition.

Abstract

Drivers' role changes with increasing automation from the primary driver to a system supervisor. This study investigates how supervising an SAE L2 and L3 automated vehicle (AV) affects drivers' mental workload and sleepiness compared to manual driving. Using an AV prototype on a test track, the oscillatory brain activity of 23 adult participants was recorded during L2, L3, and manual driving. Results showed decreased mental workload and increased sleepiness in L3 drives compared to L2 and manual drives, indicated by self-report scales and changes in the frontal alpha and theta power spectral density. These findings suggest that fatigue and mental underload are significant issues in L3 driving and should be considered when designing future AV interfaces.