  In conditionally automated driving, drivers have difficulty in takeover
transitions as they become increasingly decoupled from the operational level of
driving. Factors influencing takeover performance, such as takeover lead time
and the engagement of non-driving related tasks, have been studied in the past.
However, despite the important role emotions play in human-machine interaction
and in manual driving, little is known about how emotions influence drivers
takeover performance. This study, therefore, examined the effects of emotional
valence and arousal on drivers takeover timeliness and quality in conditionally
automated driving. We conducted a driving simulation experiment with 32
participants. Movie clips were played for emotion induction. Participants with
different levels of emotional valence and arousal were required to take over
control from automated driving, and their takeover time and quality were
analyzed. Results indicate that positive valence led to better takeover quality
in the form of a smaller maximum resulting acceleration and a smaller maximum
resulting jerk. However, high arousal did not yield an advantage in takeover
time. This study contributes to the literature by demonstrating how emotional
valence and arousal affect takeover performance. The benefits of positive
emotions carry over from manual driving to conditionally automated driving
while the benefits of arousal do not.
