  Interactions between pedestrians and automated vehicles (AVs) will increase
significantly with the popularity of AV. However, pedestrians often have not
enough trust on the AVs , particularly when they are confused about an AV's
intention in a interaction. This study seeks to evaluate if pedestrians clearly
understand the driving intentions of AVs in interactions and presents
experimental research on the relationship between gaze behaviors of pedestrians
and their understanding of the intentions of the AV. The hypothesis
investigated in this study was that the less the pedestrian understands the
driving intentions of the AV, the longer the duration of their gazing behavior
will be. A pedestrian--vehicle interaction experiment was designed to verify
the proposed hypothesis. A robotic wheelchair was used as the manual driving
vehicle (MV) and AV for interacting with pedestrians while pedestrians' gaze
data and their subjective evaluation of the driving intentions were recorded.
The experimental results supported our hypothesis as there was a negative
correlation between the pedestrians' gaze duration on the AV and their
understanding of the driving intentions of the AV. Moreover, the gaze duration
of most of the pedestrians on the MV was shorter than that on an AV. Therefore,
we conclude with two recommendations to designers of external human-machine
interfaces (eHMI): (1) when a pedestrian is engaged in an interaction with an
AV, the driving intentions of the AV should be provided; (2) if the pedestrian
still gazes at the AV after the AV displays its driving intentions, the AV
should provide clearer information about its driving intentions.
