Exploring the effectiveness of external human-machine interfaces on pedestrians and drivers

Abstract

Previous literature provided the results that eHMIs can be an effective method in interacting with pedestrians. However, there remains a question whether eHMIs are also effective for other road users or not. Therefore, the present study aimed to explore subjective evaluations on eHMIs with two different perspectives, pedestrians and drivers around AVs. Subjective preferences to different types of eHMIs were investigated through an online survey. Nine types of eHMIs were designed based on the combinations of display location and sign format. The results showed that people have different attitudes towards eHMIs depending on their perspectives. The participants as driver evaluated the bottom condition negatively compared to the pedestrian, and the participants as pedestrians felt that icons are not a good option compared to the drivers. The findings of the present study contribute to design of eHMI considering various road users.