External HMI for Automated Vehicles: Adding a Communication Perspective for all Road Users

Abstract

In this paper, we address the need for a common communication framework for all road users when interacting with automated vehicles (AVs). Our vision is to work towards a unified, comprehensive, and efficient external human-machine interface (eHMI) that can be commonly used and understood by all. A unified concept is needed since an AV will drive in mixed traffic (coexistence of AVs, pedestrians, cyclists, manually driven vehicles and motorcycles). Since manually driven vehicles (MDVs) will be one of the main road user groups (e.g. due to the first applications on motorways), it is important to consider this target group in research. Although some researchers have begun to focus on AV-MDV interaction to fill the gap in recent years, existing studies are still limited. This paper will summarise existing studies of eHMI with a specific focus on MDV and add this to the large existing research field of AV-VRU interaction. Existing literature is classified and summed up around two main aspects: 1) locations and scenarios of encounters; 2) task requirements of AV-MDV interaction. They can describe and help us get a more comprehensive understanding of AV-MDV interaction. Based on the literature review, the existing research gaps are summarized to develop new approaches for a more unified eHMI.

Keywords: Autonomous driving, Automated vehicle (AV), Vulnerable road user(VRU), Driving behavior, External Human-Machine Interface (e-HMI)

DOI: 10.54941/ahfe1001922