Evaluation of communication between automated vehicles and pedestrians

In today´s traffic, drivers communicate with pedestrians explicitly through a variety of means, including gestures and eye contact or implicitly through the vehicle itself. Road users infer the driver´s intention from these communication cues. However, as the level of automation increases, the driver will no longer be in control of the vehicle behavior and will instead be engaged in non-driving related tasks. Nevertheless, automated vehicles (AVs) will still need to coordinate with other road users to ensure road safety and traffic flow, without relying on today´s driver-centric communication cues. In the recent years, many studies have focused on the design of vehicle behavior and additional external human-machine interfaces (eHMIs) to ensure the communication between AVs and pedestrians. In the vast majority of studies, interactions with AVs equipped with a communication interface were found to be more efficient and perceived as safer and more satisfying. To measure the effectiveness of communication, these studies asked participants to explicitly indicate their decision to cross the road. Research on the actual behavior of pedestrians has been neglected so far, probably due to the lack of precise data collection and analysis tools. This dissertation addresses the current state of research and has two aims. First, by presenting five empirical studies, the dissertation takes up the prevalent lack of actual behavior in previous research. It takes a deep dive into exploring pedestrian behavior when it comes to AV-pedestrian interaction, both in laboratory and real-world settings. Secondly, the dissertation deals with the research question of how AVs can communicate with pedestrians. Given that much of the current interaction between road users is based on the motion patterns of the vehicle, we propose to further investigate the role of its “body language” as a communication modality. In addition to eHMIs, we aimed to explore an implicit communication through an artificial vehicle motion, namely active pitch ...