  In this article, we report on the design and evaluation of an external
human-machine interface (eHMI) for a real autonomous vehicle (AV), developed to
operate as a shared transport pod in a pedestrianized urban space. We present
insights about our human-centered design process, which included testing
initial concepts through a tangible toolkit and evaluating 360-degree
recordings of a staged pick-up scenario in virtual reality. Our results
indicate that in complex mobility scenarios, participants filter for critical
eHMI messages; further, we found that implicit cues (i.e., pick-up manoeuvre
and proximity to the rider) influence participants' experience and trust, while
at the same time more explicit interaction modes are desired. This highlights
the importance of considering interactions with shared AVs as a service more
holistically, in order to develop knowledge about AV-pedestrian interactions in
complex mobility scenarios that complements more targeted eHMI evaluations.
