Don't Worry, Just Follow Me: Prototyping and In-the-Wild Evaluation of Smart Pole Interaction Unit with Mobility

Pedestrian–automated vehicle (AV) encounters in shared spaces often involve hesitation and ambiguity. Vehicle-mounted external human–machine interfaces (eHMIs) can help, but obscured or poorly timed communications create significant challenges. To address this, we present a mobile smart pole interaction unit (SPIU) with integrated cameras and LED displays, designed as a pedestrian-side system to deliver explicit cues (“WALK,” “STOP”). An in-the-wild evaluation of the SPIU (N = 21) using a four-factor analysis (CarBehavior, Mobility, eHMI, SPIU) showed that the SPIU improved understandability, trust, and perceived safety, and reduced workload compared with the baseline, with a combination (eHMI+SPIU) yielding the strongest results. Beyond these quantitative benefits, participants appreciated the mobility of the SPIU for its “clear” and “easy to decide” mediation. This work contributes to (1) a design and deployment framework for a mobile SPIU and (2) an in-the-wild evaluation protocol for pedestrian–AV interactions in nonsignalized spaces. Our work sparks discussions on real world evaluations involving detailed vehicle kinematics and accessible multimodality (e.g., audio), focusing on the role of personal robots as user-side eHMIs.