Pedestrian and Passenger Interaction with Autonomous Vehicles: Field Study in a Crosswalk Scenario

This study presents the outcomes of empirical investigations pertaining to human-vehicle interactions involving an autonomous vehicle (AV) equipped with both internal and external Human Machine Interfaces (HMIs) within a crosswalk scenario. The internal and external HMIs were integrated with implicit communication techniques, incorporating a combination of gentle and aggressive braking manoeuvres within the crosswalk. Data were collected through a combination of questionnaires and quantifiable metrics, including pedestrian decision to cross related to the vehicle distance and speed. The questionnaire responses reveal that pedestrians experience enhanced safety perceptions when the external HMI and gentle braking manoeuvres are used in tandem. In contrast, the measured variables demonstrate that the external HMI proves effective when complemented by the gentle braking manoeuvre. Furthermore, the questionnaire results highlight that the internal HMI enhances passenger confidence only when paired with the aggressive braking manoeuvre.