Implicit Communication of Automated Vehicles in Urban Scenarios: Effects of Pitch and Deceleration on Pedestrian Crossing Behavior

This Study analyzed the effects of AV's approach trajectories and the role of the vehicle's pitch on pedestrian's crossing behavior. 30 participants experienced an urban traffic scenario in the virtual reality simulator with vehicle convoys driving at 30 km/h. The decelerating vehicle approached the waiting pedestrian using three different kinematic trajectories, which were accompanied by four pitch conditions. The effect of an early or stronger vehicle pitch on the pedestrian crossing behavior was stronger when coupled with a defensive deceleration strategy. Overall, hard initial braking reduces the time, pedestrians need to understand an approaching vehicle's yielding intention. Active pitching might increase this effect, but requires further evaluation, as pedestrians link the vehicle's pitch to the perceived kinematics.