Reproducibility of Driving Profiles – Application of the Wizard of Oz Method for Vehicle Pedestrian Interaction

Abstract

Wizard of Oz (WoZ) studies are a method used to examine pedestrians’ understanding of the different driving behaviors of automated vehicles (AV). In this WoZ study, a human driver, hidden behind a seat cover, repeatedly followed predefined trajectories. First, we asked the participants to rate different AV driving behaviors from a pedestrian’s perspective. Then we examined the performance of the human driver in following the trajectories. The results showed that 98 % of pedestrians understood the intentions of an AV by judging the driving behavior, if the trajectory met certain criteria. Ambiguous driving profiles decreased the recognition rate to 26 %. Furthermore, the driver followed diverse trajectories of differing qualities. The results also demonstrated that more complex trajectories were harder to follow. Reducing speed until reaching the exact point of a complete standstill appeared to be problematic. In conclusion, the findings suggest that WoZ studies are a useful way to evaluate large differences in trajectories, but are not suited to evaluating slight speed or acceleration differences.