Comparison of Communication Modalities: Safe and Efficient Interaction between an Automated Vehicle and a Pedestrian

As the communication between automated vehicles and human road users becomes increasingly important, this study aimed to investigate the effect of different communication modalities on traffic safety and efficiency. A VR study was conducted wherein 37 participants interacted as pedestrians with an automated vehicle to evaluate implicit communication via lateral offset, explicit communication via an external human-machine interface, and a combination of both. The results indicate that the combined communication approach was ranked the highest in subjective evaluations, while the external human-machine interface achieved the best efficiency results. In terms of traffic safety, no differences were found between the different communication modalities. The study concludes that a combined communication approach, consisting of both implicit and explicit signals, can enable safe and efficient cooperation between traffic participants in future interactions between automated vehicles and pedestrians. However, in situations involving further agents, such as manual vehicles, clearer communication may be necessary. Overall, this study contributes to a better understanding of communication strategies for automated vehicles and provides insights for future research.