Policymakers advocate for the use of external Human-Machine Interfaces (eHMIs) to allow autonomous vehicles (AVs) to communicate their intentions or status. Nonetheless, scalability concerns in complex traffic scenarios arise, such as potentially increasing pedestrian cognitive load or conveying contradictory signals. Building upon precursory works, our study explores 'interconnected eHMIs,' where multiple AV interfaces are interconnected to provide pedestrians with clear and unified information. In a virtual reality study (N=32), we assessed the effectiveness of this concept in improving pedestrian safety and their crossing experience. We compared these results against two conditions: no eHMIs and unconnected eHMIs. Results indicated interconnected eHMIs enhanced safety feelings and encouraged cautious crossings. However, certain design elements, such as the use of the colour red, led to confusion and discomfort. Prior knowledge slightly influenced perceptions of interconnected eHMIs, underscoring the need for refined user education. We conclude with practical implications and future eHMI design research directions.

翻译：政策制定者倡导使用外部人机界面（eHMIs），使自动驾驶汽车（AVs）能够传达其意图或状态。然而，复杂交通场景中出现了可扩展性问题，例如可能增加行人认知负荷或传递矛盾信号。基于前期研究，本研究探索了“互联eHMIs”概念，即通过连接多个AV接口，为行人提供清晰统一的信息。我们通过虚拟现实实验（N=32）评估了这一概念在提升行人安全性和过街体验方面的有效性，并将其与无eHMIs和非互联eHMIs两种条件进行对比。结果表明，互联eHMIs增强了安全感，鼓励了谨慎过街行为。然而，某些设计元素（如红色使用）引发了困惑与不适。先验知识对互联eHMIs的感知影响较小，凸显了精细化用户教育的必要性。最后，我们总结了实际应用意义及未来eHMI设计的研究方向。