A Prototype Study on External Human Machine Interface (HMI) for Automated Bus - Preliminary Testing for Effectiveness Verification Using Virtual Reality (VR)

Autonomous vehicles face safety challenges due to a lack of clear communication with other road users, leading to conflicts, especially at un-signalized intersections. While much research focused on developing communication tools solely for vulnerable road users, this study focuses on developing external Human Machine Interfaces (eHMI) for comprehensive communications in real world. We developed and installed a real electronic LED display board on an autonomous bus to communicate the bus's intention with other road users. To expedite assessment, we created two virtual reality environments-one for optimizing prototype eHMI settings (e.g., its size, positioning, text, etc.) and another for quantitatively evaluating its effectiveness in deadlock situations. These environments complement the gradual accumulation of real-world interaction data. In the research demo, we will demonstrate a real-world new-accident interaction between an autonomous bus and a traditional vehicle, and visitors can experience the reproduced situation in VR with and without the prototype eHMI.