Exploring safer visual feedback in human-machine handover in highly autonomous vehicles

Abstract

Driving is becoming increasingly automated and the automated driving system is gradually replacing the driver, which will inevitably have a significant impact on the driving experience. This study investigates the design of a dashboard for the highly automated vehicle that would provide the driver with relevant information during the human-machine handover. After reviewing previous studies, analyzing the state-of-the-art and generating user scenarios, we developed design guidelines, prototypes and user experience videos. This video served as a "research instrument" to test with users and explore and learn about consequences and interpretations. The test results suggest that the mental workload paid by the user for the task shows a trend of reduction from level 3 to level 4. The reduced workload can ensure more effective alerts and alarms, which can potentially make driving safer. Regarding the implementation of the design, conclusions are mainly drawn on three aspects: the necessity to combine several modalities at automation level 4, the need to redefine the color of the assisting AR bars we designed due to the indistinguishability of the red and orange ones, and the disagreement on whether and how to display speed information at handover. The practice and application of our prototype in scenarios supports previous studies and provides a reliable, creative solution for other researchers and designers.