Driving (and) Attention – Does Directional Illumination Support Driver’s System Supervision When Driving Automatically?

Abstract

Partially automated driving changes the driving task into supervising the automation with occasionally a necessity to intervene. Due to this changing role, drivers of partially automated vehicles have need for interfaces that help them to supervise system operation, support detection of relevant events, as well as provide cues about system’s intentions. This study assessed to what extent directional illumination supports drivers in gaining mode awareness, i.e. in perceiving and understanding what the automation does and whether counter actions are necessary. An internet survey with video-clips of directional illumination within circumstances representative for partially automated driving measured respondents’ understanding of automation-mode and their understanding of required action. Measurements were compared with results from a base-concept, which provided cues for automation mode, but without directional illumination. Results showed that directional illumination raised perception and understanding of automation-mode noticeable when attention was requested for hazards located in the driver’s side-views. Compared to the base-concept, directional-illumination did not improve driver’s understanding of required actions. Development of explanatory instructions was recommended especially for events when changing road-situations interplayed with behaviour of other road-users. To attract attention to situations outside the vehicle, directional illumination was perceived significantly more suitable than the base-concept. The results of this study contribute to further development of directional illumination as a supporting interface while supervising partially automated driving.