Strategies to Assist Drivers in Remaining Attentive While Under Partially Automated Driving: Verification of Human–Machine Interface Concepts

Visual inattention is a major concern with partially automated driving systems that assume vehicle steering functions. The safety concept for these systems capable of maintaining vehicle lane position and headway depends on an attentive driver who detects and appropriately responds to objects and events that are beyond the limitations of the sensors. Embedded within a proposed system are features designed to help drivers perform these functions and remain attentive to the driving environment. This study served to validate human–machine interface (HMI) strategies and concepts that can be applied to production-intent partially automated system HMI to achieve intended safety goals in assisting drivers to maintain attention to driving. Previous validation efforts, conducted as part of a NHTSA study, proved insufficient for verification of these driver performance functions since they relied on an incomplete version of alternative HMI concepts. The current study, with a sample of 25 licensed drivers, used approaches that more closely approximated the potential production-intent partially automated HMI concepts, including the introduction of consequences for failing to respond to alerts. Work was performed by using an advanced prototype capable of mimicking the basic functions afforded in a partially automated system. Driver responses to unexpected lane drift events were also examined. Results found that HMI concepts that introduce consequences for driver nonresponse situations substantially increase driver compliance to system cues, prompts, and alerts. Results of this study suggest that the potential production design partially automated system HMI concepts can assist drivers in maintaining their attention to driving.