In-vehicle Alerts for Conditionally Automated Vehicles

<p>How the capabilities and limitations of automated driving systems (ADSs) are communicated to users both before their initial use by developers and during their operation by their human machine interface (HMI) impact safety. Autonowashing has contributed to high profile crashes involving misuse of partial driving automation systems (L2),leading some drivers to over-trust currently available L2 advanced driver assistance systems (ADAS) relative to their capabilities. This could worsen with conditional ADSs (L3) that might require driver intervention when operational thresholds are reached while being automated most of the time. Participants in this simulator study were provided introductory information via video that communicated the driver’s role at different levels of automation, the capabilities and limitations of the simulated L3 ADS, and its graded warning system. This video ended with either an explicit reminder of the driver’s responsibilities when using conditional driving automation (L3 reminder condition) or highlighted benefits that might arrive with higher levels of driving automation (L4+ capabilities condition). Significant differences were found in subjective ratings of familiarity, with participants in the L4+ capabilities condition reporting greater levels of familiarity over the course of the experiment (though still low) than their L3 reminder condition counterparts. Participants often resumed vehicle control when the ADS communicated uncertainty, and there were few differences in take-over performance or monitoring behavior between conditions. Participants’ take-over performance improved in both conditions, emphasizing the beneficial effects of practicing such a maneuver.</p>