The Effects of Continuous Driving-Related Feedback on Drivers’ Response to Automation Failures

Abstract

During prolonged periods of autonomous driving, drivers tend to shift their attention away from the driving task. As a result, they require more time to regain awareness of the driving situation and to react to it. This study examined the use of informative automation that during Level-3 autonomous driving provided drivers with continuous feedback regarding the vehicle’s actions and surroundings. It was hypothesized that the operation of informative automation will trigger drivers to allocate more attention to the driving task and will improve their reaction times when resuming control of the vehicle. Sixteen participants drove manual and autonomous driving segments in a driving simulator equipped with Level-3 automation. For half of the participants, the informative automation issued alerts and messages while for the other half no messages were issued (control). The number of on-road glances served as a proxy for drivers’ attention. Drivers’ performance on handling an unexpected automation failure event was measured using their time-to-brake and time-to-steer. Results showed that drivers using the informative automation made more frequent on-road glances than drivers in the control group. Yet, there were no significant differences in reaction times to the automation failure event between the groups. Explanations and implications of these results are discussed.