Driver Response Times when Resuming Manual Control from Highly Automated Driving in Truck Platooning Scenarios.

Abstract

Automated platooning of trucks is getting increasing interest for its potentially beneficial effects on fuel consumption, driver workload, traffic flow efficiency and safety. Nevertheless, one major challenge lies in the safe and comfortable transitions of control from the automated system back to the human drivers, especially when they have been inattentive during highly automated driving. In this study, we investigated drivers’ take-over response times after a system initiated request to take back control in a non-critical scenario. 22 professional truck drivers participated in the truck driving simulator experiment and everyone was instructed to drive under three types of experimental conditions before the presentation of the take-over request: Driver monitoring (drivers were instructed to monitor the surroundings), Driver not-monitoring (drivers were provided with a tablet and were asked to use this) and Eyes-closed condition (they were not allowed to open their eyes). Driver take-over time components in terms of perception response times and movement response times were manually annotated from video recordings. Results showed significantly longer total takeover time and larger individual differences in both Driver not-monitoring and Eyes-closed conditions compared to the driver monitoring conditions. Movement time is found to be the one dominant factor, influenced by driver activities to resume physical readiness before taking over control. The large variability in take-over times between and within conditions suggests the importance of a personalized driver readiness predictor as input parameter for a safe and comfortable transition.