Age-related differences in effects of non-driving related tasks on takeover performance in automated driving

• Published in: Journal of safety research Vol. 72; pp. 231 - 238
• Main Authors: Wu, Yanbin, Kihara, Ken, Hasegawa, Kunihiro, Takeda, Yuji, Sato, Toshihisa, Akamatsu, Motoyuki, Kitazaki, Satoshi
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.02.2020; Elsevier Science Ltd
• Subjects: Age; Age-related differences; Automated driving; Automation; Automobile industry; Collision avoidance; Computer & video games; Driver fatigue; Drivers; Driving ability; Drowsiness; Eyeblink duration; Interfaces; Middle age; Non-driving related task; Older people; Performance degradation; Reaction time; Reaction time task; Simulator fidelity; Sleep and wakefulness; Steering; Drowsiness; Non-driving related task; Automated driving; Age-related differences; Eyeblink duration
• ISSN: 0022-4375; 1879-1247; 1879-1247
• DOI: 10.1016/j.jsr.2019.12.019

•Eyeblink duration was used to evaluate drowsiness development in automated driving.•Non-driving related task engagements countered younger drivers’ drowsiness.•Non-driving related task engagements delayed older drivers’ reaction times.•Age-related differences need to be considered for human-automation interactions. Introduction: During SAE level 3 automated driving, the driver’s role changes from active driver to fallback-ready driver. Drowsiness is one of the factors that may degrade driver’s takeover performance. This study aimed to investigate effects of non-driving related tasks (NDRTs) to counter driver’s drowsiness with a Level 3 system activated and to improve successive takeover performance in a critical situation. A special focus was placed on age-related differences in the effects. Method: Participants of three age groups (younger, middle-aged, older) drove the Level 3 system implemented in a high-fidelity motion-based driving simulator for about 30 min under three experiment conditions: without NDRT, while watching a video clip, and while switching between watching a video clip and playing a game. The Karolinska Sleepiness Scale and eyeblink duration measured driver drowsiness. At the end of the drive, the drivers had to take over control of the vehicle and manually change the lane to avoid a collision. Reaction time and steering angle variability were measured to evaluate the two aspects of driving performance. Results: For younger drivers, both single and multiple NDRT engagements countered the development of driver drowsiness during automated driving, and their takeover performance was equivalent to or better than their performance without NDRT engagement. For older drivers, NDRT engagement did not affect the development of drowsiness but degraded takeover performance especially under the multiple NDRT engagement condition. The results for middle-aged drivers fell at an intermediate level between those for younger and older drivers. Practical Applications: The present findings do not support general recommendations of NDRT engagement to counter drowsiness during automated driving. This study is especially relevant to the automotive industry’s search for options that will ensure the safest interfaces between human drivers and automation systems.