Response to a critical situation during automated driving: can we take drivers out of the loop?* Tyron Louw, Natasha Merat, Georgios Kountouriotis, Ruth Madigan Institute for Transport Studies, University of Leeds, Leeds, UK // Introduction & Aims • Endsley, M. R., and Kiris, E. O. (1995). The out-of-the-loop performance problem and level of control in automation. Human Factors, 37(2), 381-394. • Lee, J. D., Regan, M. A., and Young, K. L. (2008). Defining driver distraction. In M. A. Regan, J. D. Lee, and K. L. Young (Eds.), Driver Distraction: Theory, Effects, and Mitigation(pp. 31–40). Boca Raton, FL: CRC Press. • Li, S. Y. W., Magrabi, F. and Coiera, E. (2012). A systematic review of the psychological literature on interruption and its patient safety implications. Journal of the American Medical Informatics Association: JAMIA, 19(1), 6–12. • 30 Participants (39.2yrs ± 14.45) • Driving experience: 20.17yrs ± 15.26 • Repeated measures, 3 X 3 mixed design • Vehicle automation is likely to induce mind- wandering, or stimulus-independent thoughts, which can interfere with processing external stimuli, such as roadway hazards (Li et al., 2012). • This out-of-the-loop (OOTL) state presents an issue to safety should the driver be called upon to resume manual control (Endsley & Kiris, 1995; Lee, 2013). But how does one study this given that inducing the OOTL state is difficult? // Results // Methods • There is also no objective measure of safety and quality of the transition of control from automation to manual driving 1. Can we induce the OOTL state by limiting system and environmental information? 2. How do drivers make decisions and react in the face of uncertain automation? 3. Are there other means of evaluating the transition to manual driving? Light Fog Heavy Fog 30s Automation On Lead vehicle action Uncertainty Alert EVENT START Ego vehicle Lead vehicle Screen Manipulation On 90s ≈30s EVENT END Screen Manipulation Off Non-critical Critical 1 2 3 4 5 6 7 ≈ 20 mins ≈150s // References Critical Event = Lead vehicle braked at TTC of 5s. Collision would occur unless driver intervened. Steering Wheel Colour Automation status Grey Unavailable Flashing green Available Green Engaged Flashing yellow Uncertain Red Disengaged • HMI: FCW & Automation Status • Inducing the OOTL state in automation: • Schematic representation of each discrete event Automation Automation Manual Manual Critical Event 1 Critical Event 2 Critical Event 1 Critical Event 2 Critical Event 1 Critical Event 2 Critical Event 1 Critical Event 2 Within-Subjects Factors: Drive & Event Within-Subjects Factors: Drive & Event Light Fog Heavy Fog Between-subjects factor: Condition Automation Status Hidden Light Fog Screen Occlusion Automation Status Hidden Heavy Fog Screen Occlusion Limited Visual Roadway Information Auditory and haptic cues still present • Were drivers OOTL? Percentage Road Centre during screen occlusion ‘Peeks’ at hidden automation status during screen occlusion • What did they do? In 16% of non-critical cases drivers disengaged automation compared to 100% in critical cases Automation Manual Critical Event 1 Critical Event 2 Critical Event 1 Critical Event 2 Light Fog 7 (2) 10 (1) 11 (1) 12 (0) Heavy Fog 9 (7) 9 (3) 11 (2) 11 (1) Lane Changes and collision counts (in brackets) • How did they do it? • Automation (vs. Manual) = ↑ Lateral Acceleration (p=.005) ↑ Deceleration (p=.001) ↓ Time headway (p=.011) *Paper to appear in the Proceedings of the Driver Distraction and Inattention Conference, Sydney 2015