Manual takeover and handover of a simulated fully autonomous vehicle within urban and extra-urban settings

Abstract

Relatively little is known about human behavior and performance when retaking control of highly autonomous vehicles (AVs) at different speeds and under varied driving conditions. Past research has tended to focus on long periods of high-speed extra-urban autonomous driving before participants switch to manual mode. The current study investigated time to ‘takeover’ (reengage with vehicle controls) and ‘handover’ (regain baseline level of driving) when switching frequently between automated and manual modes within extra-urban and slower urban settings. Thirty-one drivers completed scenarios at different speeds (20–30-mph/urban; 40–50-mph/extra urban). Dependent measures included speed and lateral lane position. Takeover time was consistent in 30–50-mph conditions (~2-seconds) but significantly slower at 20-mph. Some other measures took 15–20-seconds to match baseline in 20–30-mph conditions and participants tended to drive slower than recommended speed limits after takeover. Baseline performance was not achieved at 50-mph. Implications for handover system design and AV insurance frameworks are discussed.