Exploring the use of augmented reality interfaces for driver assistance in short-notice takeovers

With conditionally automated vehicles (Level 3), drivers are still required to be ready to intervene upon a takeover request (TOR) and face the difficulty of achieving their optimal performance level directly after a passive phase. In this work, we examine the effects of using an augmented reality (AR) interface with world-registered visualizations to assist drivers in the last moments before a takeover and in the first seconds of controlling the vehicle. We focus on urban situations with an unplanned, short-notice TOR and created three distinct example scenarios in a mixed-reality driving simulation. We present a prototype of an AR assistance system realized on a simulated windshield display (WSD). In a user study, we compare the AR system to a conventional head-down display (HDD) and present results on driving performance, driver workload and usability. The AR assistant enabled higher lateral performance and reduced workload in situations where steering is required directly after takeover but prolonged reaction time when only fast longitudinal input was required. The AR interface performed better than the HDD in most user-centered aspects including comfort of use and helpfulness.