Partial-autonomous Frenzy: Driving a Level-2 Vehicle on the Open Road

Partial-autonomous vehicles are among us and represent a prominent testing ground for assessing the human interaction with autonomous vehicles. One main limitation of the studies investigating would-be users’ attitude toward partial to full autonomous driving stems from their indirect experience with such technology. In this study, participants drove a partial-autonomous vehicle on the open road and interacted with both Adaptive Cruise Control (ACC) and Lane Keeping Assist (LKAS) systems. Preliminary results show participants rating level-2 autonomous features as possible sources of stress. Participants had issues engaging these systems with denser traffic and thought these systems to be more beneficial in traffic-free driving. Compared to ACC, engaging LKAS and monitoring its functioning represented a more challenging task and participants’ ratings of stress toward this system increased over time. Findings obtained in this study are of importance for exploring user interaction with future highly-autonomous vehicles and designing effective countermeasures to make the human-machine interface of these systems more informative and easier to use.