Validating OESDs in an on-road study of semi-automated vehicle-to-human driver takeovers

Design of appropriate interaction and human–machine interfaces for the takeover of control between vehicle automation and human driver is critical to the success of automated vehicles. Problems in this interfacing between the vehicle and the driver have undoubtedly led to collisions and deaths. In this project, operator event sequence diagrams (OESDs) were used to design the takeover activities to and from vehicle automation. Previous work undertaken in driving simulators has shown that the OESDs can be used to anticipate the likely activities of drivers during the takeover of vehicles control. Three such studies showed that there was a strong correlation between the activities drivers represented in OESDs and those observed from videos of drivers in the takeover process, in driving simulators. For the current study, OESDs were constructed during the design of the interaction and interfaces for the handover of control to, and takeover from, vehicle automation. Videos of drivers during the takeover were taken on motorways in the UK and compared with the predictions from the OESDs. As before, there were strong correlations between those activities anticipated in the OESDs and those observed during the takeover of vehicle control from automation by the human driver. This means that OESDs can be used with some confidence as part of the vehicle automation design process, although validity generalisation remains an important goal for future research.