Transition to manual: Comparing simulator with on-road control transitions

Whilst previous research has explored how driver behaviour in simulators may transfer to the open road, there has been relatively little research showing the same transfer within the field of driving automation. As a consequence, most research into human-automation interaction has primarily been carried out in a research laboratory or on closed-circuit test tracks.

The aim of this study was to assess whether research into non-critical control transactions in highly automated vehicles performed in driving simulators correlate with road driving conditions.

Twenty six drivers drove a highway scenario using an automated driving mode in the simulator and twelve drivers drove on a public motorway in a Tesla Model S with the Autopilot activated. Drivers were asked to relinquish, or resume control from the automation when prompted by the vehicle interface in both the simulator and on road condition.

Drivers were generally faster to resume control in the on-road driving condition. However, strong positive correlations were found between the simulator and on road driving conditions for drivers transferring control to and from automation. No significant differences were found with regard to workload, perceived usefulness and satisfaction between the simulator and on-road drives.

The results indicate high levels of relative validity of driving simulators as a research tool for automated driving research.