How to nudge a stressed driver to use automation?

Automated driving will offer safer driving. If level 4 automation is available, it will be recommendable to use it, especially for stressed or sleepy drivers. Still, the freedom of choice needs to be preserved, so it is likely that the use will depend on the driver’s choice. Nudging elements can push/direct drivers towards specific options/outcomes. For a safe and voluntary transition into automated driving we used nudging principles for a holistic HMI strategy that was iteratively developed with 3x12 subject design in a driving simulator. Stress and sleepiness were induced as a realistic environment for the nudging HMI. The iterative development resulted in an HMI strategy with nudging and coherent multimodal HMI elements, composed by ambient light, seat vibration, sounds and driver state icons. The paper describes in a case study how the potential of nudging theory can be used to increase the likelihood of using automated driving.