Designing An Informative Interface for Transfer of Control in Level 2 Automated Driving System

Although automated driving systems have made significant progress over the past few years, human involvement is still vital, especially for Level 2 (L2) systems. One of the challenges of L2 systems is transfer of control between drivers and systems. The objective of this study was to design and evaluate an in-vehicle interface for an L2 automated vehicle to increase situation awareness and help drivers identify and understand critical situations that require transfer of control. A comprehensive study was conducted in three Phases. In the first Phase, drivers’ behavior in simulated drives was analyzed using video recordings, interviews, and questionnaires. Three different road geometries were considered: curves, intersections, and merges. Following this Phase, four design iterations were developed in the second Phase of the study. The final prototype was applied to the dashboard of the driving simulator cab. The third Phase included a between-design experimental study to test efficiency of new dashboard designs. Forty-two participants were recruited and assigned randomly to three different groups based on dashboard design (Advanced, Basic, Original) and all participants in each group drove through seven scenarios. Results showed that providing take back control feedback (combination of visual and audio) helps drivers to be more situationally aware while driving L2 vehicles. Additional feedback regarding road geometry can also improve drivers’ take back control performance. The method and results of this study can help both researchers and manufacturers to gain more insight towards future designs of feedback systems in L2 vehicles