Effect of Response Method on Driver Responses to Auditory Warnings in Simulated Semi-autonomous Driving

Abstract

We examined how drivers’ response to automation warnings could improve driver performance by testing the traditional direct-response method against a new indirect-response method. A direct response, for which drivers manually take over control of the car after hearing the warning and seeing the scenario, was compared to an indirect response, for which drivers press a “yes” or “no” button to assist the automation in making a correct choice. Results showed no reaction time (RT) difference between the response methods, but accuracy was better for the direct response. Subtracting the action-execution time from RT showed that the indirect response took longer to mentally process, explaining why the indirect method was not faster and pointing to a potential source of increased errors. Buttons presses in the indirect method could eventually be faster, but better ways to convey the warning to the user and improve the human-machine interface are needed in future research.