Effect of Warning Levels on Drivers' Decision-Making with the Self-driving Vehicle System

This paper introduces a systematic study on the influence of interface warning levels on users' decision-making in self-driving vehicles. Three scenes are designed in the driving simulator with the warning level interfaces displayed in each scene in a sequence. The lateral and longitudinal control of the driving simulator can be managed either by an automated controller in the self-driving mode or by the driver in the manual mode. A simulated driving experiment is performed with 23 participants. Their driving behavior data under different warning level interfaces are collected for empirical research. Results show that in the self-driving mode, the first level warning interface produces significant effect on users' driving behavior. Therefore, they usually take over control of the vehicle more quickly, the average speed becomes lower and the larger deviation of the vehicle from road center may appear after the take-over.