The Challenges of Driving Mode Switching in Automated Vehicles: A Review

The conversion between automated and manual driving is currently an inevitable topic for automated vehicles. Firstly, from the concepts, types, and key issues of driving mode switching, this paper points out that the current challenging issue with driving mode switching is the safe switch from automatic to manual driving mode. Secondly, the conditions and procedures for switching between manual and automated driving modes are described, and it is clarified that driving mode switching in automated vehicles with the L4 automation level and below is unavoidable. It is pointed out that there should be a human-machine co-driving state between driving modes and the driver should be provided the proper guidance to ease pressure while taking over, it is highlighted by summarizing driving mode switching strategies. Last, the methods of simulation scenario creation and evaluating the validity of the simulated experiment are summarized, and the current main use of takeover time and quality indicators to evaluate the driver's takeover performance is clarified. The influence of driver's workload and takeover time budget on takeover performance is summarized, and methods for enhancing takeover performance are also mentioned. This paper may provide a reference for autonomous vehicle control strategy design and driver takeover research.