A Shared Differential Steering Assistance Method Considering Driver's Fatigue Behaviors

To improve road traffic safety a nd reduce t he risk of vehicle instability caused by driver fatigue, a differential-assisted steering shared control method considering the differen-tial characteristics of driver fatigue was proposed in this paper for independent wheel-drive vehicles with differential steering functions. The method can provide individualized steering assis-tance to enhance the driver's path-tracking capability. Firstly, driver-vehicle coupling was modeled based on a preview model that characterizes fatigued driving. Secondly, considering the delay time differences caused by driver fatigue, change in the longitudinal speed of the vehicle, and the uncertainty, a full-order dynamic output feedback robust controller was designed. Matlab/Simulink-CarSim simulation and Driver-in-the-loop test were used to verify the performance of the designed differential steering shared controller. The results show that the proposed controller can optimize the driver's path tracking accuracy by 59.5 % - 78.2 % and provide appropriate individual assistance at different longitudinal speeds and different driver states. The performance of the closed-loop human-vehicle system in fatigue situations was improved.