Dynamic Authority Allocation for Shared Steering Control Considering Driver Attention and Conflict Resolution

Vehicle automation can improve traffic safety and reduce the driver workload. However, the driver disengagement from the control loop will cause a significant risk under current technology. Shared steering control, which can realize the cooperative control of the vehicle by the driver and the intelligent system, is a research hotspot at present. This paper proposes a dynamic authority allocation strategy for shared steering control system considering driver’s attention level and conflict resolution. Firstly, a shared steering control model based on non-cooperative game theory is established and the obtained solution is given according to the Nash equilibrium. Thereafter, a driving risk field is built to accurately describe the real-time risk distribution of the driving scenarios. The driving risk field value can also be used to determine the correct side in the event of a human-machine conflict. On this basis, a dynamic authority allocation strategy based on fuzzy controller is designed. The cooperative driving is divided into two modes according to the difference of the human and machine’s target trajectories. Driver’s attention level, torque intention and the driving risk field are the inputs of the fuzzy controllers and a mapping function is built to transmit the output of fuzzy controller to the weighting matrix of the Nash equilibrium solution. Lastly, case studies based on CarSim and MATLAB/Simulink are performed to evaluate the performance of the proposed strategy compared with other strategies. The results indicate that the dynamic authority allocation strategy effectively alleviates the human-machine conflict and reduces the adverse effects of the driver’s low attention level.