Characterization of Driver Steering Control of Articulated Freight Vehicles Based on a Two-Stage Preview Strategy

A two-stage preview strategy is proposed to characterize steering control properties of commercial vehicle drivers. The strategy includes a near and a far preview points to describe the driver control of lateral path deviation and vehicle orientation. A human driver model comprising path error compensation and dynamic motions of the limb is subsequently formulated and integrated to a yaw-plane model of an articulated vehicle. The coupled driver-vehicle model is analyzed under an evasive steering maneuver to identify limiting values of the driver control parameters through minimization of a generalized performance index comprising driver's steering effort, path deviations and selected vehicle states. The performance index is further analyzed to identify relative contributions of different sensory feedbacks, which may provide important guidance for designs of driver-assist systems (DAS). The results show that the proposed model structure could serve as an effective tool to identify human control limits and to determine the most effective motion feedback cues. The results further imply that lateral position and heading angle of the lead unit are the most essential sensory cues to achieve satisfactory guidance and control of the vehicle, while the lateral acceleration and yaw rate of the vehicle can serve as secondary cues to enhance path tracking performance of the vehicle in emergency driving situations.