To bridge the gap between autonomous and normal steering during low lateral acceleration maneuvers, a steering-wheel torque controller is developed. It consists of three controllers in series, a high-gain feedback steering-wheel torque controller, a nonlinear steering-angle controller, and a linear yaw-rate controller. A validated two degrees of freedom steering-system model, in combination with a single-track vehicle model, is used to determine the controller parameters. Driving tests with different drivers have been executed to find a comfortable steering-wheel torque/angle relation. This relation is maintained throughout the lane change by specifying the steering-wheel torque as a function of the steering-wheel angle tracking error. Experiments show promising results regarding the driver/vehicle interaction, but also show that a system to detect the lanes and the vehicle position on the road is required for further improvement.
Bibliographical noteFunding Information:
This research was supported by the Netherlands Organisation for Scientific Research (NWO) under Grant 12831.
© 2016 IEEE.
- autonomous driving
- Electric power-steering
- lane change
- steering-system model
- steering-wheel feedback torque
- yaw-rate control