The Bending Mode Control Method of AFS System Based on Preview Control

Due to the time-lag of both the mechanical transmission and controller area network (CAN) bus transmission of the Adaptive Front Lighting System (AFS), the actual bending angle of AFS invariably lags behind the steering-wheel angle, which not only makes the real-time response speed of the AFS system slow, but also makes the system stability and the active safety of the vehicle poor.

To solve the problem, firstly, the geometrical relations among safety braking distance and the rate of steering-wheel angle and turning radius of the vehicle are analyzed. Secondly, the mathematics model among these variables has been set up. Finally, in order to improve the road illumination of the curve, the control method of bending mode of AFS system based on preview control is proposed. Based on preview control algorithm, the simulation model of the AFS has been built as well as the AFS control experiment platform. After the comparison between preview control and servo control, it can be proved that the preview control method proposed is superior to traditional servo control in AFS system.