Angle Adjustment Algorithms In Adaptive Front-lighting Systems

With the increase of vehicle speed and the complexity of road, the traditional headlamp can’t ensure safety without rotate function when vehicle is driving. Adaptive front-lighting systems can achieve the optimal illumination by swiveling the headlamps according to driving status and road conditions. Therefore, its study is of great significance to improve illumination and the safety of night driving.This dissertation takes angle algorithm, which is the core technology of adaptive front-lighting systems, as the study object and mainly focuses on the research of adaptive horizontal and vertical angle adjustment of headlamps. The main work and achievements are listed below:1. The method of calculating the turning radius of vehicle is presented, which is based on two-degrees-of-freedom dynamic model of vehicle. Combined with the geometric model when vehicle drives on curve road, formula of calculating the adaptive adjustment angle on the basis of speed and steering wheel angle is further derived.2. In accordance with the national standard GB4599-94, formula of calculating the adjusted angle of headlamps is derived when vehicle moves at high speed. Then based on four-degrees-of-freedom vibration model of half vehicle, the adjustment angle is deduced when vehicle’s posture is changed. When ramp appears in the front, information about the distance from vehicle and the ramp slope is acquired by infrared detector. Lastly the corresponding formula of adjustment angle is derived.3. Simulation results by MATLAB/Simulink show that the angle adjustment algorithms are valid. The whole control program of angle adjustment is simulated under Lab VIEW, which lays the theoretical foundations for the realization of angle algorithms on the prototype platform of AFS system. Finally horizontal servo is realized on the prototype platform.