An Automatic Leveling System for Automotive Headlight Based on the Suspension Height Measurement

The Automatic Leveling System (ALS) is applied to the vehicle headlight to provide an adaptive control when driving at night. The ALS detects the pitching attitude of the vehicle, and drives the stepping motor integrated in the headlight to output a compensation angle. This compensation angle can adjust the headlight illumination angle and maintain a stable lighting range. In this paper, An automotive headlight leveling system based on the vehicle suspension height measurement is proposed. The hall sensor is introduced to realize the measurement of the front and rear suspension heights. The difference of the front and rear heights is then converted to the illumination angle of the headlight. To keep stable illumination range, an compensation angle is calculated and mapped to the rotation steps of the stepping motor in the headlight. The leveling system proposed in this paper can be widely used in the automotive headlight systems.