Vertical Aim Control

Since 1998 the ECE-Regulation R48 requires the compensation of vehicle inclination caused by different loading conditions. The purpose of this regulation is on one hand to avoid glaring of oncoming traffic and on the other hand to ensure an optimum range of illumination. For Halogen headlamps it is allowed to realize this vertical aim control (VAC) as manual controlled, whereas an automatic VAC is required for Xenon headlamps. For this reason Automotive Lighting offers three types of VAC:

Manual Vertical Aim Control

This type of VAC is required for Halogen headlamps. The driver uses a rotary or slide switch to adjust the headlamps according to the tilt of the vehicle. Therewith an extreme vehicle inclination is compensated. For manual levelling, electric motors (VAC 3rd generation) that are produced by Automotive Lighting in Reutlingen, Venaria, Malaysia and Sosnowiec, are used as actuators. This VAC 3 is a standard component and is integrated inside the headlamp.

Automatic Vertical Aim Control

Due to their increased brightness, an automatic vertical aim control is required in the case of Xenon headlamps. First, axle sensors detect the angle of the chassi. An electronic control unit (ECU) that calculates the vehicle´s tilt, and compares this with the predefined value. Positioning motors that maintaim the correct headlamp setting. Automotive Lighting offers two different equipment levels:

            - Static Automatic Vertical Aim Control

Any changes in the vehicle tilt caused by changes in loads are compensated in order to fulfil the headlamp vertical aim control regulations. The lifetime of the positioning elements is extended relatively to the manual headlamp vertical aim control.

            - Dynamic Vertical Aim Control

In addition to legal requirements, changes in the vehicle´s tilt by accelerating or deccelerating can be compensated with a dynamic vertical aim control. Particularly in full brake application, the vehicle can incline at 1,5° to the front. In this critical situation the range of illumination of the road decreases dramatically starting from 100m to less than 40m. An immediate movement of both headlamps 1,5° upwards keeps the range of illumination on its original length. In this case the headlamps must be moved much faster than for static automatic leveling. The required dynamic can only be fulfilled by a stepper motor.

Dynamic automatic headlamp vertical aim control

1. Rear axle sensor
2. Electronic control unit – ECU
3. Speed signal
4. Front axle sensor
5. Actuator
6. Headlamp