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Intelligent light systems Automotive Lighting
INTELLIGENT LIGHT SYSTEMS
For about 25 years car manufacturers have offered, in addition to robust Halogen bulb based headlamps, alternative lighting options equipped with High Intensity Discharge lamps (HID) – called ‘Xenon’ light. For more than 10 years, electronically controlled Adaptive Frontlighting Systems (AFS) from Automotive Lighting with dynamic beam pattern variation have been improving driving safety during the night by enhancing visibility under different and difficult driving conditions. Nowadays, the new ILS-Systems are fully equipped with LED light sources.
“Since 2008, when Automotive Lighting started the production of the first all-LED headlamp for the Audi R8, the potential of semiconductor based light sources which offer vast terrain of styling opportunities with scalable performance and adaptable functionalities combining safety benefits with styling opportunities has grown,” said Johannes Geywitz-Senn, head of Marketing at Automotive Lighting, a division of Magneti Marelli Group.
Enhanced signal and adaptive main functions have been developed and offered with the aim of increasing driving safety during day and night. Adaptive lighting functions are adjusting the low beam pattern of headlamps according to the specific driving conditions.
Customised solutions for intelligent lighting systems
Automotive Lighting keeps developing lighting systems with typical brand signatures in close cooperation with carmakers all over the world. The carmakers offer a broad program of alternative solutions according to the needs of their customers. AFS-headlamps enhance driving safety and comfort, and provide an enormous added value. “For that reason they have become the standard in the flagship vehicles of Europe’s best carmakers and the option for nearly all car segments,” comments Ilona Rutkiewicz, responsible for Marketing Communication at Automotive Lighting. A few years ago, Volkswagen was the first carmaker that offered camera-controlled ‘Glarefree High Beam’ (GHB) as enhanced safety related technology has set a new standard within vehicle lighting technology. The UN/ECE-regulation R-123 permits lighting systems which encompasses various functions including: static bend light or cornering function, dynamic curve light, motor way light and glarefree high beam. (Pic.2) Using continuously improved elements of modular concepts, the set makers customise the desired lighting solution for each carmaker. Automotive Lighting incorporates innovative technologies in different scenarios which are in line with the particular DNA of carmakers’ vehicle programs.
How it works
All adaptive lighting functions are activated when the automatic mode is selected by the driver. The high class adaptive lighting systems use vertical and horizontal beam control. The function to which the most attention is paid is camera supported glarefree high beam. The camera located behind the windscreen monitors the traffic. Once oncoming traffic is detected, the camera sends the signals of their positions via CAN-Bus to the electronic control unit of the headlamp. Depending on the concept philosophy of the lighting system, the light distribution is controlled either electro-mechanically or electronically. During the electro-mechanical control, the integrated stepper motors are used to swivel or level the modules and to
adjust the shape of the cut-off-line. When controlling electronically, the LED light sources are dimmed or switched on and off in order to offer the best visibility to the driver and to limit glare for other drivers.
VW: the initiator of glarefree high beam
The Adaptive Frontlighting Xenon System (AFX) developed for Volkswagen cars was the first example of glarefree high beam as enhanced adaptive frontlighting functions. As early as in 2010, the series production of Volkswagen models equipped them with the AFX module. The function, called ‘masked high beam’ at VW, became a wellknown term.
Swivelling projector modules – adaptive functions using mechatronics
The core element of the headlamp of the Volkswagen Touran is the centrally located 70mm AFX projector module, generating all main frontlighting functions with one D3S Xenon bulb. The module is equipped with a stepper motor operated triple-layer shutter. Continuously adapting, the shutter creates various shapes of cut-off lines. Complementary projector modules in both headlamps are swivelled and levelled by means of integrated stepper motors. Jointly, they ensure various lighting functions including glarefree high beam. The detected traffic partners are omitted and glare for other drivers is avoided.
BMW: First swivelling LED reflectors in the market
As a pioneer in projector technology since 1986 and a leader in dynamically operated projectors since 2003, BMW initiated the market introduction of dynamic reflectors for adaptive frontlighting in 2013. Automotive Lighting developed these lighting innovations, alongside the first all-LED headlamp to offer dynamic curve light through horizontally rotated reflectors. Adaptive functions using electromechanical actuators
Basically, each headlamp of this BMW option consists of two double reflectors and incorporates such adaptive functions as glarefree high beam, dynamic curve light and static bend light. Both reflectors of one unit are divided into two parts by design elements in the form of horizontal blinds. The reflectors are vertically adjustable by means of stepper motors. Additionally, the outboard reflector is also swivelled horizontally by another stepper motor.
The two reflectors in the bottom of both units jointly provide the full high beam. In the case of oncoming or proceeding traffic, the inboard high beam reflector is switched off. From this moment on, the chambers of the glarefree high beam (outer reflectors) in both headlamps of the car take over the masked high beam distribution. They swivel horizontally by means of stepper motors and, in doing so, they omit the oncoming or proceeding cars. Using vertical stepper motor,
the range of the beam pattern is lifted to a maximum without dazzling other drivers.
By offering mechatronically controlled adaptive reflectors, BMW once again initiated a new innovation in automotive frontlighting technology.
The high-end version of the latest Audi TT (MY2015) is equipped with all-LED headlamps using a low beam projector electronic light module called an ‘e-light’, and reflectors for the adaptive light functions. The light distribution is controlled by sophisticated integrated electronics. The headlamp impresses with its linear ‘matrix’ high beam function and the progressive turn signal function.
Individually addressable LEDs in segmented reflectors
The linear ‘matrix high beam’ is realized by three segmented reflectors. Two of them use one five-chip LED each which generate the glarefree high beam distribution. The third separate reflector unit, sitting inbound close to the bend light reflector, is powered by two single LEDs. One of them is responsible for the additional spot, the other for the side illumination.
All LED chips can be individually activated: Once the camera detects oncoming or proceeding traffic, the information is transmitted to the electronic control unit which controls the relevant LED chips and switches them off in order to avoid dazzling other drivers. When the oncoming car moves closer, the first chips are modulated again. The process moves on as the other drivers pass without any risk from light glare. Mercedes-Benz: ‘Multibeam’ double projector concept
The optimum combination of advantages of the intelligent electronic control and mechatronic actuation embodies the headlamp of Mercedes-Benz CLS (C218 facelift) using two projector modules per headlamp to overlay the light distribution. Referring to driving safety and regarding technological innovation, this headlamp sets new standards. Particular attention is paid to the glarefree high beam function which Mercedes-Benz calls ‘MULTIBEAM LED’.
Milliseconds away
The outboard module ‘LFX’ is the core element of this intelligent frontlighting system. It is powered by one four-chip LED array. Equipped with a stepper motor controlled three-dimensionally defined rotating shutter drum, it generates incrementally adjusted light distribution. This shutter drum is located in the middle of the module between the semiconductor light sources and the carefully shaped lens. This multi-function spot module generates the basic light distributions including flat cut-off line, country road light, motorway
light and the ‘glarefree high beam’ function. Using an additional vertically adjusting stepper motor, it can allow drivers to increase speed and still use the high beam light without dazzling other drivers. The camera provides the information for maximum range enhancement. The integrated horizontal stepper motor is generating a dynamic curve light and supports the adjustment of the beam pattern during adverse weather conditions. This LFX-module is equipped with integrated thermo-management by integrated NTC-elements, a passive heat sink and a motor-driven active ventilator.
The inbound ‘PHB’ module complements the light distribution. This camera controlled module is equipped with a pattern of 24 single LEDs on a rigid board with integrated electronics. A complex, numerically calculated brush-like collimation optic captures the emitted light from the activated chips, bundles and re-orientates the light rays towards the secondary lens which generates the light beam pattern for the road. In a flash, the light distribution adapts precisely to each given traffic situation: The integrated control units calculate the light distribution 100 times per second and the 24 high performance LEDs of the ‘MULTIBEAM LED’ module generate 16 individually controlled high-beam segments. The camera located behind the windscreen detects other traffic and multi-beam segments can be switched off within 10 milliseconds if necessary. When the view ahead is clear, the full light beam is activated again.
Benefits of the glarefree high beam
Carmakers do their best to combine light performance with extremely precise light distribution on the road to ensure night driving is safe experience. Automotive Lighting has developed and provides all the abovementioned systems, including the various combinations of electronic and mechatronic control concepts. n
