Function Of Adaptive Highbeam Assist - GF82.10-P-3091GWM
Model 463 (except 463.342)
as of model year 2019
with code L57 (IHC Light)
Function requirements, general
- No overvoltage or undervoltage
- Transport mode not active
- "Engine running" or "drive train operational" signal on
- Exterior lights switch (S1) in position "AUTO"
Low beams actuation is active during high beams actuation.
- Combination switch (S4) in "High beams" position
The CDI control unit (N3/9) (diesel engine) or the ME-SFI control unit (N3/10) (gasoline engine) sends the "engine running" or "drive train operational" signal via the drive train CAN (CAN C1), powertrain control unit (N127), chassis FlexRay (Flex E), electronic ignition lock control unit (N73) and interior CAN (CAN B) to the front SAM control unit (N10/6).
The steering column tube module control unit (N80) reads in the switch position of the combination switch directly and sends it to the front SAM control unit via the chassis FlexRay, electronic ignition lock control unit and interior CAN.
The front SAM control unit reads in the status of the exterior lights switch directly.
As the master control unit for the exterior lights, the front SAM control unit reads in the function requirements, evaluates them and issues the release for the Adaptive Highbeam Assist function.
The front SAM control unit sends the enable over the interior CAN, electronic ignition lock control unit and the suspension FlexRay to the mono multifunction camera (A40/11).
The multifunction camera is the master control unit for the Adaptive High Beam Assist.
Function sequence for Adaptive Highbeam Assist
The multifunction camera detects the traffic and environment situation in front of the vehicle and evaluates this. Optimal illumination of the roadway is guaranteed by modifying the light distribution without dazzling other road users. The multifunction camera uses the brightness, shape, structure, color, where applicable, and motion of detected objects to differentiate between preceding or oncoming road users, street lighting, signs or other parts of the environment. The picture recognition module integrated into the multifunction camera judges the distance, e.g. to other road users, evaluates the outside brightness level of the vehicle environment and recognizes extreme weather conditions (e.g. thick fog, heavy snowfall) or tunnels.
The multifunction camera evaluates the following information to implement the function, among other things:
- Steering angle
- Vehicle speed
- Yaw behavior
The steering column tube module control unit directly reads in the data from the steering wheel angle sensor (N49) and calculates the steering angle.
The steering column tube module control unit sends information on the steering angle over the suspension FlexRay to the mono multifunction camera.
The vehicle speed is calculated on the basis of the wheel speeds.
The Electronic Stability Program control unit (N30/4) sends information on the wheel speeds over the suspension FlexRay to the mono multifunction camera.
The yaw behavior of the vehicle is recorded by the acceleration sensor integrated in the Supplemental Restraint System control unit (N2/10). The Supplemental Restraint System control unit sends information about the vehicle's yaw characteristics over the vehicle dynamics CAN (CAN H), Electronic Stability Program control unit and the suspension FlexRay to the mono multifunction camera.
A differentiation is made between the following Adaptive High Beam Assist functional states:
- Optical headlamp range adjustment (as of approx. v = 25 km/h)
The headlamp range of the low beam is automatically adapted to the distance to other road users.
- Automatic high beams (as of approx. v = 30 km/h)
The high beams are activated if no other road user is detected.
- Partial high beams (from approx. v = 30 km/h)
The partial high beam places road users in the low beam section of the light cone thereby omitting them from the high beam.
Optical headlamp range adjustment (as of approx. v = 25 km/h)
The multifunction camera evaluates the traffic and environment situation of the vehicle and activates the optical headlamp range adjustment function depending on the distance of the vehicle from other road users and the road geometry (height differences, angle).
The mono multifunction camera sends information about the vehicle's traffic and environment situation along with an "Optical headlamp range control" request over the suspension FlexRay, electronic ignition lock control unit and the peripherals CAN to the left headlamp control unit (E1n9).
The left headlamp control unit synchronizes the right headlamp control unit (E2n9) over the peripherals CAN and actuates the left headlamp range control actuator motor (E1m1) in the left front lamp unit (E1) directly.
The right headlamp control unit actuates the right headlamp range adjustment actuator motor (E2m1) in the right front lamp unit (E2) directly.
The low beam light cones are moved upwards, thereby providing better road illumination without dazzling other road users. The light cone of the headlamps varies between s = 65 m (standard lighting) and s = 300 m.
Automatic high beams (as of approx. v = 30 km/h)
If no other road users are detected as the speed increases, the multifunction camera activates the automatic high beams function.
The mono multifunction camera sends the "high beam ON" request over the suspension FlexRay, electronic ignition lock control unit and the peripherals CAN to the left headlamp control unit.
The activated function is visually indicated to the driver. To do so, the front SAM control unit sends the "high beam ON" request over the interior CAN, electronic ignition lock control unit and the user interface CAN (CAN HMI) to the instrument cluster (A1), which then actuates the high beam control message.
The left headlamp control unit evaluates all of the relevant information and transmits the "High beams light distribution" request via the peripherals CAN to the left front lamp unit LED matrix control unit (E1n11) and the right front lamp unit LED matrix control unit (E2n11). The left front lamp unit LED matrix control unit then actuates the left front adaptive high beam (E1e24) accordingly. The right front lamp unit LED matrix control unit actuates the right front adaptive high beam (E2e24) accordingly.
On roads with street lamps positioned regularly, the automatic high beams are deactivated.
Partial high beams (from approx. v = 30 km/h)
If other road users are detected while the automatic high beams function is active, the multifunction camera activates the partial high beam function. The activated function is visually indicated to the driver. To do so, the front SAM control unit sends the "high beam ON" status over the interior CAN, electronic ignition lock control unit and the user interface CAN to the instrument cluster, which then actuates the high beam control message.
Schematic diagram of partial high beam light distribution
The mono multifunction camera sends information about the detected object and the "Light output adjustment" and "Rotation angle adjustment" requests over the suspension FlexRay, electronic ignition lock control unit and the peripherals CAN to the left headlamp control unit.
The left headlamp control unit evaluates all of the relevant information and transmits the "Increase light output" request and the relevant object data via the peripherals CAN to the front lamp unit LED matrix control units. The front lamp unit LED matrix control units then increase the light output of the adaptive high beams and modify the light distribution so that the preceding or oncoming objects are blocked out of the high beam light cone and therefore not dazzled.
Adaptive High Beam Assist limits:
In tight curves, the multifunction camera may not recognize oncoming vehicles or only do so very late due to the detection angle (α = 35°).
On streets with structural separation (e.g. guardrails on freeways) the headlamps of oncoming vehicles are often concealed. These vehicles cannot be recognized by the multifunction camera.
Due to the geometry of the structural separation and the location of the headlamps on cars, the drivers of the oncoming cars are not dazzled. Truck drivers, however, may be dazzled due to the high seat position. The clearance lamps on trucks are not sufficient for recognition.
When driving over hills, oncoming vehicles are not recognized until late whereupon the high beams are also switched off later. In this situation, however, the driver of the oncoming vehicle is also dazzled by the low beams.
The maximum range of the multifunction camera in poor light is approx. s = 500 m, and in good light it is approx. s = 800 m. In the event of reduced visibility (e.g. due to snow, fog, rain), detection performance may also be affected.
When illuminating large, highly reflective areas (e.g. traffic signs) the power of the headlamps is reduced at less than a specific distance away in order to minimize any self-dazzling effect.
In the event of restricted multifunction camera visibility (e.g. due to fogging or icing), the Adaptive Highbeam Assist function is deactivated.
With bright lights that appear suddenly (e.g. street lamps, traffic lights, illumination of lots), the high beams are deactivated.
Some reflectors cannot be clearly differentiated by road users (e.g. motorcyclists). The high beams are deactivated because of the danger of dazzling other road users.
| Function schematic for Adaptive High Beam Assist | PE82.10-P-2066-97ZGA | ||
| Overview of exterior lights system components | GF82.10-P-9998GW |