Task
The Active Brake Assist controller unit detects obstacles in front of the vehicle and warns the driver about possible collisions. The Active Brake Assist controller unit differentiates, in this connection, between vehicles in front, crossing traffic and bike riders. If the Active Brake Assist controller unit detects a collision risk, it initiates an autonomous brake application.
The Active Brake Assist controller unit is connected to the network architecture of the vehicle.
For the implementation of the functions, the Active Brake Assist controller unit processes among other things the following information:
Terminal status of terminal 15
Operating condition for engine/drivetrain
Wheel speed and wheel rotation direction
Acceleration/yaw rate
Electronic Stability Program (ESP®) status
Steering wheel angle and steering wheel velocity
Accelerator pedal position
Brake pedal position
Driver's requests via menu settings
Depending on the national version, the Active Brake Assist controller unit also processes object information of the multifunction camera behind the windshield.
The Active Brake Assist controller unit processes this information and transmits among other things the following requests:
Warning output requests
Requirements for initiating PRE-SAFE® measures
Increase braking torque request
Request to reduce engine torque
Structure
The Active Brake Assistant controller unit contains the following assembly parts:
Radar sensor
Control unit
Properties of the radar sensor:
Detection range:
40 m for a detection angle of 45°
160 m for a detection angle of 7.5°
Operating frequency: 77 GHz
The radar sensor works according to the Pulse-Doppler principle for the independent measurement of distance and speed.
The Active Brake Assistant controller unit must be newly adjusted after exchange (e. g. after an accident repair) using the integrated "service adjustment mode".