requirements for development of brake systems
UN ECE R13-H
mean deceleration, brake distance
cold (6,43 m/s2) /hot (3,86 m/s2) friction brake tests
service braking system
secondary braking system
parking brake system
Electronic failure must not lead to unintentional braking
automatic break war adjustment
important factors for requirements for brake systems
number of brake application during lifetime
fading tests
long hill descend, long duration of braking
High speed fading test
many quick decelerations repeatedly
15 x 0,9*vmax to 90kph
a=0,6*g
Brake Blending
mix of regenerative breaking and friction braking
realized through brake-by-wire
Limitation curves Brake Blending
Power rating
Maximum current
Generator efficiency
Brake blending phases
braking force from both systems, regen can’t supply full decel demand
full regen braking
full friction braking, speed and generator efficiency too low
influences on regen braking
battery state of charge
battery temperature
inverter temperature
function integrated braking system
integrated system
brake-by-wire
pedal or pedal force simulator send signal to electric motor
electric motor compresses fluid in cylinder, brake
failure mode: solenoid valves open, brake force is applied directly from pedal
drum brake function
lower application forces
lower dust emissions and corrosion through housing of disk pads
low drag torque through active returning springs
electromagnetic disk brake function
fully electric
individual wheel control
decoupled from brake pedal
motor controller, motor, rot-gear, trans-gear, caliper
electromagnetical drum brake function
AEB system
Automatic Emergency Braking
brake intervention when vehicle is predicted to hit object
AEB system architecture continental
Sense
Object Detection
Plan
Situation Interpretation
AEB Kinematic Control
Act
EBS Delecration control
Hydraulic control unit
Brake System
Tires & Vehicle
Formula AEB Accuracy
TP: True Positive
TN: True Negative
FP: False Positive
FN: False Negative
Formula AEB Sensitivity
Formula AEB Precision
Comparison False Positive False Negative
False Negative: State is not worse than without assistance, driver error
False Positive: Risk of accident
Legal Framework AEB
UN ECE R152
minimum specification of target function
testing of target function
test for TP
test for FP
test for fault detection
requires documentation
safety concept description
risk analysis documentation
validation plan documentation
mandatory installation for new vehicles
Last changeda year ago
