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It utilises the sensors and actuators of the ABS
system.
ESBS is a software development in the ITT
Mark 20 IE control unit.
Electronic stability brake system - ESBS
The electronic stability brake system improves
the track stability and steerability of braked
vehicles by applying each brake as required.
Understeer
If a vehicle understeers during a braking ope-
ration, this means that the maximum corne-
ring grip of the wheels has been exceeded.
The vehicle will slide towards the outside of
the corner over the front axle.
The ABS control unit recognises this situation
from the circumferential speed of the wheel.
The brake pressure acting on the front axle is
thus reduced in order to increase cornering
grip. The vehicle stabilises itself and follows
the direction in which the vehicle is
steered.
Oversteer
If the vehicle oversteers during a braking ope-
ration, this means that the maximum corne-
ring grip of the rear wheel has been exceeded.
The vehicle breaks away towards the outside
of the corner over the rear axle.
The ABS control unit recognises this situation
from the reduced circumferential speed of the
rear wheels and reduces the braking force
acting on the wheels on the inside of the cor-
ner. The guide forces acting on the inner
wheels are increased and thus stabilised.
SSP207/94
SSP207/95
Brakes application
Yaw moment
Counteracting yaw
moment
A functional fault of the ESBS can neit-
her be diagnosed nor rectified, since the
driving dynamics cannot be reconstr
ucted with workshop equipment.
Brake application
Vehicle movement when
understeer occurs
Vehicle movement when
oversteer occurs
Vehicle vertical axis
