Principle Of Esp - SSANGYONG Actyon 2012.12 Manual

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3. PRINCIPLE OF ESP

1) Understeer & Oversteer Control
situations, and stabilizes the vehicle by wheel-individual braking and engine control intervention with no
need for actuating the brake.
This system is developed to help the driver avoid the danger of losing the control of the vehicle
stability due to under-steering or over-steering during cornering.
The yaw rate sensor, lateral sensor and longitudinal sensor in the sensor cluster and the steering angle
sensor under the steering column detect the spin present at any wheels during over-steering, under-
steering or cornering.
The ESP ECU controls against over-steering or under-steering during cornering by controlling the
vehicle stability using the input values from the sensors and applying the brakes independently to the
corresponding wheels.
The system also controls during cornering by detecting the moment right before the spin and
automatically limiting the engine output (coupled with the ASR system).
(1) Under steering
Understeering is when the steering wheel is steered to a certain angle during driving and the front
tires slip toward the reverse direction of the desired direction.
Generally, vehicles are designed to have under steering.
The vehicle can return back to inside of cornering line when the steering wheel is steered toward the
inside even when the vehicle front is slipped outward.
As the centrifugal force increases, the tires can easily lose the traction and the vehicle tends to slip
outward when the curve angle gets bigger and the speed increases.
Under Steering