2005 SSANGYONG RODIUS tires

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RODIUS 2005.07
4892-01
ESP SYSTEM
3. ESP SYSTEM DESCRIPTION
1) Principle of ESP
ESP (Electronic Stability Program) recognizes critical driving conditions, such as panic
reactions in dangerous 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 wheel 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).
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 unde
r
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
ESP controls during under steering
The ESP system recognizes the directional
angle with the steering wheel angle senso
r
and senses the slipping route that occurs
reversely against the vehicle cornering
direction during understeering with the yaw
rate sensor and the lateral sensor. Then the
ESP system applies the brake at the rea
r
inner wheel to compensate the yaw moment
value.
In this way, the vehicle does not lose its
driving direction and the driver can steer the
vehicle as driver intends.

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ESP SYSTEM
RODIUS 2005.07
4892-01
Over steeringOversteering is when the steering wheel is
steered to a certain angle during driving and
the rear tires slip outward losing traction.
When compared with under steering
vehicles, the controlling of the vehicle is
difficult during cornering and the vehicle can
spin due to rear wheel moment when the
rear tires lose traction and the vehicle speed
increases.
ESP controls during oversteering
The ESP system recognizes the directional
angle with the steering wheel angle senso
r
and senses the slipping route that occurs
towards the vehicle cornering direction
during oversteering with the yaw rate senso
r
and the lateral sensor. Then the ESP system
applies the brake at the front outer wheel to
compensate the yaw moment value.
In this way, the vehicle does not lose its
driving direction and the driver can steer the
vehicle as he or she intends.
2) ESP Control
The ESP system includes the ABS/EBD and ASR systems allowing the system to be able to
operate depending to the vehicle driving conditions. For example, when the brakes are applied
during cornering at the speed of 100 km/h, the ABS system will operate at the same time the
ASR or ABD systems operate to reduce the power from the slipping wheel. And when yaw rate
sensor detects the rate exceeding 4¡Æ/seconds, the ESP system is activated to apply the
brake force to the corresponding wheel to compensate the yaw moment with the vehicle
stability control function. When various systems operate simultaneously under a certain
situation, there may be vehicle control problems due to internal malfunction of a system o
r
simultaneous operations. In order to compensate to this problem, the ESP system sets the
priority among systems. The system operates in the order of TCS (ASR or ABD), ESP and
ABS. The order may be changed depending on the vehicle driving situations and driving
conditions. As the single-track vehicle model used for the calculations is only valid for a vehicle
moving forward, ESP intervention never takes place during backup.

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RODIUS 2005.07
4892-01
ABS SYSTEM
2. GENERAL INFORMATION
The aim of the ABS is to mmaintain steerability and driving stability and to take the burden off
the driver. If the stopping distance is shorter on some road surfaces (carriageway conditions),
this is a gift of physics and not a development aim.
ABS is a device which senses that one or more of the wheels are locking up during braking. It
monitors the rotational speeds of the wheels and reduces hydraulic pressure to any wheel it
senses locking up. It is controlled by both mechanical and electronic components. When you
apply the brakes, the ABS will regulate the flow of brake fluid being delivered to the brake
calipers. By the use of electronic computers, the brakes rapidly alternate (at a rate of 30 times
per second) from full pressure to full release.
1) DRIVING PHYSICS
To give you a better understanding of the tasks and functions of ABS, we will first look at the
physics principles.
(1) The Stopping Distance
The stopping distance depends on the vehicle weight and initial speed when braking starts.
This also applies for vehicle with ABS, where ABS always tries to set an optimum brake force
on each wheel. As great forces are exerted between the tires and the carriageway when
braking, even with ABS the wheels may scream and rubber is left on the road. With an
ABS
skid mark one may be able to clearly recognize the tire profile. The skid mark of an ABS vehicle
does not however leave any hint of the speed of the vehicle in the case of an accident, as it can
only be clearly drawn at the start of braking.
(2) Brake Force on a Wheel
The maximum possible brake force on a wheel depends on the wheel load and the adhesion
coefficient between tire and carriageway. With a low adhesion coefficient the brake force, which
can be obtained is very low. You are bound to know the result already from driving on winte
r
roads. With a high adhesion coefficient on a dry road, the brake force, which can be obtained,
is considerably higher. The brake force, which can be obtained, can be calculated from below
formula:

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WHEEL
RODIUS 2005.07
4710-09
2. TIRE’S ABNORMAL PHENOMENA
1) Standing Wave
2) Hydroplaning
During running the rotating tire repeats
deformation and restoring movement
generated in tread. But when the wheel
rotating speed reaches high, the next
deformation applied to tire before restoring
last deformation so the trembling wave
appears in the tread portion. The lower the
tire pressure the severe the trembling wave
appears during the high speed.
The condition of driving a vehicle fast on the
road surface covered with water can cause
tires to fail to rotate with a good contact on
the surface, so results in remaining them a
float. This is so-called hydroplaning. It
causes brake failure, lower tractive force
and losing the steering performance so it is
very vulnerable condition.

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RODIUS 2005.07
4710-09
WHEEL
3. WHEEL ALIGNMENT
The first responsibility of engineering is to design safe steering and suspension systems. Each
component must be strong enough to with stand and absorb extreme punishment.
Both the steering system and the front and the rear suspension must function geometrically
with the body mass.
The steering and suspension systems require that the front wheels self-return and that the tire
rolling effort and the road friction be held to a negligible force in order to allow the customer to
direct the vehicle with the least effort and the most comfort.
A complete wheel alignment check should include measurements of the rear toe and camber.
1) Toe-in
2) Camber
Toe-in is the turning in of the tires, while toe-
out is the turning out of the tires from the
geometric centerline or thrust line. The toe
ensures parallel rolling of the wheels.
The toe serves to offset the small deflections
of the wheel support system which occu
r
when the vehicle is rolling forward.
The specified toe angle is the setting which
achieves-degrees “0°” of toe when the
vehicle is moving.
Incorrect toe-in or toe-out will cause tire
wear and reduced fuel economy. As the
individual steering and suspension
components wear from vehicle mileage,
additional toe will be needed to compensate
for the wear. Always correct the toe
dimension last.
Camber is the tilting of the top of the tire
from the vertical when viewed from the front
of the vehicle. When the tires tilt outward,
the camber is positive. When the tires tilt
inward, the camber is negative. The cambe
r
angle is measured in degrees from the
vertical. Camber influnces both directional
control and tire wear.
If the vehicle has too much positive camber,
the outside shoulder of the tire will wear. I
f
the vehicle has too much negative camber,
the inside shoulder of the tire will wear.
Camber is measured in degrees and is not
adjustable.

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CLUSTER
RODIUS 2005.07
8010-10
2) Speedometer
The speedometer indicates the vehicle speed by calculating the signals from the rear right
wheel speed sensor through ABS or ESP unit.
If the speedometer pointer vibrates, stands at a certain range or sounds abnormal noise, there
could be defectives in speedometer. However, these symptoms also could be appeared when
the tire has uneven wear, different tire inflation pressures or different tire specifications.
Perform the speedometer test regarding the tolerance as described. However, it is not simila
r
simple work in field due to lack of measuring conditions such as test equipment and
preciseness.
Check the allowable tolerance of the speedometer and operations of the trip odometer by
using a tester.
Check if the speedometer pointer is shaking and the abnormal noise sounds.
Eliminate the hysteresis by tapping the speedometer. 1.
2.
3.
The allowable tolerance increases when the tires are worn or the tire pressure is out of
specified range. -