ESP

ESP with dynamic steering

improved through simultaneous
corrective braking and steering
inputs. This is especially true at
speeds greater than 60 mph, due to
the dynamic steering system being able
to take advantage of its quick reaction times.
Basic setting:

> Check the calibration of the steering angle sensor.

> Deviation between measured value and actual steering wheel angle .s 0.3°
> Steering angle sensor cannot be programmed 7 Service information: TSB
2043629

> Align wheels straight ahead (wheel alignment).
> Perform the dynamic steering basic setting.

RS 7, RS wet fade brake compensation (VVFC)

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Presentation title

Date

RS 7 1 RS wet fade brake compensation (VVFC)
Function
In wet weather conditions, a thin film of water can form on the friction surface of
the brake disc, which initially has to be rubbed away by means of the first braking
action. This can lead to an impaired level of comfort due to the sensation that extra
braking force is required. This situation is unavoidable for physical reasons.
In order to minimize the influence of the principles described above on the pedal
sensation and to make the initial braking action more comfortable, in the Audi RS 7
the function "wet brake fade
and RB
compensation" (WFC) has been introduced.
WFC is activated when the wipers are actuated either permanently or in interval
mode, or if the rain sensor is active, when the wiper is actually in action. WFC
remains active for a further three minutes following the last actuation of the wiper,
after which time the function is deactivated. The WFC is also activated through
actuation of the wiper washing mechanism, and remains active for three minutes.

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AUDI AG

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Presentation title

Date

RS 7 1 RS wet fade brake compensation (VVFC)
Function

> WFC compares the brake pressure applied by the driver via the brake pedal with the
delay that then follows. If the detected delay is considerably less than would be
expected based on the hydraulic brake pressure, WFC contributes to active braking
via the ABS unit. The time from the first actuation of the pedal until active braking
of the WFC is approx. 0.5 seconds. Via the ABS unit, the brakes are then applied to a
deceleration value that is appropriate for the initiated hydraulic brake pressure and
therefore the driver's requirements.

> The driver then senses that the path of the brake pedal becomes longer for a brief
period, and a pulsing of the brake pedal occurs that is similar to ABS braking. The
additional braking via the WFC can be noticeably sensed by the driver depending on
the situation.

»

For drivers with no experience of the mechanism of action of the WFC, an
intervention by the WFC can initially feel strange, although the braking itself is
made more comfortable by the WFC.

Carbon fiber-reinforced plastic in the new RS (45)

AUDI AG

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Carbon fiber-reinforced plastic in the new RS (45)
Agenda
•

II
II
•

CFRP -

Basic information about carbon-fibre-reinforced plastic

CFRP -

Carbon-fibre-reinforced plastic in the new Audi RS/45

Support strategy for CFRP structural repairs

CFRP at service partners

AUDI AG

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CFRP - Information about carbon fiber-reinforced plastic

AUDI AG

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CFRP - Information about carbon fiber-reinforced plastic
Composites

> Combination of two or more components
> Has the advantages of the individual components
7 Properties that cannot be achieved by a single component

> Depending on the geometry of the material combination

> Particle composite

> Multilayer composite

> Fiber composite

AUDI AG

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CFRP - Information about carbon fiber-reinforced plastic
Fiber composites
Fiber-reinforced plastics (FRP), or fiber-reinforced polymers, are a subgroup of composite
materials.
Composite materials are materials that combine various different components.
This combination of components makes it possible to achieve properties that cannot
be produced using a single component alone.

Reinforcing fibers

~ ------··

AUDI AG

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CFRP - Information about carbon fiber-reinforced plastic
Reinforcing fibers
Natural fibers

> Wool, silk, cotton, flax, hemp
Organic fibers

> Polyethylen, Polyester, aramid, carbon
Inorganic fibers

> Glass, basalt, quartz
Metal fibres

> Steel, aluminum, copper, nickel

Comparison: Carbon fiber, human hair

AUDI AG

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CFRP - Information about carbon fiber-reinforced plastic
Reinforcing fibers
Task of the fibres:

> Load transfer

t

t

I

I

> Absorption of elongation
> Determination of mechanical properties
Rigidity
Strength
Thermal expansion
Only tensile forces, no compressive forces

High strength
Low elasticity

Fiber orientation 0°

Fiber orientation 90°
Multiaxial fabric
(90°/±45°/0°)

Fiber orientation +45°

Fiber orientation -45°

Linen weave

Low strength
High elasticity

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CFRP - Information about carbon fiber-reinforced plastic
Matrix
Task of the matrix

> Prevents kinking of the fibers (for added strength under compressive stress)

> Interlocking of the individual fibers
> Determines the mechanical properties (rigidity, strength, thermal expansion)
> Protection of the fibers
> Fixing of the fibers (shape and stability)
Material of the matrix

> Epoxy resin, polyester resin, phenolic resin
Matrix~

•••••

AUDI AG

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CFRP - Information about carbon fiber-reinforced plastic
Fiber composites
Designer composite - with variable properties ranging from high strength to high
rigidity

Influenced by:

> Fiber - resin combination
> Fiber orientation and layer construction
> Local patches and reinforcements
> Manufacturing process

AUDI AG

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CFRP - Information about carbon fiber-reinforced plastic
Comparison of CFRP weight
Component weight ratios when performing the same function

100%

-40%
75%

Audi RB/45
50%

25%

- 55%
-60%

AUDI AG

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CFRP - Information about carbon fiber-reinforced plastic
Comparison of strength/rigidity
Low weight

> Due to low density of materials
> Due to optimum use of materials
High strength/rigidity
Density pin g/cm 3

0

1

2

3

4

5

6

7

8

9

Wood
CFRP
Magnesium
GFRP
Aluminium
Steel
Strength in MPa

0

500

1000

1500

2000

2500

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CFRP - Information about carbon fiber-reinforced plastic
Resin transfer molding (RTM) production process
10-60 seconds
5-10 minutes, 80-120°(

Hardener

Resin

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CFRP in the new RS (45)

AUDI AG

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CFRP in the new RS (45)
CFRP at Audi
Visible CFRP

> Non-crimp fabric for the top layer
> Clear coat as surface protection

Class A CFRP

> Colour-painted
> Mostly used for exterior add-on parts

CFRP structure

> New in the RB (type 45)

AUDI AG

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CFRP in the new RS (45)
\Nhy carbon fiber-reinforced polymers?

> Low weight

> High strength/ rigidity
> Low thermal expansion
> High corrosion resistance
> Broad scope for design
> Good aging properties/ fatigue strength
> High energy absorption capacity (crash performance)

AUDI AG

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CFRP in the new RS (45)
Multi-material Audi space frame (ASF)

~

~
~
~

MSS (Modular Sportscar System) platform
13 percent carbon fibre reinforced polymer (CFRP) in the body structure
The body structure is 10 kilogrammes lighter than that of the previous model
Static torsional rigidity is 40 percent higher than that of the previous model

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CFRP in the new RS (45)
CFRP parts

upper B-pillar

rear bulkhead

outer B-pillar

tunnel
outer B-pillar

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CFRP in the new RS (45)
Joining techniques

> 89 metres of MIG weld seams
> 270 semi-tubular punch rivets
> 207 pop rivets
> 241 metric screws
> 270 self-tapping screws

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Support strategy for CFRP structural repairs

AUDI AG

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Support strategy for CFRP structural repairs
\Nhy have a support strategy?

New requirements for diagnostic and repair process

> New process for diagnostic and repair of accident damage
> Special workshop equipment is required
> Damage diagnostic by ultrasound measurement
> Experience is required for the various works operations
Ensuring highest quality repairs

> Centralised development of knowledge and expertise

> Achieving process reliability

»

AUDI is using CFRP in its vehicle structure for the first time, so we must work
together to become familiar with this new technology and continue to adapt our
support strategy accordingly.

AUDI AG

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Support strategy for CFRP structural repairs
CFRP support points Europe

~

Projected CFRP diagnoses during start-up pha'S e
~

Germany and Europe (exluding UK): flying technicians of AUDI AG

~

UK: diagnostic technicians of importer

CFRP repair centre in UK
= 49 diagnoses (2015-2017)

CFRP repair centre of AUDI AG
= 138 diagnoses (2015-2017)

I Projection based on damage events concerning the previous model I

AUDI AG

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Support strategy for CFRP structural repairs
Process

RS partners
I

l

CFRP structural damage is

visible

Visual

~

- inspection ~

CFRP repair centre
(importer I AUDI AG)
Repair
(CFRP and aluminium
components)

l

CFRP structural da~~ge