2009 Audi Sportback Concept

(from audi press release)

(2009)Audi Sportback concept

Debut in Detroit: Audi is unveiling the Sportback concept show car at the
2009 North American International Automobile Show. With systematic
refinements to the brand’s characteristic design elements, the five-door
model offers a glimpse at the Audi's future design vocabulary. With its
pronounced coupé-like silhouette and large rear hatch, the 4.95 m long
(16.24 ft), 1.93 m wide (6.33 ft) and only 1.40 m high (4.59 ft) vehicle is boldly
progressive for the luxury class.

The technology of the Audi Sportback concept is markedly futuristic. Power
is provided by the world’s cleanest diesel technology: the 3.0-liter V6 TDI
clean diesel almost completely eliminates nitrogen oxides. This engine already
meets the emissions limits of all 50 U.S. states and the EU6 standard
scheduled to take effect in 2014. And numerous measures to ensure top
efficiency mean that the Audi Sportback concept is expected to achieve
impressive fuel consumption figures of 5.9 liters of diesel per 100 kilometers
(39.87 US mpg).

Driving dynamics in a new guise – the idea

Since its introduction in 2004, the concept of the Sportback has established itself
in the compact class. The success of the A3 Sportback has exceeded even the
expectations of its makers – far more customers choose the four-door model with
the large rear hatch than its three-door sibling.

But it is far more than two additional doors that sets the A3 Sportback apart from
the base model. It is characterized by the sporting elegance of a coupe, the
versatility of a five-door model, sophisticated technology and pronounced
sportiness – driving dynamics in a new guise.

It also offers even more space and variability thanks to a tail end that is a total of
54 millimeters (2.13 in) longer that of the three-door model.

The launch of the first production Sportback marked the second time that Audi
started a new trend in the automobile market. The development of the first Avant
models in the seventies laid the foundation for a new class of automobiles far
beyond the matter-of-fact utility of the classic station wagon. The marked
accentuation of a futuristic and dynamic design, high-quality equipment and
extreme variability have been the distinguishing features of every Audi Avant
from the very beginning.

The Audi Sportback concept show car is now rolling up to the starting line with a
dual mission: As suggested by the name, it symbolizes the Sportback principle in
its purest form in the combination of elegance, sportiness and variability.

And the show car also signals the company's determination not to limit Sportback
versions to the compact segment. As previously indicated by the Audi A1
Sportback concept – the star of the 2008 Paris Motor Show – the brand with the
four rings is going to dramatically expand the number of Sportback models on the
market.

Design

The design of the Audi Sportback concept is characterized by an almost
monolithic clarity and a vast reduction of the number of lines. The roof, shoulder
and sill lines appear to have been drawn with a single stroke. The window strip of
the coupé with its four frameless doors was kept pronouncedly flat. Viewed from
the side, the softly contoured wheel wells over the 10-spoke, 21-inch wheels
reinforce the impression of the precisely defined surfaces of the body.

One feature familiar from the two-door Audi A5 coupé is even more boldly
accentuated here: The markedly horizontal shoulder area emphasizes the
orientation of the vehicle body to the road. This effect is further reinforced at the
front and rear by the broad, flat LED light units. The shape of the almost fragile-
looking side mirrors is inspired by the upturned tips – the “winglets” – of modern
jet wings.

The show car also offers a new interpretation of the single-frame grille. The
decision not to use vertical struts and the low overall height emphasize the sporty
basic proportions of the vehicle front. Also particularly striking is the modified
outer contour of the single-frame grille as also featured on the A1 Sportback show
car. The flattened top edges lower the visual center of gravity and provide a
striking look for the front end.

The aerodynamically designed air intakes under the headlights function as air
deflectors which guide the required cooling air precisely into an intake duct. They
have the stylistic effect of accentuating the impression of width.

The tail of the show car is also evidently related to the A5 coupé. The high top
edge of the rear hatch gives rise to a strikingly clear surface below the rear lights.

The low separating edge and the horizontal lines – another characteristic feature –
underscore the width and therefore the sporty nature of the Audi Sportback
concept. The four tailpipes integrated into the body and an air deflector in the
diffuser insert are cues borrowed from the sportscar sector.

The interior design is tidy and downright purist yet elegant at the same time. The
large glass roof underscores the width and feeling of spaciousness. In the driver-
oriented cockpit, the air vents, instrument cluster and retracting MMI monitor are
outlined by a filigree aluminum border.

As with the exterior, the interior is characterized by the emphasis on horizontal
lines and large surfaces. Especially the wide center console – stretching from the
dashboard to the back – seems to be a pure expression of function.

The flat display of the MMI system is realized as a retractable system in the show
car. When the ignition is activated, it extends horizontally from a slot above the
central air register before moving in an elegant arc into a vertical, easy-to-read
position.

The high quality of the materials and manufacturing-level fit and finish are
obvious when looking around the interior of the Audi Sportback concept and
when touching the surfaces. The interior trim is almost completely in leather:
from the headlining, dashboard, doors and the entire seat upholstery all the way
through to the trunk, with the leather stitching underscoring the vehicle’s design
language. The large wood trim strips on the instrument panel, center console and
doors are machined from oak blockboard and sport a delicate horizontal pattern of
light and dark lines.

With its surfaces of piano lacquer and brushed aluminum, the MMI control unit
also adds to the exceptional exclusivity of the interior. The attention to detail even
extends to the door opener: Its shape is a nearly perfect reflection of the
distinctive lines of the small rear side window – giving the interior and exterior
formal unity.

Four sporty seats await the driver and passengers. The diamond-shaped stitching
of the leather surface is reminiscent of a classic GT tradition. Shoulder, head and
leg room are reminiscent of a premium-class touring car. With a volume of
500 liters (17.66 cubic feet), the trunk is generously sized and is also appointed
with high-quality materials.

Drivetrain

The developers at Audi chose the world’s cleanest diesel technology as the unit
best befitting the Audi Sportback concept show car. The six-cylinder 3.0 TDI
clean diesel is equipped with a system for the effective reduction of nitrogen
oxides. The diesel engine development engineers at Audi have combined an entire
package of innovative measures for this latest TDI generation: The piezo common
rail system with an injection pressure of 2,000 bar, highly efficient exhaust gas
recirculation and optimized turbocharging result in significantly reduced raw
engine emissions. One of the highlights are the combustion chamber sensors that
enable even more precise regulation of the combustion processes in the engine –
this is the first time that such sensors have been installed on any engine in the
world, marking yet another Audi innovation.

The status of the new-generation TDI as the definitive clean-running, high-tech
diesel is sealed by the downstream exhaust emission control system, which
reduces emissions by up to 90 percent. The system uses AdBlue, a biologically
degradable, waterborne additive that is injected in small amounts upstream of the
DeNOx catalytic converter. In addition to the catalytic converter, the exhaust
emission control system comprises the metering module, the AdBlue tank and
heated lines, as well as an extensive system of sensors. The additional oxidizing
catalytic converter and the highly efficient, regulated diesel particulate filter round
off the comprehensive emission control system.

Thanks to their extremely low emission levels, these modern direct-injection
diesel engines can be put into service anywhere in the world, even in the U.S.
state of California, which has the world’s most stringent emissions limits.
Compared with the fleet average of the gasoline engines typically found in the
U.S., the TDI boasts a fuel-efficiency advantage of up to 40 percent. The diesel
technology thus makes a greater contribution than any other type of engine to
reducing the consumption of fossil fuels. Audi will offer this engine in the U.S.
and Europe beginning in 2009.

As in the U.S. version of the Audi Q7 3.0 TDI, the V6 also produces 165 kW
(225 hp) and 550 Nm (405.66 lb-ft) of torque in the Audi Sportback concept.
Power is transferred to the wheels via Audi’s most modern transmission: the new
7-speed tiptronic. The quattro permanent all-wheel-drive system ensures that the
torque generated by the powerful TDI is also converted effectively into propulsion
and dynamism under any conditions.

Weighing just 1,800 kilograms (3,968.32 lb) and with a drag coefficient of 0.30,
the coupe will accelerate from 0 – 100 km/h (62.14 mph) in less than seven
seconds and reach a top speed of 245 km/h (152.24 mph).

The Audi Sportback concept’s average fuel economy according to the European
ECE standard is only 5.9 liters of diesel per 100 kilometers (39.87 US mpg), and
its CO2 emissions no more than 156 g/km (251.06 g/mile). These sensationally
low figures for a large model have been achieved by extensive efficiency-
optimizing measures.

For example, this model’s electromechanical power steering only consumes
energy when the steering is turned, not when driving in a straight line.

The TDI engine features an innovative temperature management system. When
the engine is warming up, part of the coolant flow is diverted – another way to
improve efficiency, since it helps the engine to warm up quicker. This means
significant practical savings, because many journeys are fairly short. The fuel
pump also runs only when there is a demand for fuel, and therefore uses less
energy.

The 7-speed S tronic transmission is a very efficient unit with a wide spread of
gear ratios. For the first time, it has been equipped with transmission oil heating,
so that it reaches its intended operating temperature much earlier and therefore has
a lower level of internal friction.

When coasting, the Audi Sportback concept – like the Audi A4 and Audi Q5
production models – recuperates energy. This boosts the output of the alternator
and is used to charge the battery. This energy, which in effect costs nothing to
recover, is fed back into the vehicle’s electrical system when needed. An
automatic start-stop system shuts the TDI engine down to save energy, for
instance when waiting at a traffic signal.

And when it is on the move, tires optimized for low roll resistance cut fuel
consumption significantly without incurring any disadvantages in the performance
area.

Driving dynamics

The Audi Sportback concept show car took the basic architecture and many
components of its suspension from the brand’s latest and most successful model
family: the very dynamic A4/A5 model series. The dynamic suspension sets
standards here, as well, combining precision and dynamism with high stability
and superior poise. The suspension mountings, steering, wheels and brakes have
been developed for top performance and numerous aluminum components are
used to keep unsprung masses to a minimum.

The new five-link front suspension makes a major contribution to the car’s
dynamic character. By moving the differential further forward and the clutch
further back, the design engineers were able to reposition the front axle 154
millimeters (6.06 inches) further forward. The result is an optimal distribution of
weight between the front and rear axles.

The front suspension is made up of five links per wheel – a support link and a
control arm at the bottom and two control arms at the top. The fifth link – the
track rod – connects the steering box and the pivot bearing. All these links are
made of forged aluminum, ensuring low unsprung masses, ultra-precise wheel
control and a high level of crash safety. The anti-roll bar fabricated from a high-
strength tube saves additional weight. The backbone of the rear axle is a subframe
with high flexural and torsional rigidity.

If sporty handling is to be combined with a high standard of ride comfort, the
unsprung masses must be kept as low as possible. Audi has pursued this approach
for all the rear-axle components. The upper control arms and the track rods are of
forged aluminum. Their high rigidity ensures that toe and camber angles change
very little when dynamic forces act on the wheels.

The CDC (continuous damping control) shock absorbers, similar to those that
Audi already uses on the luxury Q7 SUV with air suspension, are twin-tube, gas-
filled hydraulic units with an additional external valve and connecting pipe. Their
operation can be continuously varied.

An electromagnetically energized, proportional-action valve regulates the flow of
hydraulic fluid between the inner and outer damper tubes. A smaller flow cross-
section makes the damping characteristic firmer, a larger one makes it softer.

The control unit applies adaptive operating characteristics within the mode the
driver has chosen via Audi drive select. It adapts to match the driver’s driving
style and the road conditions. Even from the comfort mode, the shock absorbers
can be switched in an instant to a firm setting if desired, though not to the absolute
limit. They are fitted in conjunction with sports suspension springs, which still
provide a good level of ride comfort, even off-road.

The control unit selects the optimum damping force for the current driving
situation, for instance firmer damping to prevent body roll and pitch when
cornering fast or braking, or lower damping force where the surface under the
wheels is hard and uneven.

The show car marks the first time that Audi has used electromechanical steering
in a car with a longitudinal engine. Its primary advantage is that, unlike
conventional power steering systems, it only consumes energy when actually
steering. On average, this means a fuel saving of 0.2 liters per 100 kilometers,
depending on driving conditions.

The electromechanical steering of the Audi Sportback concept also enables the
coupling with the parking steering assistant for fully automatic steering when
parallel parking.

The Audi Sportback concept is equipped with ceramic brakes on all four wheels
for effective deceleration even under the most demanding conditions. Compared
with conventional steel disks, ceramic brakes not only last four times longer, up to
300,000 kilometers (186,411 miles), but also offer high resistance to fading. The
significant reduction in weight also leads to advantages in terms of comfort and
handling, thanks to reduced unsprung masses.

On the front axle, 380-millimeter (14.96-inch) ceramic disks are fitted in
combination with 21-inch wheels. The rear disks have a diameter of 356
millimeters (14.02 inches). The elaborate cooling duct geometry of the ventilated
brake disks ensures optimal cooling of the brake disks. Firm grip on the brake
disk is guaranteed at the front by 6-piston monobloc aluminum brake calipers, and
at the rear by floating-caliper brakes.