Lamborghini has today
offered its take on the future of the high performance
sports car with a concept "technology demonstrator" that
features lightweight construction thanks to the
widespread use of carbon-fiber technology and which
means the "Sesto Elemento", as it has been duubbed, has
an overall kerb weight of just 999 kilograms (2,202 lb)
– including V10 power unit and permanent all-wheel
drive. This makes the Sesto Elemento a unique
demonstration by Lamborghini. The brand says that it
incorporates carbon-fiber technologies that are being
used here for the first time in an automotive
application. As a 100 percent subsidiary of Audi AG, the
Italian carmaker also benefits from the expertise of the
German manufacturer when it comes to lightweight
construction.
With the output of 570 hp from the Gallardo LP570-4
Superleggera-sourced engine that means the Sesto
Elemento offers a power-to-weight ratio of only 1.75
kilograms per hp and a claimed 0 to 100 km/h (0-62 mph)
acceleration of 2.5 seconds. At the same time, fuel
consumption also drops because of the lightweight
engineering applied throughout.
The name of this technology demonstrator is derived from
the periodic table, where carbon is classified as the
sixth element. Thus, the "Sesto Elemento" demonstrates
the expertise of Lamborghini in carbon-fiber reinforced
plastics (CFRP) technology. The sports car brand from
Sant’Agata Bolognese is the only vehicle manufacturer in
the world to have mastered the complete CFRP process
across a range of technologies, from 3D design through
simulation, validation, production and testing – all in
a state-of-the-art industrial process that stands for
the very highest quality standards. Lamborghini drives
the technology development in its two research centers
the ACRC (Advanced Composite Research Center) and the
ACSL (Advanced Composite Structures Laboratory) through
collaborations with organisations such as Boeing, with
the resulting technology secured under a host of
patents.
“The Lamborghini Sesto Elemento shows how the future of
the super sports car can look – extreme lightweight
engineering, combined with extreme performance results
in extreme driving fun. We put all of our technological
competence into one stunning form to create the Sesto
Elemento,” comments Stephan Winkelmann, President and
CEO of Lamborghini. “It is our abilities in carbon-fiber
technology that have facilitated such a forward-thinking
concept, and we of course also benefit from the
undisputed lightweight expertise of Audi AG. Systematic
lightweight engineering is crucial for future super
sports cars: for the most dynamic performance, as well
as for low emissions. We will apply this technological
advantage right across our model range. Every future
Lamborghini will be touched by the spirit of the Sesto
Elemento.”
The basis is an extremely solid, stiff, safe and
lightweight carbon-fiber structure: the monocoque cell
of the Sesto Elemento. The entire front frame, the
exterior panels and crash boxes are also made from CFRP.
The Sesto Elemento’s major suspension components and the
rims are made from carbon fiber. The tailpipes are made
from Pyrosic, which is an advanced glass-ceramic matrix
composite, able to reach and stand very high
temperatures up to 900° celsius. Even the propeller
shaft is made of CFRP.
Carbon composite
materials are a key technology for the automotive
engineering of tomorrow, believes Lamborghini,
especially for high-performance sports cars. These
materials, made from carbon-fiber reinforced plastics,
combine the lowest weight with excellent characteristics
– they are extremely stiff and highly precise. Lighter
cars improve fuel consumption and CO2 emissions: above
all, however, it improves the power-to-weight ratio –
the crucial factor for a sports car – and thus the
performance. A sports car built using CFRP accelerates
faster, has outstanding handling and better braking.
Thanks to its power-to-weight ratio of only 1.75
kilograms per hp, the concept car delivers strong
performance. From a standing start, the Sesto Elemento
catapults itself to 100 km/h (62 mph) in a claimed 2.5
seconds while top speed is claimed at "well over 300
km/h".
Design
The Sesto Elemento advances the DNA of the Lamborghini
brand and integrates the functional consistency of
carbon-fiber technology into its design language. A
clear strength of the CFRP technology is the reduction
and integration of components – something that has been
used to its full extent in this innovative technology
concept. The material is visible everywhere. The Sesto
Elemento is finished in a new, matt-shimmer clear coat,
meaning that the CFRP structure can be seen throughout.
Yet the Sesto Elemento is not just black; during the
final stage of production the carbon fiber parts receive
a newly developed and patented coat. Nano-Technology
makes it possible to add fine crystals with a red
shimmer. Surfaces covered with this type of finish glow
red and deliver an outstanding effect. Further, the
surface is particularly robust.
The lines of the car have been designed to have clear
functions; the two vertical ribs at the front improve
the stiffness of the component and guide the cooling air
directly to the radiator behind them and to the brakes.
This guarantees the thermal wellbeing of the components
even under the toughest race track conditions. The
cooling air flows through two red triangular openings in
the hood beneath the front windscreen and through large
outlets in the side panels behind the front wheels.
Sharply cut headlamp units complete the front end.
Alongside the bi-xenon lamps there are four LEDs in each
unit. The low front end has a partially double-lipped
front spoiler pushed way out front and distinctively
formed air intakes.
The side profile is cut like a sharp wedge, with the
power center of the car just in front of the rear axle.
A distinctive sideline starts at the front wheel arch,
rises along the door towards the rear and ends at the
broad shoulders above the rear wheel. The triangle –
like the one around the door handle - is a recurring
design theme, defined by the precise contour edges in
the Sesto Elemento’s CFRP body. The points of the air
outlet triangles in the hood are carried through into
lines along the roof.
The wide sills form a connection between the air outlets
behind the front wheels and the large air inlets in
front of the rear wheels. These compartments house
components such as the radiators for cooling the engine
and transmission oil. The rims have a five-spoke design
and are made entirely from carbon fiber. They offer a
clear view of the high-performance brakes with
carbon-ceramic discs.
The Sesto Elemento’s rear overhang is extremely short
and, again, defined by optimum aerodynamics. The spoiler
is matched to the diffuser and a further air deflector
in the center to create downforce for extreme cornering
speeds and excellent high-speed directional stability.
The Pyrosic tailpipes are directed upwards through the
engine cover panel, which also incorporates ten
hexagonal openings and two air scoops behind the roof
for delivering fresh air to the V10 power plant.
A major strength of carbon-fiber technology is that
complex structures can be integrated into one single
component. This improves quality and reduces weight. On
the Lamborghini Sesto Elemento, the front and rear of
the body-shell are each manufactured in a single piece.
Engineers call this “cofango”, created by combining the
Italian word “cofano” (hood) with “parafango” (fender).
The large components are attached by using easily
removable fasteners, in order to have fast component
disassembly. The “cofango” is also reminiscent of an
icon from the brand’s history: in 1966, the legendary
Lamborghini Miura was unique as a mid-engine super
sports car – and its rear cover, too, could be opened in
one piece.
The minimalist approach has also been applied to the
interior, starting with the seats. Lamborghini has
dispensed completely with the conventional seat frame
and the internal structure is obtained and defined
directly from the forged composite tub, that on one side
plays a functional role and on the other side is the
base for the seat cushions, upholstered in fabric, which
are affixed directly to the carbon-fiber monocoque. The
correct ergonomics are provided by the steering wheel
which can be adjusted for height and reach, and by the
pedals, which can be electrically adjusted
longitudinally. The designers of Lamborghini Centro
Stile also dispensed with interior trim in the classic
sense. The dominant visual feature throughout is the
functional CFRP material – on the floor and roof of the
monocoque, on the doors and also on the cockpit and
center console. Even the electronic control unit for the
engine is mounted in plain sight – a very special kind
of aesthetic. The triangular cut-out is also evident as
a design feature – wherever material can be removed in
the interest of weight reduction. The controls are
presented in a highly concentrated format. The
instruments provide information primarily on engine and
road speed, as well as all parameters relating to engine
condition. Only three piezoelectric buttons grace the
center console – one to start the engine, one to shift
into reverse gear and another one for the lights.
Technology
The Sant’Agata Bolognese engineers had set themselves a
target that the Sesto Elemento had to stay below the
1,000 kilogram mark. And that target, Lamborghini
claims, has been achieved; at a curb weight of 999
kilograms, each hp produced by the V10 power unit has to
accelerate only 1.75 kilograms. This was made possible
by the systematic use of carbon-fiber technologies.
Lamborghini possesses experience in the field of
lightweight engineering, gathered over many years:
something clearly demonstrated by the brand’s series
production vehicles. The current Gallardo LP 570-4
Superleggera has a dry weight of only 1,340 kilograms,
marking a competitive best in this category of super
sports cars. Compared with the already extremely lean
Gallardo LP 560-4 Coupé, this represents a further
reduction of 70 kilograms, resulting largely from the
use of carbon fiber in the body-shell, interior and
technical components.
Lamborghini engineers stuck firmly to this approach for
the Sesto Elemento. Its structure consists almost
entirely of carbon fiber and is built using the
monocoque principle. Monocoque means that the vehicle’s
load-bearing structure is manufactured as a single
shell, with the physical properties of one component,
and thus makes optimum use of the extreme stiffness
offered by CFRP materials. Formula 1 racing cars have
been built using CFRP monocoques for decades – and
regularly provide clear evidence of their collision
safety. The monocoque in the Sesto Elemento, however, is
made using innovative Forged Composite technology – the
first time this has been done in an automobile. The
advantage of the Forged Composite is that the monocoque
is obtained through a one-shot process.
In the Lamborghini Sesto Elemento, the monocoque forms
the complete passenger cell. Connected to it are the
front subframe - incorporating the suspension points -
and the crash boxes, both also made using specialized
carbon-fiber technologies. The extreme stiffness of this
assembly guarantees not only a very high level of
safety, but also unparalleled handling precision. The
rear subframe with the engine mount and rear axle
suspension points is made from aluminum – another
lightweight material with which Lamborghini has a great
deal of experience.
An important element in optimum construction using CFRP
technology is the maximum integration of functions.
Thus, the body-shell exterior is made up only of the
roof section, which is part of the monocoque, the two
“cofango” covers front and rear with integrated
aerodynamic components and the doors. Each door consists
of only two elements, the exterior skin and the interior
cladding, both of which are also permanently bonded to
create one component.
The suspension and the area around the engine have also
been optimized with lightweight engineering. Alongside
aluminum components, there are also carbon-fiber control
arms: innovative forged composite technology is also
well-suited to this kind of high-load part. These
components are around 30 percent lighter than comparable
aluminum parts. The propeller shaft is also made of CFRP
by using Wrapping technology. This solution allowed the
Lamborghini engineers to get rid of the central joint,
bringing an important weight saving. The rims are also
made from CFRP, while the brake discs are from
carbon-ceramic composite material. A similar composite
material is used for the tailpipes on the exhaust system
– the compound of ceramic powder and synthetic resin
makes this carbon material extremely heat resistant. A
large number of screw fastenings feature a special
titanium alloy and joining technology from the aviation
sector.
Based on the form, function and operational demands of
the individual Sesto Elemento components, engineers from
Lamborghini’s R&D selected largely from three CFRP
manufacturing techniques within their technology tool
kit: Forged Composite: Here, materials with short carbon
fibers are hot pressed in a mould. The process
facilitates complex structures and is used for parts
such as the underside of the monocoque and the
suspension arms. Prepreg: The carbon-fiber mats are
soaked in a thermoset liquid resin. They are pressed in
moulds and cured in an oven under heat and pressure.
Prepreg components have a very good surface finish and
are therefore the preferred choice for use in visible
areas. Braiding: This is a method to manufacture
composite filament derived from the textile industry.
Each thread is diagonally intertwined on different
levels.
Drive
The engine of the Sesto Elemento is sourced from the
Gallardo LP 570-4 Superleggera. In the Sesto Elemento
too, the V10 unit is mounted “longitudinale posteriore”
– longitudinally behind the driver. The 570 hp output
equals 419 kW, all of which is available at 8,000 r/min.
The pulling power is just as impressive – with the
torque curve peaking at 540 Nm and 6,500 r/min. The V10
offers 5,204 cm3 of displacement, delivering a specific
output of 80.5 kW (109.6 hp) per liter of displacement.
The highlights of this long-stroke engine with an
aluminum crankcase include dry sump lubrication and a
cylinder angle of 90 degrees. Both solutions are an
integral part of the lightweight engineering approach,
as well as serving to lower the center of gravity and
thus tighten the handling characteristics. Ideal
combustion chamber fill comes courtesy of a switch-over
induction system and continually variable, chain-driven
camshafts. The Sesto Elemento is equipped with the
e.gear transmission, controlled in race car fashion via
shift paddles mounted on the steering wheel. The
automated system with electronic management shifts
smoothly through its six gears much faster than a human
being would be able to.
Competence
Lamborghini possesses experience with carbon-fiber
reinforced materials. As far back as 1983, it produced
the first prototype CFRP chassis for the Countach, with
the first series production parts appearing in 1985. The
current Lamborghini Murciélago is made largely from CFRP
– its body-in-white contains 93 kilograms of
carbon-fiber materials. The engine cover panel of the
Gallardo Spyder is one of the largest CFRP components
with class A surface quality in the automotive world.
The company is now working steadily to expand its
worldwide leading position. The new Advanced Composites
Research Center (ACRC) at the company headquarter in
Sant'Agata Bolognese is working on innovative
construction and production methods for carbon-fiber
elements in automobile design.
The Advanced Composite Research Center in Sant’Agata
Bolognese secures leading-edge research on innovative
materials and production methods for carbon fiber
elements for small production volumes. Here, over 30
experts develop vehicle components of all shapes and
sizes. They build prototypes and the associated
production tools while developing optimized production
technologies. Sophisticated systems largely developed
in-house allow extremely high precision levels as
engineers simulate manufacturing processes as well as
carry out crash tests on complex carbon-fiber
structures. Thanks to the extensively patented “RTM
Lambo” process, Lamborghini can use minimal pressure and
relatively low temperatures to manufacture carbon-fiber
components to the highest levels of quality, precision
and surface finish, from small parts to complex vehicle
structures. Further benefits include higher process
speeds, lower costs, and extremely light tooling.
The Lamborghini Advanced Composite Structures Laboratory
(ACSL) at the University of Washington uses experimental
tests to define the mechanical behavior of the different
materials and technologies using methodology from the
aviation industry. The team of research engineers in
Seattle works with very specific instruments and methods
in close cooperation with the R&D headquarters and the
ACRC in Sant’Agata Bolognese.
