Using a radical new aluminium-bonded body frame, the Aston Martin DB9 is one of the most sophisticated and technically advanced sports cars in the world. It is powered by the latest version of Aston Martin’s 6.0-litre V12, producing 450bhp and a top speed of 186mph. Yet the DB9 is significant well beyond being a class-leading sports car. It is the beginning of a new era for Aston Martin. It is the first car to be hand-made at Aston Martin’s new state-of-the-art facility in Gaydon, Warwickshire, where all future Aston Martin models will be developed and built.Sales of the model will start in Spring 2004, replacing the DB7, the most successful Aston Martin in history.
"Gaydon is the future of Aston Martin," says Dr Ulrich Bez, CEO of Aston Martin. "It combines cutting-edge high technology with hand-craftsmanship and tradition. It is probably the best facility of its type in the world, and the perfect showcase for how to design and build innovative sports and GT cars for the 21st Century."
"All cars built at Gaydon will be based on Aston Martin’s new VH [Vertical Horizontal] platform. It’s the first time in our history that we have had a totally flexible yet dedicated Aston Martin platform. The DB9 is the first car to use it making it the most important Aston Martin ever."
The body frame is the most structurally efficient in the world, taking into account strength, torsional rigidity and weight. It has double the rigidity of many rivals, as well as being lighter, resulting in superior handling and agility.
All body panels are either aluminium or lightweight composites with magnesium being used on the steering column and inner door frames. Even the gear selector paddles are made from magnesium alloy. The total weight is 1710kgs, extremely light for a V12-powered prestige 2+2 seater sports car with every imaginable luxury feature. This has a hugely beneficial effect on performance. Top speed of the manual is 186mph and 0-100 km/h (62mph) acceleration takes just 4.9 seconds. Other technologically radical features include a ZF ’drive-by-wire’ six-speed automatic gearbox that dispenses with a traditional gear lever. Instead, the drive, park, neutral and reverse controls are selected by buttons.
Touchtronic manual mode enables the driver to change gear using paddles mounted behind the steering wheel. The automatic gearchange has been tuned to provide the perfect balance between super-fast operation and comfortably smooth shifts. A conventional six-speed manual gearbox will also be offered.
The agility of the car is boosted by the perfect 50:50 weight distribution. This has been achieved partly by putting the gearbox at the rear. A carbon fibre drive shaft, running in a cast aluminium tube, delivers torque from the engine to the gearbox. Handling is further improved by the light aluminium wishbone suspension and aluminium bodied dampers. The whole DB9 cabin is handfinished in premium quality materials giving it a simple and functional feel.
Aluminium is used in the interior, reflecting the most commonly used material in the structure and body. Even details such as the instrument dials are made from aluminium. Features include full leather Bridge of Weir upholstery of the highest quality and a state of the art music system specially developed for Aston Martin by British sound experts Linn.
Among the many technological firsts is the ’message centre’ in the dashboard. It is an organic electroluminescent display (OEL), as opposed to the more common LCD. OELs have a higher and better contrast and are easier to read, especially when viewed at an angle. Of course, no Aston Martin would be an Aston Martin without a beautiful body. The DB9’s is modern and clean but retains much of its heritage. It is a modern interpretation of a traditional Aston Martin, the successor to such benchmark designs as the DB4 and DB5. The aluminium bonnet is long and extends all the way to the car’s leading edge. There is a minimum number of ’cut’ or ’shut’ lines, to aid styling simplicity and beauty.
The DB9 manages to combine all facets of style, quality and useability of a traditional Aston Martin without relying on retrospective detail or design. It is a totally modern Aston Martin.
In a long list of technological innovations, the most important is the bonded aluminium frame. Aston Martin believes it is the most structurally efficient body frame in the car industry. The new Aston Martin VH (vertical horizontal) aluminium structure gives immense benefits. It is very light, aiding performance, handling, economy and durability. It is also enormously strong. Despite being 25 percent lighter than the DB7 bodyshell, the DB9 structure has more than double the torsional rigidity.
This is the car’s backbone, the skeleton to which all the mechanical components are either directly or indirectly mounted. Drawing on the experience and technology pioneered in the Vanquish, the DB9’s frame is made entirely from aluminium. Die-cast, extruded and stamped aluminium components are bonded using immensely strong adhesives, supplemented by mechanical fixing using self-piercing rivets.
"It is far superior to the conventional steel saloon-based floorpan often used by high-value brands," says Aston Martin DB9 Chief Programme Engineer David King.
"The torsional rigidity of a car is a key factor in driving enjoyment and good handling. Any flexibility of the body compromises the performance of the suspension, delays vehicle response and corrupts feedback to the driver."
The tub is made in aluminium and the body panels are then fitted, again using adhesives, in the advanced body assembly area at Aston Martin’s new Gaydon facility. This adhesive is applied by a robot - the only one at Aston Martin. Computer controlled hot-air curing ensures the highest standards of accuracy and repeatability.
The bonding has enormously high stiffness, so that shakes and rattles are obliterated. Bonding also has excellent durability offering better stress distribution than welding - which is more prone to crack. The process is also used in the aircraft industry and Formula One.
There are also advances in the welding procedure. On the DB9, the upper and lower C-pillars are joined by advanced ultrasonic welding. It works by using a vibrating probe, called a sonotrode, which oscillates at 20,000 Hz. This high frequency of vibration agitates the molecules of the two aluminium panels to be joined, allowing them to form a molecular bond.
Because the bond takes place at a molecular level, it is 90 percent stronger than a conventional spot weld. It also requires only five percent of the energy of conventional welding, and as it generates no heat, there is no contamination or change in the characteristics or dimensions of the metal. Aston Martin is the first car company in the world to use this technique.
In addition to the aluminium frame, other lightweight or high-technology materials are used extensively. The bonnet, roof and rear wings are aluminium. The front wings and bootlid are composite. Cast aluminium is used in the windscreen surround, another industry first. Magnesium alloy, which is even lighter than aluminium, is used in the steering column assembly and inner door frames. The driveshaft is made from carbon fibre. It is part of the torque tube that rigidly connects the front engine to the rear gearbox. This arrangement helps the DB9 achieve perfect 50:50 weight distribution, further improving handling.
The DB9 uses all-round independent double-wishbone suspension. As the body frame is brand new, the chassis designers were able to start from scratch - rather than be forced to develop a suspension for an adapted saloon car platform. The front suspension is mounted on a cast aluminium subframe. At the rear, another subframe carries the rear suspension as well as the rear transaxle. Forged aluminium wishbones are used front and rear, as are aluminium-bodied dampers. This is rare, even on top-end sports and GT cars.
The steering rack is mounted ahead of the front wheels, which provides better control under extreme steering loads and heavy braking. Magnesium alloy is used in the construction of the steering column.Even the wheels have been specially designed to save weight. The 19-inch alloys are made using flow forming rather than casting. This saves about 1kg per wheel, benefiting unsprung mass, overall vehicle weight, and reducing rotational inertia. The tyres have been specially developed by Bridgestone.
On a 180+mph performance car, superb brakes are essential. The large discs are ventilated and grooved, rather than cross-drilled.
"Grooving is more efficient than cross drilling," says David King. "The pads are kept cleaner and work more effectively. Also, brake pad dust can block cross-drilled discs, which reduces braking performance."
The callipers are made from a single casting, rather than being fabricated in two halves and then bolted together. This increases strength and rigidity and gives superior braking performance at high speeds.
"This project was such a pleasure to work on," comments King. "We really could start from scratch in just about every area which rarely happens in the car business. We were not fighting compromises, such as having to adapt a saloon car component into a sports car."
Braking is improved by Electronic Brakeforce Distribution (EBD), which is computer controlled to optimise the front-to-rear brake balance, and by Brake Assist - in which the car’s electronics detect when the driver wants to emergency brake and automatically applies maximum braking force, cutting stopping distance. There’s also the latest anti-lock (ABS) system, which prevents the car skidding or sliding out of control.
LED tail lamps improve rear lighting performance and also react quicker - in braking, for example - than conventional incandescent bulbs. Their design in the DB9 is novel: the tail and brake lamps project through a reflector, which disperses the rays more evenly, further improving lighting performance. This also gets rid of the little ’hot spots’ that make up most LED tail lamps. Rather than a series of clearly visible dots, the light is one solid block.
Dynamic Stability Control (DSC) is standard. DSC is an advanced electronic control system that continually analyses wheel speeds, steering angle and yaw rate. It reduces the risk of skids by automatically applying braking to individual wheels, or reducing engine torque.
The DB9’s entire electrical architecture is state-of-the-art, the result of a partnership with fellow Premier Automotive Group member Volvo, which uses multiplex electrical systems in its product range. "It’s a high volume but very advanced system, exactly what we wanted," says Aston Martin’s Chief Engineer for Electrical and Electronics Sean Morris. "Every module on the car talks to every other module."
The air conditioning and climate control system is one of the most compact and efficient units in production.
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