Press Release
Page 1: Design
Page 2: Technology (I)
Page 3: Technology (II)
Page 4: Specifications
TECHNOLOGY
The DB9 is one of the most sophisticated 2+2 sports cars available in the world today.
The Aston Martin engineers' goal was to make a beautiful, distinctive car that was also outstandingly nimble and fast, and a car that was a worthy successor to the DB7 - the best selling Aston Martin in history.
In every case, technology is used to make the car better and to make the driving experience more enjoyable. In most cases, the technology is invisible, always there, always helpful, never intrusive.
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 frame 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 calipers 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.
The instrument pack is particularly attractive and innovative and all dials are made from aluminium. Microperforations allow the warning lights to illuminate through the aluminium. The rev counter runs anti-clockwise to maximise the visible area for the central electronic display, in the main instrument cluster. It's also a nice reminder of earlier Aston Martin models such as the Atom and the DB2.
There is no conventional red line on the tachometer. A red warning symbol will be displayed when maximum revs are reached but - thanks to the high-tech electronics - the 'red line' varies, depending on the engine's mileage, how recently the engine has been started, and ambient temperature.
The electronic message displays in the main instrument cluster, and in the centre console, are organic electroluminescent displays (OEL). This is another car industry first.
There are many benefits to OELs compared with conventional LCDs, including higher resolution and greater contrast, and improved clarity, particularly when viewed from an angle.
The ICE system is state of the art. It's been developed by Scottish-based Hi Fi experts Linn, and includes its own amplifier and speakers that are specially designed for the DB9. It also benefits from the DB9's high-quality fibre optic electronics, which pass signals with total clarity. The top-of-the-range 950W Linn Hi Fi system uses 10 speakers and a 200W sub-woofer controlled by an in-built accelerometer that even compensates for changes of pressure in the car's interior.
"The goal was to make the finest ICE system of any car in the world," says Sean Morris, "and I think we have succeeded."
