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JAGUAR INTRODUCES ALL-NEW 2004 XJ RANGE FOR 2004

Embargo release date: 21st December 2002 00:01:00

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THE NEW XJ AT A GLANCE

2004 Technical Specifications

• The new XJ is the most advanced production Jaguar ever
• It is the seventh generation of the car recognized as the definitive Jaguar sedan.
• An aluminum monocoque body replaces traditional steel construction.
• Longer, taller and wider than its predecessor – with more interior room in every dimension.
• Constructed using rivet bonding and adhesives – state-of-the-art techniques learned from the aerospace industry.
• The new XJ’s body is 60 percent stiffer yet 40 percent lighter – the XJ8 is almost 200 lbs lighter than its predecessor.
• Up to 570 lb lighter than the competition.
• Engines are a new 4.2-liter V8 and a 4.2-liter V8 supercharged, the later of these producing 390 bhp (SAE).
• All models feature an advanced six-speed ZF automatic transmission. There is no manual gearbox option.
• The new XJ is both quicker and more economical across the board than the outgoing generation – and many of its competitors. As an example, the quickest model in the new XJ range, the XJR, dispatches the 0-60 mph sprint in just 5.0 seconds and has a top speed electronically limited to 155 mph. The XJ8 records 6.3 seconds 0-60 mph and has a top speed electronically limited to 121 mph.
• The new XJ is among the safest cars in its class, with ground-breaking technologies such as Jaguar’s innovative A.R.T.S. Adaptive Restraint Technology System providing advanced protection at all times. It will be one of the first vehicles to meet the new FMVSS208 US crash standard.
• The new XJ is engineered for repairability. The unique Bolt-On-Front-End (BOFE) is designed to allow 10 mph frontal impact without the car suffering structural damage. The assembly has impact-absorbing properties including extruded aluminum ‘crash cans’ that channel impact energy onward from the bumper beam in a controlled path.
• In line with Jaguar’s continuing determination to offer relevant driver-assisting technologies, features of the new XJ include Dynamic Stability Control, Adaptive Cruise Control (with Forward Alert function), Emergency Brake Assist and Jaguar Voice.
• All new XJs have air suspension and a new generation of Jaguar’s sophisticated Computer Active Technology Suspension (CATS) as standard.
• Official EPA fuel economy figures for the new XJ8 and XJR are yet to be approved. The official European figures suggest a combined fuel economy improvement in the region of 10%. With this in mind, Jaguar expects to be highly competitive in the luxury segment.
• Prices will be announced just prior to the new XJ going on sale in late spring.

AN OVERVIEW

Mike Beasley, Managing Director, Jaguar Cars

The XJ sedan is the bedrock on which the Jaguar of today is based. Seven generations of XJ – from the very first XJ6 unveiled by Sir William Lyons in the 1968, to the all-new model that made its public debut in September 2002 – have taken the mantle of the definitive Jaguar sedan. Total production since the first XJ model in 1968 is now comfortably past 800,000 cars – more than half of all Jaguars ever built.

Representing contemporary British automotive luxury at its best, each generation of XJ has delivered the blend of attraction that Jaguar customers demand: elegance, style, comfort and spirited performance.

The all-new XJ has all this and much more besides. Not only is it the ultimate expression of Jaguar luxury sedan car engineering, it is also the most advanced Jaguar ever.

Jaguar has a well-documented history of working with aluminum, but with the new XJ the technologies used have moved to an altogether different level.

Pioneering a new lightweight vehicle architecture that is centered on a conventional monocoque body structure rather than an unnecessarily exotic space-frame, Jaguar engineers have developed a car that is larger in every respect than the model it replaces and has more features and driver-assisting technologies – and yet weighs almost 200 lbs less than the outgoing generation. Referring to a large sedan as a lightweight vehicle may seem incongruous, but the new XJ fully deserves – and earns – this label.

The benefits of reduced mass are in place all the time, from the moment the wheel start turning. In addition to measurables such as fuel economy, emissions and performance, the subjective issues of handling and ride also feature.

In the new XJ, Jaguar’s engineers have created a vehicle that is very agile. It is also quicker and more economical than the outgoing generation. A comparison between XJRs shows that the new XJ is quicker to 60 mph (5.0 seconds versus 5.3 seconds) and yet returns superior fuel economy. Top speed of XJ8 is an electronically limited 121 mph with XJR reaching 155 mph.

These levels of customer gain in areas that are becoming ever more important, especially in the luxury sector, five the new Jaguar XJ significant advantages over its main competition. And that’s without considering the driving experience, the traditional jaguar attractions of craftsmanship, style and luxury, and the impressive array of driver-friendly technologies that make life behind the wheel of the new XJ more relaxing and enjoyable – and safer.

The U.S. XJ range consists of a high level of standard equipment and a simplified model line-up: the normally aspirated XJ8 and supercharged XJR.

Engineering Elegance

The results of these identified that the XJ, the first design of which originated in the 1960s, had to evolve to address the requirements of today’s luxury sedan customers – including the demand for more interior space.

Addressing this without losing the distinctive proportions and character of the XJ was undeniably a challenge. Ian Callum, Jaguar Cars’ Director of Design, worked with his team to deliver a car that is bigger in all respects than its predecessor with a more spacious interior. The exterior proportions are subtly transformed to reflect the added space for occupants and their luggage.

"The new XJ is a dynamic looking car," says Callum. "And when you position it alongside major competitors, it is also clearly very elegant."

He continues: "This is a more modern car in terms of its proportions, and while for practical packaging reasons the trunk and doors are larger, the slimmer glass-to-door ratio results are in a truly contemporary design."

The new XJ design moves to a more cab-forward approach, positioning the wheels closer to the corners, incorporating a shorter hood and a shallower rake angle for the larger windshield.

The new hood retains the highly sculpted shape that is characteristic of the XJ over the years. Its leading edge – and indeed the leading edge of the fenders – still wraps around the shape of the headlights, which themselves have evolved into a more distinct element of the front design.

The new XJ’s dynamic design is also evident in its profile, says Callum. "It has a lot more of a ‘wedge’ now, starting dynamically at the front and powering toward the back. All the power is on the back wheels, something that has always been the case with Jaguar."

The XJ design team succeeded in accommodating a higher trunk lid while retaining the classic Jaguar ‘haunched’ design, hinting at the new car’s potential power and performance.

Precise weight-saving construction

Compromise was unacceptable – and aluminum was the answer.

Intensive studies led by Jaguar engineers at the Whitley Engineering Center in Coventry, England had already exposed the potential value of an aluminum-intensive body structure joined in an innovative fashion using rivets and adhesives. It was soon very apparent that this was the direction to take.

"We chose the lightweight vehicle architecture for the new XJ not because it was something new," says XJ Chief Program Engineer, David Scholes, "but because it would help us deliver significant benefits for our customers. Ultimately, they may not care whether the body structure is aluminum or steel, but the Jaguar customer does care very much about performance, dynamics, fuel economy, emissions and safety. The choice was clear."

The new XJ’s body structure comprises pressings of sheet aluminum combined with aluminum alloy extrusions and aluminum castings. Jaguar’s engineers adopted the proven construction techniques of the aerospace industry to assemble this structure and in volume production, the new Jaguar XJ represents an industry-first use of rivet-bonding construction for an aluminum-intensive monocoque body.

Rivet-bonding uses self-piercing rivets and epoxy adhesives for strength, robustness and durability when joining aluminum pressings. The adhesives applied robotically during assembly, heat-cure to optimal strength during the vehicle painting process. Approaching 3,200 rivets are sued in the construction of the new body.

The body of the new XJ is significantly stiffer – by 60 percent – and lighter by 40 percent than its predecessor.

In addition to the advanced nature of the body construction, the craftsmanship and precision evident in the new XJ are indicative of Jaguar’s determination to ensure customers experience total satisfaction.

Panel gaps are smaller and even more precise than in the previous model. Door shut lines are designed with a uniform gap of 3.8 mm to the bumper, sill and an adjoining door. The doors open wide – front doors to 62 degrees, rear doors to 65 degrees – to assure ease of entry and exit for occupants.

The hood and trunk both use four-bar-link hinges equipped with gas-assisted struts, and gaps on these major closures are also extremely precise at 3.5 mm from hood to bumper and trunk to bumper. Extensive use of the lightweight components in key areas of the structure ensured the new XJ met the weight targets set by the engineering team. These areas include:

• Bake-hardened aluminum sheet metal pressings for the new XJ’s exterior panels, offering added resilience against dents and dings
• High-pressure vacuum die castings for suspension and driveline component mounting points, which are both lightweight and highly resistant to bending and contribute to the precision and comfort of the XJ’s steering, ride and handling
• Aluminum alloy extrusions, utilized in the door structures for high strength against potential aerodynamic wind noise and for enhanced security, are also found in the front and rear bumper beams and used for floor and roof reinforcements

The inside story

And yet alongside these practical considerations, the interior of the new XJ remains warm and inviting – a classic Jaguar interior. Despite the generous amount of space inside the cabin, the driver and passengers still feel cosseted, the ambience set off by real walnut veneers and hand-stitched leather.

With significantly more headroom, legroom, shoulder room and rear-seat knee room, the new XJ interior provides a comfortable and relaxing environment for five adults.

The new seat designs were rated in Jaguar customer research as the most comfortable in their class. The 12- or 16-way adjustable front seats with electrically adjustable headrests are complemented by standard-fit electrically adjustable pedals and steering column, allowing drivers of widely varying statures to find the ideal driving position.

The new electronic parking brake, which eliminates the need for a traditional handbrake lever and also features drive away release, is itself an elegant design detail. Situated just behind the J-gate transmission shift lever, the electronic ‘switch’ frees additional space for the comfort of front-seat occupants.

Depending on the model or customer requirements, there is a choice of two different rear seating configurations: a fixed bench seat for three passengers, or a twin electric bench seat that accommodates three passengers.

Overall, interior volume has increased not only for occupants but also for luggage. At 6.6 cu ft., the trunk is more than 25 percent larger than the previous XJ’s – and event he glove box is bigger. The trunk can now accommodate four sets of golf clubs, while the previous XJ could accommodate two.

When XJ drivers and their passengers are comfortably settled in their seats, Jaguar’s philosophy of incorporating relevant technologies quickly becomes evident. From the intuitive and relaxed interfaces between occupants and the vehicle systems – an approach that separates Jaguar from many of its competitors – to the electronic driver aids, the new XJ makes you feel instantly at home.

"You don’t have to be a computer programmer to operate this car," comments David Scholes, XJ Chief Program Engineer. "Our customers are emphatic in their opposition to gratuitous technology and unwanted features intruding on their driving experience; it should be there when you need it but should never impose itself."

The new Jaguar XJ’s relevant technologies are centered on easing driver ergonomics, enhancing passenger comfort, expanding entertainment possibilities and developing voice-activated systems to reduce driver distractions.

Advanced telematics and communications technologies include a seven-inch LCD touchscreen display that provides fingertip control of climate, audio and DVD navigation systems (featuring zip code programming).

In the rear of the new XJ, a multimedia system allows passengers to access audio and video systems independently of the driver and front seat passenger. As an example, the front passenger can be listening to a CD, while one of the rear passengers is viewing a film on DVD and the other rear passenger plays a video game.

Two 6.5 inch color display screens, available in the optional multimedia package, are mounted in the rear of the front seat head restraints for video and TV viewing. Rear-seat passengers use headphones to listen to the audio output in comfort.

JaguarVoice, an industry-first when introduced on the S-TYPE in 1999, provides drivers and rear passengers with access to voice-activated control of compatible Jaguar systems, including primary audio functions, telephone, climate control, navigation systems and in-vehicle displays. Jaguar has made voice activation – a technology to reduce distraction when driving – an ongoing research priority. All XJs are prewired for easy installation of the desired language module.

High quality audio systems are another Jaguar trademark, and the new XJ is no exception. The eight-speaker sound system fitted to XJ8 features a single-slot CD and radio. The 320 watt Jaguar Premium sound system with 12 speakers, digital sound processing, power amplifier, subwoofers, as well as the remote six-disc CD changer and single-slot CD/radio, is standard on XJR and optional on XJ8.

Safety and crash repair

"Our target in developing the new Jaguar XJ was to produce one of the world’s safest cars," explains David Scholes, XJ Chief Program Engineer. "And the body structure is the foundation of the car’s safety performance."

The new XJ will have excellent crash protection and repair credentials, the aluminum-intensive body structure having already proven its strength in Jaguar’s own ‘real-world’ crash-test programs. Prior to the first XJ prototype crashing into a barrier, Jaguar engineers performed more than 500 computer-simulated crash events using sophisticated crash-modeling software and this was followed up by physical tests.

Being lighter than the equivalent steel body, the XJ body structure carries significantly less kinetic energy into a collision, reducing the amount of energy that has to be absorbed by the body in an accident. Front and rear crush zones in the body structure absorb crash energy progressively while protecting the integrity of the cabin, and the ‘tube-in-tube’ propshaft features built-in crash properties to absorb collision energy.

In addition, the new XJ promises excellent side impact protection, resulting from a very strong center pillar with a wide, tapered base, extruded aluminum lateral floor reinforcements, and door beam extrusions.

The architecture of the new XJ is engineered for ease of repairability, a key factor in the determination of insurance premiums. Engineering techniques used include a bolt-on front-end module – BOFE – that is designed to reduce the cost of repairing front-end collision damage. This can withstand an impact of 10 mph without structural damage being inflicted, the assembly incorporating impact-absorbing properties between the front-end module and the body shell.

The exterior bumpers of the new XJ are designed to withstand a 5 mph impact without structural damage. Made from injection-molded plastic, they incorporate side markers and fog lamps.

In addition, ‘lift-off’ door hinges make removal simple if collision repair is needed, reducing time and cost, while the bolt-on front wings are easy to remove and replace – another repair cost savings for the owner.

As with all new Jaguars sold in the U.S., the new XJ comes with a comprehensive four-year 50,000 mile warranty.

The right tools for the job

"Computers don’t engineer cars, people do," says David Scholes, XJ Chief Program Engineer. "Our tools are designed to enable every member of the engineering team to achieve the excellence that is the hallmark of Jaguar."

Jaguar North America will have a repair network of facilities and trained technicians in place ahead of the XJ’s launch. These facilities will offer a two-tiered approach to structural and cosmetic damage and repair.

Over the past ten years, Jaguar has transformed its approach to quality, introducing state-of-the-art tools and procedures. The key quality technique utilized today is called simply Advanced Quality Planning (AQP). This structured methodology optimizes product quality by identifying potential problems and ‘designing out’ the issue so that it never arises. AQP covers all stages of development, from early Computer-Aided Engineering (CAE) through to Statistical Process Control (SPC) of production processes. Anything that might eventually result in a potential problem – from a squeak or rattle to a major system failure – is identified and eradicated at a very early stage.

Any new Jaguar must be resilient to the widest extremes of climate, from the cold of an Alaskan winter to the heat of high summer in the Arizona desert – all the while performing at 100 percent regardless of driving styles or conditions. At prototype stage all Jaguars are subject to rigorous testing in some of the world’s most demanding conditions to verify robustness. One particularly demanding internal test simulates a vehicle lifetime through high-mileage accumulation over a wide variety of demanding and severe road conditions. Jaguar engineers were so confident that the new XJ would pass the lifespan test with flying colors – which it duly did – that they had already arranged for the same prototypes to undergo another full round of the test. The result? Another pass – so even before its public introduction, prototypes of the new XJ have already been driven over two normal lifespans! Of course Jaguar still believes in the personal touch as each XJ receives a five mile road test in the hands of a factory test driver.

Engines and powertrain

The XJ8 shares its larger 4.2-liter AJ-V8 engine with the recently launched 2003 Jaguar S-TYPE and 2003 Jaguar XK. The increase in displacement from 4.0 to 4.2-liters delivers seven percent more power and torque.

The supercharged 4.2-liter AJ-V8 continues – and extends – the Jaguar tradition of offering the breathtaking performance of a supercharged engine with the flagship of the range. The 390 bhp (SAE) supercharged 4.2-liter engine produces 33 percent more power than the naturally aspirated version with which it shares its underlying technology.

Developed at Jaguar’s Whitley Engineering Centre in Coventry, England, both new engines deliver refined performance and driveability in the Jaguar tradition.

A dynamic approach

New front and rear suspension systems – with the refinement of standard air suspension and enhanced Computer Active Technology Suspension (CATS) adaptive damping – take ride comfort and vehicle handling to new levels.

The suspensions incorporate extensive lightweight materials and are designed to complement the lightweight but stiff aluminum body structure that provides a rigid foundation for handling, steering and braking performance.

Fitting air suspension across the whole XJ range delivers major advantages over traditional coil-spring suspension systems in terms of comfort and refinement, providing optimum ride quality regardless of load conditions and ensuring that the vehicle’s full suspension travel is always available to soak up bumps or irregular road surfaces.

The XJ’s air suspension system uses air spring/damper units in lieu of the coil-spring/damper units of a traditional system. Height sensors at the four corners of the car feed vehicle height data to an electronic control module in the trunk and the system automatically lowers the XJ’s ride height by 15 mm at 100 mph. This improves aerodynamic efficiency, vehicle stability and fuel economy during high-speed cruising.

The new XJ’s suspension system also features the latest version of Jaguar’s sophisticated CATS system as standard on all models. This optimizes ride refinement under all conditions with two-stage adaptive damping under electronic control, but is so refined that the drive is unaware that damping conditions are changing.

The new XJ also features an impressive array of electronic driver aids, including four-channel anti-lock braking (ABS) with Emergency Brake Assist (EBA), the former a latest generation system that operates in a more refined manner than previously.

EBA helps the driver in an emergency when maximum power isn’t being applied, assessing the urgency with which the driver hits the brake pedal and instantly applying maximum available braking power if it is needed.

A new Dynamic Stability Control (DSC) system reacts to and controls both understeer and oversteer, which Traction Control helps provide optimum tractive power under acceleration by preventing the drive wheels from spinning when pulling away or cornering.

Jaguar’s innovative and award-winning Adaptive Cruise Control (ACC) system offers major advantages over conventional cruise control systems. Using microwave radar technology to overcome the need for the driver to adjust speed – either by disengaging cruise control manually or applying the brakes – when approaching slower traffic on the road ahead, ACC automatically adjusts the throttle (and may also apply limited braking) to reach a speed that is compatible with traffic ahead.

ACC features Forward Alert, which provides an audible early warning of slowing traffic ahead but does not intervene by adjusting the throttle or applying the brakes.

The plant that Jaguar built

Many of the new manufacturing techniques used in XJ construction were honed by the aerospace industry. Instead of the conventional spot welding used on a steel body structure, the new Jaguar XJ uses structural adhesives and rivets to assemble the unibody structure of aluminum pressings, extrusions and castings which form the foundation of the vehicle.

Each Jaguar XJ contains approximately 3,200 rivets and nearly 400 feet of adhesives. The combination of rivets and adhesives, which cure in the heat of the subsequent paint process, results in a body structure that is extremely strong and stiff but light in weight.

The new Jaguar XJ bodyshop facility makes extensive use of automation – not unusual in modern vehicle construction, but in this case very much state-of-the-art. Eighty-eight robots apply structural adhesives and install the self-piercing rivets in the vehicle structure. Extensive simulation work using powerful computer modeling tools, combined with prototype prove-out, has ensured uncompromising Jaguar quality in each step of the assembly process.

The body assembly operation is surprisingly clean and quiet. Gone are the sights, sounds, sparks and residue of a spot-welding process. Decibel levels have been significantly reduced throughout the assembly hall. Following the application of every 30th rivet, the gun is tested for accuracy.

The lean manufacturing ethic of the new Jaguar XJ assembly process is configured for highly efficient movement of parts and components ensuring that each workstation is supplied efficiently with stock. The need for parts stores adjacent to each workstation has been cut dramatically, reducing the need for costly in-plant inventory.

Two in-house parts stores hold enough stock for approximately eight hours of assembly operation. Just-In-Time delivery from suppliers keeps these stores at their optimum fill rate.

Working together in virtual reality

This gave manufacturing engineers the opportunity to configure an assembly plant before anything was actually built, so that the XJ’s entire body shop existed on computer prior to its installation. Every step of the production process, down to each movement of an individual robot, was modeled in this fashion.

The production of the new Jaguar XJ required a new, dedicated aluminum pressing facility. Designed, engineered and constructed by Jaguar Cars, the new 103,000 sq ft. pressing plant is operated and managed by a technical partner consortium, Polynorm Stadco, under a long-term operating contract.

Another key partner in the new XJ program is Alcan, the supplier of all the aluminum used in the car. Supplying the pressing facility via local warehouses capable of storing up to 20 days’ supply of raw material, Alcan was instrumental in the development of the construction techniques used in the new XJ, and served as the primary technical resource in early feasibility studies.

The end result

There can be no argument that in designing, engineering and constructing the new XJ, Jaguar has moved both itself and the wider automotive industry forward in the drive to reduce weight and enjoy the resulting benefits in terms of performance, fuel economy, emissions, crash safety, vehicle dynamics and recyclability.

The new technologies and pioneering techniques not only make the XJ the car it is, they also reinforce Jaguar’s standing as a world leader in advanced vehicle design and relevant, user-friendly driver aids.

And if you think the new XJ is impressive so far, just wait until you drive it…

AND NOT A LOT OF PEOPLE KNOW THAT…

• As Swallow Sidecars, the company that became Jaguar produced its first aluminum ‘vehicle’ in 1922 - a motorcycle sidecar
• The aluminum body shell of the new XJ weighs just 485 lbs – the steel equivalent is 794 lbs
• Each new XJ is assembled using almost 3,200 rivets and more than 394 ft of adhesives
• The XJ8 is actually 68 lbs lighter than the 4.2 liter V8 S-TYPE and is also 8 inches longer in length
• When you lock the doors of the new XJ, the available power folding door mirrors fold in automatically. Unlock them and the mirrors fold back out, at the same time illuminating on the underside to light your way to the door
• Prototypes of the new XJ underwent the equivalent of two lifetime’s motoring in simulated testing
• 88 robots apply the rivets and adhesives used in the construction of the new XJ
• The front door of a new XJ weighs 23 lbs – that’s 45 percent less than the equivalent steel door
• The new XJ underwent more than 500 computer-simulated crash tests before its first physical barrier test. It performed to the high standard expected
• In the event of a side curtain airbag being activated, it fills to 2.75 inches thick fully inflated capacity in less than 30 milliseconds
• The doors and trunk of the new XJ lock automatically when vehicle speed exceeds 5 mph after moving off
• The ride height of the new XJ automatically lowers by approximately half an inch at 100 mph to improve stability and refinement
• The Adaptive Cruise Control radar takes 40 measurements on each horizontal scan
• The XJ’s air suspension ‘wakes up’ every 24 hours and levels the vehicle when it is parked and not in use
• To support its electrical and electronic systems, the new XJ has 28 wiring and fiber-optic assemblies and three fuse boxes
• The supercharger spins five percent faster than in the previous XJR

EXTERIOR DESIGN AND ENGINEERING

Ian Callum, Director of Design, Jaguar Cars s

Larger, more spacious car retains distinctive XJ proportions

The new Jaguar XJ delivered by Callum and his design team is longer, taller and wider than its predecessor with a more spacious interior. Under Callum’s leadership, the exterior proportions of the Jaguar XJ have subtly transformed to reflect the added space for occupants and their luggage.

"The new XJ is quite a dynamic looking car," says Callum. "When you position it alongside major competitors, it is also clearly a very elegant car. It’s much more robust looking than the previous model, creating a real presence on the road."

"This is also a more modern looking car in terms of its proportions," explains Callum. "Although, for practical packaging reasons, the trunk and doors are larger, the slimmer glass-to-door proportions result in a truly contemporary design."

The new XJ design moves to a more cab-forward approach, positioning the wheels closer to the corners, incorporating a shorter hood and a shallower rake angle for the larger windshield.

Reinterprets classic XJ dynamic design cues

To differentiate the new XJ from its predecessor, the design team crafted a new grille design to sit alongside the mesh grille of the XJR. Distinguished by intersecting vertical and horizontal bars, it was inspired by the original XJ6.

More dynamic in profile

The XJ design team succeeded in crafting the XJ’s rear to accommodate a higher trunk lid while retaining the classic Jaguar ‘haunched’ design, hinting at the new car’s potential power and performance. The new XJ also evokes the classic Jaguar boat-tail shape, accentuated by the slope of the higher trunk lid.

New Xenon headlights

Distinctive LED tail lamps

Larger but lighter new body and innovative aerospace technology

As clever as the design team were in maintaining the visual links with the Jaguar XJ heritage, a larger XJ posed an even greater challenge for Jaguar engineers. Equipped with even more features, as well as being bigger, this would surely mean increased weight. Without innovation, the new vehicle would have suffered in terms of performance, fuel economy and range, and emissions.

Led by Chief Program Engineer David Scholes, the engineering team quickly realized that a breakthrough was needed to solve the weight dilemma, while simultaneously enhancing the performance capabilities and comprehensive list of luxury features the new XJ would offer its customers.

Intensive studies led by Jaguar engineers at the Whitley Engineering Center in Coventry, England – working closely with their colleagues in Ford Research Laboratories in Dearborn, USA – had already shown the potential for adapting aerospace-style rivet-bonding to create a body shell from aluminum instead of steel. The technology delivered not only significant weight savings, but also major advances in body stiffness, benefiting vehicle dynamics, safety, refinement and durability.

"We chose the lightweight vehicle architecture for the new XJ not because it was something new," says David Scholes, "but because it would help us deliver significant benefits for our customers. Ultimately, they may not care whether the body structure is aluminum or steel, but the Jaguar customer does care very much about performance, dynamics, fuel economy, emissions and safety. So the choice was clear."

AS a result, the body of the new XJ is significantly stiffer and lighter than its predecessor. The protective strength of its architecture also represents a groundbreaking advance in crashworthiness.

Rivet-bonding aluminum: an industry first in volume production

In volume production, the new Jaguar XJ represents an industry-first use of rivet-bonding construction of an aluminum-intensive, conventionally structured monocoque body.

Rivet-bonding uses self-piercing rivets and aerospace epoxy adhesives for strength, robustness and durability, when joining aluminum pressings. The adhesives, applied robotically during assembly, heat-curve to optimal strength during the vehicle painting process. Almost 3,200 rivets are used in the construction of the new body.

The exterior and interior structures of the hood and trunk are assembled using structural adhesives and a joining method called spot-clinching, in which one metal surface is physically clinched over the other in a series of joins similar in size to spot-welds. The edges of the hood and trunk are finished with a special ‘anti-flutter’ adhesive to reduce wind-noise potential.

Extensive use of light-weight components in key areas of structure

• Premium bake-hardened aluminum sheet metal pressings are used for the new XJ’s exterior panels, offering added resilience against dents and dings that can occur in crowded parking lots
• High-pressure vacuum aluminum die castings are used for mounting points for the suspension and driveline components. The castings are both lightweight and highly resistant to bending, contributing to the precision and comfort of the XJ’s steering, ride and handling
• High strength, ‘green sand’ aluminum castings are used as the interface for the new XJ’s bolt-on front-end (BOFE) assembly. This BOFE ensures that in most cases minor, low-speed crash damage can be contained in the easily replaceable components of the front-end assembly
• An aluminum, hydroformed alloy extrusion is used for the front-end radiator support. This pressurized hydraulic process is used to produce complex shapes in tubular components that are usually stronger than fabricated welded assemblies
• Magnesium, as strong as aluminum but 30 percent lighter still, is used for the new XJ’s seat frames and cross-car beam that supports the dashboard, instrument panel and steering column
• Aluminum alloy extrusions are utilized in the door structures for high strength against potential aerodynamic wind noise and for enhanced security. Extrusions are also found in the front and rear bumper beams, and as floor reinforcements

40 percent lighter and 60 percent stiffer

Closing the door on noise

Creating a quiet cabin is a challenge for automotive engineers, who battle to eliminate unwanted wind noise, tire roar and powertrain noise. At Jaguar, the science of sound is used not only to reduce noise but to actually shape it within the occupant cabin as part of the most comprehensive acoustic program ever undertaken by Jaguar engineers.

The modular doors of the new XJ are examples of Jaguar’s obsessive approach to creating a superbly refined cabin environment. They feature a high-strength upper structure, achieved with a hybrid structure of aluminum extrusions, castings and pressings that helps to resist aerodynamic pressure – particularly at high speeds – thereby minimizing wind noise. New triple door seals also protect against wind and road noise intrusion.

The new doors also close with a sound of reassuring quality, achieved through the elimination of metal-to-metal contact and applying ‘acoustic damping’ to individual components of the door. As a result, not only is each of the new XJ’s doors easy on the ear, they are also easy to open and close, thanks to the lightweight vehicle architecture.

Secondary bulkhead for enhanced cabin refinement

Other measures to ensure optimum cabin refinement include:

• New quiet camshaft drive-chains and acoustically tuned induction systems for all AJ-V8 engines
• Refined six-speed ZF automatic transmission with specially tuned transmission crossbar mount for maximum noise attenuation
• Isolated front and rear subframes and air suspension, which together minimize the effect of road-induced vibrations into the cabin
• Rigid cast aluminum damper towers and subframe attachment points, used in combination with bushings to help isolate road vibrations
• Highly precise and uniform body gaps, closures and glass fitment help to reduce wind noise
• Aerodynamically designed exterior mirrors produce less turbulence
• Acoustic underbody trays improve aerodynamic efficiency and reduce road-induced noise levels. These trays are the result of a 700-hour wind tunnel testing program
• All antennae are contained in the rear window glass, on the rear package tray and in the body structure. This eliminates ‘aerial’ wind noise
• Synthetic wheel arch liners reduce road noise, a benefit especially noticeable in wet conditions

Tailored precision: Jaguar craftsmanship more than meets the eye

The shut lines of the doors are designed for a uniform gap of 3.8 mm to the bumper sill and an adjoining door. The doors open wide – front doors to 62 degrees, rear doors to 65 degrees – to assure ease of entry and exit for occupants.

The hood and trunk both use four-bar-link hinges equipped with gas-assisted struts. The hood opens to an angle of 54 degrees. The trunk opens to 86 degrees, and is equipped with a release lever that allows it to be opened from within in an emergency.

Gaps on these major closures are also extremely precise being designed to be 3.5 mm from hood to bumper and trunk to bumper.

Repairability and insurance premiums

Elements of the Bolt-On assembly include:

• A hydroformed, aluminum extrusion bumper beam cross-member, providing both strength and crushability for minor collision damage, and continued robust protection in more severe impacts. It is fitted with an energy-absorbing foam cover
• Extruded aluminum ‘crash can,’ a structure that channels the onward impact energy from the bumper beam. The ‘sacrificial’ component is designed to crush predictably and ‘flatly’ in a minor impact, thus protecting the rest of the body structure and vulnerable components at the front end of the vehicle, such as the radiator
• A rigid aluminum casting ‘interface’ on each side of the vehicle is used as a robust stop for the crushing actions of the crash cans. The interface castings, manufactured with an advanced green casting method, are fitted to the outward ends of the main body’s lower structural rails
• The vehicle towing bracket is contained within the bolt-on structure
• ‘Lift-off’ door hinges enable east removal in the event of collision repair, reducing repair time and cost
• Bolt0on front fenders allow for easy removal and replacement in a collision repair – another repair cost savings for the owner
• The exterior bumpers of the new XJ are designed to withstand a 5 mph impact without structural damage. Made from injection-molded plastic, they incorporate side markers and fog lamps

Park Control System

Park Control warns the driver when the vehicle is approaching the proximity of another vehicle or a hard surface, like a wall or post in a car park. It emits a series of beep tones that increase in frequency as the vehicle approaches the object. At about 8 inches, the beep becomes a continuous tone.

The rear system becomes operational whenever reverse gear is selected with the ignition on. Park Control uses four ultrasonic sensors mounted in the bumpers.

Rain-Sensing wiper system

Non-stick windshield wiper blades

Power fold-back exterior mirrors

Ground illumination

Glass moonroof

INTERIOR DESIGN AND ENGINEERING

Ian Callum, Director of Design, Jaguar Cars

A warm, inviting, ‘classic Jaguar’ interior

"The interior is what you really fall in love with," says Callum. "It epitomizes what a Jaguar interior should be – warm, inviting, and not imposing. I always say that you should get out of a Jaguar feeling better than you did when you got in it, and that’s certainly true of this new XJ."

Comprehensively equipped with contemporary luxury car technology but restrained and conservative in style, the new XJ is distinguished by classic Jaguar design cues and hallmark attention to detail. This is complemented by real walnut veneers for the fascia, center console and door trims, together with new, softer leathers. The new seat designs are rated in Jaguar customer research as having the best comfort in their class. With 12- or 16-way adjustable front seats with electrically adjustable headrests and two different options for rear seating configurations, the new Jaguar XJ is equipped to pamper its occupants.

Significantly more headroom, legroom, shoulder room and rear-seat knee room combine to make the new XJ interior a comfortable and relaxing environment for five adults. Overall interior has increased not only for occupants but for luggage. Even the glove box is bigger.

Standard-fit electrically adjustable pedals and steering column allow drivers of widely varying statures to configure their preferred driving position.

A virtuoso Jaguar touch for the new XJ: Piano Black

Piano Black is a lustrous, satin-polished black finish that immediately differentiates the Jaguar XJ from rivals, adding the kind of subtle cachet found in other exclusive luxury goods. It is perhaps a small detail, but it reflects the importance of Jaguar craftsmanship to attention to such details in executing a luxury interior for discerning customers.

In every dimension, a more spacious Jaguar XJ

Improving interior and luggage space was a top priority for the development team. Longer, wider, and taller, the new XJ answers this desire without diminishing the style and panache of the Jaguar character. The new XJ has room for three adults to sit comfortably in the rear seat, with increased head room (38.4 inches), leg room (38.7 inches), knee room (2.8 inches) and shoulder room (58.3 inches) compared with the previous model.

Front-seat occupants also gain more space including almost 2 inches more leg room and approximately one inch more head and shoulder room.

Trunk space in the new XJ is also significantly bigger. Total trunk volume is up 3.9 cubic ft. – more than 25 percent – over the previous model. At 16.6 cubic ft. capacity, the new trunk has room for four golf bags, while still accommodating a full-size spare tire beneath the luggage compartment. The glove box is also larger, its design reflecting extensive customer research and feedback. The on-touch, chromium-plated release button is offset from the center for easier driver reach. A dedicated power point for accessories is located in the glove box, allowing a mobile phone to be recharged out of sight.

An easy-to-reach overhead console provides access to controls for cabin lights, moonroof operation and pre-programmed garage door or gate openers and rear sunblinds (if fitted). The console also contains microphones for integral telephone and JaguarVoice technology.

Comfortable new seats earn top marks

Key attributes of the new seating designs include:

• Front seats: 12-way power-adjustable for fore and aft, cushion tilt, seatback recline, lumbar and headrest height, and three position memory are standard on the XJ8. 16-way adjustable front seats, which add cushion-extension and additional lumbar support, are standard on XJR and optional on XJ8
• An electric seatbelt comfort system for the rear outboard occupants reduces belt tension to allow for greater freedom of movement
• A choice of two rear seating designs depending on model and customer needs:
• A fixed bench seat for three passengers, with two head restraints and four-way manual adjust
• A twin electric bench seat, accommodating three passengers, features electrically memorized recline of the seatback and four-way adjustable lumbar control for the outboard seating positions. Electric head restraint adjustment and electrically operated front passenger seat adjustment from the rear are also featured

Two distinct luxury interior design choices

The new 12-way seats have horizontal flutes. In the rear, a fixed rear bench seat with two manually adjustable head restraints is standard equipment, but premium luxury package owners may opt at extra cost for a twin electric bench seat with center console and power adjustment of lumbar support, seat back and head restraints.

Classic interiors feature contrasting color combinations, including dove/granite, sand/sable and all-charcoal option can also be selected.

Premium Luxury Package – The opulence of the XJ8 with premium luxury package is characterized by elements of the Classic interior with exclusive touches of added luxury, including plush, soft-grain ruched leather seats and trim, standard 16-way power-adjustable front seats, variable-heated seat cushions and backrests, power sunblind, lambswool rugs, Alpine audio system and upholstered dashtop. Exclusive to the Premium Luxury Package is an available ivory interior.

Performance Interior – The new Jaguar XJR features an exclusive interior design that reflects its performance capabilities. A unique seat design with 16-way power adjustability for the driver and front-seat passenger, has more pronounced lateral bolsters for the back and thighs to provide exactly the right balance of support and comfort.

Additional standard features on the XJR include heated front and rear seats, heated wood and leather steering wheel, power rear sunblind, and Alpine audio system, and radar-based adaptive cruise control (ACC).

Jaguar’s ‘relevant technologies’ philosophy

"You don’t have to be a computer programmer to operate this car," insists David Scholes, XJ Chief Program Engineer. "Our customers are emphatic in their opposition to gratuitous technology and unwanted features intruding on their driving experience, so the Jaguar philosophy is one of making technology relevant. It should be there when you need it but it should never impose itself."

The Jaguar XJ’s relevant technologies are centered on easing driver ergonomics, enhancing passenger comfort, expanding entertainment possibilities and developing voice-activated systems to reduce driver distractions.

Advanced telematics and communications technologies include a seven-inch LCD touchscreen display that employs thin-film transistor technology (TFT) to provide finger-tip control of climate, audio and DVD navigation systems (featuring zip code programming). The rear multimedia systems allows passengers to enjoy access to audio, TV, video and telephone systems independently of the driver or front seat passenger. They have the freedom to watch a DVD, for example, with no link to the front of the car. This exceptionally high level of integration is facilitated by fiber optics for fast, high quality data transfer.

• Ergonomically crafted: electrically adjustable pedals Ergonomic excellence was one of the top goals for the XJ program team. Led by the introduction of new adjustable pedals, the XJ has been engineered for this critical aspect of comfort, especially on long journeys
  
  The new feature allows drivers to position the pedals (maximum travel 2.5 inches) for their optimum driving position. Together with a steering column that is electrically adjustable for reach and tilt and a driver’s seat that is available with the flexibility of either 12-way or 16-way adjustability, this allows drivers of all shapes and sizes to feel completely at home behind the wheel and take advantage of the dynamic capabilities and performance of the new Jaguar XJ.
  
  Adjustment for the pedals’ fore and aft location and the steering wheel tilt and reach adjustment is operated by a combination switch mounted on the steering column
  
  The desired position of the pedals and steering wheel, as well as the driver seat and exterior mirrors, can be stored in the driver position memory system that allows three different drivers to retain their preferred positioning. There is also a tilt-mode that retracts the steering wheel and moves the seat to ease entering and exiting the vehicle
• Steering wheel controls allow the driver to operate the audio system, cruise control (including Adaptive Cruise Control, where fitted) and an integrated telephone, without taking a hand off the wheel
• The new electronic parking brake eliminates the need for a traditional parking brake lever. AS first seen on the Jaguar S-TYPE, this is in the form of a small control switch – itself an elegant design detail – behind the J-gate transmission shift lever. This new technology frees up additional space for the comfort of the XJ’s front-seat occupants

Advanced telematics and communications systems

• JaguarVoice, an industry-first for Jaguar in 1999, provides drivers and rear passengers with access to voice-activated control of compatible systems, including primary audio functions, teletext, telephone, climate control, navigation systems and in-vehicle displays. Jaguar has made voice activation – a technology to reduce distraction when driving – an ongoing research priority. All vehicles are pre-wired for installation of the desired language mode. The system will be available in North America with the following languages: English, French, and Spanish. A push-to-talk (PTT) button, located on the steering wheel and in the rear multimedia switchpack (where specified) activates the JaguarVoice system and automatically mutes the audio system volume for telephone use.
• DVD Navigation A Denso navigation system with a large seven-inch screen in available across the XJ range. Using exceptionally fast DVD technology to deliver timely mapping information to the clear, touch-sensitive screen, the system is easily programmed with the desired destination, such as a house number or street junction. Alternatively, a U.S. zip code can be entered into the system, which then calculates a route and instructs the driver via visual and voice guidance. If the driver strays off the route, the system recalculates a revised routing to the desired destination and guides accordingly. DVD technology allows complete mapping of the U.S. on one disk.
  
  Along the route, the system can indicate ‘point of interest’, including restaurants, hotels, fuel stations, parking areas and Jaguar dealers and can even be linked with the fuel gauge to automatically display nearby fuel stations when the fuel level indicated ‘low.’
  
  The navigation system receives signals from global positioning satellites (GPS) that allow its electronic control unit (ECU) to calculate the vehicle’s exact location – along with its speed and direction – using inputs from ABS system sensors and a gyroscopic sensor.
  
  The navigation system’s crystal clear screen is also used for touch-screen programming of vehicle systems. Navigation is optional across the range.
• New rear seat multimedia system This allows rear seat passengers to access the audio and video systems independently of the driver and front seat passenger. The front passenger could be listening to a CD, while one of the rear seat passengers is viewing a film on DVD and the other rear seat passenger plays a video game.
  
  Two 6.5-inch color display screens are mounted in the rear of the front seat head restraints for video and TV viewing. Rear-seat passengers use headphones to listen to the audio output in comfort.
  
  The rear multimedia switchpack controls audio and video signals and has an open architecture to accept all types of inputs from devices. Sockets for two accessory headphones are also located in the switchpack. The rear multimedia system is optional on XJR and XJ8 with Premium Luxury Package.
• High quality sound systems as standard The 8-speaker sound system fitted to XJ8 features a single-slot CD and radio with RDS, and automatic volume control. The system is pre-wired for a six-disc CD autochanger
• 320 watt Jaguar Premium sound system with 12 speakers, digital sound processing, power amplifier, subwoofers, as well as the remote six-disk CD autochanger and single-slot CD/radio, is fitted as standard on XJR and optional on XJ8
• New two- and four-zone climate control systems The Jaguar XJ’s primary climate control system uses new technology to mix cold and hot air to provide precise interior temperature control. The system features in-car temperature and humidity sensors – for integral anti-misting humidity control – plus a solar load sensor and filtration. The two zones provide separate driver and passenger controls

A second climate control unit serves the individually adjustable rear seating positions. Operated by a control panel in the center console, it allows passengers to choose a preferred temperature between 63°Fand 89°F, manually select from among seven available fan speeds and configure the air flow to the face, foot or bi-level, or alternatively choose a fully automatic mode to maintain the desired temperature.

Sophisticated electrical network

New functionality for the XJ is Smart Charging, a battery load management technology that manages the charging of the battery and its power supply to the vehicle. If the battery is low, Smart Charging prioritizes the vehicle’s electrical functions, allowing only essential systems to operate until the engine has been started and the battery receives charge.

The XJ’s battery is mounted inside the trunk, under the floor, adjacent to the spare wheel. This keeps it away from temperature extremes and so extends its life, while also improving weight distribution in the vehicle.

The XJ’s primary, 12-volt wiring system features electrical harnesses for the body, engine compartment, instrument panel and the engine itself. The new XJ also features a harness dedicated to the telematics systems. Additionally, XJ features extensive use of multiplexing to deliver sophisticated functionality, with four systems integrated:

• Standard Corporate Protocol (SCP) network controls low-speed, event-driven communications around the body, including such systems as the rear seat memory
• Controller Area Network (CAN) is used for the high speed powertrain systems, including the engine, transmission and air suspension system, as well as the instrument cluster.
• Digital Data Bus (D2B), a fiber-optic, high-bandwidth communication protocol for the high-speed, real-time communications needs of the telematics, navigation, phone, JaguarVoice, audio and multimedia systems.
• ISO 9141 BUS, the communications protocol used exclusively by Jaguar’s A.R.T.S. safety systems.

POWERTRAIN

A range of powerful and refined eight-cylinder engines

• 4.2-liter normally aspirated AJ-V8 producing 294 bhp (SAE)
• 4.2-liter supercharged AJ-V8 developing 390 bhp (SAE)

The larger 4.2-liter AJ-V8 engine is already used in the new Jaguar S-TYPE and 2003 Jaguar XK. The increase in displacement from 4.0 to 4.2 liters delivers seven percent more power and torque.

The supercharged 4.2-liter AJ-V8 continues – and extends – the Jaguar tradition of offering the breathtaking performance of a supercharged engine in the flagship of the range. The 390 bhp (SAE) supercharged 4.2-liter engine produces 33 percent more power than the naturally aspirated version with which it shares its underlying technology. On the way to its staggering torque potential of 399 lb ft (SAE), this engine produces more torque at 2000 rev/min than the BMW 745 achieves at its peak – and this in a car considerably lighter.

Developed at Jaguar’s Whitley Engineering Center in Coventry, England, both new engines deliver refined performance and driveability in the Jaguar tradition.

New Aj-V8 engine family

The range is led by the new 4.2-liter Aj-V8 engine, which is available in both naturally aspirated and supercharged versions. It replaces the respected 4.0-liter AJ-V8 used in the previous-generation XJ.

The 4196 cc, four-cam engine whose eight-cylinders are configured in a 90 degree V configuration, is characterized by enhanced refinement, fuel economy benefits and improved emissions performance.

The increased displacement and longer stroke of the 4.2 liter improves driveability and increases power throughout the rev range, with particular benefit at lower engine speeds. The already high compression ratio is increased to 11:1 (from 1.5:1), benefiting combustion efficiency. The inlet manifold structure is also optimized for improved response.

New, tuned inlet manifolds increase the engine’s performance throughout the range, by improving air/fuel distribution. This complements enhancements to the combustion system that reduce cold start emissions and improve low emission/high economy calibrations.

A responsive, vane-type Variable Cam Phasing (VCP) system optimizes the camshaft timing to deliver high torque across the rev range, improve idle stability and reduce emissions.

The normally aspirated 4.2-liter AJ-V8 brings a seven percent increase in power and torque over the outgoing 4.0-lietr AJ-V8, delivering 294 bhp (SAE) at 6000 rev/min. Peak torque of 303 lb ft (SAE) is produced at 4100 rev/min.

Supercharged 4.2-liter AJ-V8. The supercharged version of the 4.2-liter V8 is the heart of Jaguar’s performance flagship, the XJR. This achieves a peak horsepower of 390 bph at 6100 rev/min, a 33 percent increase over the normally aspirated variant. At least 86 percent of peak torque is available from 2000 rev/min to a peak of 399 lb ft (SAE) at 3500 rev/min. The supercharged 4.2-liter engine delivers eight percent greater power and five percent more torque than the previous 4.0-liter AJ-V8.

Forged, oil-cooled pistons, high fin-density intercoolers and a unique twin fuel pump system are fitted to handle the increased output. The mechanically driven Eaton supercharger has excellent boost characteristics which, combined with twin intercoolers, results in outstanding performance under all driving conditions. The Eaton supercharger spins 5 percent faster than the unit on its 4.0-liter engine predecessor.

The supercharged 4.2-liter AJ-V8 powers the flagship XJR.

Engineering features of the AJ-V8 engines

• Aluminum cylinder block with structural bedplate – The block/bedplate has been redesigned to further increase stiffness, reducing radiated noise levels and enhancing the new XJ’s impressive refinement.
• Variable Camshaft Phasing (VCP) – Faster engine response at all speeds is available due to inlet camshaft timing that is continuously variable according to demands and conditions.
• Branched exhaust manifolds – Tuning the primary length of the exhaust manifolds and pairing the manifold branches of contemporary cylinders improves volumetric efficiency and so ultimately engine performance.
• Cold start retard – Increased ignition spark retard minimizes the exhaust catalysts’ warm-up period from cold. This feature also reduces the need for cold-start enrichment, benefiting fuel economy and emissions performance.
• Fuel injectors – The use of multi-hole fuel injectors improves spray droplet size, enhancing combustion quality. Spray performance is now the equivalent of injectors featuring air-assist. The enhanced performance of the new fuel injectors also aids emissions and fuel economy by maximizing combustion efficiency.
• Electronic throttle with ‘limp home’ facility – The Engine Management System (EMS) electronically operates the engine throttles in response to pedal movements, In the unlikely event of a system failure, the EMS provides a ‘limp home’ mode in which the car may be driven with limited performance.
• Lightweight aluminum components – Any weight reduction aids responsiveness and acceleration. The new AJ-V8 engine family features lightweight components made from aluminum and magnesium alloy, the latter as strong and durable as aluminum but 30 percent lighter again.
• Silent chain camshaft drive – Finer pitch inverted tooth-chains are specified to drive the camshafts. These special chains and sprockets reduce the loading and lessen the radiated noise levels of the drive system by some 20 dBA.
• State-of-the-art ZF six-speed automatic transmission – All Jaguar XJ models are equipped with the state-of-the-art ZF 6HP26 six-speed automatic transmission introduced recently by Jaguar in the new Jaguar S-TYPE and XK sports cars.

The ZF transmission employs a planetary gear train principle using Lepelletier-type gear sets. This facilitates six forward gears with a dramatically reduced number of components – some 30 percent fewer than the XJ’s previous five-speed automatic. The result is a wide gear ratio spread and higher torque capacity that satisfy exacting performance requirements for off-the-line acceleration, high maximum speed and excellent fuel economy.

The transmission is controlled by a Bosch ‘Mechatronic’ brain – an integrated electro-hydraulic control module, housed as a single unit inside the transmission. The control module ensures the quality and consistency of gear shifts, as each module’s ECU (electronic control unit) is calibrated to its own unique hydraulic control body during the manufacturing process.

Using microhybrid printed circuit board technology, the ECU of the electrohydraulic module is compact and lightweight. Enclosed in a sealed metal housing, it remains totally impervious to the high temperatures and vibration that result from the unit being located inside the transmission. With a significantly reduced number of components and electrical connections, the Mechatronic control module also increases the overall reliability and robustness of the automatic transmission.

The new geartrain system and the use of plastic for the oil sump and the body of the Mechatronic control module, reduces weight by around 24 pounds compared with the previous five-speed automatic transmission.

Adaptive gearshift strategies for improved response

In ‘Sport’ mode, throttle pedal usage and cornering behavior are monitored to assess driving style and road conditions. When an enthusiastic driving style or a demanding road is detected, sixth gear is inhibited and the lower gears become more accessible in order to prevent unwanted ‘hunting’ between gears. Conversely, when cruising conditions are detected, sixth gear is once again made available to maximize driving refinement and economy.

Under heavy braking, the transmission will perform one or more downshifts to improve response to subsequent accelerator pedal application. Similarly if the throttle pedal is released rapidly following hard acceleration, one or more upshifts are inhibited to increase engine braking and also improve subsequent response. To complement these features, when cornering is detected transmission upshifts are inhibited and this is maintained for a short distance after the corner allowing the driver to achieve a smooth balance through the bend without unwanted shifts mid-corner.

New electronic ‘J-gate’ gear selector

Key features of the J-gate include:

• Shift-by-wire (on manual side of the J-gate – gears 2,3,4 and 5)
• Weight reduction (magnesium mounting frame)
• Revised mounting position for improved craftsmanship and refinement
• New design of the gearshift interlock mechanism

A switch adjacent to the J-gate allows selection between normal and sport shift modes. When the latter is selected, the gearshift points are extended to make full use of the engine’s power.

New XJ driveline

• New-design GKN propshafts of tubular steel in a two-piece configuration with a central universal joint. The joint’s low-friction splines provide compliance and a smooth reaction to movements within the driveline system. Weighing a reduced 22 pounds, the new propshaft contributes to the XJ’s lightweight vehicle strategy. The forward shaft provides collapsibility in a collision, contributing to the XJ’s impressive safety performance
• The XJ’s final drive unit is new and designed especially for low maintenance and low weight. It features a lightweight (65 lb) cast iron casing with an aluminum rear cover. It is filled for life with 1.4 quarts of synthetic gear lube. The final drive ratio is 2:87:1 for both 4.2-liter AJ-V8 variants
• The XJ features unequal length halfshafts fitted with high-torque-capacity constant velocity joints at each end

VEHICLE DYNAMICS

Mike Cross, Chief Engineer, Vehicle Integrity, Jaguar Cars

New front and rear suspension systems – with the refinement of standard air suspension and enhanced CATS adaptive damping – take ride comfort and vehicle handling to new levels in the new Jaguar XJ. The new suspension systems incorporate extensive lightweight materials and are designed to complement the light but very stiff aluminum body.

The stiff structure provides a rigid foundation for handling, steering and braking performance, ensuring optimal performance of the XJ’s highly capable chassis sytems.

The new Jaguar XJ chassis features include:

• The comfort and sophistication of air suspension on both models
• Enhanced Computer Active Technology Suspension (CATS) adaptive damping
.
• New technologies, including an electronic parking brake and the latest generation of Jaguar’s Adaptive Cruise Control (ACC) with Forward Alert
• New front and rear double-wishbone suspension systems with isolated subframes for even greater refinement and ride comfort
• Four-channel anti-lock (ABS) and Emergency Brake Assist (EBA) systems
• Brembo brakes with steel-braided hoses as standard on the high-performance XJR
• A new Dynamic Stability Control (DSC) system that reacts to and controls both understeer and oversteer
• Specially tuned speed-sensitive power-assisted steering
• Four wheel and tire combinations (dependent on model). These include the standard 19-inch R-Performance alloy wheels and Pirelli P-Zero Rosso performance tires on the exclusive Jaguar XJR

Air suspension as standard

The XJ’s air suspension system uses air spring/damper units in lieu of the coil-spring/damper units of a traditional system. A unique top-mount feature isolates each damper from the body structure while maintaining the pressure within the spring. This design detail enhances the refinement and comfort of the XJ’s ride quality. In addition, spring stiffness increases according to payload.

A compressor located behind the front bumper beam feeds compressed air toa .16 cu ft. reservoir located in the XJ’s trunk under the spare wheel. Here, it is stored at a maximum pressure of 218 psi and distributed to the individual spring/damper units by a solenoid-driver valve block.

Height sensors at the four corners of the vehicle feed vehicle height data to an electronic control module in the trunk. On de-restricted roads, the system automatically lowers the XJ’s ride height by over 15 mm at 100 mph. This improves aerodynamic efficiency, vehicle stability and fuel economy during high-speed cruising.

The air suspension system is programmed with several additional operating modes:

• The comfort and sophistication of air suspension on both models
• Enhanced Computer Active Technology Suspension (CATS) adaptive damping
• New technologies, including an electronic parking brake and the latest generation of Jaguar’s Adaptive Cruise Control (ACC) with Forward Alert
• New front and rear double-wishbone suspension systems with isolated subframes for even greater refinement and ride comfort
• Four-channel anti-lock (ABS) and Emergency Brake Assist (EBA) systems
• Brembo brakes with steel-braided hoses as standard on the high-performance XJR
• A new Dynamic Stability Control (DSC) system that reacts to and controls both understeer and oversteer
• Specially tuned speed-sensitive power-assisted steering
• Four wheel and tire combinations (dependent on model). These include the standard 19-inch R-Performance alloy wheels and Pirelli P-Zero Rosso performance tires on the exclusive Jaguar XJR

New front and revised rear suspensions

The front suspension – along with the steering system – is mounted to the body via an isolated subframe of fabricated steel. The subframe locates the lower control-arm mountings, the engine’s

• Double wishbones of different lengths to minimize effect of changes in track and camber. Designed to facilitate optimal compliance for ride comfort, the lower wishbone features two separate arms linked by a ball joint, while the axis of the upper control arm is inclined for ‘anti-dive’ handling characteristics under braking
• Forged aluminum upper control arm with geometry optimized for straight-line stability. The control arm features two new fluid-block bushings and an integral ball joint for ride refinement
• Two-piece aluminum forged lower control arms. The lateral arm locates damper, anti roll-bar drop link and knuckle, and connects via a rubber bushing to the subframe. The forward arm locates via a ball bushing to the lateral arm and via a hydraulic bushing to the subframe for improved vibration damping and refinement
• Stiff, swan-neck knuckle. This aluminum squeeze casting with integral steering arm and press-fit lower ball joint, locates the brake disc shield (riveted) and brake caliper, and houses a third-generation wheel bearing with integral ABS. The supercharged Jaguar XJR uses a unique knuckle design to accommodate its larger brake discs
• Tubular anti-roll bars, tuned for the specific dynamic requirements of each model, are mounted to the front of the subframe

Rear suspension elements include:

• Double wishbones of lightweight cast aluminum. The upper control arm houses a cross-axis rubber bushing and integral ball joint. The lower control arm locates the air suspension spring/damper unit – directly tapped into the casting – and anti-roll bar drop-link. It also houses a cross-axis joint and rubber bushing
• Cast aluminum wheel knuckles with an integral toe-link arm. The knuckle locates the upper ball joint, lower control arm, riveted brake disc shield, brake caliper, ABS sensor, toe control link and a press-fit cartridge bearing. The knuckle of the Jaguar XJR is unique due to the larger brakes necessitated by its performance capability
• Toe control links facilitate toe settings independently for each wheel
• A higher roll center than the previous generation XJ gives enhanced ride comfort
• New tubular, larger diameter anti-roll bars are specifically tuned for each XJ derivative

Enhanced Computer Active Technology Suspension (CATS)

CATS optimizes ride refinement under all conditions with two-stage adaptive damping under electronic control, but is so refined that the driver is unaware that damping conditions are changing.

Benefits of the enhanced CATS system include:

• Automatically optimized ride and handling under all conditions, maximizing comfort, handling and driver control
• Refined ride comfort for normal driving with softer damper setting
• Automatic recalibration of all four dampers to stiffer sports handling when road conditions demand
• Automatic change to stiffer sports handling when cornering, as with the original CATS system, but now with the inner wheels allowed to return to softer settings mid-bend, giving improved ride comfort and increased tractability from the rear wheels
• Automatic change to stiffer sports handling when braking. CATS also now allows the dampers to return to their soft setting earlier by continually monitoring the brake switch and instantaneous deceleration rate, unlike the original system, which remains stiff regardless of the deceleration rate during the remainder of the stop. This reduces harshness of road inputs during braking
• Automatic switching of the rear damper settings slightly ahead of the front pair at low speed to reduce transient understeer, giving improved agility and turn-in performance
• Automatic switching of the front damper settings ahead of the rear at high speed to increase transient understeer, giving improved stability

CATS dampers have two sets of characteristics, governed by the same electronic control unit (ECU) that controls the air suspension system. Sensor inputs are provided by vertical accelerometers on the bulkhead and in the luggage compartment, a lateral accelerometer within the under-hood engine control module house, and a brake switch. The ECU automatically adjusts the damper settings in microseconds to suit driving conditions, thereby optimizing ride and handling.

The result is a unique combination of agile handling, outstanding ride comfort and driver control that complements the performance capabilities and luxury character of the new Jaguar XJ.

New electronic parking brake

Eliminating the old parking brake lever frees even more space for occupants. The new electronic system operates automatically, activating when the ignition key is removed. The parking brake is also configured to release automatically when the vehicle is shifted into gear to be driven off.

The electronic parking brake can be operated manually if required by pulling the switch upwards to engage or down to disengage. Should the brake be applied when the vehicle is in motion, an audible and light warning will be activated to alert the driver. The system operates via an electrical actuator mounted on the rear subframe, which pulls cable connected to the rear brake calipers.

New braking system and electronic driver aids

On the XJ8, the braking system comprises 12.6" diameter, 1.18" thick ventilated discs, fitted with two-piston floating aluminum calipers at the front. 11.3" diameter, .79" thick ventilated discs, fitted with single, floating aluminum calipers and 1.69" pistons are used at the rear.

New XJs features a bulkhead-mounted vacuum booster, designed for engine-bay venting for improved refinement. This ensures that the discs and calipers operate at maximum efficiency and contributes to responsive pedal feel under all driving conditions.

Assured stopping: Four-channel ABS with Emergency Brake Assist (EBA)

EBA helps the driver in an emergency when maximum power isn’t being applied. Often in emergency braking, the driver does not press the brake pedal hard enough and, if this occurs, EBA steps in to help. New travel and pressure sensors on the booster and brake master cylinder sense emergency braking by assessing the urgency with which the driver hits the brake pedal. Maximum available braking power is then instantly applied.

Brembo brakes for XJR

At the front, 14.4" x 1.26" ventilated discs are mated with Brembo aluminum, four-piston monobloc calipers embossed with the Jaguar R Performance logo. Solid rear discs (13" x .59") are fitted with aluminum two-piece, fixed, opposed four-piston calipers. The parking brake has a single-piston floating caliper.

The new Jaguar XJR recorded stopping distances of 118 ft from 62.5 mph to zero in testing. This was up to 14 percent more efficient than key luxury competitors and is another advantage of the XJ’s lightweight vehicle architecture.

Traction control

Traction control uses ABS system components to apply brake pressure selectively to individual rear wheels to prevent wheelspin. The system can also intervene by reducing engine torque or, dependent on conditions, a combination of both methods.

Dynamic Stability Control suppresses understeer and oversteer

DSC system uses active wheel-speed sensors at each wheel, a yaw sensor, a lateral acceleration sensor and a steering angle sensor to monotor the vehicle’s movement in relation to the driver’s inputs. The system also monitors brake system pressure and engine torque.

If the system perceives that the driver’s intended direction does not match that of the vehicle, it intervenes by applying brake force to any required combination of the four wheels.

Should the vehicle oversteer for example, with the rear wheels sliding out in a cornering maneuver, DSC applies the outboard front brake to correct the yaw moment and stabilize the vehicle handling. In an understeer situation, in which the front wheels tend to plow forward instead of turning the vehicle, DSC applies brake pressure to the inboard rear wheel to help correct direction.

In emergency steering maneuvers that threaten to put the vehicle at the limits of its grip, DSC can intervene to reduce the danger of loss of control. In addition, excessive engine torque that causes understeer or oversteer behavior can be counteracted by DSC.

The DSC system operates automatically, but can be manually switched off by the driver. When switched off, a warning illuminates.

The DSC ECU features increased processing power. It facilitates the use of more sensors to monitor vehicle operations and with greater measuring precision and actuates the hydraulic modulator that controls brake system intervention.

Steering precision

The speed sensitivity of the steering sytem is precisely calibrated for each engine and suspension combination of the new XJ. The Servotronic ‘curve’ controls the relationship between the steering effort and the vehicle speed by applying an opposing hydraulic reaction force to raise efforts as the vehicle speed increases. The system also ensures Jaguar XJ’s effortless low-speed maneuverability for the ease of parking.

Jaguar XJ wheel and tire range

• The XJ8 is equipped with 7.5 x 17 inch "Elegant" alloy wheels in a 10-spoke design, fitted with 235/55R17 tires
• Optional on the XJ8 are the 8 x 18 inch "Dynamic" alloy wheels in an 8-spoke design, fitted with 235/50R18 tires
• The XJR features 8.5 x 19 inch R-Performance alloy wheels with 255/40R19 performance tires. These feature an asymmetric design with wide longitudinal channels for uncompromised dry and wet handling, refinement and ride comfort. The tread pattern is divided laterally into three distinct elements, each designed for a particular aspect of performance and ranging from a robust outer shoulder through a semi-slick central rib with curved transversal grooves to a more open inner shoulder
• A 20 inch BBS two-piece alloy wheel, the "Sepang," fitted with 255/35R20 tires, is also available as a special order option

Jaguar Adaptive Cruise Control (ACC) with Forward Alert

ACC was pioneered on Jaguar’s XK8 sports car in 1999 and uses microwave radar technology to overcome the need for the driver to adjust speed – either by disengaging cruise control manually or applying the brakes – when approaching slower traffic on the road ahead. Instead, ACC automatically adjusts the throttle – and may also apply limited raking – to reach a speed that is compatible with traffic ahead.

The ACC microwave radar sensor – which weighs less than 2.2 lbs – takes 40 individual measurements on each horizontal scan to maintain a constant watch over traffic conditions. Other systems make far fewer measurements.

ACC now also features Forward Alert, which provides an audible warning of slowing traffic ahead but does not intervene by adjusting the throttle or applying the brakes. Forward Alert uses the same radar sensors.

SAFETY AND SECURITY

David Scholes, Chief Program Engineer, Jaguar XJ

The new XJ features a comprehensive array of safety technologies, including Jaguar’s sophisticated Adaptive Restraint Technology System (A.R.T.S.). But at its protective core is the strong body shell that is the result of its lightweight vehicle architecture.

The new Jaguar XJ’s aluminum-intensive body structure has already proven its strength in the crash-testing laboratory. Lighter than the equivalent steel body, the XJ body structure carries significantly less kinetic energy into a collision, reducingt the amount of energy that must be absorbed by the body in an accident.

"Our target in developing the new Jaguar XJ was to produce one of the world’s safest cars," comments David Scholes, XJ Chief Program Engineer. "And the body structure is the foundation of its excellent safety performance."

Sophisticated crash-modeling computer techniques

The new XJ has excelled in Jaguar’s internal testing, undergoing numerous frontal, side and rear impact tests. Prior to the first XJ prototype crashing into a barrier, Jaguar engineers performed more than 500 computer-simulated crash events using sophisticated crash-modelling software.

Jaguar’s internal testing simulates real-world accident situations, in the same way as the independent Euro-NCAP and US-NCAP testing programs. The new XJ will be one of the first vehicles designed to meet the more stringent U.S. crash performance standards (FMVSS208) introduced during 2003.

Key features of the XJ’s protective bodyshell structure

• Excellent side impact protection, resulting from a very strong center pillar with a wide, tapered base, extruded aluminum lateral floor reinforcements, and door beam extrusions
• A magnesium cross-car beam provides an ultra-stiff foundation for the facia, anchoring the steering column and providing a firm base for the operation of the driver and passenger air bags. The instrument panel features foam bolsters specifically designed to protect front-seat occupants’ knees from injury
• Front and rear crush zones n the body structure absorb crash energy progressively while protecting the integrity of the cabin
• A ‘tube-in-tube’ design propshaft provides built-in crush properties that absorb collision energy

A.R.T.S. – The science of safety technology

A.R.T.S. has the capability to sense the severity of a collision and deploy the vehicle’s passive safety systems according to type and magnitude of collision. As a result, the system optimizes restraint protection for vehicle occupants, reducing the risk of air bag-induced injuries. A.R.T.S. also serves to reduce unnecessary passenger air bag deployments, thereby reducing the cost of accident repairs.

Key elements of A.R.T.S. include:

• Occupant weight sensing – A.R.T.S. uses a seat-weight sensing system to detect whether the front passenger seat is occupied and the weight range of the occupant. If the seat-weight sensor detects a small and/or lightweight occupant is in the passenger seat, it deactivates the passenger airbag and illuminates a warning light to inform the driver
• Occupant position sensing – Four ultrasonic detectors within the passenger compartment monitor the position of the front-seat passenger. A seat-track position sensor determines the driver’s position relative to the steering wheel. In conjunction, the system monitors the front occupants usage of their safety belts. The sensors are constantly in communication with the Restraints Control Module (RCM), the electronic brain of A.R.T.S
• Crash sensors – Rapid response to a collision is central to the advanced capabilities of A.R.T.S. Six crash sensors are positioned around the vehicle structure, the sensors communicating with the RCM. This determines the type and severity of the collision and deploys passive safety technology – safety belt pretensioners and air bags – according to the protection required
• Duel-stage driver and passenger front air bags – The air bags are capable of two levels of deployment, a lower pressure first stage and a higher pressure second stage, depending on type and severity of the collision and the occupants’ position. The driver air bag, which deploys from within the steering wheel center cover, is 57 liters in capacity. The passenger air bag, which deploys from the fascia is approximately 110-120 liters in capacity
• Side air bags for front-seat occupants – Mounted in the outboard side bolster of the front seats, the new XJ’s thorax airbags deploy in the event of a side impact
• Side air curtains – Designed to protect front and rear occupants in the event of a medium-to-high side impact, the side air curtains deploy to cover the window area of both doors. They fill to their 18-liter capacity in less than 30 milliseconds and are approximately 2.76" thick when fully inflated
• Energy absorbing heat system – Both front seats are equipped with energy absorbing backrests designed to reduce the likelihood of whiplash-style neck and spine injuries in a rear impact. The system is triggered by the weight of the occupant being forced by collision energy into the seatback. The backrest is designed to move rearwards but remain upright for a distance of about 2 inches, and then tilt rearward. The combined effects of these two movements absorbs impact energy and reduces the relative acceleration of the head and body
• Three-point safety belts – Fitted to all occupant positions, each belt is equipped with a pyrotechnic pre-tensioner. The front seats also incorporate load-limiting retractors
• Beltminder – A safety-belt use monitor senses whether the front seat occupants have fastened their safety belts. If a belt has not been fastened and the vehicle exceeds 10 mph, the Beltminder system activates an intermittent warning tone and warning lamp
• Steering column – The steering column is capable of collapsing by just over 3 inches in a collision to enhance the protection provided to the driver from the front air bag. Its collapse mechanism is designed to ‘ride down’ at a predetermined crash load

Comprehensive security systems

Engine immobilization system

The sophisticated engine immobilization system is integral with the engine management system, shutting down all fueling ignition and cranking functions. A uniquely coded transponder is located in the ignition key head to individually identify the key. Over 34 billion code combinations are available and include encrypted data for security against copying.

Security on the new XJ extends beyond the electronics systems. The doorframes are a case in point being designed to resist the attempts of the most determined thief to lever them away from the body in an attempt to forcibly enter the car.

Integrated key transmitter

The engine can only be activated by inserting the ignition key, which initiates a sophisticated decoding process to validate the transponder code. This involves three-way communication of a coded algorithm between the instrument cluster, engine control module and key transponder. The agreement of all three systems on the transponder coding is necessary before the engine will start.

Additional security features include:

• Perimeter sensing of doors, hood, and trunk, the vehicle alarm sounding if they are tampered with
• A master locking switch located on the center console can be used to prevent uninvited entry when stationary at road junctions and traffic lights (if drive-away locking has been overridden by opening a door.)
• Central locking by key, remote transmitter and interior handle
• Drive-away locking ensures all doors lock automatically when the vehicle travels at speeds above 5 mph. If the vehicle stops and a door is opened, provided the engine remains running, the door will re-lock when closed and the vehicle is moving. This feature can be disabled, or reinstated, by a Jaguar dealer as required
• Panic alarm. The vehicle alarm is activated by pressing the panic button on the key transmitter three times within three seconds, when in or near the car
• Two-stage unlocking enables only the driver’s door to unlock on the first operation of the key or remote transmitter. Passenger doors are unlocked with a second operation
• ‘Smart’ locking helps to ensure that the vehicle is fully secure when locking takes place. If one of the doors, the trunk, or the hood is open when an attempt is made to lock the vehicle using the key transmitter, the vehicle will not lock. The direction indicators will flash five times and the horn will ‘chirp’ twice to inform the owner that the vehicle is not secure
• Security-coded audio system with unique faceplate design. A full alarm action is invoked if the radio is removed
• Headlight convenience. Pressing the button on the key transmitter illuminates the headlights for a period of 25 seconds
• The tamper-resistant odometer is an LCD display, with the numbers encrypted and stored in the vehicle’s electronic microprocessor software. The odometer memory position is protected by an anti-tamper algorithm which provides a high degree of resistance to tampering or ‘clocking’
• Gearshift interlock system. On both models, the transmission lever may only be moved from the ‘Park’ position if the ignition/engine is switched on and the foot brake is applied
• A visible vehicle identification number (VIN) plate is located at the base of the windshield. Screen replacement is required to remove it

ENGINEERING AND PRODUCT DEVELOPMENT PROCESS

David Sholes, Chief Program Engineer, Jaguar XJ

An all-new, world-class luxury sedan, the Jaguar XJ pioneers a new lightweight vehicle architecture that represents a major step forward in aluminum-intensive automotive body structures.

Jaguar’s engineers have developed a conventional monocoque body structure of aluminum rather than relying on a less efficient space-frame construction. As such, the new XJ moves the automobile industry forward in its drive to reduce weight and enjoy the wide range of benefits this offers in terms of performance, fuel economy, emissions, crash safety, vehicle dynamics, and recyclability.

The Jaguar XJ’s body structure uses pressings of sheet aluminum combined with aluminum alloy extrusions and aluminum castings. Jaguar’s engineers adopted proven construction techniques of the aerospace industry to assemble this structure, making extensive use of rivet-bonding. Rivet-bonding uses self-piercing rivets and aerospace-style epoxy adhesives to create a structure of remarkable strength and light weight.

The creation of this lightweight vehicle architecture required high levels of precision and engineering craftsmanship that Jaguar is uniquely positioned to deliver.

Born of state-of-the-art engineering technology and processes

"Computers don’t engineer cars, people do," says David Scholes, XJ Chief Program Engineer. "Our tools are designed to enable every member of our engineering team to achieve the excellence that is the hallmark of Jaguar."

Product information management

CAD, CAE, and CAM tools are used in a wide variety of ways within Jaguar, as well as by supplier companies. PIM was the unifying factor for the individual elements of the development process, giving every member of the XJ program team access to the information they needed, no matter where they happened to be located.

Equally as important, PIM enabled engineers to see exactly how any component modifications would impact on the work of their colleagues, this ensuring the best possible quality of fit between components and optimum functionality.

Single data model

Engineers were able to access this single data model at any time, regardless of their location, through the Jaguar intranet. With so many parties having ready access to such huge amounts of data, only one person was authorized to modify the design of a single component. All relevant personnel, including key suppliers, were automatically notified of changes as soon as the information was stored, and the system informed them of the necessity to update their own designs in order to maintain compatibility with interacting components. In this way, engineering teams worked collaboratively and concurrently, toward common goals.

Knowledge Based Engineering

KBE capitalizes on Jaguar’s institutional knowledge, passing on ‘lessons learned’ to help engineers continuously hone their designs with predictable success. It also soaks up newly acquired knowledge, which proved an especially valuable tool as Jaguar engineers worked to create the XJ’s rivet-boded, aluminum-intensive body structure.

KBE was used extensively in the development of the XJ, including its body-in-white and component packaging. The technology was also used to create an "interactive software mannequin" that was used to prove out the XJ’s interior roominess and occupant ergonomics.

Digital buck: the first new Jaguar XJ visualized on the computer screen

Solid modeling provided a more complete representation than could be achieved either with wire-frame or surface models, and enabled engineers to make design changes, perform analysis and evaluate the results of a change, more quickly than ever before. In addition, detailed motion studies could be carries out to simulate and analyze, for example, wheel and suspension movements and the opening and closing of doors and windows. As a result, far fewer, real-life prototypes were needed, dramatically condensing development lead-time, while improving the accuracy and quality of physical prototypes.

Rapid prototyping

Rapid prototyping uses the digital ‘blueprint’ of the component to create the physical model. Such processes include stereolithography, Fused Deposition Modeling (FDM) and Selective Laser Sintering (SLS)

Jaguar maintains in-house FDM equipment, which is ideal for prototyping interior trim, vents, door deals and engine components. It also allows the creation of packaging models, which help engineers visually model the amount of space needed for a switch or handle, for example.

Creating a rapid prototype part takes only a fraction of the time – sometimes only overnight – that is needed to model in the traditional way. This helps to cut weeks from the development process.

Virtual Manufacturing: The new XJ was first built in virtual-reality

Highly sophisticated ‘virtual manufacturing’ tools were used to design each step of the Jaguar XJ’s assembly process. Linked integrally with Jaguar’s PIM toolset, the digital virtual manufacturing tools helped production engineers to configure both the Castle Bromwich (body assembly) and the Browns Lane (final assembly) plants that produce the new XJ.

Simultaneously with the engineering of the vehicle itself, production engineers used the EDS Factory CAD digital tool to create a detailed model of the assembly process. This tool helped to hone the design of the assembly systems and equipment – using virtual models of floor and overhead conveyors, cranes, operators, material handling containers and robots – more quickly and accurately than would have been possible using conventional methods.

Traditionally, an assembly plant would be configured after the design of the vehicle itself, using specially built prototypes to work out assembly processes and build sequences. The digital system is also quicker. Because it is linked directly with the digital design of the vehicle itself, the assembly process can keep pace with any subsequent detailed engineering changes.

With the new ability to replicate the real-life environment of an assembly plant digitally, Jaguar was able to prove out key assembly processes well in advance of production starting.

The human factor: operator ergonomically honed digitally

This detailed design study helped create individual work stations throughout the assembly operations. Each worker’s function was ‘modeled’ to ensure that the job could be done comfortably by various human statures. As a result, work station heights and individual build processes were shaped for optimal ergonomic performance, which makes the process ideal for the creation of high quality, luxury cars.

Quality processes

Advanced Quality Planning (AQP) A key quality technique employed by Jaguar is Advanced Quality Planning, a structured methodology that optimized product quality by identifying potential problems and ‘designing out’ the issue so that it never arises. The technique covers all stages of development, from early Computer-Aided Engineering (CAE through to Statistical Process Control (SPC) of production processes. Anything that might eventually result in a potential problem from a squeak or rattle to a major system failure is identified and eradicated at a very early stage. Robustness Design robustness takes into account a wide range of variables that fall into two main categories: ‘control factors’ and ‘noise factors’. Control factors are those over which a design engineer has complete control; they include, for example, material specification, surface treatment and dimensions.

Noise factors however are influences beyond the direct control of the design engineer, but to which the system or component must be made insensitive. They are divided into the following types: piece-to-piece variation; change in component dimensions over time; external and internal environment; and customer usage – the way the customer uses and interacts with the car.

As a car selling across the world – like all Jaguars – the new XJ will encounter a wide range of noise factors, all of which could contribute to unacceptable levels of degradation over time if the vehicl