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Audi RoadJet Concept
Debut in Detroit: Audi is taking the wraps off a study car by the name of Roadjet Concept at the North American International Automobile Show. A vehicle that blends the latest evolutionary stage of Audi's formal idiom with an entirely new space concept. The drive technology, too, represents a new departure: on the 300 bhp 3.2 FSI engine, innovative concepts produce an unprecedented synthesis of performance, liveliness and efficiency. In conjunction with a longitudinally installed engine, the Audi Roadjet Concept is moreover the first model to feature the sporty 7-speed Direct Shift Gearbox.
The study car furthermore serves as a technology demonstrator of innovative electronic systems that will be finding their way into production models in the next few years.
The introduction of a new cross-manufacturer standard for car-to-car communication opens up a new dimension in safety and service. Important parameters such as safety, the traffic flow and therefore obviously also fuel economy and emissions can be influenced positively by information exchanged directly between vehicles in moving traffic. A car-to-car communication standard furthermore opens up countless new possibilities in the domains of service and comfort.
One particular innovation that enhances driving fun is Audi drive select: this system enables the driver to preselect several entirely independent vehicle characteristics at the push of a button.
Three modes – "comfort", "dynamic" and "sport" – alter the steering, damping and transmission response, as well as the engine map. Audi drive select thus provides access to highly distinct driving experiences that can be realised by a single vehicle, entirely as the driver sees fit.
Design
The exterior
The styling of this four-door fastback saloon is a new, distinctive interpretation of Audi design. Measuring 4.70 m in length and 1.85 m in width, the Audi Roadjet Concept respects the standard dimensions of a B-segment vehicle. However, its height of 1.55 m and the wheelbase of 2.85 m result in substantially greater spaciousness, and also give this car fundamentally new basic proportions.
The decidedly short overhangs at the front and rear give the Roadjet Concept an utterly new flavour of sporting flair.
The characteristic features of the front end are the dynamic tapered shape with the characteristic Audi integral single-frame grille and the large air inlets below the bumpers. Vertical slats in the single-frame grille support the prominently three-dimensional Audi badge. Concave surfaces around the highly sculpted wheel arches lend the nose extra width. Beneath the clear-glass covers of both the headlights and the rear lights, LED light units create an unmistakeable visual impact both in daylight and after dark.
The high shoulders that lend the vehicle an air of power and safety are also typically Audi. The Audi Roadjet Concept moreover has a large window area, reinforcing the impression of light and spaciousness inside the vehicle.
Slim roof posts and the raked rear window combine with the coupé-like roof line in producing a highly dynamic silhouette. A roof spoiler above the large rear window helps to maintain good surface contact, while visually extending the arc of the roof even further to the rear.
The dynamic line above the sill, as well as the shoulder line, defines clearly horizontal overall proportions that are emphatically road-centred. A new element to Audi is the arched capping line, extending between the front and rear wheel arches.
Together with the shoulder line, it produces an invigorating interplay of convex and concave surfaces.
The handles are integrated flush into the door surfaces; they are extended when touched, to allow convenient opening of the doors.
The impression created by the rear end, too, is decidedly dynamic: wide wheel arches, the trapezoidal tailgate and the diffuser below the bumper emphasise the sporty character of the Audi Roadjet Concept. The stepped rear lights extending well round into the sides echo this car's closest relations in design terms within Audi's current production range: the Avant models and the Sportback. The tailgate beneath the windows likewise extends well round into the sides, thus acting as a visual bridge between the rear and sides. The exhaust system's wide twin tailpipes, integrated into the striking diffuser, are another new element.
The interior
Modernity and functionality, dynamic elegance and open perspectives: this is the most immediate impression of the Audi Roadjet Concept's interior. Warm, subdued earth colours contrasting with the light grey of precision metal applications create an atmosphere pitched somewhere between elegant functionality and emotional appeal. This impression is enhanced by the combining of purely functional materials such as Neoprene, at floor level, with exclusive leather.
This vehicle interprets the architecture of the Audi interior in a novel way. The characteristic features include the stimulating interplay of proportions and dynamism. The instrument panel envelops the driver's and front passenger's seats in a wide, horizontally split arc. The controls and displays in the dash panel and on the centre console come across on the one hand as organically integrated and on the other as neatly structured and functional.
The four individual seat pans, almost filigree in appearance and featuring integral head restraints, divide up the interior into four separate zones. Between the rear seats there is a system of rails that can accommodate options that include a storage box with centre armrest, an espresso machine or a baby carrier facing to the rear.
The rear seats themselves can be adjusted along diagonal rails; when opened out into their frontmost position, a centre child's seat can be installed obliquely behind the rear seats if required. This centre child's seat is guided on rails on the movable luggage compartment floor. It can be folded over and easily removed to the rear.
The load area can be further enlarged by folding the rear seat backs forward. The electrically operated movable load area floor pivots automatically to the rear, beyond the bumper, appreciably facilitating loading of the vehicle. The rail system integrated into the load area floor incorporates lashing points that can be used to secure the child seat or lash down items being carried, before the load area floor is moved forward again electrically, back into the vehicle.
The convenience function on the remote control enables the driver to extend the load area floor at the same time as the tailgate is opened.
The load area floor can be set to two positions inside the vehicle. Its lower position produces the maximum load area capacity; its normal level results in a level load area.
Both the comfortable, relatively upright seat position with ample legroom and the ample shoulder room and headroom at all four individual seats set new standards.
But superlative comfort in the Audi Roadjet Concept is not merely the result of the generous amount of space available. The deluxe automatic air conditioning with a newly developed air vent principle provides draught-free, individually variable climate control for every occupant.
A Bang & Olufsen sound system purpose-developed for the Roadjet Concept provides an audio quality worthy of the concert hall. As on the A8, 14 speakers – including the extendable tweeters on the instrument panel – and an amplifier output of more than 1,000 watts produce an acoustic experience that is without equal in the automotive world. If desired, the front and rear passengers can also listen to music via Bluetooth headphones.
The audio system also supports a new function that allows the occupants to converse without needing to raise their voices even when the car is travelling at high speeds. A technology by the name of Digital Voice Support (DVS) picks up the occupants' voices via microphones and reproduces them via the amplifier and speakers. Reproduction is controlled to take account of both the relative position inside the car of the person speaking and the general level of noise being generated by the vehicle.
The Multi Media Interface MMI has been reconfigured in the Audi Roadjet Concept. In addition to the central 10-inch display in the instrument cluster, there are separate displays and operating units for the front and rear passengers – including a 7-inch display on the backs of the front seats for the rear passengers. An entirely new technology makes its debut here: the front passenger views information on a back-projection display on the instrument panel, which also allows them to watch TV while the car is moving. To avoid distracting the driver, this display is screened off by a shield that extends automatically out of the instrument panel.
The range of functions is moreover tailored to individual requirements. Functions that classify directly as vehicle operation – such as the car setup menu – can be operated exclusively by the driver. On the other hand, the passengers can control both the infotainment system and the navigation, so that they can assist the driver with route suggestions, for instance.
The Roadjet Concept does not have traditional sun visors; instead, this function is performed by the use of Vari-Light technology along the upper edge of the windscreen: the degree of transparency of the glass – and therefore of light screening – can be varied electrically, thus enabling the driver to prevent any undesirable glare.
There is a further convenience feature in the rear centre armrest. On the Detroit showcar, it incorporates an espresso machine complete with water reservoir, stable cup holders for four cups and accessories. The occupants can now always enjoy a fresh cup of coffee whenever they wish, for instance during a break or while sitting in a tailback – an enticing alternative to lukewarm beverages out of a flask, and one that is bound to appeal not just to coffee connoisseurs.
Drivetrain
Typically for an Audi study, the Roadjet Concept too is powered by an engine that heralds the shape of things to come with its innovative technology. This applies in equal measure to the 300 bhp evolutionary version of the 3.2 six-cylinder FSI engine and the sporty Direct Shift Gearbox in conjunction with quattro permanent four-wheel drive.
The 3.2 FSI V6 with Audi valvelift system
The 3.2 V6 FSI – which features as a basic engine with an output of 255 bhp in the Audi A8, A6 and A4 – displays all the characteristics of an ultramodern petrol engine: FSI petrol direct injection with demand-controlled fuel supply, four valves per cylinder and highly effective exhaust emission control.
FSI engines develop superior power and dynamism to conventional units with indirect manifold injection – and they do so with a very high stand¬ard of fuel economy. With this remarkable achievement, Audi is opening up a new dimension in the efficiency of standard petrol engines, demonstrating once again the brand’s proverbial “Vorsprung durch Technik”.
The FSI petrol direct injection system confirmed its unique potential in what must be the most challenging endurance test in the world: a power unit with FSI direct injection drove the Audi R8 to victory on four occasions in the Le Mans 24 Hours.
The evolutionary version that powers the Roadjet Concept includes two technologies that double the specific advantage of FSI technology. Because with a fixed intake manifold together with integral vacuum reservoir – as opposed to the variable intake manifold of the production version – the 3.2 FSI can be configured systematically as a sports engine.
The six-cylinder engine in addition features a new valve control principle by the name of Audi valvelift system. In the form of two-stage cam lift adjustment, it is able to vary the degree of valve opening according to load and engine speeds.
What this means in practice is that in flowing traffic, the engine produces a decidedly smooth, relaxing response to only moderate use of the accelerator pedal, with impressive pulling power in reserve that results in outstandingly low fuel consumption.
But as soon as the driver ups the tempo, the 3.2 engine reveals its qualities as a highly talented athlete. It responds with bite to even minimal movements of the accelerator and moves fleet-footedly right up to the speed dictated by the limiter, which only cuts in at 7,500 rpm. What is particularly remarkable is that the power output rises constantly virtually all the way up to that point.
This V6 engine delivers its maximum output of 220 kW (300 bhp) at 7,000 rpm; its peak torque of 330 Nm is available at 4,500 rpm. The Roadjet Concept 3.2 FSI accelerates to 100 km/h in 6.4 seconds, and its top speed is electronically governed at 250 km/h.
No less astonishing is the average fuel consumption of this evolutionary concept: the Roadjet Concept covers 100 kilometres on just 10.4 litres of Super Plus – despite the Roadjet Concept's higher weight and larger frontal area, this figure is a few tenths of a litre better than its production counterpart in the A4 3.2 quattro, which develops 45 bhp less!
The combination of FSI and Audi valvelift system unquestionably demonstrates how much potential Audi's petrol engines of the future will still be capable of mobilising, with a view to delivering even more driving fun and efficiency. And that future is not far off: the underlying technology is already so mature that it could start finding its way into production in a few months' time.
The sporty 7-gear Direct Shift Gearbox
The Audi Roadjet Concept is the first Audi model to feature a sporty Direct Shift Gearbox with twin clutch in conjunction with a longitudinally installed engine. It combines the advantages of a 7-speed manual gearbox with the qualities of a modern automatic transmission, thus providing a drive concept superior in every respect. The driver benefits from supreme agility and driving pleasure combined with harmonious and dynamic acceleration without interruptions to the flow of power from the engine.
This is coupled with good economy thanks to low fuel consumption, and convenient operation.
The basis for this new development is a three-shaft 7-speed manual gearbox which offers considerable variability in the selection of the transmission ratio. Thanks to the use of a twin multi-plate clutch with ingenious electro-hydraulic control, two gears can be engaged at the same time.
So how does the Direct Shift Gearbox work? During dynamic operation of the car, one gear is engaged. When the next gearshift point is approached, the appropriate gear is pre-selected but its clutch kept disengaged. The gearshift process opens the clutch of the activated gear and closes the other clutch at the same time with a certain overlap. The gear change consequently takes place under load, with the result that a permanent flow of power is maintained.
Incorporating optimum gearshift strategies, the control logic integrated in the transmission provides instantaneous, comfortable and smooth gearshifts that are virtually free of any jolts or judder. And by moving the gearshift lever in the manual gate or operating the standard-fit paddles behind the steering wheel, as on a racing car, the driver can actively influence the choice of gears and the gearshift point at any time.
quattro permanent four-wheel drive
quattro permanent four-wheel drive is a typical feature of all high-performance Audi models. Since revolutionising the car world when first unveiled 26 years ago, permanent four-wheel drive has long since found its way into virtually all vehicle categories – and not just at Audi. Almost one in three Audi cars sold is currently a quattro; by the end of 2005, around 2.5 million Audi vehicles with quattro permanent four-wheel drive had been built.
quattro ensures excellent traction and lateral stability and minimises the effect of propulsive power on the vehicle’s self-steering properties. This is a precondition of the car's tremendous cornering speeds and high dynamic stability.
A Torsen differential in the new Audi Roadjet Concept – with its longitudinally installed engine – automatically ensures the optimum distribution of power between all four wheels.
The name Torsen is a combination of the terms “torque” and “sensing”. The Torsen differential is a self-locking worm gear.
The advantage of this is that the locking action is only prompted by the driveline. Yet this type of differential accommodates differences in speed when the brakes are applied and when cornering. The power is normally split 40:60 between the front and rear axles, producing particularly dynamic self-steering behaviour. In extreme cases, up to 80 percent of the propulsive power can be diverted to one pair of wheels if slip is encountered.
Chassis
The Audi dynamic suspension layout of the Roadjet Concept is based on proven sports technology: the refined four-link front suspension acknowledged as a typical Audi feature, and the self-tracking trapezoidal-link rear suspension carried over from the Audi A8 and A6. The 20-inch wheels with size 245/45 R20 tyres are an impressive feature.
All this results in a driving performance that stands up to any comparison in respect of dynamism and which sets the standard with regard to ease of control, even on rough terrain. This is also due in no small measure to the speed-dependent servotronic power steering featured as standard, supplementing the precise handling of the Roadjet Concept with even more sensitive steering precision.
Audi dynamic steering makes its first appearance on an Audi car; this superimposed steering system adjusts the steering ratio as a function of road speed. It affords a smoother ride at high motorway speeds in the form of a more indirect ratio, coupled with directional stability that is resistant to slight movements. When the Roadjet Concept is driven sportily on winding roads, on the other hand, a more direct ratio that permits high steering precision and a swifter response by the driver represents the optimum.
Another new feature is the electronically adjustable dampers that cover a variety of characteristics ranging from comfortably soft to sportily firm.
Electronic systems
As a technology demonstrator, the Audi Roadjet Concept embodies the proverbial "Vorsprung durch Technik" not merely in its drivetrain. It comes complete with a raft of other systems that will be finding their way into series production in a few years' time, thus paving the way for driving fun, safety and comfort.
Audi drive select
Only a minority of car owners can afford the luxury of having three cars parked in front of their house to give them maximum flexibility in choosing the right car for every occasion, depending on whether comfort, manoeuvrability or dynamic behaviour is what they require. The Audi Roadjet Concept fulfils all these requirements in a single car. Because Audi drive select allows the driver to preselect three highly distinctive configurations for the engine, transmission characteristic, steering and shock absorbers. The result is a car that can be enjoyed in three utterly different ways.
The basic setting is the "dynamic" mode; it is activated automatically at the start of every journey, and its overall concept reflects the expectations that Audi drivers typically have of what their car should feel like to drive in terms of both dynamism and comfort. The driver is informed which mode is currently active via the centre display in the instrument cluster.
If the driver selects the "comfort" mode by pressing the button on the control in the steering wheel, the shock absorbers adopt noticeably softer settings in order to filter out bumpiness in the road surface even more effectively. The Servotronic requires lower steering forces, and dynamic steering establishes a more indirect spectrum of ratios. The engine and transmission respond gently to use of the accelerator. This setting is perfect for relaxed driving over long distances, above all on straight roads such as motorways.
The "sport" mode, on the other hand, lends the Audi Roadjet Concept a decidedly sporty driving feel. The shock absorbers now adopt a firm response and the steering ratio is direct. The engine responds more spontaneously to the throttle and the transmission's shift points move higher up the engine speed range: the ideal basis for active driving pleasure on winding roads.
Over and above the three basic configurations, Audi drive select provides scope for varying individual parameters between the levels dynamic, sport and comfort. It is for instance entirely possible to combine sporty shock absorber settings with a relaxed, easy-action steering response.
Car-to-car communication
The electronics developers have focused on safety and traffic control in the Audi Roadjet Concept, as well as on driving pleasure. It features a prototype of a future generation of information-processing systems that herald in a new era in road traffic networking specifically in countries with high volumes of traffic.
At the heart of this concept is car-to-car communication, meaning the direct exchange of information within the flow of traffic. Unlike the telematics systems of the recent past, no central service is now needed to consolidate and process the information swiftly and effectively.
The progress that has been achieved in the areas of computing power and software development have made this application possible; even though they occupy very little space and consume very little energy, future systems will be capable of processing an array of data into practical, easily digested information for the driver that moreover paves the way for a very high standard of safety.
The reality of road traffic means that the car-to-car network can of course only be activated with a certain lead time. This hurdle is, however, manageable because virtually all vehicle manufacturers in Europe, the USA and Japan have agreed in parallel to develop a common standard for the hardware and software.
Applications have also been submitted to the authorities to use standard radio frequencies on an international scale, thus assuring the system's proper functioning when driving abroad.
Once all new vehicles in a market are being factory-fitted with this new technology, a functioning network of car-based transmitters will be created within a few months, at least in conurbations.
Many new areas of application can then be exploited in practice. The following three examples are intended merely as illustrations of what scope car-to-car communication offers:
Example 1 – safety.
A vehicle has skidded on a slippery surface on a blind bend and is hanging half in a ditch, at right-angles to the flow of traffic. It is now unable to move unassisted. Other vehicles are swiftly approaching the obstruction but their drivers are unable to see it. With the new communication technology, the stranded vehicle will transmit a warning signal which – thanks to the network established with the vehicle's on-board navigation system – also indicates the location of the hazard. A corresponding warning simultaneously appears on the navigation screens of the approaching vehicles, indicating the location of the accident – the risk of a collision is thus substantially reduced.
Example 2 – traffic flow.
Lines of vehicles are moving between sets of traffic lights on a multi-lane arterial road. The cars accelerate, only to have to brake again when the lights turn red. Such a driving style is not only fatiguing for the individual driver, but also means that thousands of litres of fuel are wasted along every kilometre of such roads in the long term, by the traffic as a whole; it furthermore significantly inflates exhaust emissions in conurbations.
Car-to-car technology means that the cars are not only able to establish a network with each other, but also pick up information from static transmitters such as the traffic lights' control systems.
The phases of each set of traffic lights can thus be transmitted, giving drivers an opportunity to anticipate more accurately how much acceleration is necessary or appropriate. The same applies to impending congestion: using data from cars further ahead, the systems can recommend what speeds drivers should adopt in order to keep the traffic flowing.
Example 3 – service.
When driving through a city centre, a driver has selected the local shopping centre as the destination for the navigation system. There is a chronic shortage of parking spaces around that destination. Here too, the new technology is able to help: the mobile system uses the coordinates for the destination to link up with the parking spaces management system for the area around the destination. If a nearby vacant parking space is reported by static facilities, such as at a multi-storey car park, the navigation system can automatically take this into account and simultaneously reserve the space in that car park. The driver is guided to their destination by the shortest and most convenient route, instead of having to drive round in circles endlessly hunting for that elusive parking space.
The number of variations on these examples is almost limitless, illustrating the huge potential of the new technology in promoting safety, flexibility and efficiency as the volume of traffic on our roads increases.
source: Audi