|
Communication, comfort and convenience electronics The field of electronics has long since advanced into automotive technology. This applies in particular to the luxury segment where driver expectations regarding communication, comfort and convenience systems naturally play a very important role. The new A8 therefore offers numerous innovative technologies in this area, some of which are available for the very first time in an Audi. These include, to name just a few examples, the advanced key access and authorisation system, one-touch memory personalisation and the radar-assisted distance control system known as adaptive cruise control. However, the Audi development engineers have by no means integrated innovations into the vehicle at a functional level only. Numerous new elements have also been introduced behind the scenes, in the vehicle's electrical system. In view of a dramatic increase in the range of functions available, it was also important to guarantee operational reliability and efficient energy management. Networking played a decisive role here. Five main bus systems connect all electronic components on board the new A8. The entire driveline - including engine, transmission and brake control units - is networked via a high-speed CAN bus. The infotainment components such as MMI, sound and navigation systems communicate via a further high-speed bus based on MOST technology. The comfort and convenience components, from door controls to air conditioning, are also networked with each other. An independent "gateway" control unit acts as an interface between the bus systems. This connects the drive, comfort/convenience and infotainment networks hence making a control centre like the MMI possible in the first place. The Audi development engineers also relied on new technologies for the vehicle's wiring systems. New bus systems - such as the optical MOST technology - have been used; these include plastic-based optical fibres and foil wiring which is particularly space-efficient. Battery energy management The new Audi A8 for the first time has a no-load energy management system that independently ensures that there is always enough energy to start the engine, based on the battery charge status and the temperature. It even ensures this if the vehicle is left unused for a lengthy period. Modern vehicles are constantly tapping the battery's energy even when they are not in operation. For instance, the traffic report memory, alarm system and radio remote control's receiver all constantly consume a minor amount of current. This is particularly the case on luxury-class vehicles, which have a particularly high number of electrically powered comfort, convenience and information systems. If the A8's battery charge threatens to become critical, the energy management system reduces current consumption in the no-load status by consumers gradually shutting down. The dynamic energy management system permanently monitors the level of battery charge and the charging activity while the car is being driven. If necessary, the system for instance marginally increases the idle speed, in order to boost the alternator's charging performance. In extreme cases, the dynamic energy management system temporarily shuts down very high-consumption components such as the seat or rear-window heating. During normal vehicle operation, however, this interruption is so brief that the driver does not even notice.
Navigation system with DVD A fully digital navigation system based on the optical MOST systems has been introduced in the Audi A8 - for the first time ever in a production car. A new storage medium has also been introduced for the navigation system: a DVD has more than ten times the storage capacity of conventional CD ROMs and a significantly faster read access time. Almost the entire road network of Western Europe can now be stored on a single data carrier, overcoming the inconvenience of having to change the CD when the driver crosses a national border. A further advantage is that the navigation system calculates the route much more swiftly than on CD-based systems. This is particularly noticeable during map loading and when using the zoom function. This allows a flowing zooming in and out and enables the map to be moved in all four directions. In addition, many more special navigation destinations can be stored on a DVD; these make it easy to find your destination swiftly even if you do not happen to know the name of the road. Destinations and route options are entered in the conventional way via a menu in the MMI. As an alternative, the navigation system can also be operated using voice control. The map and the visual description of the route appear on the large MMI display, whereas the corresponding directions can be read off as pictograms in the Driver Information System's display. The map display corresponds to a normal road map: as well as the name of the road the A8 is currently driving along, it also shows the names of the roads and towns in the vicinity. Advanced key access and authorisation system Drivers of the new A8 now only need to reach for their car key from time to time: "advanced key" is the name of an optional system that acts as an electronic access and authorisation system. The key - which can remain in the driver's pocket - incorporates an electronic pulse generator whose signal is registered and checked by a proximity sensor in the door. If the signal is accepted, the doors are unlocked as soon as the driver operates the button on the door handle. The central locking can be activated and deactivated at any door of the vehicle. All the driver has to do is carry the key on his or her person within a range of about 1.5 metres from the car and to actuate the door handle. The passenger can also be the first to open the door. It is possible to select via MMI whether the central locking should only release the manually actuated doors or unlock all of them. The advanced key system also means that the steering is released and the ignition turned on electronically and wirelessly before the start of a journey. Provided the driver has the key on his or her person while inside the car, the steering is released by pressing the starter button. At the same time the ignition is activated and the electronic immobiliser released. Then the engine can be started at the starter switch on the centre console. For safety reasons, the selector lever must be in the position "P" or "N" and the driver must actuate the foot brake. The engine can of course also be started in the conventional way by turning the key in the ignition lock. When leaving a vehicle equipped with advanced key, it merely suffices to press a small button on the outside handle on the driver's door in order to lock all doors. Once again there is a dialogue between the key and the in-vehicle sensor: it is therefore impossible to lock the doors accidentally. This system is not only convenient, it also benefits security. The mechanical ignition lock previously used has been replaced by an electronic version. The key identification process with advanced key is fully electronic and consequently enables they key to be clearly assigned to the right vehicle.
Driver-oriented personalisation: one-touch memory It is not uncommon for luxury-class vehicles to be used as business cars, by a succession of different drivers. Audi is unveiling a new comfort and convenience aspect for this target group on the new A8: a wide range of functions and settings can be matched up to a specific driver and activated automatically once they have been automatically identified. The new system which goes by the name of "one-touch memory" simply uses the driver's fingerprint on the starter button of the advanced key authorisation system to identify who is driving the car. The sensor pad, which is only the size of a postage stamp, consists of 65,000 electrodes that scan in the fingerprint. The system produces a digitised grey-scale image based on the differences in distance between the skin and sensor surface. In just fractions of a second the system then assesses the quality of the image and decides whether it is sufficient to identify the driver. Once the system has positively matched the fingerprint recorded with stored prints, an array of processes are initiated: the seats, mirrors and steering column are adjusted in line with the pre-selected configuration, as are the air conditioning system's temperature and air distribution settings. One-touch memory can also activate infotainment settings such as the radio volume, preferred radio station and tone settings. Up to four different people can benefit from the convenience of the system, and store their preferences via MMI inputs. The system also provides a personal address book for each user, with space for up to 100 entries. Thanks to one-touch memory, the driver is saved the trouble of having to learn the kind of PIN codes that are designed to make keyless personalisation possible elsewhere. At the same time, fingerprint-assisted identification makes it impossible for drivers to be confused with each other and therefore allows the use of individual settings if car keys are swapped over, for example. Radar-assisted distance control: adaptive cruise control An intelligent "travelling companion" is available as an option on the new Audi A8: adaptive cruise control, a radar-assisted distance control system. This system builds on the functionalities of the standard cruise control system and appreciably enhances driving convenience by automatically regulating the vehicle's speed to maintain a specified distance from the vehicle in front. This noticeably reduces the driver's workload particularly during long journeys on country roads or when driving in heavy nose-to-tail traffic on the motorway. The system's sensor is accommodated out of sight behind the trim grille on the cooling air inlet. While the car is on the move, it emits radar signals that determine how far ahead the next vehicle is. A computer then establishes whether that distance is increasing or decreasing based on the change compared with the previous measurement, and adjusts the car's own speed correspondingly by manipulating the accelerator or the brakes. The Audi development engineers have deliberately limited the intensity of possible acceleration and that of brake intervention and very definitely designed the distance control as a convenience system. Adaptive cruise control is designed so that when approaching another vehicle that is travelling at a completely different speed, the driver himself has to react consciously and in accordance with the situation in hand. Adaptive cruise control can be called up via a steering column stalk, with four different programs available: In the ultra-dynamic program Distance 1, tiptronic may automatically shift down one or two gears if necessary, to accelerate the car swiftly. The Distance 2 and Distance 3 programs are particularly suitable for moving along smoothly with the flow of traffic on busy roads. Distance 4, on the other hand, is for keeping a considerable distance from the vehicle in front and for gentle acceleration - ideal for relaxed driving on fast country roads. The driver can select the basic adaptive cruise control configuration at the MMI, where he decides which program is to be called up automatically each time the system is activated after starting the engine. When equipped with adaptive cruise control, the A8's driving area has a large five-inch central display in the instrument cluster, displaying the selected program by means of symbols. A warning symbol, supported by an acoustic signal, is in addition flashed up here if the distance from the vehicle in front is becoming critical and the driver actively needs to apply the brakes. The speed range used by the system is between 30 and 200 km/h. |
| Terms of Use | Copyright © 1996-2008 by AudiWorld. All rights reserved. |
