Fullscreen HTML5Med Res (??MB)HTML4

The Most Complex Car . . . . packed full of electronics in a way never before seen DaimlerChrysler has recently released its “Maybach” luxury sedans – amongst the most expensive cars ever built and certainly the most complex. T he cars are simply jammed with electronics – there is barely a function or component that isn’t either electronic or controlled electronically. In fact, there are no less than 76 electronic control units in the car! Let’s have a quick look at some of the highlights. To suggest that the rear compartment is luxurious is something of an understatement. Seated behind a glass partition that can vary in transparency via a sandwiched liquid crystal membrane (a glass sunroof uses the same technology), passengers can electrically adjust the fore-aft movement and backrest angle, with the latter able to be reclined to 47°. A memory facility allows these settings to be recalled. In addition, the seats contain a pneumatic lumbar massage function, whereby an internal bag is alternately filled and relieved of air. If the buyer requests, the rear seats can also be equipped with active ventilation: eight fans can be adjusted in three stages to waft air through the seat perforations. Not including the optional fans, each rear seat contains seven electric motors, complete with their own electronic control unit. Part of the programming of the system involved ensuring that the occupant’s body was always fully supported while movement was taking place. 4  Silicon Chip Between the rear seats is the entertainment console. This includes a DVD player, radio (includes VHF reception), TV tuner, 6-disc CD changer, two telephone systems, a refrigerator compartment with its own electric compressor – oh yes, and a system that holds in place a champagne bottle and fine sterling silver goblets (they’re not electronic but we just thought you’d like to know about them!). The centre rear console also contains controls for the www.siliconchip.com.au . . in theWorld central locking, the TELEAID system through which help can be gained in an emergency (more on this below), intercom system and sockets for connecting a camcorder, MP3 player or video games. Home theatre in the car In the rear of each front seat is mounted a 9.5-inch TFT flat screen. Displayed on the screens can be the TV program (PAL, SECAM and NTSC can all be received), the output of the DVD player or various car system controls. As passengers are watching the movie, they can enjoy the Dolby digital surround sound effects through the Bose sound system. The system has a total audio output of 600 watts and uses no less than 21 speakers. A sound processor is equipped with an interior microphone to detect any changes within the cabin (eg, a variation in the number of occupants) and it adjusts the output to suit. The driver and front passenger are provided with a centrally-mounted 6.5-inch colour TFT screen. SMS, WAP and email can all be accessed with this display. However, DVD and TV reception is not available on the front screen once the vehicle’s speed www.siliconchip.com.au by Julian Edgar exceeds 8km/h. The front screen also displays the navigation system output. The DVD-based system includes the entire European road network, in addition to information on the locations of petrol stations, railway stations, airports, hotels and restaurants. A dynamic route guidance facility takes into account information received via the Traffic Message Channel of the Radio Data System. This traffic message system is available in Germany and the Netherlands. Climate control air-conditioning The climate control system of the car uses two complete systems. In addition to temperature, it also automatically takes into account the intensity of the sunshine, pollutant levels in the outside atmosphere and the humidity. The systems use two infinitely adjustable refrigerant compressors and in conditions where there is an external temperature of 48°C and a solar insolation of 1kW per square metre, they are said to be able to drop the interior temperature from 70°C to 25°C “within minutes”. Each of the four occupants is able to adjust their own air temperature and air flow. These personal settings are stored in the memory of November 2002  5 the appropriate electronic ignition key – presumably for when the car is being used with many different chauffeur/ occupant combinations. The rear passengers have no less than ten air outlets. With the exception of the footwells, the airflow through each outlet can be individually controlled via means of a control wheel operating electric motor-actuated flaps inside the vents. Some of the systems being controlled include:  The Parktronic system, where ultrasonic sensors on the front and rear bumpers are used to measure the distances to the nearest objects. The driver is informed of this via a display and acoustic signals.  Distronic – proximity-based cruise control system that uses a radar sensor located behind the front bumper and maintains a constant gap to the car in front. The system can apply the brakes in addition to modulating the throttle.  Linguatronic (no, I didn’t make the name up!) is a voice control system that can be used to operate the audio, communication and navigation systems. In fact, only the sound volume cannot be changed by voice command – one assumes because if it gets too loud it may not be able to hear shouted commands to quieten down!  An electronic Keyless-Go system automatically unlocks the doors and bootlid as the driver approaches the car. The electronic ignition key receives signals from induction aerials located in the doors, in the centre console, beneath the parcel shelf and in the rear bumper. The key then sends out an identification code; if this code corresponds to the value stored in the memory, the driver can enter the vehicle immediately or open the boot lid. Pressing a button on the shift lever of the automatic transmission then starts the engine. Passenger protection Should the vehicle be involved in a crash, the TELEAID system automatically calls for help through the car’s fixed-installation phone. In addition to informing emergency services of the accident, the system also guides the services to the scene. The system can be triggered by either the airbag sensor or the roll-over sensor. In addition, vehicle occupants are able to send an SOS at any time by pressing either of the two cabin-mounted red SOS buttons. TELEAID is currently operational in Germany, the USA and Japan. The airbags are of a two-stage design. These take However, these motors are actually under the control of the climate control electronics, making it possible to vary the distribution of air without affecting the volume of air flowing into the cabin – which can be as great as 715 cubic metres/hour. In total, the climate control system uses 14 electric motors. Also available (as an option) is a roof-mounted 63-watt solar panel which circulates air through the interior of the car when the ignition is switched off. Driving the monster The 76 electronic control units in the car communicate via four CAN databus networks and an optical databus. 6  Silicon Chip www.siliconchip.com.au Powerful headlights, LED tail lights into account the mass of the individual seat occupants and the severity of the crash impact to inflate the bags either partially or completely. In addition to driver and passenger airbags, there are four side airbags (each integrated into a seat backrest) and four window bags which deploy curtain-like across the side windows. As well as inflating in a side impact, the window bags are triggered during a rollover. Of course, a car like this would never break down but should the unthinkable happen, help can be gained through the Telediagnosis service. By pressing a button on the car phone, communication is established with a central Customer Assistance Centre. A customer adviser is then able to speak to the driver while at the same time viewing data transmitted from the car – vehicle and engine model, year of manufacture, engine temperature, battery voltage, mileage and any fault or warning messages stored in the memory. The vehicle location is also transmitted. Telediagnosis is currently available in Germany and the USA. Shortly before the next service is due, the car automatically contacts – via its phone – the Customer Assistance Centre, and transmits details of the vehicle’s condition and any necessary maintenance work that is required. Personnel at the centre then arrange for this work to be completed at the service. Gas discharge headlights are fitted to the Maybach. Unusually, the gas-discharge lights are used on both high and low beams, with a shutter sliding between the lamp and the lens to obscure the upper part of the beam when low-beam is being used. On high beam the shutter is retracted and additional halogen spotlights in the inner headlights are switched on. With the exception of the reversing lights, the tail-lights are fully LED – a total of 528 LEDs is used. The high-mount centre brake light and the side indicator repeaters in the exterior mirror housings also use LEDs. The complete lighting system is managed by an electronic control unit that has various emergency lighting functions stored in its memory. Should a data link or electronic control unit fail, the automatic emergency program comes into operation, preventing failure of the complete lighting system. And if a bulb fails, other lights are automatically switched on to compensate. Power to burn The non-electronic technologies of the Maybach are just as advanced – from the automatic height-controlled air suspension, glass that contains an intermediate layer of four plastic membranes to reduce noise transmittance, to the 405kW twin turbocharged 5.5-litre V12 engine, which can accelerate the 2.7-tonne Maybach to 100km/h in an astonishing 5.2 seconds. Whether you see the Maybach as an obscene example of an excess of wealth being used to squander the earth’s resources or alternatively, as one of the most admirable cars ever built, rather depends on your viewpoint. But you can be certain that many of the electronic technologies seen in the Maybach will trickle down to cars that you and I are likely to be driving in the future. SC www.siliconchip.com.au November 2002  7