2002 Maybach 62

On the safe side

Intelligent lightweight construction plays a major part during the development of an automobile as majestic in size as the Maybach. Using the latest calculation methods, innovative design processes and high-quality, lightweight materials the engineers were able to achieve significant results in reducing the weight of the bodyshell without compromising strength, rigidity and vibration comfort. On the contrary, with a static torsion of 1.82 millimetres per metre (between the axles) and a static bending of 0.22 millimetres (at the side members) the new Maybach achieves unequalled results in its vehicle class.
The fact that the bodyshell including all external fittings tips the scales at "only" 622 kilograms , and yet passes the most stringent crash tests with flying colours and offers its occupants the highest level of safety, is due to intelligent body design and the widespread use of high-strength steel alloys. These achieve maximum strength (= safety) with the minimum of material (= weight). The proportion of total bodyshell weight accounted for by these high-strength steels is approx. 41 percent.

Five large aluminium components also contribute to the exemplary, low weight of the Maybach bodyshell: the roof, bonnet, doors and front wings. The boot lid and spare wheel recess are made from high-quality glass-fibre reinforced plastics.

Doors: "superplastically" formed aluminium

The Maybach engineers broke new technical ground when designing the doors, which are made wholly of aluminium. "Large dimensions, low weight" was the criterion which favoured this material. Another important aspect was the structural rigidity of the slim window surrounds, which in turn has a major influence on the aero-acoustics or noise comfort at high speeds. The result of these complex analyses is a masterpiece of modern bodyshell design:

• The window surrounds consist of welded, high-strength multi-chamber extruded sections with outstanding structural rigidity.

• For the first time the complex internal door components and hinge reinforcements have been produced using the technique of "superplastic forming". This involves forming the aluminium components at temperatures of up to 500 degrees Celsius under increasing pressure. Owing to the relatively long time it requires, this innovative process is particularly suitable for exclusive, limited model series such as the Maybach and guarantees the highest precision, quality and crash stability.

• The interior door components and window surrounds are directly laser-welded together.

• The integral side impact protection likewise consists of multi-chamber extruded sections, which exhibit impressive rigidity with a low component width. These are arranged horizontally in the front doors, while the engineers decided in favour of a diagonal arrangement in the rear doors for the greatest possible safety.

In addition to high-tech lightweight construction and a high level of safety the doors of the Maybach 62 have functions which make access and egress more convenient. A newly developed hydraulic system ensures that from an opening angle of 15 degrees the doors are arrested in any position – even on gradients or in strong winds. The pneumatic closing aid pulls all doors of the Maybach (and the boot lid) firmly closed

Crash structure: robust forked members in the front end

When designing the front-end structure the Maybach developers drew on the unique expertise of the Mercedes-Benz brand, using a feature which offers numerous advantages in passenger cars of this size, namely the forked member. These are robust, straight longitudinal members on both sides of the front body structure which fork towards the transmission tunnel and side skirts in front of the firewall to disperse impact forces efficiently during an offset frontal collision. This imposes uniform loads on the tunnel, floor and side wall, thereby reducing any deformation of the passenger cell to a minimum.

The Maybach also features two flexurally rigid cross-members: one at the very front of the front-end structure, where it acts as a tensile structure and activates both side members to absorb energy during an offset frontal collision, and a second transverse structure consisting of two separate cross-members at wheel height in front of the firewall. This prevents any penetration into the footwell in the event of an accident.

The body structure also absorbs crash energy at a second longitudinal member level above the front wheel arches. These robust sheet metal sections of high-strength steel extend from the front end to the A-pillars. The two side members beneath the doors are equipped with special impact-absorbing elements at the front. These brace the front wheels during a crash and thereby protect the integrity of the firewall.

Passenger cell: systematic, all-round protection

The extremely rigid passenger cell is the heart of the body structure, and therefore also of the safety concept. It is designed to provide its occupants with the best possible all-round protection thanks to a sophisticated package of individual measures:

• Beneath the dashboard a tube of high-strength steel bolted to the A-pillars on both sides ensures a high level of transverse rigidity. This is supported by a strut on the transmission tunnel and also provides a firm mounting for the dashboard, the steering jacket tube and various major assemblies.

• In the form of an integral tubular frame, both side walls of the Maybach have a special design feature which considerably improves occupant protection during frontal and side impacts, as well as in the event of a rollover. The high-strength steel tube of 28-millimetre diameter reinforces the A-pillar, the front section of the roof frame and the B-pillar. The multi-part construction of the side wall enables the engineers to adapt the material thickness to the loads encountered in the different impact areas, while welded-in bulkheads in all structural components lend additional stability to the large side walls.

• The understructure consists of a separate central tunnel with a steel sheet thickness of 1.4 millimetres, an additional tunnel reinforcement and floor panels welded to the side members on both sides. In addition four die-cast aluminium cross-members bolted to the tunnel increase the longitudinal and transverse rigidity of the floor. In the event of a side impact three robust cross-members beneath the seats and at the rear of the passenger cell absorb the crash energy.

• During a rear-end collision a robust structure of high-strength steel sections at the rear end of the luxury car provides the passengers with protection. These large box-sections are able to absorb very large forces, and as in the case of the front-end structure a robust cross-member ensures that both longitudinal members help to dissipate the energy. This is particularly important during an offset rear collision. The steel fuel tank is located above the rear axle, i.e. outside the impact area.

Equipped with this sophisticated all-round protection package the new Maybach was subjected to numerous crash tests at the Mercedes Safety Centre, where it passed even the most stringent with flying colours. These included

• ...a frontal 40-percent offset impact against a deformable barrier acc. to the European NCAP procedure (New Car Assessment Programme);

• ... a 100-percent frontal impact against a rigid barrier acc. to US-NCAP;

• ... a lateral 90-degree impact acc. to the Euro-NCAP standard;

• ... the pole impact test acc. to Euro-NCAP and US regulations (FMVSS 201);

• ... the US-NCAP side impact at an angle of 27 degrees.

• …the US rear impact.

Airbags: activation according to accident severity

A highly-effective, adaptive restraint system provides the highest level of occupant protection. Adaptive means that the driver and front passenger airbags automatically adapt to the severity of an accident. Moreover, the electronics register the weight of the front passenger and also take this value into account when activating the front passenger airbag as the situation requires.

Acceleration sensors mounted on the radiator cross-member in the front end – known as up-front sensors – allow the severity of an impact to be recognised at an early stage and thereby create the conditions for adaptive airbag control. Accordingly the front airbags are activated in two stages depending on the accident severity: during a minor frontal impact the electronic control unit activates only one chamber of the two-stage airbag gas generators, and the airbags are inflated to a lower internal pressure. If the system detects a heavy frontal collision, however, it also activates the second-stage chambers in the airbag gas generators approx. 15 milliseconds later; the airbags are then inflated to a higher pressure and provide the vehicle occupants with protection suited to the severity of the accident. The early crash detection made possible by the up-front sensors also shortens the time between the impact and the start of belt tensioner activation, ensuring that the occupants are optimally restrained by the seat belts.

The weight of the front passenger is automatically measured by a special membrane in the seat upholstery. To be precise, it is not the actual bodyweight but the distribution of the pressure on the seat cushion that is measured. This enables the electronics to allocate the front passenger to various different weight classes and influence airbag activation accordingly. This means that in a less severe accident both generator stages would be activated to give the best possible protection to a heavy front passenger. In the case of a lightweight front passenger, however, the second airbag stage would only be activated during a more severe accident.

The front airbags in the Maybach have a volume of 64 litres on the driver’s side and 125 litres on the front passenger side.

Seat belt system: fully integrated into the seat

The three-point seat belts with automatic comfort-fit, high-performance belt tensioners and belt force limiters, the indispensable basic components of a modern occupant protection system, are integrated into the seats of this high-end luxury vehicle. This ensures that the belt is optimally positioned in any seating attitude and can therefore carry out its full protective role. The position of the diagonal seat belt is automatically adjusted to the shoulder height of the driver and front passenger via a guide slot.

As a world first the engineers in Sindelfingen have developed a "crash-responsive" backrest for the innovative reclining seats in the rear of the Maybach 62. In the event of an accident the backrests move back into the upright position, thereby ensuring the best possible occupant rebound protection. This is achieved by deformable torsion bars located between the backrest and the rear bulkhead.

The submarining effect – in which rear seat occupants wearing a seat belt slip beneath the lap belt during an accident – is prevented by a buckle-mounted belt tensioner acting on the lap belt and a precautionary seat adjustment feature: in any seat position – including the reclined position – the rear seat cushions are automatically set at a slight angle so that the occupants are firmly supported during a frontal collision and cannot slide forward beneath the lap belt.

Side impact protection: sidebags for all occupants

With sidebags for each seat and two windowbags on each side as standard, the restraint system in the Maybach also meets the highest expectations in terms of side impact protection:

• The four sidebags (volume: ten litres each) are integrated into the seat backrests. During a crash they instantly interpose themselves between the occupant and the door at chest level, reducing the loads acting on the thorax.

• The four windowbags complement the protective effect of the sidebags; during a side impact they deploy across the side windows like a large curtain within 25 milliseconds, thereby providing the passengers with head protection over a wide area. The volume of each front windowbag is 15 litres, those in the rear having a volume of 20 litres each.

The latest accident research findings have led to the development of a new rollover sensor whose information is used by the airbag control unit to activate the windowbags when a rollover is imminent. The air cushions remain inflated for some time after the crash and can also improve occupant protection in this eventuality.

Aerodynamics: drag coefficient of 0.31

Despite its majestic size the new Maybach 62 also cuts a very fine figure in aerodynamic terms and illustrates the high capabilities of aerodynamic development at DaimlerChrysler even in this vehicle class. Expressed in figures: with a frontal area of 2.62 square metres and a Cd figure of 0.31, the drag area is 0.81 square metres.

Nonetheless the aerodynamic specialists in Sindelfingen only regard their work as successful if they are able to show respectable results in the field of handling safety as well. This is where the coefficients of lift at the front and rear axles are the measure of all things. These are extremely low in the case of the Maybach, and form the aerodynamic basis for exemplary handling stability at high speeds or when braking. The speed-related level control function of the AIRMATIC DC (Dual Control) air suspension system also improves handling safety at high speeds: from 140 km/h the system automatically lowers the suspension by 15 millimetres at both axles.

The Maybach developers have reduced both the drag and lift with a number of detailed measures, for example:

• The aerodynamically optimised shape of the bonnet ensures a low airflow resistance across the windscreen wipers.

• The A-pillars are contoured for particularly low drag. The slight curve of the roof and rear window also has a favourable effect on the airflow characteristics.

• The engine compartment trim directs the airflow to the rear and prevents turbulence in this area.

• The large, smooth area of plastic underfloor panelling allows the slipstream to pass beneath the vehicle body with very little turbulence.

• The discreet spoiler lip integrated into the boot lid reduces lift and provides a clearly defined trailing edge.

Aero-acoustics: the minimisation of noise

As in the areas of lightweight construction, safety and aerodynamics, the engineers developing the bodyshell of the Maybach were also at pains to achieve a level of noise comfort which would do justice to this high-end luxury car. Most of this effort was devoted to the avoidance of wind noise, the reduction of tyre and road noise and sound insulation measures for the interior – and with excellent results.

In order to trace acoustic disturbances at source the specialists spent hundreds of hours in the aero-acoustics tunnel, using special microphones and sensors to identify body features which caused wind noise or vibration. The vanes in the front bumper, the exterior mirrors, the A-pillars and the window and roof surfaces were aero-acoustically optimised by this means. The sophisticated sealing systems in the joints of detachable body components, which effectively reduce wind noise in the gaps even at high speeds, are also a result of painstaking, detailed work in the wind tunnel.

Extensive noise insulation measures on various body components help to prevent any remaining wind noise from penetrating into the interior. These include continuous sealing strips on the doors and additional seals on the front wings and roof pillars.

The Maybach engineers paid particular attention to low-frequency noises resulting from vibration in large-area components. It was aero-acoustic measurements that provided important information for the rigid, low-vibration design of the underfloor panelling and its attachment points, for example. The specialists prevented the thrumming that could affect ride comfort when the sliding sunroof is open by fitting an air deflector with four precisely calculated notches in its profile. These create small areas of turbulence and so avoid irritating noises.

Glass technology: noise insulation with plastic membranes

Sophisticated glass technology also plays a major part in the high level of noise comfort in the Maybach: the side windows are of newly developed, laminated glass containing an intermediate layer of four plastic membranes. One of these membranes (0.76 millimetres) is an acoustic insulator and significantly reduces noise in the interior.

The side windows of the Maybach have an overall thickness of 7.2 millimetres – 2.2 millimetres more than conventional laminated glass. Improved break-in security is a useful side-effect of this sophisticated glass technology, as the laminated glass makes the side windows considerably more difficult to break. The windscreen and rear window likewise incorporate acoustically effective plastic membranes and have a glass thickness of 6.2 millimetres.

Last but not least, the grey-tinted glass in the Maybach makes a major contribution to climatic comfort. It not only filters out UV radiation but also reflects the infra-red light in the sun’s spectrum, which accounts for about 53 percent of the entire energy transmitted by sunlight and plays a major part in heating up the interior. Depending on wavelength, a coating of pure silver and other high-quality metallic oxides reduces infra-red radiation into the interior with an efficiency of up to 80 percent. Compared to glass with a conventional green tint, the overall transmission of energy into the interior through the windscreen is reduced from 60 to approx. 47 percent and through the side windows from 44 to 36 percent, thanks to infra-red reflection.

Panoramic roof: transparency at the touch of a button

The innovative, electro-transparent panoramic roof of the Maybach 62 is a highlight of a very special kind. With its elegant cassette structure of exotic wood it extends across the rear section like a glass dome and offers the rear passengers a unique ability to select an individual lighting atmosphere. The manufacturing process for this high-tech glass system is also absolutely typical of the Maybach: it is hand-crafted.

The optional panoramic roof is divided into two halves: the front section incorporates 30 solar cells over an area of approx. 0.5 square metres which convert sunlight into electrical energy and power the ventilation fan of the front climate control system in the Maybach 62 with an output of up to 63 Watts. This solar power flows as soon as the car is parked, and ensures a continuous circulation of fresh air in the interior.

The rear section of the panoramic roof features a number of technical innovations over an area of approx. 0.75 square metres. This roof section consists of two approx. six-millimetre thick panes of glass with an electrically powered, sliding liner between them. The laminated glass pane on the inside has an intermediate layer in the form of a liquid crystal membrane of conductive polymer plastic. The membrane has a cable connection to a control unit which generates an AC output of 90 Volts. Switching the power on arranges the crystals in the plastic membrane in such a way that the glass becomes transparent and allows daylight into the rear of the Maybach 62 over its entire area. The special feature is that as soon as the AC voltage is switched off, the liquid crystals lose their transparent arrangement and the light is fragmented in all directions. The glass becomes opaque and filters the daylight to produce a pleasant, diffused glow, with only approx. 76 percent reaching the interior. This electrically controlled transparency has its world premiere in the Maybach 62. Thanks to this unique roof technology the rear passengers in this luxury motor car can decide in accordance with their mood or the weather conditions whether to enjoy a bright interior flooded with daylight in which to admire an exclusive, panoramic view of the scenery, or whether to relax beneath a semi-transparent glass dome. For dull weather conditions or longer journeys by night the panoramic roof has yet another highlight for an individual interior lighting effect: an illuminated sliding liner.

Apart from the electro-transparent panoramic roof Maybach customers have numerous other possibilities where roof design is concerned:

• In the Maybach 57 they can choose between a fully panelled roof or a sliding/tilting sunroof. For both versions, a solar module is optionally available.

• In the Maybach 62 they are able to choose between an aluminium roof with or without an integrated solar module, an electrically operated sliding/tilting sunroof in the rear with solar module and a sliding/tilting sunroof without solar module. In both cases an electrically operated, sliding liner is included.

Headlamps: lighting features for an unmistakable identity

Taking a close look at the headlamps of the luxury limousine reveals a good example of the attention to detail lavished on the Maybach by its developers: the lenses of the bi-xenon headlamps bear the double-M emblem of the Maybach craft shop – a subtle reinforcement of product identity which is at the same time reminiscent of the legendary Maybach "Zeppelin" of 1930, whose headlamp lenses bore the company trademark.

Bi-xenon is a synonym for the best and most efficient headlamp technology. The great advantages of this system include outstanding brilliance, long range and particularly uniform illumination of the road surface, an important contribution to active safety. The powerful gas discharge headlamps generate their low and main beam with a xenon bulb: while the entire light output is available at main beam, a shutter slides between the lamp and the lens to obscure part of the beam when switching to low beam. When main beam is selected the halogen spotlights (H7) in the inner headlamps are also switched on.

The headlamp units of the Maybach also accommodate H7 fog lamps with the latest projection technology. The driver is able to switch these on together with the low beam headlights or sidelights to provide exceptionally good illumination of the road margins.

The exterior lighting of the Maybach is also unmistakable by virtue of what are called side markers on the outer positions of the headlamp units and in the exterior mirrors. These additional lights in the headlamp units and LEDs in the mirror housings, which glow discreetly when low beam is switched on, characterise the appearance of the Maybach in the dark and make it unmistakable even at night.

A high-pressure cleaning system ensures that the plastic lenses of the headlamps are efficiently and gently kept clear.

Tail lights: 528 LEDs for four functions

The engineers systematically opted in favour of modern LED technology for most of the rear lighting functions. A total of 528 light-emitting diodes make their presence seen when the brakes are applied, or as indicators, tail lights and fog lamps. Only the reversing light has modern HPS bulbs with an output of 24 Watts.

There are many good reasons for using LED technology. One of the most important is the very small space required by light-emitting diodes. It has therefore been possible to distribute the LEDs for the tail lights evenly over the entire surface of the rear light cluster to achieve uniform illumination well into the side areas, whatever angle the lights are seen from. Accordingly the light from each tail light extends from the flanks of the bodywork almost to the middle of the rear end, and represents another lighting feature by which the Maybach may be recognised.

The third braking light on the parcel shelf and the side indicator repeaters in the exterior mirror housings are likewise equipped with LEDs. The mirror housings also incorporate courtesy lights, which are switched on when the door is opened and illuminate the entry area.

Lighting functions: automatic emergency and back-up lights

The lighting system of the Maybach is managed by an electronic control unit whose microchip also has various emergency lighting functions stored in its memory. Should a data link or electronic control unit develop a fault, for example, the automatic emergency function prevents failure of the entire vehicle lighting system. Likewise, if one or more bulbs important for vehicle safety should fail, other bulbs are switched on as a back-up.

Daytime driving lights, which also improve active safety by day in the opinion of accident researchers, can be programmed by the driver using the multifunction steering wheel and the central display in the instrument cluster. The low beam headlamps, sidelights, tail lights and licence plate illumination switch on automatically when the engine is started. If the light switch is in the "Auto" position a light sensor on the windscreen ensures that the vehicle lights switch on automatically in the dark. This Headlamp Assist function also relieves the driver of effort when entering a garage and in rainy or snowy conditions.

A world apart

Effortless power