Carbon Core of next-gen BMW 7 Series helps reduce sedan’s weight by up to 130 kg; remote control parking
BMW presented an initial selection of technology highlights for the next generation of the BMW 7 Series model range featuring developments in lightweight design, driving dynamics, comfort, intelligent connectivity and operation.
Due to the BMW EfficientLightweight strategy, the new BMW 7 Series line-up will weigh up to 130 kilograms (287 lbs) less than the outgoing generation of models. At its heart is a body structure with a Carbon Core based on the transfer of technology from the development of the BMW i models. The use of CFRP for structural elements of the passenger cell based on hybrid construction with ultra-high-strength steels—such as the B-pillars—increases both the overall strength and the torsional and bending stiffness of the passenger cell. To this end, the configuration of sheet metal elements can be adjusted as required, allowing for a significant reduction in the weight of the body.
|PreDrive BMW 7 Series camouflaged. Click to enlarge.|
|BMW 7 Series body-in-white / carbon. Click to enlarge.|
|Carbon cores. Click to enlarge.|
|Hybrid construction. Click to enlarge.|
The new BMW 7 Series is the first car to use industrially manufactured CFRP in its body construction not as a visible material in the outer skin, but in combination with steel, aluminum and plastic. It is also the first car in which the CFRP has been fully integrated into the production process, largely based on a globally unique paint application process. Its Carbon Core is thus also an indicator of how significantly the CFRP technology developed for BMW i models can contribute to the minimization of a car’s weight as well as its material strength and stiffness.
The intelligent material mix encapsulated by the BMW EfficientLightweight strategy includes the carefully calculated use of aluminum and ultra-high-strength steels in the body and chassis. This is complemented by the introduction of innovative, weight-minimizing bonding technologies and at-source heat- and sound-proofing for the engine, which allow reductions in the overall quantity and therefore the weight of the insulation materials required.
As well as the development of ultra-lightweight concepts and an intelligent material mix, the BMW EfficientLightweight approach also drives a systematic process of detail optimization for all components with the aim of achieving the best possible result for each class of car.
For the new BMW 7 Series this has meant combining the model’s driving dynamics with comfort. To this end, the engineers have explored innovative new directions in areas such as weight distribution, unsprung masses and acoustic concepts.
Unsprung masses have been reduced by as much as 15% over the predecessor models through a focus on lightweight design for the suspension, brakes and wheels. The implementation of an at-source insulation concept and the use of superabsorbers have led to excellent interior acoustics coupled with a reduction in weight.
The resulting integrated lightweight design concept also enables the car’s center of gravity to be lowered still further and weight to be distributed between the two axles at a near-perfect 50:50 ratio.
In-line 6. Among the power units available for the new BMW 7 Series will be a six-cylinder in-line variant from the BMW Group’s latest engine generation. The crankcase, cylinder head and oil sump of the new drive unit are made from aluminum. The TwinScroll turbocharger uses an indirect intercooler integrated into the intake manifold and teams up with High Precision Injection, the latest version of VALVETRONIC fully variable valve control and Double-VANOS variable camshaft control for the intake and exhaust valves. As well as its enhanced efficiency, the new generation of the straight six also offers even more rapid responses.
Integral Active Steering and Dynamic Drive. A further development of the Integral Active Steering system can be specified as an option for the new generation of the BMW 7 Series. The planetary gear set at the front axle used previously has been replaced by a variable rack and pinion ratio. This allows Integral Active Steering to be offered for the first time in conjunction with the BMW xDrive intelligent all-wheel-drive system.
By steering the rear wheels either with or in the opposite direction to the front wheels (as the situation demands), this system increases both maneuverability in urban environments and agility. It also guarantees extremely comfortable and assured reactions when changing lanes and through corners.
There is also the option of the further developed Dynamic Drive active roll stabilization system. This technology employs, for the first time, electromechanically driven stabilizers to reduce roll during dynamic cornering.
Air suspension and Dynamic Damper Control as standard. The standard-fitted two-axle air suspension with automatic self-leveling noticeably enhances the ride comfort of the next-generation BMW 7 Series. The springs are supplied with air by an electrically driven compressor with pressure accumulator. The height of the car body above the road is therefore adjusted to the load on board even when the engine is switched off.
Regulating the supply of air for each wheel individually allows an unevenly loaded car to be balanced out. An additional function is manual activation of the self-levelling function. At the touch of a button, the height of the body above the road can be raised by 20 millimetres—e.g. on uneven surfaces or in multistory car parks with sharply-angled ramps. At speeds over 35 km/h (22 mph), the self-levelling function automatically restores the default setting. Moreover, at high speeds and when SPORT mode is activated using the Driving Experience Control switch, the body is automatically lowered by 10 millimetres.
The benefits of air suspension at the front and rear axle are felt particularly keenly when the system teams up with the likewise standard Dynamic Damper Control. The electronic dampers further improve the sedan’s primary and secondary ride, as well as its dynamic properties. The Driving Experience Control switch can be used to select from three damper control settings enhancing ride comfort (COMFORT and COMFORT+ modes) and sporty, agile handling (SPORT mode) respectively.
Further developed Integral Active Steering and Dynamic Drive. A further development of the Integral Active Steering system can be specified as an option for the new generation of the BMW 7 Series. The planetary gear set at the front axle used previously has been replaced by a variable rack and pinion ratio. This allows Integral Active Steering to be offered for the first time in conjunction with the BMW xDrive intelligent all-wheel-drive system.
By steering the rear wheels either with or in the opposite direction to the front wheels (as the situation demands), this system increases both maneuverability in urban environments and agility when dynamic progress is the order of the day. It also guarantees extremely comfortable and assured reactions when changing lanes and through corners.
There is also the option of the further developed Dynamic Drive active roll stabilization system. This innovative technology employs, for the first time, electromechanically driven stabilizers to reduce roll during dynamic cornering.
Driving Experience Control switch now with ADAPTIVE mode. The next-generation BMW 7 Series now also allows the driver to activate ADAPTIVE mode using the standard-fitted Driving Experience Control switch.
In this setting, the car set-up adapts with clearly noticeable responses to driving style and route characteristics. The system reacts to movements of the accelerator and steering wheel and to the position of the selector level (in D or S). According to the situation, either the sporty or the comfort-oriented characteristics of the powertrain and chassis systems are brought to the fore. In cars equipped with the optional Navigation system Professional, map data is also used to ensure the right set-up is selected when moving from city streets to motorway, for example, and when negotiating twisty roads or approaching a junction.
The Driving Experience Control switch positioned on the center console has been given a new design. COMFORT, SPORT, ECO PRO and ADAPTIVE modes can now be selected directly by using buttons. The COMFORT button is also used to select the COMFORT+ mode should an even more cosseting ride be required. SPORT and ECO PRO modes allow drivers to configure the set-up as they desire via the iDrive menu. For example, in SPORT mode drivers can combine dynamic shift characteristics and direct steering responses with a comfort-oriented damper setting. In ECO PRO mode the range of efficiency-enhancing settings can be adjusted to individual preferences. Dynamic functions—i.e. the damper control tuning and steering responses—can now also be configured separately for ECO PRO mode.
BMW gesture control. The iDrive system in the new BMW 7 Series—which, for the first time, uses a Touch display—also hosts the debut appearance of BMW gesture control. Pre-defined hand movements near the center console—registered by a 3D sensor—provide an extremely intuitive and user-friendly way of operating frequently used infotainment system functions. Gestures can be used to adjust the volume of audio programmes, for example, and to accept or reject incoming telephone calls. Users can determine the function to be activated by another pre-defined gesture—e.g. navigation instructions to a home address or screen deactivation—as they wish.
BMW gesture control can be used as an alternative to conventional operating methods without having to activate it separately. A symbol on the Control Display indicates whether gesture control may be used, depending on the situation.
Remote control parking. The new BMW 7 Series is the world’s first series-produced car that owners will be able to maneuver in or out of parking spaces or garages without anyone at the wheel. As such, the remote control parking option allows access to extremely tight parking spaces. (Earlier post.)
Using the likewise newly developed BMW Display Key, the driver can prompt the car to enter or exit a parking space fully automatically. To activate the remote control parking function, the car has to be positioned at a maximum angle of 10° to the selected parking space. The maximum distance that can be covered by the car during driverless maneuvers in and out of parking spaces is 1.5 times the length of the car.
Even drivers behind the steering wheel will receive more assistance than ever when parking. The latest version of the optional Parking Assistant makes it easier to select and use parking spaces positioned parallel or transversely to the road. The system takes over the entire parking process, including all the steering, gear changes, acceleration and braking maneuvers required. In addition, the system also includes the Active Park Distance Control function. During reversing maneuvers, it uses precisely timed braking inputs to help avoid collisions with obstacles around the rear or sides of the car.
Driving assistant. Rear collision prevention and cross- traffic warning for the area around the rear of the car have been added to the functions of the optional Driving Assistant system. For both functions the data supplied by radar sensors mounted on the sides of the rear end is analysed.
In order to reduce the risk of a rear-end impact, high-frequency hazard warning lights alert vehicles following behind, as required. If a collision can no longer be avoided, the Active Protection system’s protective measures, such as belt tensioning and closing of the side windows and sunroof, are activated automatically. The cross-traffic warning system helps the driver when reversing out of a parking space in situations where visibility is restricted. Audible alerts and an LED light in the exterior mirror warn the driver of cross traffic. If the optional rear view camera is specified, an extended image of the traffic situation behind the car appears on the Control Display.
As well as the Active Cruise Control system with Stop & Go function and cross-traffic warning system (front), the Driving Assistant Plus system also includes the steering and directional control assistant with Traffic Jam Assistant and the Lane Departure Warning Assistant with active side collision protection. These systems use a stereo camera and radar sensors at the front and sides of the car to detect road boundaries, vehicles travelling ahead and those approaching from the side or rear.
At speeds up to 210 km/h (130 mph) they use smooth steering inputs to help drivers stay in the center of the lane or avoid unintentional departures out of their lane. When changing lanes, the systems can also help avoid collisions with vehicles on either side of the car or approaching from behind. Additions have also been made to the functionality of the Active Cruise Control system with Stop & Go function. Once in use, the touch of a button will now suffice to acknowledge speed restrictions detected by the Speed Limit Info function and adapt the selected speed accordingly.