With its F 700 research car, Mercedes-Benz redefines the idea of effortless, superior refinement: this concept for a future luxurious touring sedan shows how outstanding riding quality can be combined with high levels of environmental friendliness, and good performance with exceptionally low fuel consumption. Thus, the 5.17 meter (204 in) long F 700 with its innovative and very spacious interior design enables an entirely new and exceedingly comfortable mode of travel. The F 700 is the world’s first car that can anticipatively recognize the condition of the road and level out the uneven spots with its active PRE-SCAN suspension, further improving suspension comfort substantially. The forward-pointing DIESOTTO drive system introduced in the F 700, a four-cylinder with a displacement of only 1.8 liters, combines the strong points of the low-emission gasoline engine with the consumption benefits of the diesel drive. Its CO2 emissions of a mere 127 grams per kilometer correspond to consumption of only 5.3 l/100 km (44.38 mpg/US, 18.86 km/l) of gasoline, extremely low for a vehicle of this class.
The new Mercedes-Benz research car: The definition of relaxed refinement
In the words of Professor Dr. Herbert Kohler, responsible for Group Research & Advanced Engineering Vehicle and Powertrain at DaimlerChrysler AG, “With the F 700, Mercedes-Benz shows what the big touring sedan of the future will look like. It offers environmentally compatible mobility combined with utmost comfort and an effortlessly superior drive.”
With that, the F 700 meets the growing demands on luxury-class automobiles. The focus is on conserving resources and protecting the environment: low consumption, low CO2 emissions, low pollution levels. For in future there will continue to be considerable demand for the comfortable mobility provided by large sedans.
Making this kind of mobility sustainable is a major responsibility which Mercedes-Benz faces up to in an all-out way. The F 700 is an unmistakable sign of this: as a research car it demonstrates with innovative approaches and technologies not only how resources can be conserved and the environment protected, but also how driver and passengers can be relieved of stress and can travel completely at ease.
“Sustainable mobility only can be realized by intensive research and development. Technological progress is decisive for creating suitable products for an increasingly more critical world,” says Professor Dr. Herbert Kohler.
The F 700 research car shows new ways to achieve resource-conserving mobility. The heart of the car is the novel drive system which combines the advantages of the low-emission spark-ignition engine with the consumption advantages of the diesel drive.
The diesel engine’s crucial advances to its current combination of dynamic performance and low fuel consumption were made possible by turbocharging and common-rail direct injection – both pioneering achievements of Mercedes-Benz. The “DIESOTTO” drive takes this some decisive steps further: consistent downsizing through reduction of displacement and the number of cylinders makes for improved efficiency, and a hybrid module assists the internal combustion engine mainly in stop-and-go operation. Moreover, the diesel principle with controlled auto ignition (CAI) makes its debut in the spark-ignition engine.
On starting and at full load, the air-fuel mixture is ignited by a sparkplug as in a conventional gasoline engine. The controlled auto ignition (homogeneous combustion) to which the DIESOTTO automatically reverts within its working cycle occurs under partial load conditions, i.e. at low and medium engine speeds.
As a result of homogeneous combustion at reduced reaction temperatures, very low emissions of nitrogen oxides are produced. The rest of the emission control work in the DIESOTTO drive is handled by a standard three-way catalytic converter. In addition, in order to combine the individual subsystems into one drive concept, a highly efficient engine management and control system has been implemented.
The drive unit of the F 700 is a compact four-cylinder with a displacement of 1.8 liters, and yet it ensures that feeling of effortless, superior power afforded by a luxury sedan: a two-stage turbocharger system ensures good response and torquey pulling power. In addition, when the car moves off the internal combustion engine is assisted by the electric motor of the hybrid module. The maximum output is 175 kW (238 hp), the electric motor pitches in another 15 kW (20 hp), and the system’s maximum torque is about 400 Nm (295 lb-ft). The 0 to 100 km/h (62 mph) sprint time of 7.5 seconds attests to the dynamics of the F 700, whose top speed is limited to 200 km/h (124 mph). Despite these outstanding performance figures, the consumption of the F 700 in the standard cycle is only about 5.3 l/100 km (44.38 mpg/US, 18.86 km/l), equivalent to CO2 emissions of 127 grams per kilometer – extremely low for an automobile of this category.
Similar advances are made by the F 700 in the area of ride comfort. Mercedes-Benz has always been a leader in the area of road roar/tire vibration characteristics and suspension comfort: the Active Body Control suspension system in the CL-Class, S- and SL-Class sets the standard worldwide with its unrivaled combination of comfort, handling safety and dynamics. This system is now surpassed by the new technology of the F 700.
For here, once again, the new research car takes an important step to the future: thanks to its active PRE-SCAN suspension, the vehicle not only responds with great sensitivity to roadway unevenness; more than that, it acts with foresight.
PRE-SCAN uses two laser sensors in the front headlamp units as “eyes.” They deliver a precise image of the condition of the roadway. Based on the image supplied by the laser sensors and the information on the vehicle state, the control unit figures out a specific strategy which the high-pressure hydraulics translate into precisely calculated fluid flows and pressures for each single wheel.
The exceptional efficiency of the overall concept of the F 700 is evident at first sight: its design is distinguished by soft, flowing forms. “Aqua Dynamic” is the name the designers have given to this design idiom with which they translated the flow dynamics of a fish into the design of an exceptional automobile. Besides, the design provides an immediately indication that much room has been given to the passengers. With an overall exterior length of 5.18 meters (204 in) the F 700 is a little shorter than the current long-wheelbase version of the S-Class, but with its generously sized wheelbase of 3.45 meters (135.82 in) the research car excels the production model by impressive 28.5 centimeters (11.22 in).
The side view of the F 700 is marked by the tense curves of the roof contour and shoulder line. This sedan puts a new interpretation on a design theme of Mercedes-Benz, for the current CLS also displays such tense lateral lines. The distinctively shaped front wheel arches likewise are inspired by a current model – the S‑Class. After all, even a research car is always a Mercedes-Benz and stands on the foundation of the automobile brand with the richest tradition in the world.
The headlamps of the F 700 are a futuristic interpretation of the Mercedes-typical twin-headlamp face. Two vertical rows of linear LED arrays with superposed lens have the function of driving lights. A third vertical row of single high-performance LEDs are the daytime driving lights. Together with the continuous contour lights they give the F 700 an unmistakable appearance even by night. The “eyes” of the F 700 are integrated into the headlamps: these laser scanners gather the roadway data for the active PRE-SCAN suspension. Unlike any conventional automobile this sedan “sees” the surface profile of the road ahead of it.
The driver’s door also “observes” its surroundings attentively. In the base of the mirror of this PRE-SCAN door there is a very compact laser scanner which examines the area in which the door swings open for any obstacles. If collisions threaten, the door is arrested by a controllable hydraulic cylinder.