There was a time when Mercedes-Benz, referring to new model development would mention the word “decade.” Now, development schedules are down to less than a third of a decade, and according to Prof. Dr. Thomas Weber, that figure is slated to reduce even further.
Weber, Member of the Board of Management of Daimler AG, Group Research and Mercedes-Benz Cars’ Development, said: “We will continue to shorten our development time—by three to five months is potentially possible. Until now, the final design and the technical features of a new model had to be determined 35 months before market launch. In the future, we will set these details considerably later and will, therefore, be much more market orientated.”
The use of digital prototypes in the early phase of new Mercedes’ model development is particularly significant, being responsible for having reduced project development by about a year. “And less hardware at the beginning of the development process saves both time and money,” he said.
A significant contribution to this has been Mercedes’ platform strategy.
“We build our vehicles mainly on two basic vehicle architectures, for front- and rear-wheel drive, and with around 100 standardized modules," said Weber. "Using a larger number of shared components, we are able to develop and produce our new model series much more efficiently than their predecessors to achieve bigger economies of scale and standardization of assembly processes.”
Another salient aspect of Mercedes/Daimler’s enhanced R&D and production efficiency concerns joint ventures and what is termed “co-operations” around the world. Weber describes these as being important in terms of market-specific characteristics and research themes, as local “know-how” can be applied
“First, there is our co-operation with Renault/Nissan—at the moment certainly one of the most important partnerships," he said. "Together with them, we are working on many projects, not only regarding the smart car successor but also on topics like small, fuel-efficient engines and transmissions.”
As with many OEMs, China is a major Mercedes market. The company is working with BYD Auto to develop an electric vehicle for the Chinese market and in the U.S. with Tesla Motors on electric projects.
The fuel-cell saga
For those who may be losing patience with the long drawn-out gestation of fuel-cell development to series production levels, Weber has a positive message; he is emphatic in his support of the technology. Fuel cells continue to be a relatively mainstream technology for Mercedes, and the company is working with Ford and Nissan in the area.
“Together, we want to send a clear signal to suppliers, politicians, and the industry to continue building a worldwide hydrogen infrastructure," he explained. "At the same time, pooling our experience in development and production brings competitive advantages and cuts the cost of investment. This enables us to launch the first competitive fuel-cell vehicles in 2017.”
While all this strategic development work keeps Weber and his teams busy, he says that one of the biggest challenges being faced today is to meet growing demands in individualization. “Different customer wishes in different markets lead inevitably to an increasing diversity of variants. The challenge is to meet the customer’s wishes on the one hand and to reduce complexity and costs on the other.”
It is not easy, but he said: “The answer to this challenge is our consistent platform strategy. It allows us to create an extraordinarily broad product spectrum.”
An overarching aspect of what the customer wants—and global legislation demands—concerns sustainability, with its emphasis on husbanding all resources, while creating ecologically and economically viable products. Weber says Mercedes/Daimler will further intensify its efforts.
“We are convinced that emissions regulations can give a clear guideline for the development of green technologies," Weber said. "But the directives should not only be defined on the basis of political discussion; they must also consider the technical feasibility. However, I think new vehicle technology alone cannot deliver the results society desires.”
'Actors and factors'
An ongoing concern for automakers is that for market success, new technologies must be affordable for end-users. “Therefore, policies must take an integrated approach involving all relevant ‘actors and factors.’ Ambitious CO2 targets and the market success of electric mobility can become a reality if forces are joined. The infrastructure for hydrogen and electric power must be matured; consumers and customers must have an incentive to buy and use the available solutions; and energy sources must be renewable.”
Weber is convinced that the future “definitely” lays in the electrification of the vehicle—but not exclusively. “Our road to the future has three lanes: we rely on innovative combustion engines, an intelligent mix of hybrid drives, and zero emissions electric vehicles driven by battery or fuel cells.”
IC (internal combustion) engine developments include diesels with very high injection pressures—above 2000 bar (29.0 psi). Weber believes that for diesel engines, a moderate downsizing with less complex aftertreatment might be more cost-effective than greater downsizing with complex aftertreatment. “In addition, I expect modern aftertreatment systems to become the more cost competitive the higher the overall production volume grows.”
Weber has no doubts that the “attractiveness” of the diesel will remain.
Complementing these areas are established aspects of technology such as aerodynamics. Mercedes has two climatic wind tunnels, and this year will see the commissioning of a new aero acoustic tunnel.
With its compact CLA sedan achieving a best Cd of only 0.22 (previously detailed by AEI at http://www.sae.org/mags/aei/11931), Mercedes has demonstrated what can be achieved.
“If you want to get a Cd well below that, it gives rise to conflicting goals, not only with design but also with important vehicle characteristics—narrowing of the rear end for example," Weber warned. "Although it has definite advantages in terms of Cd, this reduces the interior and trunk width. Consequently, seating comfort as well as load capacity and usability are limited. And a narrower rear track has drawbacks for driving dynamics and design.”
Aerodynamics plays a part in Mercedes’ 3-D Body Engineering philosophy for weight reduction (an improvement of 0.01 in Cd means two grams of CO2 less in mean fuel consumption, says Weber) but, of course, so too do materials. Mercedes’ aim is to reduce the body weight of all its future vehicles by about 10% compared with predecessor models, stated Weber. To help achieve this, Mercedes applies the maxim, “the right material in the right place.”
Advanced materials
Advanced steels combine extreme strength with very good ductility. “However, they are as yet hardly available on an industrial scale, so for the bodies of our forthcoming Mercedes-Benz vehicles, aluminum will be even more interesting," said Weber. "Special casting processes permit more complex geometries in components compared with sheet steel. I am sure that if high-performance aluminum alloys reach the production stage and costs are further reduced, a variety of added applications for the material might ensue.”
Carbon fiber is used by Mercedes—around 30 ton (27 t) a year goes into its products—but as always with the material it is cost that is the challenge. However, fiber composites, including carbon, with their greater potential for reducing mass, are an important element of the company’s mass-cutting programs. Lightweight design is considered by Mercedes from a multidimensional aspect, the 3-D body engineering philosophy bunching together all measures to save weight.
With the year 2020 now just a full model generation away, when asked which new technologies would he like to see incorporated into those models, Weber’s immediate response was that technologies—such as those based on sensors—now develop very quickly. “So in a decade, many things will be possible in the automobile that today seem to be in the realms of science fiction. I think that in 2020 we will see vehicles that are intelligently networked—comprehensively—in all areas. They will be permanently connected to the Cloud, enabling the customer to gain access to all required information at any time.”
The intelligent network would be with other vehicles or the traffic infrastructure via car-to-car and car-to-X communication. “This makes it possible, for example, through demand-actuated control, to maintain traffic flows and so provide for more efficient, environment-friendlier traffic.
“I can fully imagine that in 2020 we will surely also see further partially or fully autonomous driving functions in automobiles—on condition that the legal framework changes accordingly. And I can certainly imagine that in 2020 we will offer our customers driving-assistance systems for motorways that relieve them of part of the work of driving—whenever it is more annoying than fun!”