Lightweight Construction Summit 2019 Lightweight Design at Mercedes-AMG: "More Than Omitting Things"
As a performance brand, Mercedes-AMG pursues an integrated lightweight strategy. Uwe Renz, Head of Body Development, presented this strategy at this year's Lightweight Construction Summit - and called for a paradigm shift in development.
For many people, lightweight design and racing cars go hand in hand. However, lightweight design is not only paramount in the performance sector, says Uwe Renz, head of body development at Mercedes-AMG. At this year's Lightweight Construction Summit organized by "Automobil Industrie", he even declared that lightweight construction was currently experiencing a renaissance: Future technology such as electromobility or hybridization would not be possible without it.
“It is unthinkable for us to develop a car that has no focus on lightweight design," continues Renz. The demands placed on the vehicles from Affalterbach are constantly increasing, whether in terms of fatigue strength, rigidity or because of international crash requirements. This is not the end of the list of challenges; pollutant emissions have to be reduced and new driving cycles realized. Despite all this, it is also important not to forget the weight of the vehicle. The performance brand naturally has a lightweight design strategy - the GT-R is suitable for it is a prime example of successful lightweight design. He explained the details of this strategy to the specialist audience in Würzburg.
If you believe Renz, then the body consists of an "optimal mix of lightweight materials". Aluminum, carbon or magnesium were used at the right places. Intelligent lightweight design ensuring dynamic driving behavior is a top priority. But to limit lightweight construction only to the body would not make optimal use of this technology. Rather, the weight of each individual component had to be reduced: For example, the substructure strut of the GT-R is made of carbon fiber-reinforced plastic (CFRP) and is topologically optimized; the connecting areas were also improved.
All of this measures serve the purpose of achieving high rigidity, as the vehicle must ultimately be transversely dynamic. Once again, Affalterbach was able to reduce the weight of a drive element by 40 % compared to the previous one, also by using CFRP. Lightweight design involves the optimization of the details of each component," says Renz, before a part can be approved, engineers and designers must check whether it could be made even lighter. Basically, it is important to always achieve the optimum combination of cost, weight and function.
Lightweight Design at Mercedes-AMG: The Strategy Counts
The performance brand benefits from its Stuttgart-based parent company, especially in the field of classic lightweight material construction. The cooperation with Daimler is close, he says, and there is a great deal of know-how in the Group, especially in dealing with carbon. The second pillar of the lightweight design strategy is conceptual lightweight design. Essentially this means: Only the combination of the right material and a specific concept results in a well-balanced and optimized component. With regard to the overall vehicle concept, the topics of load path optimization and load path optimized design are essential.
Uwe Renz therefore calls on his professional colleagues to be embrace a paradigm change: "Our sector needs to adopt even more new approaches. At Mercedes-AMG this means: From CAE to CAD". In other words: consider as early as possible the load of the components and optimize the topology to achieve a balanced design in the end. And even then, it is important for designers to consider whether it is possible to reduce material thicknesses or omit a connection point. However, this detailed optimization requires the corresponding mindset on part of the employees. "For car manufacturers, lightweight design is not simply 'de-contenting', i.e. not simply omitting things," says Renz. And lightweight design is much more than just weight management.
Another basis of the sports car manufacturer from Affalterbach is specified lightweight design. This involves in-depth know-how about details in lightweight design. Keyword know-how: Renz thinks it is a pity that only a few universities offer lightweight as an explicit content in their courses: "Lightweight design is the core of our development work," says the engineer. Similarly, development service providers, OEMs or automotive suppliers should adopt a lightweight design strategy.
Lightweight Construction as a Key Technology
In order to integrate lightweight design as a key technology in tomorrow's mobility concepts, we need adequate framework conditions. These conditions were the subject of a keynote speech by Thomas Fuhrmann-Bäcker from the Federal Ministry of Transport and Digital Infrastructure. The Federal Government expressly supports lightweight construction: Fuhrmann-Bäcker wants a wider industrial application and cross-industry cooperation. New materials and manufacturing processes have made better results possible - and they are needed for future technologies.
This article was first published by Automobil Industrie.
Original: Svenja Gelowicz / Translation: Alexander Stark