3i-PRINT individualize - integrate - innovate

1. Idee. 9 Monate. 6 Parter. Das Ergebnis: Geballte Kompetenz.

The idea

“…metal additive manufacturing in body-in-white design already works today. We wanted to make 3D-printing graspable.”

Tweet: #3iPRINT: individualize – integrate – innovate

In the background of 3i-PRINT we find the body-in-white competence of csi entwicklungstechnik GmbH, virtual product development and additive manufacturing.

On the example of a complex, crash relevant vehicle front structure of a VW CADDY I youngtimer we show the potential and added value of industrial metal 3D-printing for the automotive industry.

Project goal is giving impulses and outlooks into the future of car body construction and making them graspable with your own hand. Against the background of the electrification of the automobile, e.g. regarding drive technology and actuators, thermal management, package and weight reduction are key points for the engineering and design of the concept. Future topics are flexibility, customizability, functional integration and sustainable lightweight design.

“We are proud of the achieved total weight of the complete frame concept of only 34 kg.”

The result

“…through time pressure the team had only one try at most of the tasks – that was a team-challenge overarching different companies. Design concept, 3D-printing, welds and the vehicle restoration have to be perfect.”

The result of our collective work is the world’s first, all-metal additively manufactured, functionally integrated vehicle front structure on a scale of 1 to 1 using the latest technical standards.

During the 3i-PRINT project our functionally integrated vehicle front concept has been imagined, simulated, designed and manufactured, with use of additively manufactured high strength and fracture-tough Scalmalloy® aluminum alloy. In parallel the Team Concept Workshop of csi entwicklungstechnik GmbH lovingly restored a Volkswagen CADDY I youngtimer.

3i-PRINT is an agile engineering-platform for research and development for rapid implementation of ideas together with our partners. On this platform prototype concepts can be timely presented. 3i-PRINT is an open platform for collaboration, where we also like to materialize your ideas.

Scalmalloy® is a material development of AIRBUS APWORKS GmbH together with the experts of AIRBUS. You can find further information regarding the material here:

- Scalmalloy® material data sheet
- Scalmalloy® overview

“…Scalmalloy® has a specific strength almost of titanium and is at the same time fracture-tough and corrosion-resistant.”

The vehicle front structure concept has been completely designed in the virtual world by csi entwicklungstechnik GmbH with Altair tools in a productive concept and series development environment. Real world load cases of the automobile industry have been used (stiffness, strength) and the structure has been designed for fulfilment of the current requirements regarding crash and vehicle safety. For the design of thermal management functions CFD-simulations have been conducted.

For reaching a virtual data base of the vehicle, the whole body-in-white of the youngtimer vehicle was 3D-scanned. This has been an additional challenge for the designers of csi entwicklungstechnik GmbH compared to common series developments, as the 3D-scanned surfaces are not described parametrically and mathematically, but the surfaces are made from a number of triangular surfaces. Thus a smart tolerance concept had to be found for the assembly of the frame. After manufacturing and post processing the frame was measured. All required tolerances could be followed and there were no considerable thermal distortions.

The achieved final structural total weight of 34 kg (measured before assembly at vehicle) is presentable. During the design phase the manufacturability and assembly process have continuously been coordinated between csi entwicklungstechnik, APWORKS and GERG.

The method

At the core of the vehicle front structure concept is the use of the advantages of Additive Manufacturing:

Free material selection, flexibility, without tools
Functional integration
Media storage
Thermal management
Load path and crash optimized topology
Creative freedom

Free material selection, flexibility, without tools:
when using Additive Manufacturing methods the concept, design and procurement of costly and complex tooling does not apply. The components can be completely rethought. Specifically regarding small series and niche applications 3D-printing already today has advantages, if we calculate with a holistic approach. At the same time the material choice and with it the flexibility is high: no matter if you like to manufacture your structure from Aluminum as we did (e.g. Scalmalloy®), or steel or even titanium. The powder-bed-method and the machines of EOS allow this and much more.

Functional integration:
we believe that 3D-printing makes sense, if we integrate as many functions as possible into a printed component. The printing time of the component is the same, no matter if the part is of a simple or complex shape. If we just replace cast parts, as is often the case with 3D-printing today, then we will not be able to use the full potential of additive manufacturing. Completely new designs require design engineers with experience in 3D-printing and a cooperative view on the overall system. For this reason we integrated various functions into our vehicle front structure concept as an impulse. A side effect is the optimization of the available package space, as package space is also close calculated in electric vehicles.

Media storage:
in our concept we integrated the wiping water tank into the area of the strut tower. In the same way coolant or refrigerant of the air conditioning system can be stored inside the load carrying structure. In the distant future we can even think about storing liquid and gaseous fuels in the structure. For making this happen we need further research and development together with our automobile OEM customers.

Thermal management:
if the load carrying structure takes a part of the necessary cooling by heat dissipation through integrated cooling channels and cooling ribs, then necessary coolers or even laser-lights can be scaled down. In the end this will save weight, energy and therefore saves the environment. Goals for the thermal management are e.g. the cooling of battery packs in electric vehicles or the brakes.

Load path and crash optimized topology:
the valuable material is only supposed to be in the places of the structure, where it is necessary for the fulfillment of mechanical or customer requirements. For this reason the organic design of our concept has been development purely in the virtual world with help of Altair tools like HyperWorks, Evolve and Inspire. For short vehicle front structures our concept can improve crash behavior through use of multiple load paths and the usage of the inside of the component.

Creative freedom:
with additive manufacturing you can completely individualize structures. What about having YOUR own car in the future? Due to additive manufacturing designers can realize attractive designs, which are impossible to manufacture with classical production processes. The possibilities reach e.g. from shell structures and hollow structures up to lattice structures.

Long-term future perspective multi-material-printing and integration of electrical circuits, circuit boards and sensors: today this is research and dreams of the future. Our vehicle front structure concept shows as an impulse, in which direction technology will move. Load sensors for Structural Health Monitoring and component integrated chips will open up new possibilities for lightweight design and energy savings.

Crash optimization:
our novel and optimized crash-management-system has high specific energy absorption, as it is almost completely free of manufacturing constraints and can be adjusted to the specific vehicle requirements. That means with the same function it weighs less than comparable conventionally manufactured systems.

Simplification of the joining and assembly process:
with additive manufacturing the part number can be reduced drastically. Thus our concept can be mounted as a complete module to the vehicle body. Through reduction of the amount of joints at the same time the local dynamic stiffness increases, which benefits driving comfort, acoustic behavior and vehicle dynamics.

The perfect, fast and uncomplicated interaction of partner companies is becoming more and more important. This makes it possible to go from an idea to results, which move forward the state of the technology, within only 9 months.

From idea to hardware

csi entwicklungstechnik GmbH initiated 3i-PRINT and signed responsible for methodical idea generation, project management, concept, simulation, design as well as the vehicle preparation.

 

csi entwicklungstechnik GmbH started with their signature methodical idea generation. In this connection the team elaborated design drafts on the basis of hand sketches. The focus was always the added value for the user at the end of the process chain.

Subsequently the structure has been designed completely virtually inside the Team Simulation of csi entwicklungstechnik GmbH.

In connection to this the Team Body-in-White of csi entwicklungstechnik GmbH designed and finished the optimization loops of the vehicle front structure in a specifically established process suitable for Additive Manufacturing.

Altair delivered the HyperWorks-Suite as well as SolidThinking Evolve and Inspire. With their help the concept layout was created and optimized in the virtual world. csi entwicklungstechnik has integrated these tools into their typical productive concept and series development environment, where the tools integrated seamlessly.

AIRBUS APWORKS GmbH printed the single components of the functionally integrated concept. Critical here is the expertise and experience at the parameter selection for 3D-printing. For every single component and the complete vehicle front structure there was only one try in the short available time.

The single parts of the concept have been manufactured on a system EOS M 400 for industrial 3D-printing. EOS contributed their manufacturing-systems- and process-know-how and made sure, that the print jobs were performing in a stable and reliable way. In the result an excellent and pore-free part quality could be assured.

 

Heraeus supported with the material expert knowledge and metal powder, which is necessary to manufacture such a concept without thermal warping and in highest quality.

Modell- und Formenbau Blasius Gerg contributed the frame assembly and post processing out of the single components. For the successful installation of the front frame concept in our youngtimer vehicle the assembly had to satisfy smallest manufacturing tolerances.

During the whole process all participants were sure:
There is no second try!

If we were able to inspire you, we also gladly materialize your ideas. Just get in touch with us!