As humankind continues to boldly venture into space, modern technology is being tested under the most extreme of environments. On top of that, we are relentlessly pushing the limits of lightweight and cost-effectiveness of the objects we launch into space.
Together with our partner, Aerosint, Josefine Lissner and her team tapped into the power of Algorithmic Engineering to create compliant bi-metallic thermal actuators that check the boxes for aerospace applications.
How might multi-metallic structures be useful within industrial settings?
Multi-metallic printing enables us to use different metals to their strengths within single-piece structures, unlocking possibilities that impact many facets of engineering.
For instance, optimizing between performance and cost-effectiveness currently requires us to think about designs and make trade-offs between materials, but we can eliminate this process by combining different metals through multi-metallic printing. Let’s say we are creating a structure that needs to be strong only at certain points, we could designate those areas to be printed in stronger materials such as steel, and assign a cheaper alternative to the rest of the structure.
We can also channel the flow of thermal energy or electrical currents by routing more conductive metals within lesser conductive ones, which is very useful for advanced space hardware such as satellites.
This also leads us to metallic compliant mechanisms, that deforms in a controlled manner to achieve desired mechanical motions. Our thermal actuators are examples of compliant mechanisms that make use of thermal expansion of different materials to create mechanical displacement.
The idea of using thermal expansion of different metals to achieve controlled mechanical displacement is nothing new. Bimetallic strips have been used since as early as the mid 18th century and are still being used today for temperature monitoring and sensing. However, they suffer from a limited range of motions as compared to conformal mechanisms.
Multi-metallic conformal mechanisms like the ones we have created are not only lightweight, but also perform more complex motions such as radial expansion or clamping motion. This makes them very attractive for many industrial applications.
How does Algorithmic Engineering help in the creation of compliant mechanisms?
With Hyperganic Core, our software platform for Algorithmic Engineering, we are able to algorithmically frame the engineering challenge while taking into consideration the properties and constraints associated with materials and printing technologies.
Our collection of A.I.-based engineering tools then rapidly generates variations of objects based on physical rules that achieve target motions, be it expansion, twisting, clamping or more.
As we are reaching beyond the creative confines of the human brain with computer algorithms, the objects and structure generated by Hyperganic Core are more complex, intricate and design-tailored towards a suitable deformation behaviour. We can then methodically study these behaviours of the variants to understand what works and what does not.
A key advantage of Algorithmic Engineering and Hyperganic Core becomes more apparent as the technology of printing gradients between metals become viable. That is where transition areas between the materials are no longer abrupt and are blended in a gradual gradient.
While the creation of such gradient areas is unfeasible with surface-based geometry representations, we can accomplish this effortlessly thanks to Hyperganic’s proprietary voxel-based geometric kernel. It is akin to drawing points in space with different colors — where there is a point of color representing material A, the printer prints a point of material A, and the same goes for the other materials.
How does Algorithmic Engineering redefine your role as an engineer?
Although many of us, myself included, are aerospace engineers by training, we have a lot of knowledge that is beneficial for other vastly different fields of engineering. The same is true for other disciplines.
Algorithmic Engineering enables me to encode such knowledge into computer code to generate parts, structures and entire machines that I may never be able to manually model in Computer-Aided Design software fast enough, or even at all.
Albeit the “encoding” of our knowledge may take a little bit of time, we only need to do it once and that knowledge can now scale immediately to tackle ten other challenges at the same time.
No longer am I spending time drawing designs manually. I can work on a more abstract level and thinking of solving challenges more generically, where the algorithms I write can be applied to other specific cases too. If I venture into another challenge next time, I can then piece together the other blocks of algorithms required to build a solution for it. The potential for such an algorithm-driven approach to design is immense and I look forward to a day where every engineer can reap the rewards of this new paradigm.
Josefine Lissner graduated with a Masters in Aerospace, Aeronautical and Astronautical/Space Engineering from the University of Stuttgart in Germany. As part of the Mercedes-AMG Petronas engineering team she contributed to the aerodynamic design of the Formula 1 race car that won the world championships in 2018.
Her work at Hyperganic focuses on next-generation hardware for spaceflight, advanced automotive applications, bio printing and other strategic areas.