Description of the component:
The Max Planck Institute for Extraterrestrial Physics and the University Observatory Munich asked APWORKS for an innovative and particularly lightweight mirror mount and its production using additive manufacturing.
The MPE and the USM develop astronomical instruments that are installed on the world's largest telescopes. Such instruments contain various optics such as folding mirrors, which have mirror mounts that are currently produced using conventional manufacturing methods.
APWORKS GmbH,
APWORKS GmbH,
APWORKS GmbH,
Challenges:
Astronomical instruments often contain very complex optics and have high weight restrictions, which leads to complex geometries for the mechanical parts. At the same time, they place high demands on mechanical precision as well as on the rigidity and strength of the materials used. All of this makes astronomy an ideal field of application for additive manufacturing.
As space and weight are crucial for these astronomical instruments, the mirror mount required design optimization and an innovative manufacturing method that supports the optimized design with all its design freedom.
Due to the advantage of design freedom, additive manufacturing was chosen as the preferred production method. The choice of material brought further advantages, as Scalmalloy®, a highly innovative aluminum alloy, combines the low weight of aluminum with almost the specific strength of titanium. The material has already proven its exceptional mechanical properties for years in aerospace and motorsport applications and was recently approved by the FIA and included in Formula 1 regulations.
Solution:
The objective in designing and manufacturing a new mirror mount was to save weight through an innovative design and to produce a new component that could be mounted on the existing structure of the observatory.
APWORKS engineers designed an optimized mirror mount based on topology optimization. They defined areas where the software can optimize structures and those that must be completely retained in order to mount the bracket to the existing mirror structure. An algorithm only provides material where it is needed to withstand all applied loads. The design suggested by the algorithm was reworked by APWORKS engineers for the component. It is bionically inspired and can be produced using additive manufacturing.
The optimized component design of the mirror mount was printed from the high-strength aluminum alloy Scalmalloy® and saves 82% of the original volume. It is manufactured to meet the highest tolerance requirements so that it can be mounted on the existing structure of the observatory. Compared to the conventional part design, the 3D printed mirror mount combines five parts in only two parts, which significantly shortens the production route due to a reduced number of assembly, manufacturing and quality control steps.
Conclusion:
The additively manufactured mirror mount for the Wendelstein meteorological observatory withstands the same loads as the conventional design, saves 82 percent volume and thus reduces the weight of the component to the same extent. This result was made possible by optimizing the design and using the high-strength aluminium alloy Scalmalloy®.