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Development of a Compliant Mechanism Based on Additive Manufacturing

Programme Reference
Prime Contractor
RUAG Space Germany GmbH
Start Date
End Date
Development of a Compliant Mechanism Based on Additive Manufacturing
Development of a topologically optimized Compliant Mechanism, taking into account opportunities and limitations of the powder-based Additive Manufacturing process for metallic materials. The development shall aim at an optimized flexibility in the compliant degree(s) of freedom and an improved stiffness in the constraint degree(s) of freedom. Furthermore, complexity and weight of the device shall be reduced.
Compliant mechanisms (e.g. flexural joints) are applied where the relative motion of parts can be accomplished without using traditional bearings. Slender structures can be properly arranged to provide functions like accurate guiding, speed reduction, or change of motion direction. Compared to traditional mechanisms using bearings, significant improvements are expected. These include a decrease of part count number, frictionless motion transmission, which decreases losses, higher motion ranges, enhanced stiffness, and improved accuracy due to the avoidance of backlash.
The complex monolithic shapes require highly sophisticated manufacturing methods. Traditional techniques like Electro-Discharge-Machining or machining are hardly applicable. Additive Manufacturing provides exactly these requirements and is seen as a key enabling technology for space. The achievable geometrical complexity is unrivalled today. Furthermore, the technique was matured rapidly over the past years, allowing the manufacturing of fully dense parts with mechanical properties comparable to wrought materials.
The activity will consist of the following tasks:
  • Review of the compliant mechanism design, identifying potential areas which benefit from a re-design for AM.
  • Optimisation of the selected joints in the compliant mechanism using FEM and CAD methods, taking into account the opportunities and restrictions of Additive Manufacturing.
  • Development and optimisation of the Additive Manufacturing process for miniaturised flexural joints and verification of the obtained properties by dedicated test campaign at samples level.
  • Manufacturing and post processing of the optimized components.
  • Testing of the produced hardware.
  • Life time capability assessment, as well as assessment of the impact on cost, mass, lead time, efficiency.
  • Application Domain
    Generic Technologies
    Technology Domain
    15 - Mechanisms
    Competence Domain
    2-Structures, Mechanisms, Materials, Thermal
    38-Advanced Manufacturing
    Initial TRL
    TRL 3
    Target TRL
    TRL 5
    Achieved TRL
    TRL 5
    Public Document