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Additive manufacturing has enabled the production of lattice structures with tailored mechanical properties. However, process limitations still exist, affecting the quality of the struts, practically limiting sizes and types of printable unit cells. Typically, long, thin, unsupported horizontal struts exhibit large deviations from ideal geometries, due to high surface roughness and internal porosity. AlSi10Mg specimens were designed and fabricated by laser powder bed fusion to investigate the role of strut orientation, size, and overhang length using different sets of process parameters. Visual inspection, three-dimensional scanning, and metallographic inspection of the cross-sections were performed. A quality control methodology based on dimensional and geometric tolerances has been defined in order to quantitatively characterize the quality of the struts. Optimized process parameters were selected and used to fabricate octet-truss specimens which were then characterized by compression testing.

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Venus and the Ocean Worlds are emerging areas of interest for space exploration, as they can potentially host, or have hosted, conditions compatible with life. Landers and probes for in-situ exploration, however, must deal with very high external pressure, due to the environmental conditions, often resulting in thick and heavy structures. Robust, reinforced shell structures can provide a lightweight solution for the primary structure. In this frame, the isogrid layout is already a standard in aerospace, especially for flat panels or cylindrical shells. In this paper, isogrid-stiffened hemispherical shells, or “geodesic domes”, are described, focusing on the case of a concept of a Venus lander. Early design methods for both plain and geodesic domes subjected to external pressure are presented, providing design equations. Additive Manufacturing is identified as the key technology for fabricating metallic geodesic domes, due to the complexity of the internal features. Moreover, it allows to fabricate ports and integrated thermostructural systems in the same process, potentially resulting in improved performance or cost and schedule savings.