K. Hsu
Arizona State University,
United States
Keywords: solid-state, metal additive manufacturing, metal joining, ISAM, in-space manufacturing
Summary:
Driven by the need over the past decades of increasing world-wide access and utilization of the Low and Geostationary Earth Orbits for commercial, civil, and military and intelligence applications, key advancements in various area of ISAM have been in development to support of a range of In-Space Operations (ISO). While development and adoption of new capabilities in all areas of ISAM are interconnected, the ability to manufacture-or transform raw or recycled materials into components, products, or infrastructure-in the Space environment lies at the core of ISAM. Through these successful efforts, additive manufacturing or 3D printing demonstrated its overall potential to serve as the core technology on which In-Space manufacturing capabilities can be built. However, critical capability gaps also became clear in not only the ability to inspect and qualify printed part, but also a suitable metal 3D printing technologies capable of working in the space environment supporting radiation and/or micrometeoroid shielding, applications where thermal stability and material off-gassing issues are critical. Fundamentally, a new end-to-end autonomous metal 3D printing and inspection operation based on a metal shaping and joining technique that does NOT rely on thermal melt-fusion or powder feedstock can bring In-Space manufacturing of metallics components and structures into reality. This type of approach can enable various modality of metal part fabrication, surface repair, and joining of dissimilar materials in the Space environment where and when it is needed. The Resonance Assisted Deposition (RAD) technology, demonstrated by the author’s team, builds net-shape metal parts using oscillatory-strain energy with solid metal wire feedstock without melting. Its fully mechanically confined material mechanics allows this technique to be unaffected by gravity conditions. This solid-state technology removes all barriers to implementing and deploying metal 3D printing in the Space environment. When fully transitioned and fielded, this approach can enable a future scenario where a range of items are produced and inspected on-orbit or at the point of need in three modalities: discrete small-to-medium component printing, collaborative-robotics enabled large-structure production, and In-Space metal structure joining and repair. The core RAD technology in such this solution is a wire-based solid-state metal shaping and joining technique applied to fabrication of metal parts and repair of metallic surfaces. The process physics of the core technique removes the safety, power consumption, heat management barriers of applying metal 3D printing and joining technologies in the Space environment. The eventual implementation of the core technique through autonomous, collaborative robotics and its integration with in-process, and post-fabrication inspection allows for a solution system to operate in production scenarios for qualifiable, end-use metal components and structures from hand-sized tools to tens-of-meters-scaled structures. This implementation method can significantly advance the current use-case of metal 3D printing on the International Space Station beyond its severely limited utilities.