Rapid Prototyping at Zero Gravity for In-Flight Repairs and Fabrication on Space Station Freedom

The ability to perform in-flight rapid prototyping would be of great benefit to NASA in two ways. First, repair parts could be fabricated from CAD designs beamed up from earth based laboratories which might allow a failed experiment to proceed. The mission specialists themselves, under the creative influence of space flight, might design a new part or tool and fabricate it on board in a matter of hours. Second, with metal casting and ceramic sintering facilities on board, rapid prototyping would allow manufacturing in space. This paper presents some test criteria for evaluating two of the rapid prototyping techniques, stereolithography and fused deposition, in microgravity conditions. Effects of the variation of head speed and strip width for the fused deposition process on the resulting mechanical properties are presented. The mechanical strength of the polyamide test bars increased with both increasing head speed and strip width. Increasing head speed would be desirable in microgravity applications.Mechanical Engineerin