Design and Manufacturing of FANG (Fabric ANchoring Gadget) for Fabric Repair on the International Space Station

This paper presents the development of the Fabric Anchoring Gadget (FANG), an innovative tool designed to address NASA's Micro-g Neutral Buoyancy Experiment Design Teams (NExT) 2025 Softgoods Attachment Device challenge. On the International Space Station, fabric protects thermal and external equipment. If this fabric is damaged, astronauts may need to perform an Extravehicular Activity (EVA) to repair it by attaching a new piece on top of the existing one. In response to this challenge, the NASA Micro-g NExT Team in the Illinois Space Society at the University of Illinois Urbana-Champaign has designed FANG. FANG enables astronauts to securely attach overlapping pieces of fabric during EVAs while only accessing the outer face of the material. The device features a system of retractable “fangs” that push a sharp conical needle into the fabric to create pilot holes, followed by a handle that pushes a clip into the pre-existing holes and secures the fabric together. This device was designed to be used in microgravity conditions, and the design process involved extensive consideration of EVA challenges and safety, including, but not limited to, restricted mobility and single-sided access to the fabrics to reduce safety risks. To comply with NASA and Neutral Buoyancy Laboratory (NBL) requirements while enhancing usability, FANG includes safety features such as dual-factor caging mechanisms to limit user interaction with potentially sharp or hazardous parts and ergonomic handles to reduce fatigue. The prototyping process of FANG revolved around 3D printing and several rounds of iterative CAD design. Some modifications include resizing FANG’s frame to conserve space and resources, changing the types of grip on the handles for usability, increasing the length of the pushing handle’s shaft, and resizing it for smoother motions. The device then underwent various tests to validate its performance against NASA's Micro-g NExT challenge requirements. Such tests include, but are not limited to, structural fatigue testing of the pins and clips, testing ergonomics of the handles and mechanisms for user fatigue, security of the clips, etc. Preliminary data indicates that FANG can easily puncture the fabric, insert the clips, and the clips hold the fabrics securely. Planned improvements to safety, reusability, and ergonomics such as clip stability, handle grips, and a clip reloading mechanism are currently being designed and implemented. Further testing such as simulating astronaut gloves and varying clip sizes and thicknesses is planned. This paper details the device’s design, manufacturing, prototyping, and iterative testing processes, as well as a comprehensive safety analysis, were conducted to ensure FANG’s alignment with NASA requirements and guidelines for EVA operations. FANG aims to improve the longevity of the International Space Station and fix any damages to softgoods materials by attaching new fabrics.