Designing Safer Inflatable Space Habitats
An important technology for the future of long term space missions is the use of expandable, inflatable space habitats.Â Inflatable habitats are key to reducing the weight of space structures, and are not constrained by the size of the launch vehicle.Â In order to ensure the reliability of these structures, Luna is working with NASA and the Embry-Riddle Aeronautical University to research and develop a structural health monitoring (SHM) system that can detect and locate damage in an inflatable habitat structure.
The flexible materials used in these inflatable structures, including Kevlar woven straps, have been shown to exhibit creep and other forms of degradation over time. Additionally, space structures are subject to impact from high-velocity micrometeoroids and other bits of space debris.Â A comprehensive and reliable system is needed to monitor the integrity of the entire inflatable structure.Â Researchers from Embry-Riddle Aeronautical University have developed a type of carbon nanotube based â€˜buckypaperâ€™ incorporating a layer of piezoresistive strain sensors to cover the outer structure. This will be combined with Lunaâ€™s high-definition fiber optic sensing (HD-FOS) integrated into the interior layer of the structure.Â Luna sensors were bonded directly to the flexible Kevlar straps that are woven into the structure.
The first phase of research has demonstrated that the HD-FOS and its ability to monitor surface strain with a resolution of 0.65 mm is very effective for detecting small changes in the state of the structure. HD-FOS, combined with the carbon nanotube sensing material, shows great promise in providing full coverage health monitoring and precise impact detection and assessment.Â Luna continues to work with NASA and ERAU to refine the approach and move the system closer to reality.Â You can read an overview of the project here, or a summary of the first phase of research here.