Development of Advanced Environmental Protection Garments Containing Shear Thickening Fluid Enhanced Textiles (STF-ArmorTM) for Puncture Protection and Dust Mitigation

摘要

Environmental protection garments (EPG) containing shear thickening fluid (STF) enhanced textiles can provide multi-functional protection and bridge key EVA suit technology gaps to enable sustainable human exploration missions beyond low Earth orbit. Work completed under a Small Business Technology Transfer Research (STTR) Phase I award and NASA EPSCoR awards at the University of Delaware demonstrated prototype STF-enhanced EPGs that address key technology gaps related to physical hazard protection (i.e. dust mitigation, secondary ejecta/MMOD, puncture) for future crewed exploration missions, including lunar and planetary exploration. STF-textiles have superior flexibility, and thus, have a significant competitive advantage over other puncture-resistant materials, and are amenable to the construction of advanced suits that combine a high level of crewmember protection with high mobility. This paper describes the development and ongoing testing of STF-enhanced EPGs, including physical, thermal, and environmental testing of new STF-enhanced textiles and lay-ups. STF formulations meeting vacuum stability/offgassing requirements were successfully developed and applied to the Orthofabric shell layer and to candidate absorber layer textiles. STF-enhanced EPG layers were shown to have two to three times higher standard puncture force with only 10-30% mass add-on and no change in flexibility as compared to the untreated textiles. New test methods for evaluating the penetration of regolith through EPG layers are presented. The combination of STF and superhydrophobic “lotus leaf” coatings was shown to prevent dust infiltration into the shell fabric and facilitate removal of surface dust. Prototype STF-containing EPG layups developed in the Phase I STTR are scheduled to be flown to the ISS on the Materials on the International Space Station Experiment (MISSE-9) in 2018.