Multi-Input Strength Loss Sensing for Webbing Structures

Webbing textiles are critical to many personnel safety systems in U.S. Navy aircraft, however there are presently no viable non-destructive techniques to detect when the load strength has degraded to an unsafe level. Luna is developing a multi-input approach to address this need by combining the advantages of mechanochromic dyes/polymers with embedded fiber optic sensors. Mechanochromic dyes will irreversibly record the high-watermark of strain experienced by a webbing under high levels of elongation. Secondary dyes will quantify ultraviolet light exposure and degradation. Distributed fiber optic sensors provide high-resolution, highly-sensitive measurements that detect and localize damage without affecting the integrity of the strap. Combining these technologies enables accurate assessment of the load capabilities for nylon, polyester, and Kevlar structures during their service life. During Phase I Luna will team with New York University to demonstrate the feasibility of this innovative combination of sensing technologies. During Phase II the team will apply the sensing technology to full-scale webbings and evaluate its ability to detect strength loss due to UV exposure, heat/humidity, impact cycling, fluid contaminants, salt fog, blowing sand, and stack gas exposure. During Phase III the technology will be transitioned to the field for acceptance testing.