NASA's Extravehicular Mobility Unit, or EMU, is a personal mini-spacecraft that comprises the space suit assembly and life support systems. The current EMU has a manually operated extravehicular visor assembly (EVVA) that provides protection from micrometeoroids and from solar ultraviolet and infrared radiation. For the integration of EVVA with NASA’s next generation space suits helmet bubble, dynamically switching technologies are needed to provide tint-ability, radiation protection, and optimized transmittance. Giner proposes to develop an electrochromic space suit helmet bubble that would provide high optical contrast between its clear (transparent) and dark (opaque) states, tunable switching, and a control module that would allow for both user and ambient light control. This electrochromic visor will provide >55% contrast at 550 nm, rapid (~ 1 sec) switching, and low power requirements. Taking advantage of flexible transparent electrodes, a new generation of solution processable electrochromic polymers, and robotic coating on doubly-curved surfaces, Giner will develop and thoroughly test a prototype visor that meets or exceeds the performance and durability requirements listed by NASA. At the end of the program, a full size (10” 13” hemi-ellipsoid dome), self-powered prototype visor will be delivered.
The main application for our electrochromic visor is NASA’s next generation Z-2 spacesuit. Our helmet bubble would allow instant darkening when exposed to sunlight or by user input to protect the astronaut’s eyes from solar glare. In addition, our device could provide tunable change in transparency (variable shading) on windows used in space stations and vehicles, or on deep space shelters.
The ability to tune the color of helmets would be useful for military personnel such as aircraft pilots. There is also a broad range of civilian applications for our electrochromic polymer in its laminate form including building windows, automotive glass, commercial aerospace, eye wear and helmet visors.