Die Extravehicular Mobility Unit (EMU, englisch für Mobile Aussenbordeinheit) is an independent anthropomorphic system that provides environmental protection, mobility, life support, and communications for a Shuttle or ISS crew member to perform Extra-vehicular Activity (EVA) in Orbit. It is currently one of two space suits used by crew members on the ISS, the other being the Russian Orlan-Raumanzug.
Suit Components
BearbeitenThe EMU, a result, like the A7L spacesuit, of years of research and development, consists of a Hard Upper Torso (HUT) assembly, a Lebenserhaltungssystem (PLSS) which incorporates the life support and electrical systems, arms, gloves, EVA helmet assembly, and a soft "lower torso unit" (LTU), incorporating the waist seal, legs, and boots. Prior to donning the suit, the astronaut puts on a urine containment device (UCD), over which a special union suit, called the "Liquid Cooling and Ventilation Garment" (LCVG), that incorporates clear plastic tubing for body temperature control (via chilled liquid water) and ventilation tubes for waste gas removal, is worn.
Once the astronaut dons the LCVG, the astronaut then puts on the LTU, similar in nature to a firefighter putting on the pants and boots of his or her fire protection suit on Earth. The astronaut then floats into the airlock where the LCVG umbilical is connected to the umbilical in the HUT, after which the two parts of the suit are locked together using the waist seal. Once the suit is turned on and checked out, the astronaut then dons a "Snoopy cap," a brown fabric communications cap dating back to the Apollo days that incorporates a pair of earphones and microphones, allowing the EVA astronaut to communicate with both the crew members in the Orbiter and ground controllers in Houston. After donning the "Snoopy cap," the gloves and helmet are then locked on, pressurizing the suit. The suit's regulator and fans activate when the servicing umbilicals are removed and the suit reaches an internal pressure of 4.3 psi. A typical EMU can support an astronaut for 8 1/2 hours, with 30 minutes of reserves in the case of primary life support failure.