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In July 2001, during Space Shuttle Flight 7A, the Joint Airlock was added to the International Space Station (ISS) and utilized in performing the first extravehicular activity (EVA) from the ISS. Unlike previous airlock designs built by the United States or Russia, the Joint Airlock provides the ISS with the unique capability for performing EVAs utilizing either U.S. or Russian spacesuits. This EVA capability is made possible by the use of U.S.- and Russian- manufactured hardware items referred to as Servicing and Performance Checkout Equipment (SPCE) located in both the Joint Airlock's Equipment and Crew Locks. This paper provides a description for each SPCE item along with a summary of the requirements and capabilities provided in support of EVA events from the ISS Joint Airlock.

At the NASA/Johnson Space Center, an electronic version of the wrist-mounted paper checklist currently utilized by crewmembers performing an extravehicular activity (EVA) from the Space Shuttle Orbiter has been developed and evaluated aboard Shuttle flights STS-64 in September 1994, STS-63 in February 1995, STS-69 in August 1995, and STS-72 in January 1996 as a EVA flight experiment. The anticipated benefits of the electronic checklist include improved astronaut EVA productivity by providing a portable, on-orbit programmable, self-contained information display system allowing the EVA crewmember to have ready access to a much larger database than is currently provided by the spacesuit's paper checklist.

International Space Station includes a Joint Airlock in the U. S. on-orbit segment to support U. S. and Russian extravehicular activity (EVA). In this plan, the U. S. Extravehicular Mobility Unit (EMU) and the Russian Orlan-M spacesuit system share a common vehicle water coolant loop. Since the two spacesuit systems use different biocide additives and contain different non-metallic materials in their respective cooling water loops, steps are being taken to insure that no deleterious effects occur due to the mixing of Orlan-M and EMU coolant water. This paper describes the activities of the Russian and U.S. International Space Station and EVA teams to understand the implications of using both countries' EVA systems in such a deeply interconnected manner. The paper discusses a current U.S. test program and Russian analyses, and presents results to-date in an ongoing issue.

The International Space Station (ISS) will include a Joint Airlock consisting of an Equipment Lock and Crewlock to be used by both the United States and Russia for conducting extravehicular activities (EVAs). The U.S. EVAs will be performed using the existing Shuttle extravehicular mobility unit (EMU). The Russian EVAs will be performed using the Orlan-M spacesuit. At the NASA/Johnson Space Center, a distributed set of hardware assemblies, referred to as Servicing and Performance Checkout Equipment (SPCE), are under development to support EVAs using either the EMU or Orlan-M spacesuit. This paper provides a description of each SPCE item along with a summary of the requirements and capabilities provided by the SPCE in support of EVA events from the ISS Joint Airlock.

The routine extravehicular activity (EVA) anticipated from the United States Space Station dictates that productivity be maximized for astronaut accessibility to information during the EVA, Ideally for Space Station EVA, this requires a “hands-free” operation, especially for intensive EVA scenarios such as satellite servicing and emergency or contingent operations. This hands-free access to information will be provided to the crewmember via a voice recognition & control system and a helmet-mounted projection display in the Space Station Extravehicular Mobility Unit (EMU). To demonstrate the capabilities of the combined system, a simulation program has been created which addreses the human factors required to effectively provide the crewmember with productive information during an EVA.

A greater number of manned extravehicular activities (EVAs) are anticipated for the United States Space Station compared to the few experienced on Space Shuttle missions. This requires the design of a new generation extravehicular mobility unit (EMU). Limitations inherent in the current EMU power supply--zinc silver-oxide batteries--include dry shelf-life, active wet-life, cycle-life, and recharge time, thus making its usage impractical for the Space Station. An alternative solution, a fuel cell energy storage system (FCESS), is being explored by Ergenics Power Systems, Inc. (EPSI), Wyckoff, N.J., with funding from NASA/Johnson Space Center. The ion-exchange membrane (IEM) fuel cell under consideration utilizes hydrogen stored as a metal hydride. EPSI has demonstrated experimentally that the fuel cell/hydride technology pair should be a primary candidate EMU power supply for its high volumetric/energy density and cycle life, quick recharge, durability, EMU integration, and safety.