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Gas Injection Molding (GIM) is a process by which External Tank (ET) components receive Super Light Ablator (SLA) through pressurized injection of ablator into a vented mold assembly. Component surfaces are cleaned and coated with a silicone primer. Each part is transferred to the adhesive work station where a pre-mixed batch of adhesive is obtained and applied to the primer substrate in a smooth continuous coating. After injection is complete, the mold is processed through a heat cycle, the panel representative of the component is scrutinized for acceptable density and tensile strength values. The component is inspected for dimensional tolerances and visual inspection is performed.

Extensive development testing to support the design of the Space Station Freedom (SSF) Carbon Dioxide (CO2) Reduction Assembly (CReA) has been conducted. Both dual and single reactor eight-person capacity systems, supported by experimental test setups, have been used to broaden the design data base. Multiple catalysts were evaluated. Of significant importance was data that showed that operation of the Bosch reaction at elevated pressure 150-205 kPa (7-15 psig) provides significant increases in process efficiency. These improvements significantly reduce the recycle gas rate necessary to achieve a 99%+ CO2 reduction efficiency. Data presented illus-trates the improvements realized and defines the benefits that the new technology offers in terms of savings in power, weight and volume as illustrated by the SSF CReA.

This is an assessment of Aerospace Technology in Japan, the national vision supporting it and the strategy underlies it's ultimate purpose. It includes a comparison of the organizations and missions of the two principle aerospace agencies: One, the Institute of Space and Astronautical Science (ISAS); and, two, the National Space Development Agency (NASDA). Included are the launch capabilities and deep space facilities of ISAS, at Kagoshima Space Center (KSC) in Uchinoura on Kyushu island; and the NASDA Tanegashima Space Center (TSC) on Tanegashima Island. Also included are the design and development history of domestic Nippon launch and space vehicles, beginning with the licensing of the United States Thor-Delta rocket technology and including the design of the domestic H-I second and third stages and the all domestic H-II vehicles.

This paper presents preliminary result in a flexible fixture solution for airframe assembly comprising a modular steel framework called Box-joint and flexible tooling modules called Hexapods. The solution is comprises a framework that is screwed together instead of welding beams together, which enables re-building the framework when performing change-over in a more extensive reconfiguration. The Hexapods are parallel legged passive fixture stands that can change their configuration to facilitate easy setup in a change-over between handle different assemblies. A solution to configure the Hexapods manually is described. The investment cost can be kept low by using a metrology system to provide for high accuracy in the tool configuration process instead of using precision parts in the fixture system.

Manufacturing design processes for complex systems, like advanced fighter aircraft, require a special emphasis on human interactions to technical fabrication and assembly functions. The role of the human is being refined as manufacturing processes become more sophisticated. The infusion of human performance requirements into manufacturing design is a sensible approach to achieving efficient, cost-effective manufacturing processes. We will discuss the early input of ergonomics criteria and the benefits of addressing the human interaction in the manufacturing design process.

In a harmonized ESA/NIVR project the performance of membrane gas absorption for the simultaneous removal of carbon dioxide and moisture has been determined experimentally at carbon dioxide and humidity concentration levels representative for spacecraft conditions. Performance data at several experimental conditions have been collected. Removal of moisture can be controlled by the temperature of the absorption liquid. Removal of carbon dioxide is slightly affected by the temperature of the absorption liquid. Based on these measurements a conceptual design for a carbon dioxide and humidity control system for the Crew Transport Vehicle (CTV) is made. For the regeneration step in this design a number of assumptions have been made. The multifunctionality of membrane gas absorption makes it possible to combine a number of functions in one compact system.

Real time knowledge of the metabolic workload of an astronaut during an Extra-Vehicular Activity (EVA) can be instrumental for space suit research, design, and operation. Three indirect calorimetry approaches were developed to determine the metabolic workload of a subject in an open-loop space suit analogue. A study was conducted to compare the data obtained from three sensors: oxygen, carbon dioxide, and heart rate. Subjects performed treadmill exercise in an enclosed helmet assembly, which simulated the contained environment of a space suit while retaining arm and leg mobility. These results were validated against a standard system used by exercise physiologists. The carbon dioxide sensor method was shown to be the most reliable and a calibrated version of it will be integrated into the MX-2 neutral buoyancy space suit analogue.

During the last years extensive work has been done to design and develop the Closed-Loop Air Revitalization System ARES. The potential of ARES e.g. as part of the ISS ECLSS is to significantly reduce the water upload demand and to increase the safety of the crew by reducing dependence on re-supply flights. The design is adapted to the interfaces of the new base lined Russian MLM module as possible location for a future installation of ARES. Due to the lack of orbital support equipment and interfaces to a waste water bus, to a feed water supply line and due to the availability of only one single vent line it was necessary to make the ARES process water loop as independent as possible from the host vehicle. Another optimization effort was to match the CO2 desorption profile with the available hydrogen flow to achieve a sufficient water recovery performance, while meeting all related safety requirements, minimizing complexity and improving reliability.

The Carbon Dioxide Removal Assembly (CDRA) is a part of the International Space Station (ISS) Environmental Control and Life Support (ECLS) system. The CDRA provides carbon dioxide (CO2) removal from the ISS on-orbit modules. Currently, the CDRA is the secondary removal system on the ISS, with the primary system being the Russian Vozdukh. Within the CDRA are two Desiccant/Adsorbent Beds (DAB), which perform the carbon dioxide removal function. The DAB adsorbent containment approach required improvements with respect to adsorbent containment. These improvements were implemented through a redesign program and have been implemented on units on the ground and returning from orbit. This paper presents a DAB design modification implementation description, a hardware performance comparison between the unmodified and modified DAB configurations, and a description of the modified DAB hardware implementation into the on-orbit CDRA.

The Space Shuttle's Solid Rocket Motor (SRM) processing equipment for motor assembly at NASA's John F. Kennedy Space Center, was designed in the mid 1980's. Consequently, the data acquisition systems (DAS) and associated processors are obsolete and unreliable. The SRM Stacking Enhancement Tool (SSET) project was initiated to update and automate the motor assembly process. The SSET project is replacing the existing segment processing data acquisition panels and incorporating the Segment Shape Prediction Program (SSPP) into a single panel providing updated processors and an intuitive “smart” graphical user interface with the capability of recording all data. The SSET project is also providing a Calibration Confirmation Control System (CCCS) that will electronically retain the instruments calibration information with the instrument.

Carbon dioxide removal from the Space Station Freedom atmosphere is an essential part of crew life support. Freedom must utilize carbon dioxide removal systems to prevent crew asphyxiation. This paper describes the predevelopment operational system test (POST) four-bed molecular sieve carbon dioxide removal assembly, its operation, and its key components. Many approaches are available to effect carbon dioxide removal, and include both regenerative and non-regenerative methods. To minimize Freedom logistics support and to close the cabin oxygen loop, regenerative systems will be relied upon. The Freedom carbon dioxide removal assembly will selectively remove carbon dioxide from an air supply stream, preventing carbon dioxide accumulation within the cabin, and then concentrate it for downstream processing in a carbon dioxide reduction system where oxygen eventually is recovered. Freedom will utilize a regenerative four-bed molecular sieve system for the carbon dioxide removal assembly.

A filter assembly which is incorporated into the Russian Trace Contaminant Control Assembly was tested for removal of airborne trace chemical contaminants in a closed loop 9 m3 system. Given contaminant loading rates and maximum allowable atmospheric concentrations, the Russian system was able to maintain system air concentrations below maximum allowable limits. This was achieved for both a new filter system and for a system where a part of it was pre-loaded to emulate 3 years of system age.

Methane-filled heat pipes have been developed and qualified for the SCIAMACHY thermal bus assembly. The heat pipes provide an efficient heat transfer in the temperature range 100-160 K. Extensive qualification testing has been performed. The thermal bus assembly is part of the Thermal Bus Unit (TBU) of the SCIAMACHY Radiant Cooler.

Molecular sieve carbon dioxide removal systems are a proven and reliable method for the control of carbon dioxide in a closed environment. Carbon dioxide control was provided by a molecular sieve unit for Skylab. Currently, the carbon dioxide removal assembly (CDRA) is being manufactured by AlliedSignal for Boeing and will be utilized for carbon dioxide removal on the International Space Station (ISS). Development testing has been performed on CDRA and different power saving operation modes have been investigated. Also as part of the Lunar-Mars Life Support Test Project (LMLSTP) initiative, a research four-bed molecular sieve (4BMS) system has been tested at NASA Johnson Space Center. The most recent test was Phase IIA, which was a 60-day test that focused on integration testing of representative ISS hardware with four humans living inside a closed chamber.

The Heat Rejection Subsystem (HRS) Radiators Orbital Replaceable Unit (ORU) for the International Space Station has undergone thermal vacuum qualification testing at NASA Plum Brook Station, Space Power Facility in Ohio. The testing was conducted from December 1996 through January 1997 and October 4 through 18, 1997. This testing included confirmation of the heater control assembly (HCA) and heater performance that was initially tested during December 1996 through January 1997. Deployment system functional operations were tested for both hot and cold conditions using both the Integrated Motor Control Assembly (IMCA) and the Extravehicular Activity (EVA) drive.

The Photovoltaic Radiator (PVR) is designed to reject waste heat of the Early External Active Thermal Control System (EEATCS) and the Photovoltaic Thermal Control System (PV TCS) of the International Space Station (ISS). Two EEATCS PVR units and one PV TCS PVR unit will be on the Assured Early Research (AER) phase of the ISS and all four PV TCS PVR units will be on the assembly complete configuration of the ISS. Thermal environments of the AER mission and assembly complete configuration present challenging thermal designs to maintain the EEATCS and PV TCS PVR units functioning within the temperature operating limits of the structural components and the ammonia fluid.

Heat rejection requirements for the Photovoltaic Radiator (PVR) are derived from the Photovoltaic Module power generation and storage system electrical power requirements imposed by NASA. The requirement has been added to provide heat rejection for the Early Extended Active Thermal Control System (EEATCS) to support the Assured Early Research phase of the International Space Station (ISS) Mission. Early mission requirements have resulted in two of the units being coated with a silver Teflon tape. The original Thermal Control System (TCS) requirements require one of the units to be coated with Z-93. Qualification testing of the PVR includes both single panel and assembly level testing. Single panel testing is part of a qualification test program, which is designed to verify the pressure drop and thermal performance of the PVR.

The paper presents the results of ground and flight (on OSS Mir) tests of an updated purification assembly of the WRS-C system outfitted with a filter-reactor. The tests have proved that the filter-reactor oxidizes effectively basic organic contaminants in humidity condensate including ethyleneglycol to ones that easily undergo sorption, enables the operation of the recovery system in the event of an off-design increase in organic contaminants in condensate and significantly improves the lifetime of the purification assembly. The data obtained confirm a wise selection of the purification assembly hardware for the system for water recovery from humidity condensate WRS-CM for the ISS service module.

A multi-element fixed control volume integrated air interchange system performance computer model has been developed and upgraded for the evaluation/assessment of atmospheric characteristics inside the crew compartments of the mated Orbiter and International Space Station (ISS). In order to ensure a safe, comfortable, and habitable environment for all the astronauts during the Orbiter/ISS docked period, this model was utilized to conduct the analysis for supporting the early ISS assembly missions. Two ISS assembly missions #2A and #4A were selected and analyzed.

To address basic cell biology questions such as “Can cells respond to a gravity stimulus?”, a Cell Culture Unit (CCU) is being developed for use in the International Space Station. The CCU will accommodate diverse specimen types (animal, plant, and microbial cells; tissues; aquatic organisms) in up to twenty-four cell specimen chambers. The environmental conditions (e.g. temperature, pH, gas concentrations) will be maintained by medium recirculation and renewal, and gas and heat exchange. The CCU will also provide for the addition of experimental agents (e.g. growth factors), automated sampling, and monitoring of the specimens by video microscopy. Microgravity experiments will be performed using the CCU within the Habitat Holding Rack (HHR); a CCU within the Space Station Centrifuge will serve as an on-board unit-gravity control.