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Technical Paper

Updating the Tools Used to Estimate Space Radiation Exposures for Operations: Codes, Models, and Interfaces

2002-07-15
2002-01-2457
In order to estimate the exposure to a crew in space, there are three essential steps to be performed: first, the ambient radiation environment at the vehicle must be characterized; second, the mass distribution properties of the vehicle, including the crewmembers themselves must be developed, and third a model of the interactions of space radiations with matter must be employed in order to characterize the radiation field at the dose point of interest. The Space Radiation Analysis Group (SRAG) at the NASA, Johnson Space Center carries the primary responsibility for the operational radiation protection support function associated with manned space flight. In order to provide support during the various planning, execution, and analysis/recording phase activities associated with a given mission, tools have been developed to allow rapid, repeatable calculations of exposure on orbit.
Technical Paper

Toxicological Assessment of the International Space Station Atmosphere, Part 2

2001-07-09
2001-01-2396
Space-faring crews must have safe breathing air throughout their missions to ensure adequate performance and good health. Toxicological assessment of air quality depends on the standards that define acceptable air quality, measurements of pollutant levels during the flight, and reports from the crew on their in-flight perceptions of air quality. Air samples from ISS flights 2A.2a, 2A.2b, 3A, and 4A were analyzed for trace pollutants. On average the air during each flight was safe for human respiration. However, there were reports from the crew that they experienced a headache when in certain areas, and strong odors were reported from specific locations of the ISS complex. Inspection of air samples in these locations suggested that several of the solvent-type pollutants (e.g. ethyl acetate, xylenes, and n-butanol) were present in concentrations that would cause a strong odor to be perceived by some individuals.
Technical Paper

The Lunar-Mars Life Support Test Project Phase III 90-day Test: The Crew Perspective

1998-07-13
981702
The Lunar-Mars Life Support Test Project (LMLSTP) Phase III test examined the use of biological and physicochemical life support technologies for the recovery of potable water from waste water, the regeneration of breathable air, and the maintenance of a shirt-sleeve environment for a crew of four persons for 91 days. This represents the longest duration ground-test of life support systems with humans performed in the United States. This paper will describe the test from the inside viewpoint, concentrating on three major areas: maintenance and repair of life support elements, the scientific projects performed primarily in support of the International Space Station, and numerous activities in the areas of public affairs and education outreach.
Technical Paper

The Lithium Hydroxide Management Plan for Removing Carbon Dioxide from the Space Shuttle while Docked to the International Space Station

2003-07-07
2003-01-2491
The Lithium Hydroxide (LiOH) management plan to control carbon dioxide (CO2) for the Shuttle while docked to the International Space Station (ISS) reduces the mass and volume needed to be launched. For missions before Flight UF-1/STS-108, the Shuttle and ISS each removed their own CO2 during the docked time period. To control the CO2 level, the Shuttle used LiOH canisters and the ISS used the Vozdukh or the Carbon Dioxide Removal Assembly (CDRA) with the Vozdukh being the primary ISS device for CO2 removal. Analysis predicted that both the Shuttle and Station atmospheres could be controlled using the Station resources with only the Vozdukh and the CDRA. If the LiOH canisters were not needed for the CO2 control on the Shuttle during the docked periods, then the mass and volume from these LiOH canisters normally launched on the Shuttle could be replaced with other cargo.
Technical Paper

The Food System for the International Space Station: The First Five Increments

2003-07-07
2003-01-2426
The International Space Station (ISS) has been continuously crewed for more than 2 years. One of the major systems for crew health, performance and psychological support is the food system. This paper documents the mechanics of implementation for the ISS food system, with emphasis on the U.S. portion of that system, and also provides some performance feedback received from the first 5 increment crews. Menu composition and planning, food stowage, on orbit preparation, shipments, and inventory control are also described.
Technical Paper

Summary of Resources for the International Space Station Environmental Control and Life Support System for Core Complete Modules

2004-07-19
2004-01-2386
The Core Complete Environmental Control and Life Support (ECLS) system for the International Space Station (ISS) will consist of components and subsystems in both the United States (U.S.) and International Partner elements which together will perform the functions of Temperature and Humidity Control (THC), Atmosphere Control and Supply (ACS), Atmosphere Revitalization (AR), Water Recovery and Management (WRM), Fire Detection and Suppression (FDS), and Vacuum System (VS) for the station. Due to limited resources available on ISS, detailed attention is given to minimizing and tracking all resources associated with all systems, beginning with estimates during the hardware development phase through measured actuals when flight hardware is built and delivered. A summary of resources consumed by the current and by the addition of future U.S.
Technical Paper

Summary of Resources for the International Space Station Environmental Control and Life Support System

2003-07-07
2003-01-2596
The assembly complete Environmental Control and Life Support (ECLS) system for the International Space Station (ISS) will consist of components and subsystems in both the U.S. and International partner elements which together will perform the functions of Temperature and Humidity Control (THC), Atmosphere Control and Supply (ACS), Atmosphere Revitalization (AR), Water Recovery and Management (WRM), Fire Detection and Suppression (FDS), and Vacuum System (VS) for the station. Due to limited resources available on ISS, detailed attention is given to minimizing and tracking all resources associated with all systems, beginning with estimates during the hardware development phase through measured actuals when flight hardware is built and delivered. A summary of resources consumed by the current on-orbit U.S. ECLS system hardware is presented, including launch weight, average continuous and peak power loads, on-orbit volume and resupply logistics.
Technical Paper

Space Station Crew Interface Specifications and Standards

1985-10-14
851801
A program has been initiated to develop a single set of man/system integration standards, requirements, and guidelines to design hardware and systems with which the space missions crew will interact. This paper describes the background, key issues, and methodology to be used in developing these standards. Included in the methodology is data collection and requirements analysis as well as technical monitoring and review, which includes a government/industry technical advisory group. This paper also briefly describes work performed on the Space Station Human Productivity study.
Technical Paper

Space Shuttle Launch Entry Suit Thermal Performance Evaluation

1993-07-01
932297
Comments of the Space Shuttle crew indicate that the Launch Entry Suit (LES) may provide inadequate cooling before launch and after reentry. During these periods some crewmembers experienced thermal discomfort induced by localized cabin heating, middeck experiments, and crewmembers' body heat and humidity. The NASA Johnson Space Center(JSC) Crew and Thermal System Division (CTSD) executed a two phase study, analysis and testing, to investigate this problem. The analysis phase used a computer model of the LES to study the transient heat dissipation and temperature response under the various Space Shuttle flight cabin environments. After the completion of the analysis, the testing phase was conducted to collect the engineering data in order to validate the analysis results. Due to the constraint of the test facility, the test was conducted on the air cooled techniques only. This paper presents the analytical model, its solution and an evaluation and summary of the test results.
Technical Paper

Requirements and Potential for Enhanced EVA Information Interfaces

2003-07-07
2003-01-2413
NASA has long recognized the advantages of providing improved information interfaces to EVA astronauts and has pursued this goal through a number of development programs over the past decade. None of these activities or parallel efforts in industry and academia has so far resulted in the development of an operational system to replace or augment the current extravehicular mobility unit (EMU) Display and Controls Module (DCM) display and cuff checklist. Recent advances in display, communications, and information processing technologies offer exciting new opportunities for EVA information interfaces that can better serve the needs of a variety of NASA missions. Hamilton Sundstrand Space Systems International (HSSSI) has been collaborating with Simon Fraser University and others on the NASA Haughton Mars Project and with researchers at the Massachusetts Institute of Technology (MIT), Boeing, and Symbol Technologies in investigating these possibilities.
Technical Paper

Reduced Gravity and Ground Testing of a Two-Phase Thermal Management System for Large Spacecraft

1988-07-01
881084
An experiment was performed to observe flow regimes and measure pressure drops of two-phase (liquid/vapor) flow and condensation in reduced gravity. Testing was conducted aboard the NASA-JSC KC-135 reduced gravity aircraft using a prototype two-phase thermal management system for large spacecraft. A clear section of two-phase line enabled visual and photographic observation of the flow regimes. The two-phase mixture was generated by pumping nearly saturated liquid refrigerant 114 through an evaporator and adding heat through electric heaters. The resultant two-phase flow was varied by changing the evaporator heat load, creating qualities from 0.05 to 0.80. Visual and photographic observation of vapor condensation was also made through a clear cover on the system condenser. During the flight tests, the experiment hardware was exposed to gravitational acceleration ranging from near-zero to 1.8 g's.
Technical Paper

Quality Function Deployment for the Shoulder Section of the Space Suit

2005-07-11
2005-01-3017
Spacesuit shoulder mobility is critical in performing EVA tasks. In addition, risk of failure must be minimized and injuries during operations and training eliminated. The pressure suit design elements that control shoulder mobility interact strongly and in complex ways with many aspects of the pressure suit and system design and are constrained by anthropometric factors. To properly develop the problem statement for the shoulder section in a new suit design that is appropriate for a return to the Moon and eventual exploration of Mars, a Quality Function Deployment (QFD) is under development. QFD is a powerful and widely used method to define your customers, determine their needs, benchmark the competition, and define engineering parameters and targets, that when met, will lead to a successful product. Since many of the requirements for the next generation suit are unknown, the QFD will continually be updated.
Technical Paper

Project Orion, Environmental Control and Life Support System Integrated Studies

2008-06-29
2008-01-2086
Orion is the next vehicle for human space travel. Humans will be sustained in space by the Orion subystem, environmental control and life support (ECLS). The ECLS concept at the subsystem level is outlined by function and technology. In the past two years, the interface definition with other subsystems has increased through different integrated studies. The paper presents the key requirements and discusses three recent studies (e.g., unpressurized cargo) along with the respective impacts on the ECLS design moving forward.
Technical Paper

Micrometeoroid Penetration Hazards Assessment for the Shuttle EMU

1999-07-12
1999-01-1963
Micrometeoroid and orbital debris (MMOD) penetration hazards have been a concern for the large number of EVA’s (Extravehicular Activities) expected during the assembly and operation of the International Space Station (ISS). Earlier studies have shown large uncertainties in estimated spacesuit penetration risks. This paper reports the results of recent tests and analyses that have significantly expanded the Shuttle EMU (Extravehicular Mobility Unit) hypervelocity penetration database and clarified our understanding of the associated risks. The results of testing have been used to develop improved estimates of the cumulative risk of penetration during EVA's through the first ten years after the beginning of ISS construction. These analyses have shown that the risks of MMOD penetration during EVA will be somewhat less than the risk of a critical penetration of the ISS itself over the same ten-year period.
Technical Paper

Methodology and Assumptions of Contingency Shuttle Crew Support (CSCS) Calculations Using ISS Environmental and Life Support Systems

2006-07-17
2006-01-2061
The current International Space Station (ISS) Environmental Control and Life Support (ECLS) system is designed to support an ISS crew size of three people. The capability to expand that system to support nine crew members during a Contingency Shuttle Crew Support (CSCS) scenario has been evaluated. This paper describes how the ISS ECLS systems may be operated for supporting CSCS, and the durations expected for the oxygen supply and carbon dioxide control subsystems.
Technical Paper

Mark III Space Suit Mobility: A Reach Evaluation Case Study

2007-06-12
2007-01-2473
A preliminary assessment of the reach envelope and field of vision (FOV) for a subject wearing a Mark III space suit was requested for use in human-machine interface design of the Science Crew Operations and Utility Testbed (SCOUT) vehicle. The reach and view of two suited and unsuited subjects were evaluated while seated in the vehicle using 3-dimensional position data collected during a series of reaching motions. Data was interpolated and displayed in orthogonal views and cross-sections. Compared with unsuited conditions, medio-lateral reach was not strongly affected by the Mark III suit, whereas vertical and antero-posterior reach were inhibited by the suit. Lateral FOV was reduced by approximately 40° in the suit. The techniques used in this case study may prove useful in human-machine interface design by providing a new means of developing and displaying reach envelopes.
Technical Paper

Life Sciences Space Biology Project Planning

1988-07-01
881075
Life sciences research facilities planned for the U.S. Space Station will accommodate life sciences investigations addressing the influence of microgravity on living organisms. Current projects within the Life Sciences Space Station Program (LSSSP), the Life Sciences Space Biology (LSSB) and Extended Duration Crew Operations (EDCO) projects, will explore the physiological, clinical, and sociological implications of long duration space flight on humans and the influence of microgravity on other biological organisms/systems. Initially, the primary research will emphasize certifying man for routine 180-day stays on the Space Station. Operational crew rotations of 180 days or more will help reduce Space Station operational costs and minimize the number of Space Transportation System (STS) shuttle flights required to support Space Station.
Journal Article

Lessons Learned from the International Space Station (ISS) Environmental Control and Life Support System (ECLSS) Water Subsystem

2008-06-29
2008-01-2008
The International Space Station (ISS) has served as an excellent test bed for the implementation and integration of several life support systems, and has offered many lessons that can be applied to future vehicles and program. This paper focuses on those lessons learned within the Environmental Control and Life Support (ECLS) Water Subsystem, which have dictated on-orbit system performance and forced many operational controls. These include lessons on the need for precise documentation and testing, pros and cons of different types of storage containers, and the need for designing systems to have accessibility and flexibility. This paper describes the issues encountered on ISS and suggests solutions for future systems in the form of recommendations and questions posed to the future designers.
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