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The National Aeronautics and Space Administration (NASA) is interested in characterizing the responses of THOR (test device for human occupant restraint) anthropometric test device (ATD) to representative loading acceleration pulse s. Test conditions were selected both for their applicability to anticipated NASA landing scenarios, and for comparison to human volunteer data previously collected by the United States Air Force (USAF). THOR impact testing was conducted in the fore-to-aft frontal (-x) and in the upward spinal (-z) directions with peak sled accelerations ranging from 8 to 12 G and rise times of 40, 70, and 100ms. Each test condition was paired with historical huma n data sets under similar test conditions that were also conducted on the Horizontal Impulse Accelerator (HIA). A correlation score was calculated for each THOR to human comparison using CORA (CORrelation and Analysis) software.

The aim of this study was to explore if fingernail delamination injury following EMU glove use may be caused by compression-induced blood flow occlusion in the finger. During compression tests, finger blood flow decreased more than 60%, however this occurred more rapidly for finger pad compression (4 N) than for fingertips (10 N). A pressure bulb compression test resulted in 50% and 45% decreased blood flow at 100 mmHg and 200 mmHg, respectively. These results indicate that the finger pad pressure required to articulate stiff gloves is more likely to contribute to injury than the fingertip pressure associated with tight fitting gloves.

A system of amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and is baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of the technology, which was performed in a representative environment with simulated human metabolic loads. The next step in developmental testing at JSC was to use real human loads in the spring of 2008.

The subjective aspects of comfort in three different cooling garments, the MACS-Delphi, Russian Orlan, and LCVG were evaluated. Six subjects (4 males and 2 females) were tested in separate sessions in each garment and in one of two environmental chamber conditions: 24°C and 35°C. Subjects followed a staged exercise/rest protocol with different levels of physical exertion at different stages. Thermal comfort and heat perception were assessed by ratings on visual analog scales. Ratings of physical comfort of the garment and also garment flexibility in positions simulating movements during planetary exploration were also obtained. The findings indicated that both overall thermal comfort and head thermal comfort were rated highest in the MACS-Delphi at 24°C. The Orlan was rated lowest on physical comfort and less flexible in different body positions.

In a crewed spacecraft environment, atmospheric carbon dioxide (CO2) and moisture control are crucial. Hamilton Sundstrand has developed a stable and efficient amine-based CO2 and water vapor sorbent, SA9T, that is well suited for use in a spacecraft environment. The sorbent is efficiently packaged in pressure-swing regenerable beds that are thermally linked to improve removal efficiency and minimize vehicle thermal loads. Flows are controlled with a single spool valve. This technology has been baselined for the new Orion spacecraft, but additional data was needed on the operational characteristics of the package in a simulated spacecraft environment. One unit was tested with simulated metabolic loads in a closed chamber at Johnson Space Center during the latter part of 2006. Those test results were reported in a 2007 ICES paper.

The Orion crew module (CM) is being designed to perform survivable land and water landings. There are many issues associated with post-landing crew survival. In general, the most challenging of the realistic Orion landing scenarios from an environmental control standpoint is the off-nominal water landing. Available power and other consumables will be very limited after landing, and it may not be possible to provide full environmental control within the crew cabin for very long after splashdown. Given the bulk and thermal insulation characteristics of the crew-worn pressure suits, landing in a warm tropical ocean area would pose a risk to crew survival from elevated core body temperatures, if for some reason the crewmembers were not able to remove their suits and/or exit the vehicle. This paper summarizes the analyses performed and conclusions reached regarding post-landing crew survival following a water landing, from the standpoint of the crew's core body temperatures.

Recovery of potable water from wastewater is essential for the success of long-term manned missions to the moon and Mars. Honeywell International and the team consisting of Thermodistillation Company (Kyiv, Ukraine) and NASA Johnson Space Center (JSC) Crew and Thermal Systems Division are developing a wastewater processing subsystem that is based on centrifugal vacuum distillation. The Wastewater Processing Cascade Distillation Subsystem (CDS) utilizes an innovative and efficient multi-stage thermodynamic process to produce purified water. The rotary centrifugal design of the system also provides gas/liquid phase separation and liquid transport under microgravity conditions. A five-stage prototype of the subsystem was built, delivered and integrated into the NASA JSC Advanced Water Recovery Systems Development Facility for development testing.

Carbon dioxide (CO2) removal technology development for portable life support systems (PLSS) has traditionally concentrated in the areas of solid and liquid chemical sorbents and semi-permeable membranes. Most of these systems are too heavy in gravity environments, require prohibitive amounts of consumables for operation on long term planetary missions, or are inoperable on the surface of Mars due to the presence of a CO2 atmosphere. This paper describes the effort performed to mature an innovative CO2 removal technology that meets NASA's planetary mission needs while adhering to the important guiding principles of simplicity, reliability, and operability. A breadboard cryogenic carbon dioxide scrubber for an ejector-based cryogenic PLSS was developed, designed, and tested. The scrubber freezes CO2 and other trace contaminants out of expired ventilation loop gas using cooling available from a liquid oxygen (LOX) based PLSS.

This project investigates methods to capture an astronaut's exhaled carbon dioxide (CO2) before it becomes diluted with the high volumetric oxygen flow present within a space suit. Typical expired breath contains CO2 partial pressures (pCO2) in the range of 20-35 mm Hg (.0226-.046 atm). This research investigates methods to capture the concentrated CO2 gas stream prior to its dilution with the low pCO2 ventilation flow. Specifically this research is looking at potential designs for a collection cup for use inside the space suit helmet. The collection cup concept is not the same as a breathing mask typical of that worn by firefighters and pilots. It is well known that most members of the astronaut corps view a mask as a serious deficiency in any space suit helmet design. Instead, the collection cup is a non-contact device that will be designed using a detailed Computational Fluid Dynamic (CFD) analysis of the ventilation flow environment within the helmet.

Development of new air revitalization system (ARS) technology can initially be performed in a subscale laboratory environment, but in order to advance the maturity level, the technology must be tested in an end-to-end integrated environment. The Air Revitalization Technology Evaluation Facility (ARTEF) at the NASA Johnson Space Center (JSC) serves as a ground test bed for evaluating emerging ARS technologies in an environment representative of spacecraft atmospheres. At the center of the ARTEF is a hypobaric chamber which serves as a sealed atmospheric chamber for closed loop testing. A Human Metabolic Simulator (HMS) was custom-built to simulate the consumption of oxygen, and production of carbon dioxide, moisture and heat by up to eight persons. A variety of gas analyzers and dew point sensors are used to monitor the chamber atmosphere and the process flow upstream and downstream of a test article. A robust vacuum system is needed to simulate the vacuum of space.

Protecting astronauts from space radiation exposure is an important challenge for mission design and operations for future exploration-class and long-duration missions. Crew members are exposed to sporadic solar particle events (SPEs) as well as to the continuous galactic cosmic radiation (GCR). If sufficient protection is not provided the radiation risk to crew members from SPEs could be significant. To improve exposure risk estimates and radiation protection from SPEs, detailed evaluations of radiation shielding properties are required. A model using a modern CAD tool ProE™, which is the leading engineering design platform at NASA, has been developed for this purpose. For the calculation of radiation exposure at a specific site, the cosine distribution was implemented to replicate the omnidirectional characteristic of the 4π particle flux on a surface.

In a crewed spacecraft environment, atmospheric carbon dioxide (CO2) and moisture control are crucial. Hamilton Sundstrand has developed a stable and efficient amine-based CO2 and water vapor sorbent, SA9T, that is well suited for use in a spacecraft environment. The sorbent is efficiently packaged in pressure-swing regenerable beds that are thermally linked to improve removal efficiency and minimize vehicle thermal loads. Flows are all controlled with a single spool valve. This technology has been baselined for the new Orion spacecraft. However, more data was needed on the operational characteristics of the package in a simulated spacecraft environment. A unit was therefore tested with simulated metabolic loads in a closed chamber at Johnson Space Center during the last third of 2006. Tests were run at a variety of cabin temperatures and with a range of operating conditions varying cycle time, vacuum pressure, air flow rate, and crew activity levels.

Meeting radiation protection requirements during EVA is predominantly an operational issue with some potential considerations for temporary shelter. The issue of spacesuit shielding is mainly guided by the potential of accidental exposure when operational and temporary shelter considerations fail to maintain exposures within operational limits. In this case, very high exposure levels are possible which could result in observable health effects and even be life threatening. Under these assumptions, potential spacesuit radiation exposures have been studied using known historical solar particle events to gain insight on the usefulness of modification of spacesuit design in which the control of skin exposure is a critical design issue and reduction of blood forming organ exposure is desirable.

As NASA is preparing to extend man's reach into space, it is expected that astronauts will be required to spend more and more time exposed to the hazards of performing Extra-Vehicular Activity (EVA). One of these hazards includes the risk of the space suit bladder being penetrated by hypervelocity micrometeoroid and orbital debris (MMOD) particles. Therefore, it has become increasingly important to investigate new ways to improve the protectiveness of the current Extravehicular Mobility Unit (EMU) against MMOD penetration. ILC Dover conducted a NASA funded study into identifying methods of improving the current EMU protection. The first part of this evaluation focused on identifying how to increase the EMU shielding, selecting materials to accomplish this, and testing these materials to determine the best lay-up combinations to integrate into the current thermal micrometeoroid garment (TMG) design.

An ADvanced Automotive Manikin (ADAM) developed at the National Renewable Energy Laboratory (NREL) is used to evaluate NASA’s liquid cooling garments (LCGs) used in advanced spacesuits. The manikin has 120 separate heated/sweating zones and is controlled by a finite-element physiological model of the human thermo-regulatory system. Previous testing showed the thermal sensation and comfort followed expected trends as the LCG inlet fluid temperature was changed. The Phase II test data demonstrates the repeatability of ADAM by retesting the baseline LCG. Skin and core temperature predictions using ADAM in an LCG/arctic suit combination are compared to NASA physiological data to validate the manikin/model. An additional Orlan LCG configuration is assessed using the manikin and compared to the baseline LCG.

The challenges of missions to the Moon and Mars presents NASA with the need for more advanced life support systems, including better technologies for CO2 removal in spacecraft atmospheres and extravehicular mobility units (EMU). Amine-coated single wall carbon nanotubes (SWCNT) have been proposed as a potential solution because of their high surface area and thermal conductivity. Initial research demonstrated the need for functionalization of SWCNT to obtain optimal adherence of the amine to the SWCNT support phase [1]. Recent efforts focus on the development of new methods to chemically bond amines to SWCNT. Synthesis and characterization methods for these materials are discussed and some preliminary materials characterization data are presented. The CO2 adsorption capacity for several versions of SWCNT supported amine-based CO2 scrubber materials is also determined.

Metabolically produced carbon dioxide (CO2) removal in spacesuit applications has traditionally been accomplished utilizing non-regenerative Lithium Hydroxide (LiOH) canisters. In recent years, regenerative Metal Oxide (MetOx) has been developed to replace the Extravehicular Mobility Unity (EMU) LiOH canister for extravehicular activity (EVA) missions in micro-gravity, however, MetOx may carry a significant weight burden for potential use in future Lunar or planetary EVA exploration missions. Additionally, both of these methods of CO2 removal have a finite capacity sized for the particular mission profile. Metabolically produced water vapor removal in spacesuits has historically been accomplished by a condensing heat exchanger within the ventilation process loop of the suit life support system.

Recent efforts have been pursued to establish the usefulness of Space Shuttle Orbiter lithium hydroxide (LiOH) canisters beyond their certified two-year shelf life, at which time they are currently considered “expired.” A stockpile of Orbiter LiOH canisters are stowed on the International Space Station (ISS) as a backup system for maintaining ISS carbon dioxide Canisters with older (CO2) control. Canister with older pack dates must routinely be replaced with newly packed canisters off-loaded from the Orbiter Middeck. Since conservation of upmass is critical for every mission, the minimization of canister swap-out rate is paramount. LiOH samples from canisters with expired dates that had been returned from the ISS were tested for CO2 removal performance at the NASA Johnson Space Center (JSC) Crew and Thermal Systems Division (CTSD). Through this test series and subsequent analysis, performance degradation was established.

A cryofreezer system is being evaluated as a new method of compressing and storing carbon dioxide (CO2) in an Advanced Life Support (ALS) Environmental Control and Life Support System (ECLSS). A cryocooler is used to provide cold temperatures and heat removal while CO2 freezes and accumulates around a coldtip. The CO2 can then be stored as a liquid or high-pressure gas after it has been accumulated. This system was originally conceived as an In-Situ Resource Utilization (ISRU) application for collecting CO2 from the Mars atmosphere to be converted to methane fuel with a Sabatier reaction. In the ALS application, this system could collect CO2 from the International Space Station (ISS) Carbon Dioxide Removal Assembly (CDRA) for delivery to the Sabatier reactor. The Sabatier reaction is an important part of proposed Air Revitalization System (ARS) for ALS, and technology sharing is often possible between ISRU and ARS applications in CO2 processing systems.

The Self Contained Atmospheric Protective Ensemble (SCAPE) suits, worn at the Kennedy Space Center (KSC) have been updated from the original 1970's design. The suits were renamed Propellant Handlers Ensemble (PHE) but are still commonly referred to as SCAPE. Several modifications to the suit were done over the last 20 years to improve the design for operational use. However, anthropometric changes in the user population over time have not been addressed. The following study addressed anthropometric concerns in the current SCAPE population. It was found that all suits had at least one area in which the recommended upper limit was exceeded by technicians. The most common areas to exceed the upper limit were: waist circumference, chest circumference and upper thigh circumference. Forearm circumference posed the least concern unless using long gauntlet glove which cause the twist lock ring to be located at the forearm rather than the wrist.