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This paper focuses on an Air Evaporation Subsystem component of the Water Recovery System being developed at the Johnson Space Center in the Crew and Thermal Systems Division. Specifically, the focus is on the design and testing of the next generation of Air Evaporation Subsystem Engineering Development Unit built after the Lunar-Mars Life Support Test Project Phase III 91day test. The primary objective of testing this next generation Air Evaporation Subsystem was to demonstrate its performance as a Reverse Osmosis brine treatment subsystem by looking at the condensate quality produced from Reverse Osmosis brine and the power required to process the Reverse Osmosis brine. The secondary objectives were to develop optimal operating conditions, to optimize the use of a consumable wick and to retain as much operational data as possible through instrumentation.

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.

A thermal analysis of the compressible carbon dioxide (CO2) flow for the Portable Fire Extinguisher (PFE) system has been performed. A SINDA/FLUINT model has been developed for this analysis. The model includes the PFE tank and the Temporary Sleep Station (TeSS) nozzle, and both have an initial temperature of 72 °F. In order to investigate the thermal effect on the nozzle due to discharging CO2, the PFE TeSS nozzle pipe has been divided into three segments. This model also includes heat transfer predictions for PFE tank inner and outer wall surfaces. The simulation results show that the CO2 discharge rates and component wall temperatures fall within the requirements for the PFE system. The simulation results also indicate that after 50 seconds, the remaining CO2 in the tank may be near the triple point (gas, liquid and solid) state and, therefore, restricts the flow.

The Advanced Life Support Research and Technology Development Metric, or Metric, for Government Fiscal Year 2002 provides a measure of the equivalent system mass for a life support system using the “best” available advanced technologies compared to the equivalent system mass for a life support system using technologies from International Space Station. The present paper details the assumed life support system configurations and algorithm used to compute the Metric. Additionally, various peripheral issues of importance are mentioned.

A key component of an Advanced Life Support (ALS) system is the solid waste handling system. One of the most important data sets for determining what solid waste handling technologies are needed is a solid waste model. A preliminary solid waste model based on a six-person crew was developed prior to the 2000 Solid Waste Processing and Resource Recovery (SWPRR) workshop. After the workshop, comments from the ALS community helped refine the model. Refinements included better estimates of both inedible plant biomass and packaging materials. Estimates for Extravehicular Mobility Unit (EMU) waste, water processor brine solution, as well as the water contents for various solid wastes were included in the model refinement efforts. The wastes were re-categorized and the dry wastes were separated from wet wastes. This paper details the revised model as of the end of 2001. The packaging materials, as well as the biomass wastes, vary significantly between different proposed Mars missions.

Long duration missions pose substantial new challenges for solid waste management in Advanced Life Support (ALS) systems. These possibly include storing large volumes of waste material in a safe manner, rendering wastes stable or sterilized for extended periods of time, and/or processing wastes for recovery of vital resources. This is further complicated because future missions remain ill-defined with respect to waste stream quantity, composition and generation schedule. Without definitive knowledge of this information, development of mission requirements is hampered. Additionally, even if waste streams were well characterized, other operational and processing needs require clarification (e.g. resource recovery requirements and planetary protection constraints). Therefore, the development of solid waste management (SWM) subsystem requirements for long duration space missions is an inherently uncertain, complex and iterative process.

This paper describes work that has begun at Ames Research Center on development of a heat melt compactor that can be used on near term and future missions. The heat melt compactor can handle wastes with a significant plastic composition and minimize crew interaction. The current solid waste management system employed on the International Space Station (ISS) consists of compaction, storage, and disposal. Wastes such as plastic food packaging and trash are compacted manually and wrapped in duct taped “footballs” by the astronauts. Much of the waste is simply loaded into the empty Russian Progress spacecraft that is used to bring supplies to ISS. The progress spacecraft and its contents are intentionally burned up in the earth's atmosphere during reentry. This manual method of trash management on ISS is a wasteful use of crew time and does not transition well to far term missions.

Of the many competing technologies for resource recovery from solid wastes for long duration manned missions such as a lunar or Mars base, incineration technology is one of the most promising and certainly the most well developed in a terrestrial sense. Various factors are involved in the design of an optimum fluidized bed incinerator for inedible biomass. The factors include variability of moisture in the biomass, the ash content, and the amount of fuel nitrogen in the biomass. The crop mixture in the waste will vary; consequently the nature of the waste, the nitrogen content, and the biomass heating values will vary as well. Variation in feed will result in variation in the amount of contaminants such as nitrogen oxides that are produced in the combustion part of the incinerator. The incinerator must be robust enough to handle this variability. Research at NASA Ames Research Center using the fluidized bed incinerator has yielded valuable data on system parameters and variables.

Of the many competing technologies for resource recovery from solid wastes for long duration manned missions such as a lunar or Mars base, incineration technology is one of the most promising and certainly the most well developed in a terrestrial sense. An incinerator was used to recover and recycle part of the waste produced during the Early Human Testing Initiative Phase 3 (EHTI 3) at Johnson Space Center. The fluidized bed incinerator developed for the EHTI testing was a joint initiative between Ames Research Center, University of Utah and Johnson Space Center. Though in no way an optimized system at that time, the fluidized bed combustor fulfilled the basic requirements of a resource recovery system. Valuable data was generated and problem areas, technology development issues and future research directions were identified during the EHTI testing.

This paper provides an overview of the IMMWPS Integrated Ground Test Program, completed at the NASA Johnson Space Center (JSC) during October and November 2001. The JSC Crew and Thermal Systems Division (CTSD) has developed the IMMWPS orbital flight experiment to test the feasibility of a microbe-based water purifier for use in zero-gravity conditions. The IMMWPS design utilizes a Microbial Processor Assembly (MPA) inoculated with facultative anaerobes to convert organic contaminants in wastewater to carbon dioxide and biomass. The primary purpose of the ground test program was to verify functional operations and procedures. A secondary objective was to provide initial ground data for later comparison to on-orbit performance. This paper provides a description of the overall test program, including the test article hardware and the test sequence performed to simulate the anticipated space flight test program. In addition, a summary of significant results from the testing is provided.

A closed-loop air revitalization system requires continuous removal of CO2 from the breathing air and an oxygen recovery system to recover oxygen from the waste CO2. Production of oxygen from CO2 is typically achieved by reacting CO2 with hydrogen in a reduction unit such as a Sabatier reactor. The air revitalization system of International Space Station (ISS) currently operates on an open loop mode where CO2 is being vented into the space vacuum due to lack of a Sabatier Reactor. A compressor and a storage device are required to interface the Carbon Dioxide Removal Assembly (CDRA) and the Sabatier reactor. This compressor must acquire the low-pressure CO2 from CDRA and provide it at a high enough pressure to the Sabatier reactor. The compressor should ensure independent operations of CDRA and Sabatier reactor at all times, even when their operating schedules are not synchronized.

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.

Solid Waste Management (SWM) systems of current and previous space flight missions have employed relatively uncomplicated methods of waste collection, storage and return to Earth. NASA's long-term objectives, however, will likely include human-rated missions that are longer in both duration and distance, with little to no opportunity for re-supply. Such missions will likely exert increased demands upon all sub-systems, particularly the SWM system. In order to provide guidance to SWM Research and Technology Development (R&TD) efforts and overall system development, the establishment of appropriate SWM system requirements is necessary. Because future long duration missions are not yet fully defined, thorough mission-specific requirements have not yet been drafted.

Engineers at the Johnson Space Center (JSC) are using innovative strategies to design the TCS for the Bio-regenerative Planetary Life Support Systems Test Complex (BIO-Plex), a regenerative advanced life support system ground test bed. This paper provides a current description of the BIO-Plex TCS design, testing objectives, analyses, descriptions of the TCS test articles expected to be tested in the BIO-Plex, and forward work regarding TCS. The TCS has been divided into some subsystems identified as permanent “infrastructure” for the BIO-Plex and others that are “test articles” that may change from one test to the next. The infrastructure subsystems are the Heating, Ventilation and Air-Conditioning (HVAC), the Crew Chambers Internal Thermal Control Subsystem (CC ITCS), the Biomass Production Chamber Internal Thermal Control Subsystem (BPC ITCS), the Waste Heat Distribution Subsystem (WHDS) and the External Thermal Control Subsystem (ETCS).

Automatic thermal control (ATC) was investigated for implementation into a spacesuit to provide thermal neutrality to the astronaut through a range of activity levels. Two different control concepts were evaluated and compared for their ability to maintain subject thermal comfort. Six test subjects, who were involved in a series of three tests, walked on a treadmill following specific metabolic profiles while wearing the Mark III spacesuit in ambient environmental conditions. Results show that individual subject comfort was effectively provided by both algorithms over a broad range of metabolic activity. ATC appears to be highly effective in providing efficient, “hands-off” thermal regulation requiring minimal instrumentation. Final selection of an algorithm to be implemented in an advanced spacesuit system will require testing in dynamic thermal environments and consideration of technology for advancement in instrumentation and controller performance.

An analysis model has been developed for analyzing/optimizing the integration of a carbon dioxide removal assembly (CDRA), CO2 compressor, accumulator, and Sabatier CO2 reduction assembly. The integrated model can be used in optimizing compressor sizes, compressor operation logic, water generation from Sabatier, utilization of CO2 from crew metabolic output, and utilization of H2 from oxygen generation assembly. Tests to validate CO2 desorption, recovery, and compression had been conducted in 2002-2003 using CDRA/Simulation compressor set-up at NASA Marshall Space Flight Center (MSFC). An analysis of test data has validated CO2 desorption rate profile, CO2 compressor performance, CO2 recovery and CO2 vacuum vent in the CDRA model. Analysis / optimization of the compressor size and the compressor operation logic for an integrated closed air revitalization system is currently being conducted

A concentrated development effort was begun at NASA Johnson Space Center to create an advanced Portable Life Support System (PLSS) packaging concept. Ease of maintenance, technological flexibility, low weight, and minimal volume are targeted in the design of future micro-gravity and planetary PLSS configurations. Three main design concepts emerged from conceptual design techniques and were carried forth into detailed design, then full scale mock-up creation. “Foam”, “Motherboard”, and “LEGO™” packaging design concepts are described in detail. Results of the evaluation process targeted maintenance, robustness, mass properties, and flexibility as key aspects to a new PLSS packaging configuration. The various design tools used to evolve concepts into high fidelity mock ups revealed that no single tool was all encompassing, several combinations were complimentary, the devil is in the details, and, despite efforts, many lessons were learned only after working with hardware.

The On-line Project Information System (OPIS) is a web-based database developed at NASA Ames Research Center (ARC) to improve information transfer and data availability for Exploration Life Support (ELS) projects. The tool enables users to investigate NASA technology development efforts, connect with knowledgeable experts, and to communicate important information. Within OPIS, Principal Investigators (PI's) post technical, administrative, and project participant information for other users to access through browse and search mechanisms. PI's are given technical data reporting requirements in the form of annual report templates, to assure that the information reported satisfies the most critical data needs of various ELS user groups. OPIS fulfills data and functionality needs of key user groups in the ELS Community through data solicitation, centralization, and distribution. The tool also circumvents data loss with ELS participant turnover.

In an effort to define and advance the new discipline of Space Architecture, the AIAA technical subcommittee on Aerospace Architecture organized a Space Architecture Workshop that took place during the World Space Congress 2002 in Houston, Texas. One of the results of this workshop is a “Mission Statement for Space Architecture” that addresses the following core issues in a concise manner: definition, motivation, utility, required knowledge, and related disciplines. The workshop also addressed the typology and principles of space architecture, as well as basic philosophical guidelines for practitioners of this discipline. The mission statement, which was unanimously adopted by the workshop participants, reads as follows ([1], [2], [3]): “Space Architecture is the theory and practice of designing and building inhabited environments in outer space, responding to the deep human drive to explore and occupy new places.