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The design and evaluation of a Vacuum-Swing Adsorption (VSA) system to remove metabolic water and metabolic carbon dioxide from a spacecraft atmosphere is presented. The approach for Orion and Altair is a VSA system that removes not only 100 percent of the metabolic CO2 from the atmosphere, but also 100% of the metabolic water as well, a technology approach that has not been used in previous spacecraft life support systems. The design and development of an Orion Crew Exploration Vehicle Sorbent Based Atmosphere Revitalization system, including test articles, a facility test stand, and full-scale testing in late 2008 and early 2009 is discussed.

In preparation for the contract award of the Crew Exploration Vehicle (CEV), the National Aeronautics and Space Administration (NASA) produced two design reference missions for the vehicle. The design references used teams of engineers across the agency to come up with two configurations. This process helped NASA understand the conflicts and limitations in the CEV design, and investigate options to solve them.

Spacecraft hardware trade studies compare options primarily on mass while considering impacts to cost, risk, and schedule. Historically, other factors have been considered in these studies, such as reliability, technology readiness level (TRL), volume and crew time. In most cases, past trades compared two or more technologies across functional and TRL boundaries, which is an uneven comparison of the technologies. For example, low TRL technologies with low mass were traded directly against flight-proven hardware without consideration for requirements and the derived architecture. To provide for even comparisons of spacecraft hardware, trades need to consider functionality, mission constraints, integer vs. real number of flight hardware units, and mass growth allowances by TRL.

The design of a vacuum-swing adsorption process to remove metabolic water, metabolic carbon dioxide, and metabolic and equipment generated trace contaminant gases from the Orion Crew Exploration Vehicle (CEV) atmosphere is presented. For Orion, the approach is taken that all metabolic water must be removed by the Sorbent-Based Atmosphere Revitalization System (SBAR), a technology approach that has not been used in previous spacecraft life support systems. Design and development of a prototype SBAR, a facility test stand, and subsequent testing of the SBAR in late 2006 and early 2007 is discussed.

The paper provides a summary of current work accomplished under technical task agreement (TTA) by the Marshall Space Flight Center (MSFC) regarding the Environmental Control and Life Support System (ECLSS) as well as future planning activities in support of the International Space Station(ISS).Current activities computer model development, component design and development, subsystem/integrated system testing, life testing, and government furnished equipment delivered to the ISS program. A long range plan for the MSFC ECLSS test facility is described whereby the current facility would be upgraded to support integrated station ECLSS operations. ECLSS technology development efforts proposed to be performed under the Advanced Engineering Technology Development (AETD) program are also discussed.

Advanced life support flight experiments have been conceptualized for the International Space Station (ISS). Two of the experiments, a high pressure oxygen generator and a carbon dioxide reduction subsystem, offer high payback potential to the ISS program. This paper documents the cost-benefit analyses for these two experiments.

A test has been completed at NASA's Marshall Space Flight Center (MSFC) to evaluate the Water Recovery and Management (WRM) system and Waste Management (WM) urinal design for the United States On-Orbit Segment (USOS) of the International Space Station (ISS). Potable and urine reclamation processors were integrated with waste water generation equipment and successfully operated for a total of 128 days in recipient mode configuration to evaluate the accumulation of contaminants in the water system and to assess the performance of various modifications to the WRM and WM hardware. No accumulation of contaminants were detected in the product water over the course of the recipient mode test. An additional 18 days were conducted in donor mode to assess the ability of the system to removal viral contaminants, to monitor the breakthrough of organic contaminants through the multifiltration bed, and for resolving anomalies that occurred during the test.

A two year test program has been initiated to evaluate the effects of extended duration operation on a solid polymer electrolyte Oxygen Generator Assembly (OGA); in particular the cell stack and membrane phase separators. As part of this test program, the OGA was integrated into the Marshall Space Flight Center (MSFC) Water Recovery Test (WRT) Stage 10, a six month test, to use reclaimed water directly from the water processor product water storage tanks. This paper will document results encountered and evaluated thus far in the life testing program.

The design of a Vacuum-Swing Adsorption (VSA) system to remove metabolic water and metabolic carbon dioxide from the Orion Crew Exploration Vehicle (CEV) atmosphere is presented. The approach for Orion is a VSA system that removes not only 100 percent of the metabolic CO2 from the atmosphere, but also 100% of the metabolic water as well, a technology approach that has not been used in previous spacecraft life support systems. The design and development of the Sorbent Based Atmosphere Regeneration (SBAR) system, including test articles, a facility test stand, and full-scale testing in late 2007 and early 2008 is discussed.

NASA's Constellation Program, which includes the mission objectives of establishing a permanently-manned lunar Outpost, and the exploration of Mars, poses new and unique challenges for human life support systems that will require solutions beyond the Shuttle and International Space Station state of the art systems. In particular, the requirement to support crews for extended durations at the lunar outpost with limited resource resupply capability will require closed-loop regenerative life support systems with minimal expendables. Planetary environmental conditions such as lunar dust and extreme temperatures, as well as the capability to support frequent and extended-duration Extra-vehicular Activity's (EVA's) will be particularly challenging.

Long duration human space missions, as planned in the Vision for Space Exploration, will not be possible without applying unprecedented levels of automation to support the human endeavors. The automated and robotic systems must carry the load of routine “housekeeping” for the new generation of explorers, as well as assist their exploration science and engineering work with new precision. Fortunately, the state of automated and robotic systems is sophisticated and sturdy enough to do this work — but the systems themselves have never been human-rated as all other NASA physical systems used in human space flight have. Our intent in this paper is to provide perspective on requirements and architecture for the interfaces and interactions between human beings and the astonishing array of automated systems; and the approach we believe necessary to create human-rated systems and implement them in the space program.

An austere fiscal environment in the aerospace community creates pressure to reduce program costs, often minimizing or even deleting human interface requirements from the design process. With the assumption that the flight crew can recover, in real time, from a poorly human factored space vehicle design, the classical crew interface requirements have either been not included in the design or not properly funded, even though they are carried as requirements. Cost cuts have also affected the quality of retained human factors engineering personnel. Planning is ongoing to correct these issues. Herein are techniques for ensuring that human interface requirements are integrated with flight design from proposal through verification and launch activation.

The International Space Station (ISS) modules Nodes 2 and 3 are progressing through the design phase into integration, test, and verification. This paper gives a status of the Nodes 2 and 3 Environmental Control and Life Support System (ECLSS) design progress since 1999 (ICES paper 1999-01-2146). The Node 2 Design Review 2 was completed in March 2001. Node 2 is currently in the hardware integration/test phase at Alenia Spazio. The ECLSS for Node 2 includes inter- and intramodule ventilation, temperature and humidity control, distribution of atmosphere samples, low pressure and recharge oxygen and nitrogen, fuel cell and wastewater, and fire detection and suppression. Changes/challenges since 1999 have included the addition of a low temperature loop coolant bypass around the Common Cabin Air Assembly condensing heat exchanger and resolution of common hardware and verification issues. The current status of hardware integration and testing is also discussed.

A three-year program to develop a Direct Drive Hall Effect Thruster (D2HET) system began 15 months ago as part of the NASA Advanced Cross-Enterprise Technology Development initiative. The system is expected to reduce significantly the power processing, complexity, weight, and cost over conventional low-voltage systems. The D2HET will employ solar arrays that operate at voltages greater than 300V, and will be an enabling technology for affordable planetary exploration. It will also be a stepping-stone in the production of the next generation of power systems for Earth orbiting satellites. This paper provides a general overview of the program and reports the first year's findings from both theoretical and experimental components of the program.

The design of a vacuum-swing adsorption process to remove metabolic water, metabolic carbon dioxide, and metabolic and equipment generated trace contaminant gases from the crew exploration vehicle (CEV) atmosphere is presented. For the CEV, the sorbent-based atmosphere revitalization (SBAR) system must remove all metabolic water, a technology approach that has not been used in previous spacecraft life support systems. Design and development of a prototype SBAR, a full scale and subscale facility test stand, and other aspects of the SBAR development program is discussed.

NASA - Marshall Space Flight Center has implemented fault injection into an electrical power system breadboard to study the reactions of the various control elements of this breadboard. Among the elements studied are the Remote Power Controllers (RPC), the algorithms in the control computers and the artificially intelligent control programs resident in this breadboard. To this end, a study of electrical power system faults was performed to yield a list of the most common power system faults. The results of this study were applied to a multichannel high voltage dc spacecraft power system called the Large Autonomous Spacecraft Electrical Power System Breadboard (LASEPS). The results of the study into the most common electrical power system faults was presented in two papers at this conference during the last two years;* the remainder of the results of this study are to be presented in this paper.

NASA - Marshall Space Flight Center is creating a large high voltage electrical power system testbed called LASEPS. This testbed is being developed to simulate an end-to-end power system from power generation and source to loads. When the system is completed it will have several power configurations, which will include several battery configurations. These configurations are: two 120 V batteries, one or two 150 V batteries, and one 250 to 270 V battery. This breadboard encompasses varying levels of autonomy from remote power converters to conventional software control to expert system control of the power system elements. In this paper, the construction and provisions of this breadboard will be discussed.

A series of tests has been conducted at the NASA Marshall Space Flight Center (MSFC) to evaluate the performance of the Space Station Freedom (SSF) water recovery system. Potable and urine reclamation processors were integrated with waste water generation equipment and successfully operated for a total of 144 days. This testing marked the first occasion in which the waste feed sources for previous potable and hygiene loops were combined into a single loop and processed to potable water quality. Reclaimed potable water from the combined waste waters routinely met the SSF water quality specifications. In the last stage of this testing, data was obtained that indicated that the Water Processor (WP) presterilizer may not be required to meet the potable water quality specification.

A series of tests has been conducted at the NASA Marshall Space Flight Center (MSFC) to evaluate the performance of a Space Station Freedom (SSF) pre-development water recovery system. Potable, hygiene, and urine reclamation subsystems were integrated with end-use equipment items and successfully operated for a total of 35 days, including 23 days in closed-loop mode with man-in-the-loop. Although several significant subsystem physical anomalies were encountered, reclaimed potable and hygiene water routinely met current SSF water quality specifications. This paper summarizes the test objectives, system design, test activities/protocols, significant results/anomalies, and major lessons learned.

A primary concern in creating a water reclamation system for long-duration manned space flight is the control of microbial contamination which can jeopardize water quality, compromise human health, and degrade constituent materials of the system. The microbial ecology facility in the Analytical and Physical Chemistry Branch of the Materials and Processes Laboratory at NASA's Marshall Space Flight Center (MSFC) is addressing this concern by means of experiments investigating the interaction of bacterial species in the development of a biofilm and their response to the introduction of additional species or to disinfection. Both static and recycling water systems are used. In static experiments, varied sequence and timing of species introduction in binary bacterial biofilms on 316L stainless steel elucidate the mechanisms involved in biofilm formation.