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This paper describes the results of ground testing of a scroll pump with a potential of being a substitute for the current vacuum pump of the Vapor Phase Catalytic Ammonia Reduction (VPCAR). Assessments of the pressure-time, pump-down time, pump power and the pump noise were made for three configurations of the pump the first of which was without the gas ballast, the second with the gas ballast installed but not operating and the third with the gas ballast operating. The tested scroll pump exhibited optimum characteristics given its mass and power requirements. The pump down time required to reach a pressure of 50 Torr ranged from 60 minutes without the ballast to about 120 minutes with the gas ballast operational. The noise emission and the pump power were assessed in this paper as well.

Handling and processing human feces in space habitats is a major concern and needs to be addressed for the Crew Exploration Vehicle (CEV) as well as for future exploration activities. In order to ensure crew health and safety, feces should either be isolated in a dried form to prevent microbial activity, or be processed to yield a non-biohazardous product using a reliable technology. During laboratory testing of new feces processing technologies, use of “real” feces can impede progress due to practical issues such as safety and handling thereby limiting experimental investigations. The availability of a non-hazardous simulant or analogue of feces can overcome this limitation. Use of a simulant can speed up research and ensure a safe laboratory environment. At Ames Research Center, we have undertaken the task of developing human fecal simulants. In field investigations, human feces show wide variations in their chemical/physical composition.

The white rat, Rattus norvegicus has been used extensively in microgravity flights. Initial NASA flight experiments with rats supported the Shuttle Student Involvement Program (SSIP). Hardware to house the rats was called the Animal Enclosure Module (AEM). The AEM for the SSIP, fit into a middeck locker. Potatoes provided water; food bars, glued on the walls, provided nourishment. Waste was absorbed and odor and microbial growth controlled by sandwiched phosphoric acid treated charcoal and filter materials utilizing much of the technology employed in the Rodent Research Animal Holding Facility, a Spacelab piece of equipment. The SSIP AEM potato “watering” system succumbed to mold and had to be replaced by real water contained within plasma bags. A metal enclosure housed the plasma bags between two heavy springs which forced water through animal activated lixits.

Management of human feces and wastes is a major challenge in space vehicles due to the potential biohazards and malodorous compounds emanating during collection and storage of feces and wastes. To facilitate safe, yet realistic human waste management research, we have previously developed human fecal simulants for research activities. The odoriferous compounds in feces and wastes reduce the quality of life for astronauts, can reduce performance, and can even cause health problems. The major odoriferous compounds of concern belong to four groups of chemicals, volatile fatty acids, volatile sulfurous compounds, nitrogenous compounds and phenols. This paper attempts to review the problem of odor detection and odor control with advanced technology. There has been considerable progress in odor detection and control in the animal industry and in the dental profession.

A Microwave Enhanced Freeze Drying Solid Waste (MEFDSW) processor was delivered to NASA-Ames Research Center by Umpqua Company having been funded through a Small Business Innovative Research Phase II program. The prototype hardware was tested for its performance characteristics and for its functionality with the primary focus being the removal of water from solid wastes. Water removal from wastes enables safe storage of wastes, prevents microbes from growing and propagating using the waste as a substrate and has potential for recovery and reuse of the water. Other objectives included measurements of the power usage and a preliminary estimate of the Equivalent System Mass (ESM) value. These values will be used for comparison with other candidate water removal technologies currently in development.

The demanding performance requirements of advanced turbine-powered tactical aircraft have made it important to understand and accurately evaluate the propulsion system/airframe interactions. The turbine engine multi-mission propulsion simulator offers the potential for accurate evaluation of these interactions by permitting the simultaneous simulation of inlet/airframe/nozzle flowfields on a single wind tunnel model. Extensive simulator usage is expected during developmental testing of supersonic V/STOL and in-flight thrust vectoring configurations, which have significant flowfield interactions. The simulator has been successfully demonstrated in a wind tunnel test program, and is currently undergoing development to a more compact version.

Spacelab-J was an international Spacelab mission with numerous innovative Japanese and American materials and life science experiments. Two of the Spacelab-J experiments were designed over a period of more than a decade by a team from NASA-Ames Research Center. The Frog Embryology Experiment investigated and is helping to resolve a century-long quandary on the effects of gravity on amphibian development. The Autogenic Feedback Training Experiment, flown on Spacelab-J as part of a multi-mission investigation, studied the effects of Autogenic Feedback Therapy on limiting the effects of Space Motion Sickness on astronauts. Both experiments employed the use of a wide variety of specially designed hardware to achieve the experiment objectives.

Nitrogen use efficiency in hydroponic plant growth chambers is reduced by microbial denitrification. A computer-controlled bioreactor system was developed to investigate methods for controlling denitrification in hydroponic plant growth chambers envisioned for use on long duration space missions. Through regulation of O2 and NO3- levels in the bioreactor, the rate of denitrification of pure cultures was controlled. This control strategy may be used to favor plant nitrate uptake in the presence of denitrifying bacteria in hydroponic systems. Reducing denitrification provides advantages to advanced life support (ALS) systems by improving crop nitrogen use efficiency, reducing fixed-nitrogen demand, and reducing gaseous wastes (N2O and N2).

The effects of acoustic levels in manned space vehicles was not thoroughly appreciated until the STS 40 mission, Spacelab Life Sciences 1 (June, 1991). Previous to that mission, waivers were submitted and equipment operated without overwhelming effect on ongoing flight activities. The factors of multiple pieces of noise producing equipment operating simultaneously, operating in the vicinity of crew sleep stations, and operating for this long of a mission (10 days) became relevant in crew tolerance, fatigue, communication, and permanent shifts in hearing thresholds. Because this was a life sciences mission, accurate instrument measurements were obtained of acoustic levels in the middeck, flight deck and spacelab during flight and physiological measurements were obtained from the crew members during all phases of the mission. Due to the STS 40 results, a Spacelab/Payloads Acoustics Working Group (SPAWG) was formed post flight to address acceptable acoustic limits.