EVA metabolic capacity required for LEP life support system
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Bottomley, T. A.↗
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Results for “Life support systems”
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Guiding the development of a controlled ecological life support system
The workshop is reported which was held to establish guidelines for future development of ecological support systems, and to develop a group of researchers who understand the interdisciplinary requirements of the overall program.
Mason, R. M.↗
Fault diagnostic instrumentation design for environmental control and life support systems
As a development phase moves toward flight hardware, the system availability becomes an important design aspect which requires high reliability and maintainability. As part of continous development efforts, a program to evaluate, design, and demonstrate advanced instrumentation fault diagnostics was successfully completed. Fault tolerance designs for reliability and other instrumenation capabilities to increase maintainability were evaluated and studied.
Yang, P. Y.↗
Evaluation of engineered foods for Closed Ecological Life Support System (CELSS)
A system of conversion of locally regenerated raw materials and of resupplied freeze-dried foods and ingredients into acceptable, safe and nutritious engineered foods is proposed. The first phase of the proposed research has the following objectives: (1) evaluation of feasibility of developing acceptable and reliable engineered foods from a limited selection of plants, supplemented by microbially produced nutrients and a minimum of dehydrated nutrient sources (especially those of animal origin); (2) evaluation of research tasks and specifications of research projects to adapt present technology and food science to expected space conditions (in particular, problems arising from unusual gravity conditions, problems of limited size and the isolation of the food production system, and the opportunities of space conditions are considered); (3) development of scenarios of agricultural production of plant and microbial systems, including the specifications of processing wastes to be recycled.
Karel, M.↗
Controlled ecological life support system - biological problems
The general processes and controls associated with two distinct experimental paradigms are examined. Specific areas for research related to biotic production (food production) and biotic decomposition (waste management) are explored. The workshop discussions were directed toward Elemental cycles and the biological factors that affect the transformations of nutrients into food, of food material into waste, and of waste into nutrients were discussed. To focus on biological issues, the discussion assumed that (1) food production would be by biological means (thus excluding chemical synthesis), (2) energy would not be a limiting factor, and (3) engineering capacity for composition and leak rate would be adequate.
Moore, B., III↗
Evaluation of engineering foods for Controlled Ecological Life Support Systems (CELSS)
The feasibility of developing acceptable and reliable engineered foods for use in controlled ecological support systems (CELSS) was evaluated. Food resupply and regeneration are calculated, flow charts of food processes in a multipurpose food pilot plant are presented, and equipment for a multipurpose food pilot plant and potential simplification of processes are discussed. Food-waste treatment and water usage in food processing and preparation are also considered.
Karel, M.↗
The potential role of aerobic biological waste treatment in regenerative life support systems
The purpose of the paper is to make a preliminary assessment of the feasibility of using aerobic biological waste treatment in closed systems. Issues that are addressed in this paper are: (1) how high a degree of material balance is possible, (2) how much might such a system weigh, and (3) how would system closure and weight be affected if animals were included in the system. A computer model has been developed to calculate for different scenarios the compositions and amounts of the streams entering or leaving the waste treatment system and to estimate the launch weight of such a system. A bench scale apparatus has been built to mimic the proposed waste treatment system; the experiments are used to verify model predictions and to improve model parameter estimations.
Shuler, M. L.↗
Utilization of urea, ammonia, nitrite, and nitrate by crop plants in a Controlled Ecological Life Support System (CELSS)
The utilization of nitrogen compounds by crop plants is studied. The selection of crop varieties for efficient production using urea, ammonia, nitrite, and nitrate, and the assimilation of mixed nitrogen sources by cereal leaves and roots are discussed.
Huffaker, R. C.↗
Generic Waste Management Requirements for a Controlled Ecological Life Support System (CELSS)
Sources of waste, general requirements for plant growth, plant culturing systems, output requirements to match candidate plants, and integration of subsystems are addressed.
Hoshizaki, T.↗
Techniques for the inorganic analysis in a controlled ecological life support system
Sample preparation, instrumental analysis, a direct injection device for IC/ICP interfacing, a hydraulic jet bend impaction device, monodisperse aerosol generator, and low gravity environments are discussed.
Source record↗
Controlled environment life support system: Calcium-related leaf injuries on plants
A calcium related injury in lettuce termed tipburn was the focus of this study. It affects the young developing leaves as they become enclosed during head formation. It is a good model system to study because the injury can be induced with good predictability and lettuce is one of the crops chosen by the CELSS program for concentrated study. Investigations were undertaken to study a number of different procedures, that would have the potential for encouraging movement of calcium into the young developing leaves and to study the time course and pattern of calcium accumulation in developing leaves to provide a basis for developing effective control procedures for this injury.
Tibbitts, T. W.↗
Controlled Ecological Life Support Systems: CELSS 1985 Workshop
Various topics related to closed ecological systems are discussed. Space habitats, vegetative growth, photosynthesis, recycling, culture techniques, waste utilization bioreactors and controlled atmospheres on space stations are among the topics covered.
Macelroy, R. D.↗
Controlled environment life support system: Growth studies with potatoes
Results of experiments conducted to maximize the productivity of potatoes grown under controlled environmental conditions are discussed. A variety of parameters is examined which affect potato growth, specifically, photoperiod, light intensity, temperature, nitrogen nutrition, carbon dioxide concentration and culture techniques. These experiments were conducted using five different cultivars, Russet Burbank, Norchip, Superior, Kennebec and Norland. To achieve high productivity, three specific objectives were explored: (1) to develop effective cultural procedures, (2) to determine the most effective photoperiod and (3) to develop a mist culture system. It is felt that the productivity obtained in this study is below the maximum that can be obtained. High irradiance levels coupled with tuber-promoting conditions such as cooler temperatures, increased CO2 levels and lowered nitrogen concentrations should allow increases in tuber production. Tuberization appears to be accelerated by short daylengths although final yields are not increased. Mist culture techniques have not yet produced fully developed tubers. The use of supporting media and alteration of the nitrogen content of the mist solution are being explored as a way to allow tubers to develop to maturity.
Tibbitts, T. W.↗
Controlled environment life support system: Calcium-related leaf injuries on plants
Calcium related injuries to plants grown in controlled environments under conditions which maximize plant growth rates are described. Procedures to encourage movement of calcium into developing leaves of lettuce plants were investigated. The time course and pattern of calcium accumulation was determined to develop effective control procedures for this injury, termed tipburn. Procedures investigated were: (1) increasing the relative humidity to saturation during the dark period and altering root temperatures, (2) maximizing water stress during light and minimizing water stress during dark periods, (3) shortening the light-dark cycle lengths in combination with elevated moisture levels during the dark cycles, (4) reducing nutrient concentrations and (5) vibrating the plants. Saturated humidities at night increased the rate of growth and the large fluctuation in plant water potential encouraged calcium movement to the young leaves and delayed tipburn. Root temperature regulation between 15 and 26 C was not effective in preventing tipburn. Attempts to modulate water stress produced little variation, but no difference in tipburn development. Variations in light-dark cycle lengths also had no effect on calcium concentrations within developing leaves and no variation in tipburn development. Low concentrations of nutrient solution delayed tipburn, presumably because of greater calcium transport in the low concentration plants. Shaking of the plants did not prevent tipburn, but did delay it slightly.
Tibbitts, T. W.↗
Growth of plant tissue cultures in simulated lunar soil: Implications for a lunar base Controlled Ecological Life Support System (CELSS)
Experiments to determine whether plant tissue cultures can be grown in the presence of simulated lunar soil (SLS) and the effect of simulated lunar soil on the growth and morphogenesis of such cultures, as well as the effect upon the germination of seeds and the development of seedlings were carried out . Preliminary results on seed germination and seedling growth of rice and calli growth of winged bean and soybean indicate that there is no toxicity or inhibition caused by SLS. SLS can be used as a support medium with supplements of certain major and micro elements.
Venketeswaran, S.↗
Utilization of potatoes in bioregenerative life support systems
Data on the tuberization, harvest index, and morphology of 2 cvs of white potato (Solanum tuberosum L.) grown at 12, 16, 20, 24 and 28 C, 250, 400 and 550 micromol/s/m photosynthetic photon flux (PPF), 350, 1000 and 1600 microliter 1 sup -1 CO2 is presented. A productivity of 21.9 g/m day sup -1 of edible tubers from a solid stand of potatoes grown for 15 weeks with continuous irradiation at 400 micromol/s/m, 16 C and 1000 microliter 1 sup -1 CO2 was obtained. This equates to an area of 34.3 sq m being required to provide 2800 kcal of potatoes per day for a human diet. Separated plants receiving side lighting have produced 32.8 g/m day sup -1 which equates to an area of 23.6 sq m to provide 2800 kcal. Studies with side lighting indicate that productivities in this range should be realized from potatoes. Glycoalkaloid levels in tubers of controlled environment grown plants are within the range of levels found in tubers of field grown plants. The use and limitation of recirculating solution cultures for potato growth is discussed.
Tibbitts, T. W.↗
The environmental control and life support system for a lunar base - What drives its design
It is noted that no single ECLSS is uniquely applicable to a mission of given crew size and duration; all mission parameters, together with details of other systems, must accordingly be factored into the lunar base ECLSS design process that is presently discussed. Experience to date with ECLSS design tasks indicates that mission planners and systems engineers should refrain from emphasizing the 'closed loop' aspects of such systems, since even the best regenerative processes will involve expendable materials that must be resupplied; resupply logistics will accordingly constitute a considerable effort of lunar base operation. Technology development status for processes and subsystems is identified as a major ECLSS design driver.
Hypes, Warren D.↗
Model description document for a computer program for the emulation/simulation of a space station environmental control and life support system (ESCM)
Emulation/Simulation Computer Model (ESCM) computes the transient performance of a Space Station air revitalization subsystem with carbon dioxide removal provided by a solid amine water desorbed subsystem called SAWD. This manual describes the mathematical modeling and equations used in the ESCM. For the system as a whole and for each individual component, the fundamental physical and chemical laws which govern their operations are presented. Assumptions are stated, and when necessary, data is presented to support empirically developed relationships.
Yanosy, James L.↗