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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 433 records · Page 24
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

A method of evaluating efficiency during space-suited work in a neutral buoyancy environment

The purpose was to investigate efficiency as related to the work transmission and the metabolic cost of various extravehicular activity (EVA) tasks during simulated microgravity (whole body water immersion) using three space suits. Two new prototype space station suits, AX-5 and MKIII, are pressurized at 57.2 kPa and were tested concurrently with the operationally used 29.6 kPa shuttle suit. Four male astronauts were asked to perform a fatigue trial on four upper extremity exercises during which metabolic rate and work output were measured and efficiency was calculated in each suit. The activities were selected to simulate actual EVA tasks. The test article was an underwater dynamometry system to which the astronauts were secured by foot restraints. All metabolic data was acquired, calculated, and stored using a computerized indirect calorimetry system connected to the suit ventilation/gas supply control console. During the efficiency testing, steady state metabolic rate could be evaluated as well as work transmitted to the dynamometer. Mechanical efficiency could then be calculated for each astronaut in each suit performing each movement.

Greenisen, Michael C.↗
NASA NTRS1994

Research and technology, 1993

Selected research and technology activities at Ames Research Center, including the Moffett Field site and the Dryden Flight Research Facility, are summarized. These activities exemplify the center's varied and productive research efforts for 1993. This year's report presents some of the challenging work recently accomplished in the areas of aerospace systems, flight operations and research, aerophysics, and space research.

Source record↗
NASA NTRS2004

Remote Sensing Assessment of Lunar Resources: We Know Where to Go to Find What We Need

The utilization of space resources is necessary to not only foster the growth of human activities in space, but is essential to the President s vision of a "sustained and affordable human and robotic program to explore the solar system and beyond." The distribution of resources will shape planning permanent settlements by affecting decisions about where to locate a settlement. Mapping the location of such resources, however, is not the limiting factor in selecting a site for a lunar base. It is indecision about which resources to use that leaves the location uncertain. A wealth of remotely sensed data exists that can be used to identify targets for future detailed exploration. Thus, the future of space resource utilization pre-dominantly rests upon developing a strategy for resource exploration and efficient methods of extraction.

Gillis, J. J.↗
NASA NTRS2014

Innate Immune Responses of Drosophila Melanogaster are Altered by Spaceflight

Alterations and impairment of immune responses in humans present a health risk for space exploration missions. The molecular mechanisms under pinning innate immune defense can be confounded by the complexity of the acquired immune system of humans. Drosophila (fruit fly) innate immunity is simpler, and shares many similarities with human innate immunity at the level of molecular and genetic pathways. The goals of this study were to elucidate fundamental immune processes in Drosophila affected by spaceflight and to measure host-pathogen responses post-flight. Five containers, each containing ten female and five male fruit flies, were housed and bred on the space shuttle (average orbit altitude of330.35 km) for 12 days and 18.5 hours. A new generation of flies was reared in microgravity. In larvae, the immune system was examined by analyzing plasmatocyte number and activity in culture. In adults, the induced immune responses were analyzed by bacterial clearance and quantitative real-time polymerase chain reaction (qPCR) of selected genes following infection with E. coli. The RNA levels of relevant immune pathway genes were determined in both larvae and adults by microarray analysis. The ability of larval plasmatocytes to phagocytose E. coli in culture was attenuated following spaceflight, and in parallel, the expression of genes involved in cell maturation was down regulated. In addition, the level of constitutive expression of pattern recognition receptors and opsonins that specifically recognize bacteria, and of lysozymes, antimicrobial peptide (AMP) pathway and immune stress genes, hallmarks of humoral immunity, were also reduced in larvae. In adults, the efficiency of bacterial clearance measured in vivo following a systemic infection with E. coli post-flight, remained robust. We show that spaceflight altered both cellular and humoral immune responses in Drosophila and that the disruption occurs at multiple interacting pathways.

Marcu, Oana↗
NASA NTRS2018

Low Temperature Characterization of Mechanical Isolators for Cryocoolers

For spacecraft applications requiring active refrigeration, exported vibrations from a cryocooler can be a concern. One approach to minimizing the vibrations transmitted from cryocoolers to the spacecraft is to mount them on mechanical isolators. Many commercial off-theshelf (COTS) mechanical isolators exist and have been characterized at room temperature for ground applications. However, the space environment presents challenges that complicate the selection process. Mechanical isolators in space must be made of materials that can withstand harsh radiation environments. Future instruments, such as the Mapping Imaging Spectrometer for Europa (MISE) on the Europa Clipper mission, are considering operating cryocoolers with low heat rejection temperatures and mounting them on mechanical isolators. However, the performance of many simple, traditional mechanical isolators at low temperatures is unknown. This paper describes the testing and results of various mechanical isolators able to withstand harsh radiation between 200 K and 300 K. The transmissibility of wire rope type isolators showed very little temperature dependence up to ~500 Hz. On the other hand, the transmissibility of silicone gel was strongly dependent on temperature as the material had an abrupt change in stiffness near its solid-solid phase change. Custom titanium flexures showed the most promise with a maximum transmissibility of 0.04 above 500 Hz and no expected temperature dependence.

Rodriguez, J.I.↗
NASA NTRS2020

2020 IEEE Paper on Psyche margin management, Draft

In January 2017, the mission concept Psyche: Journey to a Metal World was one of two concepts selected by NASA for implementation as part of the 14th Discovery mission competition. Over the course of the past year, the Psyche team has actively worked to refine and mature the technical design, culminating in a successful completion of the Project Preliminary Design review and approval to proceed to Phase C in mid-2019. Psyche is a deep space mission utilizing solar electric propulsion (SEP), consisting of SPT-140 Hall thrusters which have been successfully employed on multiple commercial spacecraft. When launched, Psyche will carry over 1000 kg of Xenon, and will represent the farthest usage of electric propulsion usage from the Sun – a distance of over 3.3 AU. The use of solar electric propulsion in deep space has resulted in challenges unique to other missions. Spacecraft designs typically balance margins across two main elements – mass and power – that are independent of one another. Utilizing a low thrust trajectory through the application of electric propulsion introduces more elements - namely flight time, missed thrust percentage and thruster duty cycle. Moreover, these elements become connected, presenting additional relationships that must be considered. This paper will present an overview of the margin management process for Psyche, and how it has evolved from the early proposal stage to its current state. It will discuss the elements that are margined, their relationship with one another, and key uncertainties that must be addressed. It discusses challenges and mitigations obtained during the refinement of the Psyche project, culminating in a new margin strategy that enables optimization across many of the system elements, and will serve as a template for future deep space SEP missions.

Hart, William↗
NASA NTRSDate not supplied

Communication and Social Science in the Satellite Needs Working Group (SNWG) Assessment

Every two years, NASA conducts an in-depth assessment of the satellite Earth observation data needs of U.S. federal civilian agencies submitted through the Satellite Needs Working Group (SNWG) survey. The SNWG assessment occurs at the nexus of science and people: in the 2022 assessment, over 100 scientists across NASA, NOAA, and USGS were organized to interview over 165 end users at 29 agencies about their unique satellite needs, brainstorm a range of solutions to meet those needs, and communicate back to agencies about resources available for meeting their needs. The innovative approaches to communication, organization, and team make-up that will be described in this talk are vital to the success of the SNWG assessment. As the first major step in evaluating a satellite need, the tri-agency assessment team interviews the agency SMEs who submitted the survey to understand how satellite data could help inform their decision-making process or enable them to fulfill their key responsibilities. In preparation, NASA utilizes social scientists to provide training to all assessment participants on how to hold a discovery-centered interview, including starting with a purpose, creating a welcoming space, exploring all aspects and edges of the need, and brainstorming possible solutions to meet the need. After the interviews, assessment participants propose and review solutions across all thematic areas, seeking those that will help multiple agencies. During the selection process, agencies expected to benefit from a new solution have an opportunity to provide feedback on the proposed activity and are invited to co-design the solution with NASA, should it be implemented. The organization of needs and solutions takes place in Asana, a workflow management tool adapted for the SNWG assessment, and the Report Generation Tool (RGT) enables assessment teams to collaboratively write reports that are returned to each agency with information on current and upcoming resources that help meet their needs.

Katrina Virts↗
NASA NTRS2019

Small Satellites for NASA Earth Science

NASA’s Earth Science Division (ESD) seeks to develop a scientific understanding of Earth and its response to natural and human-induced changes. Earth is a system comprised of diverse components interacting in complex ways. Understanding Earth’s atmosphere, surface and interior, oceans and surface water, ice and snow, and life as a single connected system is necessary in order to improve our predictions of climate, weather, and natural hazards. The ESD’s Flight Program consists of a coordinated series of satellite and airborne systems providing long and short-term, global and regional observations. In addition, the Flight Program provides infrastructure for operating these missions, processing their scientific data, and distributing them on a free and open basis to researchers, operational users, and the public. The Flight Program currently has 24 operating Earth observing space missions and instruments. There are 18 more missions and instruments planned for launch over the next five years. These comprise missions recommended by the National Academies 2017 Earth Science Decadal Survey, missions and selected instruments to ensure availability of key climate data sets, operational missions to sustain the land imaging provided by the Landsat system, and small-sized competitively selected orbital and instrument missions of opportunity belonging to the Earth Venture (EV) program. The Earth Science Decadal Survey, released in early 2018, recommended four new Flight Program elements in addition to the above activities that comprise the Program of Record (POR). Small satellites (~500 kg or less) are essential components of these activities. Presently, there is an increasing use of micro and nanosatellites (or CubeSats) in constellations to support NASA ESD’s scientific objectives. These include the Cyclone Global Navigation Satellite System (CYGNSS) for observing tropical cyclone intensification and genesis factors, the Timed-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS) mission, and the Polar Radiant Energy in the Far InfraRed Experiment (PREFIRE) CubeSat mission. ESD small satellite initiatives like the Small Satellite Constellation Data Buy and Venture Class Launch Services (VCLS) are also underway. The Earth Science Technology Office’s (ESTO) In-Space Validation of Earth Science Technologies (InVEST) and the Venture Technology program elements have launched seven 3U and 6U CubeSat missions to validate advanced instruments and related technologies. An equivalent number of InVEST and other technology demonstration CubeSats are being prepared for launch in the next year. An overview of plans and current status including topics related to small satellite enabling activities will be presented.

Neeck, Steven P.↗
NASA NTRS2005

STS-107 Microgravity Environment Summary Report

This summary report presents the results of the processed acceleration data measured aboard the Columbia orbiter during the STS-107 microgravity mission from January 16 to February 1, 2003. Two accelerometer systems were used to measure the acceleration levels due to vehicle and science operations activities that took place during the 16-day mission. Due to lack of precise timeline information regarding some payload's operations, not all of the activities were analyzed for this report. However, a general characterization of the microgravity environment of the Columbia Space Shuttle during the 16-day mission is presented followed by a more specific characterization of the environment for some designated payloads during their operations. Some specific quasi-steady and vibratory microgravity environment characterization analyses were performed for the following payloads: Structure of Flame Balls at Low Lewis-number-2, Laminar Soot Processes-2, Mechanics of Granular Materials-3 and Water Mist Fire-Suppression Experiment. The Physical Science Division of the National Aeronautics and Space Administration sponsors the Orbital Acceleration Research Experiment and the Space Acceleration Measurement System for Free Flyer to support microgravity science experiments, which require microgravity acceleration measurements. On January 16, 2003, both the Orbital Acceleration Research Experiment and the Space Acceleration Measurement System for Free Flyer accelerometer systems were launched on the Columbia Space Transportation System-107 from the Kennedy Space Center. The Orbital Acceleration Research Experiment supported science experiments requiring quasi-steady acceleration measurements, while the Space Acceleration Measurement System for Free Flyer unit supported experiments requiring vibratory acceleration measurement. The Columbia reduced gravity environment analysis presented in this report uses acceleration data collected by these two sets of accelerometer systems: The Orbital Acceleration Research Experiment is a low frequency sensor, which measures acceleration up to 1 Hz, but the 1 Hz acceleration data is trimmean filtered to yield much lower frequency acceleration data up to 0.01 Hz. This filtered data can be mapped to other locations for characterizing the quasi-steady environment for payloads and the vehicle. The Space Acceleration Measurement System for Free Flyer measures vibratory acceleration in the range of 0.01 to 200 Hz at multiple measurement locations. The vibratory acceleration data measured by this system is used to assess the local vibratory environment for payloads as well as to measure the disturbance causes by the vehicle systems, crew exercise devices and payloads operation disturbances. This summary report presents analysis of selected quasi-steady and vibratory activities measured by these two accelerometers during the Columbia 16-day microgravity mission from January 16 to February 1, 2003.

Jules, Kenol↗
NASA NTRS1975

Space station interior design: Results of the NASA/AIA space station interior national design competition

The results of the NASA/AIA space station interior national design competition held during 1971 are presented in order to make available to those who work in the architectural, engineering, and interior design fields the results of this design activity in which the interiors of several space shuttle size modules were designed for optimal habitability. Each design entry also includes a final configuration of all modules into a complete space station. A brief history of the competition is presented with the competition guidelines and constraints. The first place award entry is presented in detail, and specific features from other selected designs are discussed. This is followed by a discussion of how some of these design features might be applied to terrestrial as well as space situations.

Haines, R. F.↗
NASA NTRS1979

Spacecraft attitude and articulation control systems for future planetary missions

Comparative evaluations of the major types of control systems, such as three-axis-active, spin-stabilized, dual spin, and momentum basis, are performed to determine their applicability for planetary missions in the early 1990s. The key requirements that determine control system selection are science functional, mission orbital, and vehicle configuration characteristics. Five functional groups are given for preliminary control system selection: (1) preliminary survey; (2) detailed remote observation; (3) close scrutiny - deep space; (4) close scrutiny - near sun; (5) sample return. Requirements affecting the selection of attitude/articulation control methods, comparison of the performance capabilities of competing control concepts, criteria for selecting competing methods, comparison of relative complexity, and identification of hardware needs and trends that may affect control system selection are considered.

Mcglinchey, L. F.↗
NASA NTRS1987

A redshift survey of IRAS galaxies

Results are presented from a redshift survey of all 72 galaxies detected by IRAS in Band 3 at flux levels equal to or greater then 2 Jy. The luminosity function at the high luminosity end is proportional to L sup -2, however, a flattening was observed at the low luminosity end indicating that a single power law is not a good description of the entire luminosity function. Only three galaxies in the sample have emission line spectra indicative of AGN's, suggesting that, at least in nearby galaxies, unobscured nuclear activity is not a strong contributor to the far infrared flux. Comparisons between the selected IRAS galaxies and an optically complete sample taken from the CfA redshift survey show that they are more narrowly distributed than those optically selected, in the sence that the IRAS sample includes few galaxies of low absolute blue luminosity. It was also found that the space distributions of the two samples differ: the density enhancement or IRAS galaxies is only approx. 1/3 that of the optically selected galaxies in the core of the Coma cluster.

Smith, Beverly J.↗
NASA NTRS2002

Human Factors Process Task Analysis Liquid Oxygen Pump Acceptance Test Procedure for the Advanced Technology Development Center

A process task analysis effort was undertaken by Dynacs Inc. commencing in June 2002 under contract from NASA YA-D6. Funding was provided through NASA's Ames Research Center (ARC), Code M/HQ, and Industrial Engineering and Safety (IES). The John F. Kennedy Space Center (KSC) Engineering Development Contract (EDC) Task Order was 5SMA768. The scope of the effort was to conduct a Human Factors Process Failure Modes and Effects Analysis (HF PFMEA) of a hazardous activity and provide recommendations to eliminate or reduce the effects of errors caused by human factors. The Liquid Oxygen (LOX) Pump Acceptance Test Procedure (ATP) was selected for this analysis. The HF PFMEA table (see appendix A) provides an analysis of six major categories evaluated for this study. These categories include Personnel Certification, Test Procedure Format, Test Procedure Safety Controls, Test Article Data, Instrumentation, and Voice Communication. For each specific requirement listed in appendix A, the following topics were addressed: Requirement, Potential Human Error, Performance-Shaping Factors, Potential Effects of the Error, Barriers and Controls, Risk Priority Numbers, and Recommended Actions. This report summarizes findings and gives recommendations as determined by the data contained in appendix A. It also includes a discussion of technology barriers and challenges to performing task analyses, as well as lessons learned. The HF PFMEA table in appendix A recommends the use of accepted and required safety criteria in order to reduce the risk of human error. The items with the highest risk priority numbers should receive the greatest amount of consideration. Implementation of the recommendations will result in a safer operation for all personnel.

Diorio, Kimberly A.↗
NASA NTRS2007

Crew Exploration Vehicle Environmental Control and Life Support Development Status

The Crew Exploration Vehicle (CEV) is the first crew transport vehicle to be developed by the National Aeronautics and Space Administration (NASA) in the last thirty years. The CEV is being developed to transport the crew safely from the Earth to the Moon and back again. This year, the prime contractor has been selected, requirements have been refined, and development areas are being pursued. The Environmental Control and Life Support (ECLS) system, which includes the life support and active thermal control systems, is moving one year closer to performing on orbit.

Lewis, John F.↗
NASA NTRS2011

Humans in Space: Summarizing the Medico-Biological Results of the Space Shuttle Program

As we celebrate the 50th anniversary of Gagarin's flight that opened the era of Humans in Space we also commemorate the 30th anniversary of the Space Shuttle Program (SSP) which was triumphantly completed by the flight of STS-135 on July 21, 2011. These were great milestones in the history of Human Space Exploration. Many important questions regarding the ability of humans to adapt and function in space were answered for the past 50 years and many lessons have been learned. Significant contribution to answering these questions was made by the SSP. To ensure the availability of the Shuttle Program experiences to the international space community NASA has made a decision to summarize the medico-biological results of the SSP in a fundamental edition that is scheduled to be completed by the end of 2011 beginning 2012. The goal of this edition is to define the normal responses of the major physiological systems to short-duration space flights and provide a comprehensive source of information for planning, ensuring successful operational activities and for management of potential medical problems that might arise during future long-term space missions. The book includes the following sections: 1. History of Shuttle Biomedical Research and Operations; 2. Medical Operations Overview Systems, Monitoring, and Care; 3. Biomedical Research Overview; 4. System-specific Adaptations/Responses, Issues, and Countermeasures; 5. Multisystem Issues and Countermeasures. In addition, selected operational documents will be presented in the appendices. The chapters are written by well-recognized experts in appropriate fields, peer reviewed, and edited by physicians and scientists with extensive expertise in space medical operations and space-related biomedical research. As Space Exploration continues the major question whether humans are capable of adapting to long term presence and adequate functioning in space habitats remains to be answered We expect that the comprehensive review of the medico-biological results of the SSP along with the data collected during the missions on the space stations (Mir and ISS) provides a good starting point in seeking the answer to this question.

Risin, Diana↗
NASA NTRS1972

In-space propellant logistics. Volume 4: Project planning data

The prephase A conceptual project planning data as it pertains to the development of the selected logistics module configuration transported into earth orbit by the space shuttle orbiter. The data represents the test, implementation, and supporting research and technology requirements for attaining the propellant transfer operational capability for early 1985. The plan is based on a propellant module designed to support the space-based tug with cryogenic oxygen-hydrogen propellants. A logical sequence of activities that is required to define, design, develop, fabricate, test, launch, and flight test the propellant logistics module is described. Included are the facility and ground support equipment requirements. The schedule of activities are based on the evolution and relationship between the R and T, the development issues, and the resultant test program.

Source record↗
NASA NTRS1988

Incorporation of privacy elements in space station design

Privacy exists to the extent that individuals can control the degree of social contact that they have with one another. The opportunity to withdraw from other people serves a number of important psychological and social functions, and is in the interests of safety, high performance, and high quality of human life. Privacy requirements for Space Station crew members are reviewed, and architectual and other guidelines for helping astronauts achieve desired levels of privacy are suggested. In turn, four dimensions of privacy are discussed: the separation of activities by areas within the Space Station, controlling the extent to which astronauts have visual contact with one another, controlling the extent to which astronauts have auditory contact with one another, and odor control. Each section presents a statement of the problem, a review of general solutions, and specific recommendations. The report is concluded with a brief consideration of how selection, training, and other procedures can also help Space Station occupants achieve satisfactory levels of seclusion.

Harrison, Albert A.↗
NASA NTRS2004

Observing the Global Water Cycle from Space

This paper presents an approach to measuring all major components of the water cycle from space. Key elements of the global water cycle are discussed in terms of the storage of water-in the ocean, air, cloud and precipitation, in soil, ground water, snow and ice, and in lakes and rivers, and in terms of the global fluxes of water between these reservoirs. Approaches to measuring or otherwise evaluating the global water cycle are presented, and the limitations on known accuracy for many components of the water cycle are discussed, as are the characteristic spatial and temporal scales of the different water cycle components. Using these observational requirements for a global water cycle observing system, an approach to measuring the global water cycle from space is developed. The capabilities of various active and passive microwave instruments are discussed, as is the potential of supporting measurements from other sources. Examples of space observational systems, including TRMM/GPM precipitation measurement, cloud radars, soil moisture, sea surface salinity, temperature and humidity profiling, other measurement approaches and assimilation of the microwave and other data into interpretative computer models are discussed to develop the observational possibilities. The selection of orbits is then addressed, for orbit selection and antenna size/beamwidth considerations determine the sampling characteristics for satellite measurement systems. These considerations dictate a particular set of measurement possibilities, which are then matched to the observational sampling requirements based on the science. The results define a network of satellite instrumentation systems, many in low Earth orbit, a few in geostationary orbit, and all tied together through a sampling network that feeds the observations into a data-assimilative computer model.

Hildebrand, P. H.↗