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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

Photovoltaic power-system options for the manned space construction base

The function of the proposed manned Space Construction Base (SCB) is to provide a permanent manned orbital facility for the construction and operation of a variety of space experiments, ranging from a space-processing development to on-orbit-constructed microwave radiometers and antennas. A typical SCB system might reach initial operational capability in low earth orbit in 1985, have a 10-year mission duration, and have an initial power requirement of 50 kWe. A summary of the requirements imposed by the SCB on the electrical power system (EPS) is presented in a table. Attention is given to EPS options, baseline power platform system operations, an energy storage system evaluation, advanced-technology NiCd batteries and lifetime, and orbital buildup operations.

Mckhann, G. G.↗
NASA NTRS2011

Use It or Lose It: Skeletal Muscle Function and Performance Results from Space Shuttle

The Space Shuttle Program provided a wealth of valuable information regarding the adaptations of skeletal muscle to weightlessness. Studies conducted during the Extended Duration Orbiter Medical Project (EDOMP) represented ground breaking work on the effects of spaceflight on muscle form and function from applied human research to cellular adaptations. Results from detailed supplementary objective (DSO) 477 demonstrated that muscle strength losses could occur rapidly in response to short-duration spaceflight. The effects of spaceflight-induced unloading were primarily restricted to postural muscles such as those of the back as well as the knee extensors. DSO 606 provided evidence from MRI that the observed strength losses were partially accounted for by a reduction in the size of the individual muscles. Muscle biopsy studies conducted during DSO 475 were able to show muscle atrophy in individual muscle fibers from the quadriceps muscles. Reduced quadriceps muscle size and strength was also observed during the 17-d Life and Microgravity Spacelab mission aboard STS-78. Multiple maximal strength tests were conducted in flight on the calf muscles and it has been hypothesized that these high force contractions may have acted as a countermeasure. Muscle fiber mechanics were studied on calf muscle samples pre- and postflight. While some responses were crewmember specific, the general trend was that muscle fiber force production dropped and shortening velocity increased. The increased shortening velocity helped to maintain muscle fiber power. Numerous rodent studies performed during Shuttle missions suggest that many of the effects reported in Shuttle crewmembers could be due to lesions in the cellular signaling pathways that stimulate protein synthesis as well as an increase in the mechanisms that up-regulate protein breakdown. The results have important implications regarding the overall health and performance capabilities of future crewmembers that will venture beyond low-Earth orbit. Learning Objective: Overview of the Space Shuttle Program regarding adaptive changes in skeletal muscle function and performance, including what was learned from research and what was implemented for countermeasures.

Ryder, Jeffrey↗
NASA NTRS2004

Electronics packaging considerations for space applications

The functionality of spacecraft electronics must be maintained in the harsh environments found in space. The radiation environments can consist of either low-energy x-rays at the surface of the spacecraft or high-energy electrons, high-energy protons and high-energy photons withn the spacecraft.

electronics packaging↗
NASA NTRS1986

An expert systems approach to automated fault management in a regenerative life support subsystem

This paper describes FIXER, a prototype expert system for automated fault management in a regenerative life support subsystem typical of Space Station applications. The development project provided an evaluation of the use of expert systems technology to enhance controller functions in space subsystems. The software development approach permitted evaluation of the effectiveness of direct involvement of the expert in design and development. The approach also permitted intensive observation of the knowledge and methods of the expert. This paper describes the development of the prototype expert system and presents results of the evaluation.

Malin, J. T.↗
NASA NTRS1997

Altered vestibular function in fetal and newborn rats gestated in space

Researchers evaluated vestibular development and function in rat pups flown during gestation on the NASA-NIH R1 and R2 missions. Fetal and postnatal vestibular function were examined. Altered vestibular-mediated responses in the experimental fetal pups are attributed to either direct effect of gravity on the vestibular system or indirect effects of microgravity transduced through the mother. The postnatal tests confirmed the hypothesis that the vestibular system continually adapts and responds to tonic stimulation.

Non-NASA Center↗
NASA NTRS1986

Environmental control/life support system for Space Station

The functional, operational, and design load requirements for the Environmental Control/Life Support System (ECLSS) are described. The ECLSS is divided into two groups: (1) an atmosphere management group and (2) a water and waste management group. The interaction between the ECLSS and the Space Station Habitability System is examined. The cruciform baseline station design, the delta and big T module configuration, and the reference Space Station configuration are evaluated in terms of ECLSS requirements. The distribution of ECLSS equipment in a reference Space Station configuration is studied as a function of initial operating conditions and growth orbit capabilities. The benefits of water electrolysis as a Space Station utility are considered.

Miller, C. W.↗
NASA NTRS2018

Needs and Opportunities in the Development of Advanced Materials and Manufacturing Methods for Future Long-Duration Human Space Exploration

Weight, functionality, and sustainability are all critical concerns for future, long-duration, human exploration of space. Exploration missions will be mass-limited, since the amount of supplies and instruments that future astronauts will be able to take with them will be limited by launch vehicle and spacecraft mass and efficiency. Astronauts will need to have the capability to repair or replace worn-out or broke hardware and produce new components to be able to function for long periods at locations far-removed from Earth. Ultra-lightweight, multifunctional materials will be required to enable significant reductions in launch vehicle, spacecraft, and habitat mass in order to maximize payload. "Mass-less Exploration" concepts must be developed that will recycle materials and waste and convert available planetary materials into new feedstock materials and utilize in-space additive manufacturing to use these materials to produce the

composites↗
NASA NTRS1986

NASA's life sciences program

NASA space missions from the Mercury through the Shuttle program have provided successively more data on the ability of humans to function in space for progressively longer periods of time. The Skylab program encouraged cooperation between medical and engineering personnel in the design of space suits, diet, food preparation, and cleanliness procedures and equipment, and the man-machine interface. Research is now concentrated on supporting man in space, evaluating the effects of the microgravity environment on humans, and modeling encounters with extraterrestrial life and the effects of human activities on terrestrial biota. Current levels of understanding of the physiological causes of human health problems produced by long-duration spaceflight are summarized. Experiments planned for the Shuttle, Spacelab, and the Space Station are outlined, noting the long-term goal of configuring the Space Station so that only food and hydrazine are needed to complete the life support system cycle.

Soffen, Gerald A.↗
NASA NTRS2005

Effects of space flight conditions on the function of the immune system and catecholamine production simulated in a rodent model of hindlimb unloading

The rodent model of hindlimb unloading has been successfully used to simulate some of the effects of space flight conditions. Previous studies have indicated that mice exposed to hindlimb-unloading conditions have decreased resistance to infections compared to restrained and normally housed control mice. OBJECTIVE: The purpose of this study was to clarify the mechanisms involved in resistance to infection in this model by examining the effects of hindlimb unloading on the function of the immune system and its impact on the production of catecholamines. METHODS: Female Swiss Webster mice were hindlimb-unloaded during 48 h and the function of the immune system was assessed in spleen and peritoneal cells immediately after this period. In addition, the kinetics of catecholamine production was measured throughout the hindlimb-unloading period. RESULTS: The function of the immune system was significantly suppressed in the hindlimb-unloaded group compared to restrained and normally housed control mice. Levels of catecholamines were increased in the hindlimb-unloaded group and peaked at 12 h following the commencement of unloading. CONCLUSION: These results suggest that physiological responses of mice are altered early after hindlimb unloading and that catecholamines may play a critical role in the modulation of the immune system. These changes may affect the ability of mice to resist infections. Copyright (c) 2005 S. Karger AG, Basel.

NASA Discipline Regulatory Physiology↗
NASA NTRS1997

Analysis of ripple formation in single crystal spot welds

Stationary spot welds have been made at the (001) surface of Fe-l5%Ni-15%Cr single crystals using a Gas Tungsten Arc (GTA). On the top surface of the spot welds, very regular and concentric ripples were observed after solidification by differential interference color microscopy. Their height (typically 1--5 micrometers and spacing, typically approximately 60 micrometers) decreased with the radius of the pool. These ripples were successfully accounted for in terms of capillary-wave theory using the fundamental mode frequency f(sub 0) given by the first zero of the zero-order Bessel function. The spacing d between the ripples was then equated to v(sub s)/f(sub 0), where v(sub s) is the solidification rate. From the measured ripple spacing, the velocity of the pool was deduced as a function of the radius, and this velocity was in good agreement with the results of a heat-flow simulation.

Rappaz, M.↗
NASA NTRS1998

Video Guidance Sensor Flight Experiment Results

NASA's Marshall Space Flight Center flew on the STS-87 mission an active sensor system, the Video Guidance Sensor (VGS), to demonstrate its functioning in space and to collect performance data. The VGS was designed to provide near-range sensor data as part of an automatic rendezvous and docking system. The sensor determines the relative positions and attitudes between the active sensor and the passive target. The VGS uses laser diodes to illuminate retro-reflectors in the target, a solid-state camera to detect the return from the target, and a frame grabber and digital signal processor to convert the video information into the relative positions and attitudes. The system is designed to operate with the target within a relative azimuth of +/- 9.5 degrees and a relative elevation of +/- 7.5 degrees. The system will acquire and track the target within that field-of-view anywhere from 1.5 meters to 110 meters range, and is designed to acquire at relative attitudes of +/- 10 degrees in pitch and yaw and at any roll angle. The data is output from the sensor at 5 Hz, and the target and sensor software have been designed to permit two independent sensors to operate simultaneously (in order to allow for redundancy). The data from the flight experiment includes raw video data from the VGS camera, relative position and attitude measurements from the VGS to the target, independent hand-held laser ranges from the Shuttle Aft Flight Deck to the target, and Remote Manipulator System position data to correlate with the VGS data. The experiment was quite successful and returned much useful information. The experience gained from the design and flight of this experiment will lead to improved video sensors in the future.

Howard, Richard T.↗
NASA NTRS2016

A Quality Function Deployment Method Applied to Highly Reusable Space Transportation

This paper will describe a Quality Function Deployment (QFD) currently in work the goal of which is to add definition and insight to the development of long term Highly Reusable Space Transportation (HRST). The objective here is twofold. First, to describe the process, the actual QFD experience as applies to the HRST study. Second, to describe the preliminary results of this process, in particular the assessment of possible directions for future pursuit such as promising candidate technologies or approaches that may finally open the space frontier. The iterative and synergistic nature of QFD provides opportunities in the process for the discovery of what is key in so far as it is useful, what is not, and what is merely true. Key observations on the QFD process will be presented. The importance of a customer definition as well as the similarity of the process of developing a technology portfolio to product development will be shown. Also, the relation of identified cost and operating drivers to future space vehicle designs that are robust to an uncertain future will be discussed. The results in particular of this HRST evaluation will be preliminary given the somewhat long term (or perhaps not?) nature of the task being considered.

hypersonics↗
NASA NTRS1990

Trapping saturation of the bump-on-tail instability and electrostatic harmonic excitation in earth's foreshock

The Vlasov simulation is used to examine the trapping saturation of the bump-on-tail instability both with and without mode-mode coupling and subsequent harmonic excitation. It is found that adding the pumped harmonic modes leads to a significant difference in the behavior of the phase-space distribution function near the unstable bump at the saturation time of the instability. The pumped modes permit rapid plateau formation on the space-averaged velocity distribution, in effect preventing the onset of the quasi-linear velocity-diffusion saturation mechanism.

Klimas, Alexander J.↗
NASA NTRS1994

Antenna-assembling mechanism test on ETS-7

The Communications Research Laboratory plans to test an antenna-assembling mechanism on the Engineering Test Satellite 7. The test is one of the application missions for the space robotics experiments that will be conducted mainly by the National Space Development Agency of Japan (NASDA). The purpose of the test is to verify the ability of the antenna assembling mechanism to function in space and to experiment on the teleoperation of a space robot to develop antenna-assembling technology. We present the test experiment plans and the outline of the onboard assembling mechanism.

Suzuki, Yoshiaki↗
NASA NTRS1992

Human reproductive issues in space

A review of reproductive functioning in animal species studied during space flight demonstrated that most species were affected significantly by the absence of gravity and/or the presence of radiation. These two factors induced alterations in normal reproductive functioning independently of, as well as in combination with, each other. Based on animal models, several potential problem areas regarding human reproductive physiology and functioning in the space environment were identified. While there are no current space flight investigations, the animal studies suggest priorities for future research in human reproduction. Such studies will be critical for the successful colonization of the space frontier.

Santy, Patricia A.↗
NASA NTRS1984

Space station automation study. Volume 1: Executive summary. Autonomous systems and assembly

The space station automation study (SSAS) was to develop informed technical guidance for NASA personnel in the use of autonomy and autonomous systems to implement space station functions. The initial step taken by NASA in organizing the SSAS was to form and convene a panel of recognized expert technologists in automation, space sciences and aerospace engineering to produce a space station automation plan.

Source record↗
NASA NTRS1985

Alternative approximation concepts for space frame synthesis

A method for space frame synthesis based on the application of a full gamut of approximation concepts is presented. It is found that with the thoughtful selection of design space, objective function approximation, constraint approximation and mathematical programming problem formulation options it is possible to obtain near minimum mass designs for a significant class of space frame structural systems while requiring fewer than 10 structural analyses. Example problems are presented which demonstrate the effectiveness of the method for frame structures subjected to multiple static loading conditions with limits on structural stiffness and strength.

Lust, R. V.↗
NASA NTRS2003

The Logical Extension

The same software controlling autonomous and crew-assisted operations for the International Space Station (ISS) is enabling commercial enterprises to integrate and automate manual operations, also known as decision logic, in real time across complex and disparate networked applications, databases, servers, and other devices, all with quantifiable business benefits. Auspice Corporation, of Framingham, Massachusetts, developed the Auspice TLX (The Logical Extension) software platform to effectively mimic the human decision-making process. Auspice TLX automates operations across extended enterprise systems, where any given infrastructure can include thousands of computers, servers, switches, and modems that are connected, and therefore, dependent upon each other. The concept behind the Auspice software spawned from a computer program originally developed in 1981 by Cambridge, Massachusetts-based Draper Laboratory for simulating tasks performed by astronauts aboard the Space Shuttle. At the time, the Space Shuttle Program was dependent upon paper-based procedures for its manned space missions, which typically averaged 2 weeks in duration. As the Shuttle Program progressed, NASA began increasing the length of manned missions in preparation for a more permanent space habitat. Acknowledging the need to relinquish paper-based procedures in favor of an electronic processing format to properly monitor and manage the complexities of these longer missions, NASA realized that Draper's task simulation software could be applied to its vision of year-round space occupancy. In 1992, Draper was awarded a NASA contract to build User Interface Language software to enable autonomous operations of a multitude of functions on Space Station Freedom (the station was redesigned in 1993 and converted into the international venture known today as the ISS)

Source record↗