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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 811 records · Page 45
All sourcesNASA NTRSDOE OSTI
NASA NTRS2001

Simulator Evaluation of Airborne Information for Lateral Spacing (AILS) Concept

The Airborne Information for Lateral Spacing (AILS) concept is designed to support independent parallel approach operations to runways spaced as close as 2500 ft. This report describes the AILS operational concept and the results of a ground-based flight simulation experiment of one implementation of this concept. The focus of this simulation experiment was to evaluate pilot performance, pilot acceptability, and minimum miss-distances for the rare situation in which all aircraft oil one approach intrudes into the path of an aircraft oil the other approach. Results from this study showed that the design-goal mean miss-distance of 1200 ft to potential collision situations was surpassed with an actual mean miss-distance of 2236 ft. Pilot reaction times to the alerting system, which was an operational concern, averaged 1.11 sec, well below the design-goal reaction time 2.0 sec.These quantitative results and pilot subjective data showed that the AILS concept is reasonable from an operational standpoint.

Abbott, Terence S.↗
NASA NTRS2000

Preliminary Analysis and Design of a Rocket Based Combined Cycle for Efficient Access to Space

Access to space is presently limited by cost. The cost of delivering a payload to low earth orbit (LEO) is on average $10,000 per pound of payload, in the United States. Much of this cost is incurred from the operation of vehicles developed with 30-40 year old technology. The old technology and design practices have resulted in expensive hardware and intensive maintenance requirements for current launch vehicles. In order to alleviate the cost factor, the technological advances throughout the next millennium must bring affordable development and a new invigorating desire to space exploration. National Aeronautical and Space Administration (NASA), Department of Defense (DOD), and private industry are addressing this issue by focusing on incremental improvements in the Earth- to Orbit (ETO) costs. These improvements have investigated two different approaches: 1) make space vehicles as inexpensive as possible (i.e. Evolved Expendable Launch Vehicle (EELV) and Delta IV) 2) make space vehicles as reusable as airplanes so that the initial cost of investment can be recaptured (i.e. Reusable Launch Vehicle (RLV), X-33, X-34, and X-37) These programs have made notable progress in new material, propulsion, structures, and avionics technologies, during the last 3-5 years. So far, these programs are targeted to reduce present costs by, as much as, five times the current cost. The year 2025 goal for continued space advancement is to have ETO costs reduced by a factor of ten (i.e., tenfold), as low as $100 - $200/lb payload. For the RLV, this goal translates into very low maintenance costs and higher expected reliability per flight must be obtained. Therefore, making higher launch rates possible. For the expendable vehicle, the cost of maintenance cost is minimal, but a greater reliability must exist to insure the payload; since, there would be no way to recover the payload if the mission was to an abort or failure. Overall the cost of vehicle, payload and operations of an expendable may be too high compared to those of the RLV.

Harris, Lawanna↗
NASA NTRS1976

OAST Space Theme Workshop. Volume 3: Working group summary. 1: Navigation, guidance, control (E-1) A. Statement. B. Technology needs (form 1). C. Priority assessment (form 2)

The six themes identified by the Workshop have many common navigation guidance and control needs. All the earth orbit themes have a strong requirement for attitude, figure and stabilization control of large space structures, a requirement not currently being supported. All but the space transportation theme have need for precision pointing of spacecraft and instruments. In addition all the themes have requirements for increasing autonomous operations for such activities as spacecraft and experiment operations, onboard mission modification, rendezvous and docking, spacecraft assembly and maintenance, navigation and guidance, and self-checkout, test and repair. Major new efforts are required to conceptualize new approaches to large space antennas and arrays that are lightweight, readily deployable, and capable of precise attitude and figure control. Conventional approaches offer little hope of meeting these requirements. Functions that can benefit from increasing automation or autonomous operations are listed.

Source record↗
NASA NTRS2019

Free Space Optics - Transportable Test Platform

The study examines potential approaches and benefits to government space agencies and industry regarding the development and testing of free space optics (FSO) satellite communication systems should government space agencies launch optical satellite payloads and/or develop a transportable test platform with which industry provided optical ground systems (OGSs) could interface. The study examines atmospheric and environmental effects on FSO networks, as well as the multitude of mitigation techniques available to compensate for those effects. Research suggests that there are a multitude of potential techniques that could be implemented to mitigate the adverse effects of atmospheric/environmental conditions, and to optimize the effectiveness of FSO networks. Testing and selection of this broad array of techniques is a prerequisite to making FSO space segment systems and OGSs interoperable. The study discusses testing that is required to define FSO standards. The establishment of interoperable standards is complicated by the existence of a multitude of potential schemes/specifications to address each mitigation/optimization challenge; very little is yet standardized. Standardization is further complicated by the fact that the selection of a design approach which benefits one consideration often disadvantages another consideration. Each mitigation techniques must be evaluated as an element of the complete system to gain an accurate understanding of its effects on system efficacy.

Haddad, George↗
NASA NTRS2018

Growth-Adapted Tensegrity Structures: A New Calculus for the Space Economy

We describe a novel approach to create and engineer an economically viable space habitat development technology, for deployment of a lightweight tensegrity habitat structure orbiting at Earth-Moon L2, where onboard robotic assets will use space-based materials to provide water for shielding, irrigation and life support, soil for ecosystem development, and to enable structural maintenance and enhancement. The habitat can become a tourist destination, an economic hub, and a multi-purpose research and support facility for lunar surface development and space ecosystem life sciences.

Materials↗
NASA NTRS2019

Measuring Metapopulation Characteristics of the Southeastern Beach Mouse on Kennedy Space Center using a Dynamic Habitat Occupancy Approach

The Cape Canaveral Barrier Island Complex (CCBIC) represents the largest (72 km) continuous coastal habitat supporting the core population of the threatened southeastern beach mouse (Peromyscus polionotus niveiventris) in Florida. Despite protection throughout the subspecies’ remaining range, storm activity during the past two decades has de-stabilized coastal dune and coastal strand habitat required for beach mouse survival. Our long-term goal is to provide information to the management process to ensure a sustainable population on the CCBIC in light of sea-level rise, extreme storm events, and continued land development supporting the multi-user spaceport.Because beach mice populations are affected by storms (hurricanes, tropical storms, nor’easters), it is important to understand the species-habitat relations during periods with and without storm impacts. Conventional wisdom is that coastal dune and coastal strand are the preferred habitats, but coastal scrub habitat may be important because it is less affected by storm impacts (e.g., overwash, escarpment, sand deposition, etc.) and thus may serve as a refugia. In addition, genetic studies have shown some evidence for reduced dispersal between regions on CCBIC (Kalkvik et al., 2012; Zimmerman et al., 2015). We compared site occupancy dynamics for coastal dune, coastal strand, and coastal scrub habitat over three quarters (seasons) and determined the pattern of spatial correlation in habitat occupancy dynamics for locations at a range of distances in coastal dune, coastal strand, and coastal scrub habitats along the Kennedy Space Center (KSC) coastline (Figures1 and 2). Although habitat occupancy is very useful for understanding species-habitat relationships,in its simplest form it ignores differences in abundance between sites. Because information on abundance may inform management efforts and provide knowledge regarding status of the population, we tested measuring abundance state based on the number of detections in tracking tubes. Small mammal populations often fluctuate in a cyclic manner over time. These fluctuations make populations more susceptible to extinction and make trend detection more difficult. Efficient methods of measuring abundance across time and space are needed for monitoring trends.The purpose of this project was to:1.Estimate southeastern beach mouse habitat occupancy parameters in coastal dune, coastal strand, and coastal scrub habitats using a combination of tracking tubes and traps; 2.Model the spatial relationships of the effect of habitat (coastal dune, coastal strand, and coastal scrub) on parameters as a function of distance; and 3.Compare the reliability and efficiency of our survey methods and evaluate the potential to develop an abundance index.

Eric Douglas Stolen↗
NASA NTRS1990

CCSDS - An approach to the definition of common standards for space data and information systems

The Consultative Committee for Space Data Systems (CCSDS) was formed in 1982 to develop common space system data structures, protocols, and interfaces which would facilitate mutual international support and interoperability. It soon emerged that CCSDS's activities exerted synergistic forces on systems development efforts. Currently, CCSDS is composed of both member-status and observer-status agencies; while only one member agency is admitted from any one country, multiple additional agencies may participate as observers. CCSDS recommendations to date have identified a common architectural approach for the handling and processing of space data.

Greene, Edward P.↗
NASA NTRS1982

Planning satellite communication services and spectrum-orbit utilization

The relationship between approaches to planning satellite communication services and spectrum-orbit utilization is considered, with emphasis on the fixed-satellite and the broadcasting-satellite services. It is noted that there are several possible approaches to planning space services, differing principally in the rigidity with which technical parameters are prescribed, in the time for which a plan remains in force, and in the procedures adopted for implementation and modifications. With some planning approaches, spectrum-orbit utilization is fixed at the time the plan is made. Others provide for greater flexibility by making it possible to postpone some decisions on technical parameters. In addition, the two political questions of what is equitable access and how it can be guaranteed in practice play an important role.

Sawitz, P. H.↗
NASA NTRS1983

Pyroelectric conversion in space: A conceptual design study

Pyroelectric conversion is potentially a very lightweight means of providing electrical power generation in space. Two conceptualized systems approaches for the direct conversion of heat (from sunlight) into electrical energy using the pyroelectric effect of a new class of polar polymers were evaluated. Both of the approaches involved large area thin sheets of plastic which are thermally cycled by radiative input and output of thermal energy. The systems studied are expected to eventually achieve efficiencies of the order of 8% and may deliver as much as one half kilowatt per kilogram. In addition to potentially very high specific power, the pyroelectric conversion approaches outlined appear to offer low cost per watt in the form of an easily deployed, flexible, strong, electrically ""self-healing'', and high voltage sheet. This study assessed several potential problems such as plasma interactions and radiation degradation and suggests approaches to overcome them. The fundamental technological issues for space pyroelectric conversion are: (1) demonstration of the conversion cycle with the proposed class of polymers, (2) achievement of improved dielectric strength of the material, (3) demonstration of acceptable plasma power losses for low altitude, and (4) establishment of reasonable lifetime for the pyroelectric material in the space environment. Recommendations include an experimental demonstration of the pyroelectric conversion cycle followed by studies to improve the dielectric strength of the polymer and basic studies to discover additional pyroelectric materials.

Olsen, R. B.↗
NASA NTRS1998

Recent Results of NASA's Space Environments and Effects Program

The Space Environments and Effects (SEE) Program is a multi-center multi-agency program managed by the NASA Marshall Space Flight Center. The program evolved from the Long Duration Exposure Facility (LDEF), analysis of LDEF data, and recognition of the importance of the environments and environmental effects on future space missions. It is a very comprehensive and focused approach to understanding the space environments, to define the best techniques for both flight and ground-based experimentation, to update the models which predict both the environments and the environmental effects on spacecraft, and finally to ensure that this information is properly maintained and inserted into spacecraft design programs. Formal funding of the SEE Program began initially in FY95. A NASA Research Announcement (NRA) solicited research proposals in the following categories: 1) Engineering environment definitions; 2) Environments and effects design guidelines; 3) Environments and effects assessment models and databases; and, 4) Flight/ground simulation/technology assessment data. This solicitation resulted in funding for eighteen technology development activities (TDA's). This paper will present and describe technical results rom the first set of TDA's of the SEE Program. It will also describe the second set of technology development activities which are expected to begin in January 1998. These new technology development activities will enable the SEE Program to start numerous new development activities in support of mission customer needs.

Minor, Jody L.↗
NASA NTRS2000

NASA's Space Environments and Effects Program: Technology for the New Millennium

Current trends in spacecraft development include the use of advanced technologies while maintaining the "faster, better, cheaper" philosophy. Spacecraft designers are continually designing with smaller and faster electronics as well as lighter and thinner materials providing better performance, lower weight, and ultimately lower costs. Given this technology trend, spacecraft will become increasingly susceptible to the harsh space environments, causing damaging or even disabling effects on space systems. NASA's Space Environments and Effects (SEE) Program defines the space environments and provides advanced technology development to support the design, development, and operation of spacecraft systems that will accommodate or mitigate effects due to the harsh space environments. This Program provides a comprehensive and focused approach to understanding the space environment, to define the best techniques for both flight and ground-based experimentation, to update the models which predict both the environments and the environmental effects on spacecraft, and finally to ensure that this multitudinous information is properly maintained and inserted into spacecraft design programs. A description of the SEE Program, its accomplishments, and future activities is provided.

Hardage, Donna M.↗
NASA NTRS2001

NASA's Space Environments and Effects (SEE) Program

The return of the Long Duration Exposure Facility (LDEF) in 1990 brought a wealth of space exposure data on materials, paints, solar cells, adhesives and other data on the many space environments. The effects of the harsh space environments can provide damaging or even disabling effects on a spacecraft, its sub-systems, materials and instruments. In partnership with industry, academia, and other US and international government agencies, the National Aeronautics & Space Administration's (NASA's) Space Environments & Effects (SEE) Program defines the space environments and provides technology development to accommodate or mitigate these harmful environments on the spacecraft. This program (agency-wide in scope but managed at the Marshall Space Flight Center) provides a very comprehensive and focused approach to understanding the space environment. It does this by defining the best techniques for both flight- and groundbased experimentation, updating models which predict both the environments and the environmental effects on spacecraft and ensuring that this information is properly maintained and inserted into spacecraft design programs. This paper will describe the current SEE Program and discuss several current technology development activities associated with the spacecraft charging phenomenon.

Minor, Jody↗
NASA NTRSDate not supplied

Explicit Discontinuous Galerkin Methods for Conservation Laws

The two explicit DG methods in this study are based on a ‘predictor-corrector’ formulation, the first introduced by Lörcher, Gassner, and Munz (2007, 2008) called space–time expansion discontinuous Galerkin or STE-DG scheme, and the second, introduced independently by the author (Huynh 2006, 2013) called the upwind moment scheme. The predictor step of the two methods is essentially identical using a Cauchy-Kovalevsky (CK) procedure, which involves no interaction of the data among neighboring cells. The corrector step also shares the same space-time integration formulation and is where interaction of the data among neighboring cells takes place; the difference, however, is in how the resulting space-time volume integral is estimated. As a consequence of the different estimates, for the case of advection in one spatial dimension (1D), the moment scheme has a CFL (Courant-Friedrichs-Lewy) condition of 1 for all p and is accurate to order 2p+1, i.e., it possesses the super accuracy property, whereas the STE-DG method has a more restrictive CFL condition and is accurate to the expected order of p+1. For 1D advection, compared with the CFL conditions of 1/(2p+1) of standard RK-DG (Runge-Kutta) scheme where space and time discretization are of the same order, the moment scheme allows a significantly larger time step size. It also turns out that the scheme yields a result identical to Van Leer’s scheme III (1977), which amounts to shifting the data a distance of advection corresponding to the time step and projecting the result onto the space of polynomial solutions. Contrary to Van Leer’s approach, however, the space-time ‘predictor-corrector’ formulation facilitates extensions to the case of systems of equations. Concerning 2D extensions, in the case of advection, when the flow is along the diagonal direction, the CFL conditions for the moment schemes become restrictive as will be shown by Fourier (Von Neumann) stability and accuracy analyses. Since the moment scheme employs the right Radau points as collocation points in time, the method is closely related to the implicit Radau IIA scheme, which is stable for any time step size. The role of Radau IIA in relieving stability restriction for these explicit DG schemes remains to be explored

Discontinuous Galerkin↗
NASA NTRS1999

Novel Approaches to Cellular Transplantation from the US Space Program

Research in the treatment of type I diabetes is entering a new era that takes advantage of our knowledge in an ever increasing variety of scientific disciplines. Some may originate from very diverse sources, one of which is the Space Program at National Aeronautics and Space Administration (NASA). The Space Program contributes to diabetes-related research in several treatment modalities. As an ongoing effort for medical monitoring of personnel involved in space exploration activities NASA and the extramural scientific community investigate strategies for noninvasive estimation of blood glucose levels. Part of the effort in the space protein crystal growth program is high-resolution structural analysis insulin as a means to better understand the interaction with its receptor and with host immune components and as a basis for rational design of a "better" insulin molecule. The Space Program is also developing laser technology for potential early cataract detection as well as a noninvasive analyses for addressing preclinical diabetic retinopathy. Finally, NASA developed an exciting cell culture system that affords some unique advantages in the propagation and maintenance of mammalian cells in vitro. The cell culture system was originally designed to maintain cell suspensions with a minimum of hydrodynamic and mechanical sheer while awaiting launch into microgravity. Currently the commercially available NASA bioreactor (Synthecon, Inc., Houston, TX) is used as a research tool in basic and applied cell biology. In recent years there is continued strong interest in cellular transplantation as treatment for type I diabetes. The advantages are the potential for successful long-term amelioration and a minimum risk for morbidity in the event of rejection of the transplanted cells. The pathway to successful application of this strategy is accompanied by several substantial hurdles: (1) isolation and propagation of a suitable uniform donor cell population; (2) management of host immune rejection; (3) protection from the autoimmune component of the disease; and (4) anatomic placement of the engrafted cells that permits timely response to blood sugar levels as well as effective release and deployment of insulin. Bioreactor technology may provide some critical advances for surmounting some of these scientific hurdles. The NASA bioreactor is a horizontally rotating cylinder that is completely filled with culture medium. Gaseous exchange is maintained by a concentric cylinder of permeable silicon. In slow rotation (15-25 rpm) particles of small mass such as cells and tissue aggregates remain suspended in the rotating body of fluid. This novel approach suspends cells without stirring thus, allowing objects of different size mass to colocate and interact in a very low shear environment. In fact, analysis of the forces acting on individual cells in the rotating bioreactor reveals that the cells are continuously falling through the fluid medium. The conditions in the bioreactor permit assembly of cells into aggregates. three-dimensional tissue growth, synthesis of intercellular matrix,10 differentiation, and some sinusoid formations that may serve as a surrogate vasculature for larger tissue segments.

Pellis, Neal R.↗
NASA NTRS1982

Electric and magnetic fields

A number of energy momentum anomalies are described that result from the use of Abraham-Lorentz electromagnetic theory. These anomalies have in common the motion of charged bodies or current carrying conductors relative to the observer. The anomalies can be avoided by using the nonflow approach, based on internal energy of the electromagnetic field. The anomalies can also be avoided by using the flow approach, if all contributions to flow work are included. The general objective of this research is a fundamental physical understanding of electric and magnetic fields which, in turn, might promote the development of new concepts in electric space propulsion. The approach taken is to investigate quantum representations of these fields.

Kaufman, H. R.↗
NASA NTRS2021

A Paradigm Shift in Quality Assurance of COTS Capacitors for Space Applications

Limitations of a traditional approach to screening and qualification of COTS capacitors for space applications that is based on burn-in and life test requirements described in the relevant military specifications are analyzed. An alternative approach that is originated from analysis of highly accelerated life testing (HALT) of capacitors susceptible to wear-out failures and allows for assessments of the risks of failure during the mission is suggested. Examples include results of reliability testing of advanced BME ceramic capacitors, polymer tantalum capacitors and multianode manganese oxide tantalum capacitors.

Alexander A Teverovsky↗
NASA NTRSDate not supplied

Thermoplastic Composite Lunar Tower Truss Structure: Design Development and Verification Plans

The National Aeronautics and Space Administration (NASA) Space Technology and Mission Directorate (STMD) is advancing thermoplastic composite (TPC) technologies for exploration missions. The Technology Development for Exploration Applications (TDEA) project goals are to develop and mature TPC materials, designs, analyses tools and techniques, and mature manufacturing processes. This includes development of manufacturing and joining approaches relevant to space environments. To these ends TDEA endeavors toward demonstrating a TPC truss structure for a lunar tower configuration. The design, predicated on robotic assembly, uses open section truss elements fused to a joint splice plate, without a structural adhesive. This presentation details the TDEA lunar truss structure design development approach including design heritage, the requirements established, the mechanical design and analyses, and thermal analyses demonstrating structural requirements conformance, as well as planned building block verification efforts either underway or planned. The mechanical analyses show the most severe environment is a moon-quake the truss dynamic responses. The thermal analyses show the extreme cold for on-orbit welding, the window for less severe on-orbit welding, as well as the large thermal gradients on the truss. The building block approach shown includes ultrasonic welding and lap shear coupon testing on various truss element thicknesses and layups. Knockdown factor determinations due to lunar dust contamination (simulated) and effects of welding in a vacuum are presented. The most highly loaded truss joint configuration sub-element verification test matrix is outlined. Lastly, plans to build, inspect, and test a 2-bay truss representative unit cell that is 1.5 meters by 1.5 meters by 3.0 meters tall are detailed.

Lunar Tower↗
NASA NTRS2015

Space Resource Utilization: Near-Term Missions and Long-Term Plans for Human Exploration

NASA's Human Exploration Plans: A primary goal of all major space faring nations is to explore space: from the Earth with telescopes, with robotic probes and space telescopes, and with humans. For the US National Aeronautics and Space Administration (NASA), this pursuit is captured in three important strategic goals: 1. Ascertain the content, origin, and evolution of the solar system and the potential for life elsewhere, 2. Extend and sustain human activities across the solar system (especially the surface of Mars), and 3. Create innovative new space technologies for exploration, science, and economic future. While specific missions and destinations are still being discussed as to what comes first, it is imperative for NASA that it foster the development and implementation of new technologies and approaches that make space exploration affordable and sustainable. Critical to achieving affordable and sustainable human exploration beyond low Earth orbit (LEO) is the development of technologies and systems to identify, extract, and use resources in space instead of bringing everything from Earth. To reduce the development and implementation costs for space resource utilization, often called In Situ Resource Utilization (ISRU), it is imperative to work with terrestrial mining companies to spin-in/spin-off technologies and capabilities, and space mining companies to expand our economy beyond Earth orbit. In the last two years, NASA has focused on developing and implementing a sustainable human space exploration program with the ultimate goal of exploring the surface of Mars with humans. The plan involves developing technology and capability building blocks critical for sustained exploration starting with the Space Launch System (SLS) and Orion crew spacecraft and utilizing the International Space Station as a springboard into the solar system. The evolvable plan develops and expands human exploration in phases starting with missions that are reliant on Earth, to performing ever more challenging and longer duration missions in cis-lunar space and beyond, to eventually being independent from Earth. The goal is no longer just to reach a destination, but to enable people to work, learn, operate, and live safely beyond the Earth for extended periods of time, ultimately in ways that are more sustainable and even indefinite.

Sanders, Gerald B.↗