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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 217 records · Page 12
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NASA NTRS1991

Beyond the Baseline 1991: Proceedings of the Space Station Evolution Symposium. Volume 2: Space Station Freedom, part 2

Individual presentations delivered at the Space Station Evolution Symposium in League City, Texas, on August 6, 7, and 8, 1991 are given in viewgraph form. Personnel responsible for Advanced Systems Studies and Advanced Development within the Space Station Freedom Program reported on the results of their work to date. Special attention is given to highlighting changes made during restructuring; a description of the growth paths through the follow-on and evolution stages; identification of the minimum impact provisions to allow flexibility in the baseline; and identification of enhancing and enabling technologies.

Source record↗
NASA NTRS1991

Beyond the Baseline 1991: Proceedings of the Space Station Evolution Symposium. Volume 1: Space Station Freedom, part 2

This report contains the individual presentations delivered at the Space Station Evolution Symposium. The results of Space Station Freedom Advanced Studies provide a road map for the evolution of Freedom in terms of user requirements, utilization and operations concepts, and growth options for distributed systems. Regarding these specific systems, special attention is given to: highlighting changes made during restructuring; description of growth paths through the follow-on and evolution phases; identification of minimum impact provisions to allow flexibility in the baseline; and identification of enhancing and enabling technologies.

Source record↗
NASA NTRS1991

Beyond the Baseline 1991: Proceedings of the Space Station Evolution Symposium. Volume 2: Space Station Freedom, part 1

The results from the Advanced Systems Study and Advanced Development within the Space Station Freedom (SSF) Program are reported. The results show the evolution of the SSF in terms of user requirements, utilization and operations concepts, and growth options for distributed systems. Special attention is given to: highlighting changes made during restructuring; description of growth paths through the follow-on and evolution phases; identification of minimum-impact provisions to allow flexibility in the baseline; and identification of enhancing and enabling technologies. Products of these tasks include: engineering fidelity demonstrations and evaluations of advanced technology; detailed requirements, performance specifications, and design accommodations for insertion of advanced technology; and mature technology, tools, applications for SSF flight, ground, and information systems.

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NASA NTRS1992

Evolution of isotopic signatures in lunar-regolith nitrogen - Noble gases and nitrogen in grain-size fractions from regolith breccia 79035

Ilmenite and pyroxene grain-size separates from 79035 were analyzed for trapped N; the ilmenite was also analyzed for trapped Xe. Ilmenite N contains two or more isotopically distinct trapped components differing in release temperature and therefore plausibly in implantation energy. The isotopically light, higher-temperature (higher-energy?) component has a delta N-15 value equal to -180 percent, significantly above the minimum value observed in bulk 79035, suggesting that parts of 79035 were exposed on the lunar surface earlier than the ilmenite. Using trapped Ar-40/Ar-36 and cosmogenic Ne-21 (Benkert, 1989) a compaction age of about 1 Ga was derived for the ilmenite. This implies a considerably more recent exposure than previously thought, and suggests that the long-term change in delta N-15 of regolith N was more rapid than generally believed. Comparison of these results with those for black/orange glass from 74001/74002 (compaction age 3.7 Ga; delta N-15 in the range -36 to +18 percent (Kerridge et al., 1991) indicates that the long-term trend may have followed a complex evolutionary path. Data for 79035 pyroxenes are consistent with the ilmenite compaction age but suggest a more complex exposure history.

Kerridge, J. F.↗
NASA NTRS1992

A path to in-space welding and to other in-space metal processing technologies using Space Shuttle small payloads

As we venture into space, it becomes necessary to assemble, expand, and repair space-based structures for our housing, research, and manufacturing. The zero gravity-vacuum of space challenges us to employ construction options which are commonplace on Earth. Rockwell International (RI) has begun to undertake the challenge of space-based construction via numerous options, of which one is welding. As of today, RI divisions have developed appropriate resources and technologies to bring space-based welding within our grasp. Further work, specifically in the area of developing space experiments to test RI technology, is required. RI Space Welding Project's achievements to date, from research and development (R&E) efforts in the areas of microgravity, vacuum, intra- / extra- vehicular activity and spinoff technologies, are reviewed. Special emphasis is given to results for G-169's (Get Away Special) microgravity flights aboard a NASA KC-135. Based on these achievements, a path to actual development of a space welding system is proposed with options to explore spinoff in-space metal processing technologies. This path is constructed by following a series of milestone experiments, of which several are to utilize NASA's Shuttle Small Payload Programs. Conceptual designs of the proposed shuttle payload experiments are discussed with application of lessons learned from G-169's design, development, integration, testing, safety approval process, and KC-135 flights.

Tamir, David↗
NASA NTRS1992

Cometary orbital evolution in the outer planetary region

Numerical integrations of fictitious objects are carried out in order to elucidate the dynamical behavior of potential short-period comets when they move in orbits at distances from the Sun comparable to those of Uranus and Neptune. As in the case of observed short-period comets, close encounters with the planets play a major role for the orbital evolution, and this is especially true for encounters with initial orbits nearly tangent to that of the planet. A comparison with integrations in which the planetary masses are larger by a factor 10 shows that, in the latter case, the orbital evolution is greatly accelerated, but the dynamical paths in phase space followed by the comets are altered.

Manara, Allesandro↗
NASA NTRS1997

Single Close Encounters do not make Eccentric Planetary Orbits

The recent discovery of a planet in an orbit with eccentricity e = 0.63 +/- 0.08 around the solar-type star 16 Cyg B, together with earlier discoveries of other planets in orbits of significant eccentricity, raises the question of the origin of these orbits, so unlike the nearly circular orbits of our solar system. In this paper I consider close encounters between two planets, each initially in a nearly circular orbit (but with sufficient eccentricity to permit the encounter). Such encounters are described by a two-body approximation, in which the effect of the attracting star is neglected, and by the approximation that their separation vector follows a nearly parabolic path. A single encounter cannot produce the present state of these systems, in which one planet is in an eccentric orbit and the other has apparently been lost. Even if the requirement that the second planet be lost is dropped, nearly circular orbits cannot scatter into eccentric ones.

Katz, J. I.↗
NASA NTRS2000

Cricket Ball Aerodynamics: Myth Versus Science

Aerodynamics plays a prominent role in the flight of a cricket ball released by a bowler. The main interest is in the fact that the ball can follow a curved flight path that is not always under the control of the bowler. ne basic aerodynamic principles responsible for the nonlinear flight or "swing" of a cricket ball were identified several years ago and many papers have been published on the subject. In the last 20 years or so, several experimental investigations have been conducted on cricket ball swing, which revealed the amount of attainable swing, and the parameters that affect it. A general overview of these findings is presented with emphasis on the concept of late swing and the effects of meteorological conditions on swing. In addition, the relatively new concept of "reverse" swing, how it can be achieved in practice and the role in it of ball "tampering", are discussed in detail. A discussion of the "white" cricket ball used in last year's World Cup, which supposedly possesses different swing properties compared to a conventional red ball, is also presented.

Mehta, Rabindra D.↗
NASA NTRS2000

A Network Mission: Completing the Scientific Foundation for the Exploration of Mars

Despite recent setbacks and vacillations in the Mars Surveyor Program, in many respects the exploration of Mars has historically followed a relatively logical path. Early fly-bys provided brief glimpses of the planet and paved the way for the initial orbital reconnaissance of Mariner 9. The Viking orbiters completed the initial survey, while the Viking landers provided our first close-up look at the surface. Essentially, Mars Pathfinder served a similar role, giving a brief look at another place on the surface. And finally, Mars Global Surveyor (and the up-coming orbital mission in 2001) are taking the next step in providing in-depth, global observations of many of the fundamental characteristics of the planet, as well as selected high-resolution views of the surface. With this last step we are well on our way to acquiring the global scientific context that is necessary both for understanding Mars in general, its origin and evolution, and for use as a basis to plan and execute the next level of focused investigations. However, even with the successful completion of these missions this context will be incomplete. Whereas we now know a great deal about the surface of Mars in a global sense, we know very little about its interior, even at depths of only a meter or so. Also, as most of this information has been acquire by remote sensing, we still lack much of the bridging knowledge between the global view and the processes and character of the surface environments themselves. Thus, in many ways we lack sufficient fundamental understanding to intelligently cast the critical investigations into important questions of the origins and evolution of Mars in general, and in particular, life. The next step in building our understanding of Mars has been identified by several previous groups who were charged with creating a strategy for Mars exploration (e.g., COMPLEX, MarSWG, Planetary Roadmap Team). This is a so-called "network" mission, which places a large number of science platforms simultaneously on the surface.

W. B. Banerdt↗
NASA NTRS2002

STS-111 Crew Interviews: Paul Lockhart, Pilot

STS-111 Pilot Paul Lockhart is seen during this preflight interview, where he gives a quick overview of the mission before answering questions about his inspiration to become an astronaut and his career path. He discusses the following mission goals: the crew transfer activities (the Expedition 5 crew is replacing the Expedition 4 crew on the International Space Station (ISS)), the delivery of the payloads which includes the Mobile Remote Servicer Base System (MBS), and the planned extravehicular activities (EVAs) which include attaching the MBS to the ISS and repairing the station's robot arm. He describes in-flight procedures for launch, reentry and docking with the ISS. He ends with his thoughts on the role of international cooperation in building and maintaining ISS.

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NASA NTRS2003

Dissociative Ionization of Aromatic and Heterocyclic Molecules

Space radiation poses a major health hazard to humans in space flight. The high-energy charged particles in space radiation ranging from protons to high atomic number, high-energy (HZE) particles, and the secondary species they produce, attack DNA, cells, and tissues. Of the potential hazards, long-term health effects such as carcinogenesis are likely linked to the DNA lesions caused by secondary electrons in the 1 - 30 eV range. Dissociative ionization (DI) is one of the electron collision processes that can damage the DNA, either directly by causing a DNA lesion, or indirectly by producing radicals and cations that attack the DNA. To understand this process, we have developed a theoretical model for DI. Our model makes use of the fact that electron motion is much faster than nuclear motion and assumes DI proceeds through a two-step process. The first step is electron-impact ionization resulting in a particular state of the molecular ion in the geometry of the neutral molecule. In the second step the ion undergoes unimolecular dissociation. Thus the DI cross section sigma(sup DI)(sub a) for channel a is given by sigma(sup DI)(sub a) = sigma(sup I)(sub a) P(sub D) with sigma(sup I)(sub a) the ionization cross section of channel a and P(sub D) the dissociation probability. This model has been applied to study the DI of H2O, NH3, and CH4, with results in good agreement with experiment. The ionization cross section sigma(sup I)(sub a) was calculated using the improved binary encounter-dipole model and the unimolecular dissociation probability P(sub D) obtained by following the minimum energy path determined by the gradients and Hessians of the electronic energy with respect to the nuclear coordinates of the ion. This model is used to study the DI from the low-lying channels of benzene and pyridine to understand the different product formation in aromatic and heterocyclic molecules. DI study of the DNA base thymine is underway. Solvent effects will also be discussed.

Huo, Winifred M.↗
NASA NTRS2012

Multiscale Modeling of Structurally-Graded Materials Using Discrete Dislocation Plasticity Models and Continuum Crystal Plasticity Models

A multiscale modeling methodology that combines the predictive capability of discrete dislocation plasticity and the computational efficiency of continuum crystal plasticity is developed. Single crystal configurations of different grain sizes modeled with periodic boundary conditions are analyzed using discrete dislocation plasticity (DD) to obtain grain size-dependent stress-strain predictions. These relationships are mapped into crystal plasticity parameters to develop a multiscale DD/CP model for continuum level simulations. A polycrystal model of a structurally-graded microstructure is developed, analyzed and used as a benchmark for comparison between the multiscale DD/CP model and the DD predictions. The multiscale DD/CP model follows the DD predictions closely up to an initial peak stress and then follows a strain hardening path that is parallel but somewhat offset from the DD predictions. The difference is believed to be from a combination of the strain rate in the DD simulation and the inability of the DD/CP model to represent non-monotonic material response.

Saether, Erik↗
NASA NTRS2013

NASA's Space Launch System: Moving Toward the Launch Pad

The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for human space flight and scientific missions beyond Earth orbit. Developed with the goals of safety, affordability, and sustainability in mind, the SLS rocket will launch the Orion Multi-Purpose Crew Vehicle (MPCV), equipment, supplies, and major science missions for exploration and discovery. Supporting Orion's first autonomous flight to lunar orbit and back in 2017 and its first crewed flight in 2021, the SLS will evolve into the most powerful launch vehicle ever flown, via an upgrade approach that will provide building blocks for future space exploration and development. NASA is working to develop this new capability in an austere economic climate, a fact which has inspired the SLS team to find innovative solutions to the challenges of designing, developing, fielding, and operating the largest rocket in history. This paper will summarize the planned capabilities of the vehicle, the progress the SLS program has made in the 2 years since the Agency formally announced its architecture in September 2011, and the path the program is following to reach the launch pad in 2017 and then to evolve the 70 metric ton (t) initial lift capability to 130-t lift capability. The paper will explain how, to meet the challenge of a flat funding curve, an architecture was chosen which combines the use and enhancement of legacy systems and technology with strategic new development projects that will evolve the capabilities of the launch vehicle. This approach reduces the time and cost of delivering the initial 70 t Block 1 vehicle, and reduces the number of parallel development investments required to deliver the evolved version of the vehicle. The paper will outline the milestones the program has already reached, from developmental milestones such as the manufacture of the first flight hardware and the record-breaking testing of the J-2X engine, to life-cycle milestones such as the vehicle's Preliminary Design Review. The paper will also discuss the remaining challenges in both delivering the 70 t vehicle and in evolving its capabilities to the 130 t vehicle, and how the program plans to accomplish these goals. As this paper will explain, SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by harnessing business and technological innovations to deliver sustainable solutions for space exploration

Creech, Stephen D.↗
NASA NTRS2014

NASA's Space Launch System: An Enabling Capability for Discovery

The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for human spaceflight and scientific missions beyond Earth orbit. Developed with the goals of safety, affordability, and sustainability in mind, the SLS rocket will launch the Orion Multi-Purpose Crew Vehicle (MPCV), equipment, supplies, and major science missions for exploration and discovery. Making its first uncrewed test flight in 2017 and its first crewed flight in 2021, the SLS will evolve into the most powerful launch vehicle ever flown, capable of supporting human missions into deep space and to Mars. This paper will summarize the planned capabilities of the vehicle, the progress the SLS Program has made in the years since the Agency formally announced its architecture in September 2011, and the path the program is following to reach the launch pad in 2017 and then to evolve the 70 metric ton (t) initial lift capability to 130 t lift capability. The paper will outline the milestones the program has already reached, from developmental milestones such as the manufacture of the first flight hardware and recordbreaking engine testing, to life-cycle milestones such as the vehicle's Preliminary Design Review in the summer of 2013. The paper will also discuss the remaining challenges in both delivering the 70 t vehicle and in evolving its capabilities to the 130 t vehicle, and how the program plans to accomplish these goals. In addition, this paper will demonstrate how the Space Launch System is being designed to enable or enhance not only human exploration missions, but robotic scientific missions as well. Because of its unique launch capabilities, SLS will support simplifying spacecraft complexity, provide improved mass margins and radiation mitigation, and reduce mission durations. These capabilities offer attractive advantages for ambitious science missions by reducing infrastructure requirements, cost, and schedule. A traditional baseline approach for a mission to investigate the Jovian system would require a complicated trajectory with several gravity-assist planetary fly-bys to achieve the necessary outbound velocity. The SLS rocket, offering significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, providing scientific results sooner and at lower operational cost. The SLS rocket will launch payloads of unprecedented mass and volume, such as "monolithic" telescopes and in-space infrastructure, and will revolutionize science mission planning and design for years to come. As this paper will explain, SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by harnessing business and technological innovations to deliver sustainable solutions for space exploration.

Creech, Stephen D.↗
NASA NTRS2014

NASA's Space Launch System: An Enabling Capability for Discovery

The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for human spaceflight and scientific missions beyond Earth orbit. Developed with the goals of safety, affordability, and sustainability in mind, the SLS rocket will launch the Orion Multi-Purpose Crew Vehicle (MPCV), equipment, supplies, and major science missions for exploration and discovery. Making its first uncrewed test flight in 2017 and its first crewed flight in 2021, the SLS will evolve into the most powerful launch vehicle ever flown, capable of supporting human missions into deep space and to Mars. This paper will summarize the planned capabilities of the vehicle, the progress the SLS Program has made in the years since the Agency formally announced its architecture in September 2011, and the path the program is following to reach the launch pad in 2017 and then to evolve the 70 metric ton (t) initial lift capability to 130 t lift capability. The paper will outline the milestones the program has already reached, from developmental milestones such as the manufacture of the first flight hardware and recordbreaking engine testing, to life-cycle milestones such as the vehicle's Preliminary Design Review in the summer of 2013. The paper will also discuss the remaining challenges in both delivering the 70 t vehicle and in evolving its capabilities to the 130 t vehicle, and how the program plans to accomplish these goals. In addition, this paper will demonstrate how the Space Launch System is being designed to enable or enhance not only human exploration missions, but robotic scientific missions as well. Because of its unique launch capabilities, SLS will support simplifying spacecraft complexity, provide improved mass margins and radiation mitigation, and reduce mission durations. These capabilities offer attractive advantages for ambitious science missions by reducing infrastructure requirements, cost, and schedule. A traditional baseline approach for a mission to investigate the Jovian system would require a complicated trajectory with several gravity-assist planetary fly-bys to achieve the necessary outbound velocity. The SLS rocket, offering significantly higher C3 energies, can more quickly and effectively take the mission directly to its destination, providing scientific results sooner and at lower operational cost. The SLS rocket will launch payloads of unprecedented mass and volume, such as "monolithic" telescopes and in-space infrastructure, and will revolutionize science mission planning and design for years to come. As this paper will explain, SLS is making measurable progress toward becoming a global infrastructure asset for robotic and human scouts of all nations by harnessing business and technological innovations to deliver sustainable solutions for space exploration.

Creech, Stephen D.↗
NASA NTRS2016

In-Process Thermal Imaging of the Electron Beam Freeform Fabrication Process

Researchers at NASA Langley Research Center have been developing the Electron Beam Freeform Fabrication (EBF3) metal additive manufacturing process for the past 15 years. In this process, an electron beam is used as a heat source to create a small molten pool on a substrate into which wire is fed. The electron beam and wire feed assembly are translated with respect to the substrate to follow a predetermined tool path. This process is repeated in a layer-wise fashion to fabricate metal structural components. In-process imaging has been integrated into the EBF3 system using a near-infrared (NIR) camera. The images are processed to provide thermal and spatial measurements that have been incorporated into a closed-loop control system to maintain consistent thermal conditions throughout the build. Other information in the thermal images is being used to assess quality in real time by detecting flaws in prior layers of the deposit. NIR camera incorporation into the system has improved the consistency of the deposited material and provides the potential for real-time flaw detection which, ultimately, could lead to the manufacture of better, more reliable components using this additive manufacturing process.

Taminger, Karen M.↗
NASA NTRS2015

Resource Prospector (RP): A Cost-Effective Lunar Resource Pathfinder

Resource Prospector (RP) is an in-situ resource utilization (ISRU) technology demonstration mission under study by the NASA Human Exploration and Operations Mission Directorates (HEOMD). This clever mission is currently planned to launch in 2020 and will demonstrate extraction of oxygen, water and other volatiles, as well measure mineralogical content such as silicon and light metals, like aluminum and titanium, from lunar regolith. Expanding human presence beyond low-Earth orbit to asteroids and Mars will require the maximum possible use of local materials, so-called in-situ resources, and the moon presents a unique destination to conduct robotic investigations that advance ISRU capabilities, as well as providing significant exploration and science value. This mission is equally important; however, for how it executes as a risk-tolerant, cost-effective mission. RP follows on the path-finding approaches of the Lunar Crater Observation and Sensing Satellite (LCROSS) mission. The LCROSS mission confirmed the presence of water-ice on the moon, but also established a new lightweight-approach to project and mission execution which was considerably cheaper and faster than traditional NASA missions. RP has been designated as a Class D mission, just as LCROSS. This mission classification is the most risk-tolerant class of mission within the NASA risk framework and as such, is given more latitude to accept higher-levels of residual risk. The intention is that by saving monies normally spent attempting to assure a single missions success, more missions can be funded. A well-designed portfolio can accept occasional mission failure, as it still gets more done for the same investment of resources. This classification enables tailoring the NASA Policy Requirements (NPRs) to lighter-weight approaches to mission management and execution. RP is also studying both international and commercial partnerships as a means to maximize return on the investment. International partnerships provide both capabilities synergies and cost-sharing opportunities, while the evolving new space commercial options are revealing new approaches to acquiring cost-effective services, including the benefits of bundling services. Even the world of launch vehicles is changing, offering much less expensive access to space, especially if NASA is able to be flexible in how it approaches mission assurance. Finally, leveraging investments being made elsewhere within a program portfolio, can enable cost-savings by enabling two applications with one investment. RP will be the next pathfinder mission to both enable exploration capabilities for future missions, and continue to evolve cost-effective approaches for NASA.

Lunar↗
NASA NTRSDate not supplied

Trajectory Generation for Distributed Electric Propulsion Vehicles with Propeller Synchronization

In this paper, we propose a method for generating dynamically feasible trajectories for an acoustically aware vehicle with propeller phase control. The trajectory generation procedure allows both propeller phase control and navigation objectives to be considered simultaneously. The presented method is demonstrated where the mission objectives are given as a desired position and phase trajectory. From these trajectories, the full desired state of the vehicle is calculated. Furthermore, the control inputs that realize the desired mission objectives are computed. The acoustic performance for the given trajectory is estimated in terms of sound pressure level as a function of tracking performance. The method is demonstrated in simulation, where the vehicle must navigate through an urban environment with both spatial and acoustic constraints. In the presented scenario, the vehicle must follow a given flight path, and can only reduce sound pressure level by changing the propeller phase targets.

acoustically-aware vehicle↗