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Sample records for augmented propulsion experiment

  1. Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Cole, John; Lineberry, John; Chapman, Jim; Schmidt, Harold; Cook, Stephen (Technical Monitor)

    2002-01-01

    A fundamental obstacle to routine space access is the specific energy limitations associated with chemical fuels. In the case of vertical take-off, the high thrust needed for vertical liftoff and acceleration to orbit translates into power levels in the 10 GW range. Furthermore, useful payload mass fractions are possible only if the exhaust particle energy (i.e., exhaust velocity) is much greater than that available with traditional chemical propulsion. The electronic binding energy released by the best chemical reactions (e.g., LOX/LH2 for example, is less than 2 eV per product molecule (approx. 1.8 eV per H2O molecule), which translates into particle velocities less than 5 km/s. Useful payload fractions, however, will require exhaust velocities exceeding 15 km/s (i.e., particle energies greater than 20 eV). As an added challenge, the envisioned hypothetical RLV (reusable launch vehicle) should accomplish these amazing performance feats while providing relatively low acceleration levels to orbit (2-3g maximum). From such fundamental considerations, it is painfully obvious that planned and current RLV solutions based on chemical fuels alone represent only a temporary solution and can only result in minor gains, at best. What is truly needed is a revolutionary approach that will dramatically reduce the amount of fuel and size of the launch vehicle. This implies the need for new compact high-power energy sources as well as advanced accelerator technologies for increasing engine exhaust velocity. Electromagnetic acceleration techniques are of immense interest since they can be used to circumvent the thermal limits associated with conventional propulsion systems. This paper describes the Magnetohydrodynamic Augmented Propulsion Experiment (MAPX) being undertaken at NASA Marshall Space Flight Center (MSFC). In this experiment, a 1-MW arc heater is being used as a feeder for a 1-MW magnetohydrodynamic (MHD) accelerator. The purpose of the experiment is to demonstrate

  2. Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Cole, John; Lineberry, John; Chapman, Jim; Schmidt, Harold; Cook, Stephen (Technical Monitor)

    2002-01-01

    A fundamental obstacle to routine space access is the specific energy limitations associated with chemical fuels. In the case of vertical take-off, the high thrust needed for vertical liftoff and acceleration to orbit translates into power levels in the 10 GW range. Furthermore, useful payload mass fractions are possible only if the exhaust particle energy (i.e., exhaust velocity) is much greater than that available with traditional chemical propulsion. The electronic binding energy released by the best chemical reactions (e.g., LOX/LH2 for example, is less than 2 eV per product molecule (approx. 1.8 eV per H2O molecule), which translates into particle velocities less than 5 km/s. Useful payload fractions, however, will require exhaust velocities exceeding 15 km/s (i.e., particle energies greater than 20 eV). As an added challenge, the envisioned hypothetical RLV (reusable launch vehicle) should accomplish these amazing performance feats while providing relatively low acceleration levels to orbit (2-3g maximum). From such fundamental considerations, it is painfully obvious that planned and current RLV solutions based on chemical fuels alone represent only a temporary solution and can only result in minor gains, at best. What is truly needed is a revolutionary approach that will dramatically reduce the amount of fuel and size of the launch vehicle. This implies the need for new compact high-power energy sources as well as advanced accelerator technologies for increasing engine exhaust velocity. Electromagnetic acceleration techniques are of immense interest since they can be used to circumvent the thermal limits associated with conventional propulsion systems. This paper describes the Magnetohydrodynamic Augmented Propulsion Experiment (MAPX) being undertaken at NASA Marshall Space Flight Center (MSFC). In this experiment, a 1-MW arc heater is being used as a feeder for a 1-MW magnetohydrodynamic (MHD) accelerator. The purpose of the experiment is to demonstrate

  3. Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.

    2008-01-01

    Over the past several years, efforts have been under way to design and develop an operationally flexible research facility for investigating the use of cross-field MHD accelerators as a potential thrust augmentation device for thermal propulsion systems. The baseline configuration for this high-power experimental facility utilizes a 1.5-MWe multi-gas arc-heater as a thermal driver for a 2-MWe MHD accelerator, which resides in a large-bore 2-tesla electromagnet. A preliminary design study using NaK seeded nitrogen as the working fluid led to an externally diagonalized segmented MHD channel configuration based on an expendable heat-sink design concept. The current status report includes a review of engineering/design work and performance optimization analyses and summarizes component hardware fabrication and development efforts, preliminary testing results, and recent progress toward full-up assembly and testing

  4. Status of Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Lineberry, John T.

    2007-01-01

    Over the past several years, efforts have been under way to design and develop an operationally flexible research facility for investigating the use of cross-field MHD accelerators as a potential thrust augmentation device for thermal propulsion systems, The baseline configuration for this high-power experimental facility utilizes a 1,5-MW, multi-gas arc-heater as a thermal driver for a 2-MW, MHD accelerator, which resides in a large-bore 2-tesla electromagnet. A preliminary design study using NaK seeded nitrogen as the working fluid led to an externally diagonalized segmented MHD channel configuration based on an expendable beat-sink design concept. The current status report includes a review of engineering/design work and performance optimization analyses and summarizes component hardware fabrication and development efforts, preliminary testing results, and recent progress toward full-up assembly and testing

  5. Magnetohydrodynamic Augmented Propulsion Experiment: I. Performance Analysis and Design

    NASA Technical Reports Server (NTRS)

    Litchford, R. J.; Cole, J. W.; Lineberry, J. T.; Chapman, J. N.; Schmidt, H. J.; Lineberry, C. W.

    2003-01-01

    The performance of conventional thermal propulsion systems is fundamentally constrained by the specific energy limitations associated with chemical fuels and the thermal limits of available materials. Electromagnetic thrust augmentation represents one intriguing possibility for improving the fuel composition of thermal propulsion systems, thereby increasing overall specific energy characteristics; however, realization of such a system requires an extremely high-energy-density electrical power source as well as an efficient plasma acceleration device. This Technical Publication describes the development of an experimental research facility for investigating the use of cross-field magnetohydrodynamic (MHD) accelerators as a possible thrust augmentation device for thermal propulsion systems. In this experiment,a 1.5-MW(sub e) Aerotherm arc heater is used to drive a 2-MW(sub e) MHD accelerator. The heatsink MHD accelerator is configured as an externally diagonalized, segmented channel, which is inserted into a large-bore, 2-T electromagnet. The performance analysis and engineering design of the flow path are described as well as the parameter measurements and flow diagnostics planned for the initial series of test runs.

  6. Three-Dimensional Numerical Modeling of Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Turner, M. W.; Hawk, C. W.; Litchford, R. J.

    2009-01-01

    Over the past several years, NASA Marshall Space Flight Center has engaged in the design and development of an experimental research facility to investigate the use of diagonalized crossed-field magnetohydrodynamic (MHD) accelerators as a possible thrust augmentation device for thermal propulsion systems. In support of this effort, a three-dimensional numerical MHD model has been developed for the purpose of analyzing and optimizing accelerator performance and to aid in understanding critical underlying physical processes and nonideal effects. This Technical Memorandum fully summarizes model development efforts and presents the results of pretest performance optimization analyses. These results indicate that the MHD accelerator should utilize a 45deg diagonalization angle with the applied current evenly distributed over the first five inlet electrode pairs. When powered at 100 A, this configuration is expected to yield a 50% global efficiency with an 80% increase in axial velocity and a 50% increase in centerline total pressure.

  7. Radiation Augmented Propulsion Feasibility.

    DTIC Science & Technology

    1985-12-01

    FE 1~ 1986 December 1985 Authors: Rockwell International S . C. Hurlock Rocketdyne Division V. Quan 6633 Canoga Ave ()J. Blauer Canoga Park, CA 91304 00...Organization Report Number( s ) RI /RD85-257 AFRPL-TR-85-068 Gam NAME OF PERFORMING ORGANIZATION b. OF FICE SY MBO L 7. NAME OF MONITORING ORGANIZATION...EW - PropulsionFeasibilityStudy_(U) ______ 12. PERSONAL AUTHOR( S ) Hurlock, S . C.; Quan, V.; Blauer, J.; Hall, J. R.; Wagner, R. I.; Wilson, R. 0. 113

  8. Tests on Thrust Augmenters for Jet Propulsion

    NASA Technical Reports Server (NTRS)

    Jacobs, Eastman N; Shoemaker, James M

    1932-01-01

    This series of tests was undertaken to determine how much the reaction thrust of a jet could be increased by the use of thrust augmenters and thus to give some indication as to the feasibility of jet propulsion for airplanes. The tests were made during the first part of 1927 at the Langley Memorial Aeronautical Laboratory. A compressed air jet was used in connection with a series of annular guides surrounding the jet to act as thrust augmenters. The results show that, although it is possible to increase the thrust of a jet, the increase is not large enough to affect greatly the status of the problem of the application of jet propulsion to airplanes.

  9. Propulsion IVHM Technology Experiment

    NASA Technical Reports Server (NTRS)

    Chicatelli, Amy K.; Maul, William A.; Fulton, Christopher E.

    2006-01-01

    The Propulsion IVHM Technology Experiment (PITEX) successfully demonstrated real-time fault detection and isolation of a virtual reusable launch vehicle (RLV) main propulsion system (MPS). Specifically, the PITEX research project developed and applied a model-based diagnostic system for the MPS of the X-34 RLV, a space-launch technology demonstrator. The demonstration was simulation-based using detailed models of the propulsion subsystem to generate nominal and failure scenarios during captive carry, which is the most safety-critical portion of the X-34 flight. Since no system-level testing of the X-34 Main Propulsion System (MPS) was performed, these simulated data were used to verify and validate the software system. Advanced diagnostic and signal processing algorithms were developed and tested in real time on flight-like hardware. In an attempt to expose potential performance problems, the PITEX diagnostic system was subjected to numerous realistic effects in the simulated data including noise, sensor resolution, command/valve talkback information, and nominal build variations. In all cases, the PITEX system performed as required. The research demonstrated potential benefits of model-based diagnostics, defined performance metrics required to evaluate the diagnostic system, and studied the impact of real-world challenges encountered when monitoring propulsion subsystems.

  10. Augmentation of Rocket Propulsion: Physical Limits

    NASA Technical Reports Server (NTRS)

    Taylor, Charles R.

    1996-01-01

    Rocket propulsion is not ideal when the propellant is not ejected at a unique velocity in an inertial frame. An ideal velocity distribution requires that the exhaust velocity vary linearly with the velocity of the vehicle in an inertial frame. It also requires that the velocity distribution variance as a thermodynamic quantity be minimized. A rocket vehicle with an inert propellant is not optimal, because it does not take advantage of the propellant mass for energy storage. Nor is it logical to provide another energy storage device in order to realize variable exhaust velocity, because it would have to be partly unfilled at the beginning of the mission. Performance is enhanced by pushing on the surrounding because it increases the reaction mass and decreases the reaction jet velocity. This decreases the fraction of the energy taken away by the propellant and increases the share taken by the payload. For an optimal model with the propellant used as fuel, the augmentation realized by pushing on air is greatest for vehicles with a low initial/final mass ratio. For a typical vehicle in the Earth's atmosphere, the augmentation is seen mainly at altitudes below about 80 km. When drag is taken into account, there is a well-defined optimum size for the air intake. Pushing on air has the potential to increase the performance of rockets which pass through the atmosphere. This is apart from benefits derived from "air breathing", or using the oxygen in the atmosphere to reduce the mass of an on-board oxidizer. Because of the potential of these measures, it is vital to model these effects more carefully and explore technology that may realize their advantages.

  11. Gasdynamic Mirror Fusion Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    Nuclear fusion appears to be the most promising concept for producing extremely high specific impulse rocket engines. One particular fusion concept which seems to be particularly well suited for fusion propulsion applications is the gasdynamic mirror (GDM). This device would operate at much higher plasma densities and with much larger LD ratios than previous mirror machines. Several advantages accrue from such a design. First, the high LA:) ratio minimizes to a large extent certain magnetic curvature effects which lead to plasma instabilities causing a loss of plasma confinement. Second, the high plasma density will result in the plasma behaving much more Re a conventional fluid with a mean free path shorter than the length of the device. This characteristic helps reduce problems associated with "loss cone" microinstabilities. An experimental GDM device is currently being constructed at the NASA Marshall Space Flight Center to provide an initial assessment of the feasibility of this type of propulsion system. Initial experiments are expected to commence in the late fall of 2000.

  12. Planned In-Space Electric Propulsion Experiments

    NASA Technical Reports Server (NTRS)

    Stocky, John

    1994-01-01

    Ion Propulsion provides an order of magnitude improvement, relative to chemical on-board propulsion systems, of specific impulse at the cost of a relatively small increase in propulsion system dry mass. For civilian space craft, ion propulsion technology provides the potential for increased performance and reduced cost for planetary spacecraft and for large satellites in geostationary orbit. For military applications ion propulsion offers significant benefits for station keeping and repositioning satellites in geostationary orbit. NASA has begun to validate ion propulsion technology for applications to which 2.5 kW to 5.0 kW ion thrusters would be appropriate. NASA's validation program, called NSTAR (NASA SEP Technology Application Readiness), consists of two major elements: a ground test element and an in-space experiment. The Ground Test Element will validate the life, integrability, and performance of low-power ion propulsion. The In-Space Element will demonstrate the ability to integrate and fly an ion propulsion system. As an experiment, it will measure the interactions between the ion propulsion system, the host spacecraft, and the surrounding space plasma; and it will provide a quantitative assessment of the ability of ground testing to replicate the in-space performance of ion thrusters. By involving industry in this program, a commercial source for this technology will be assured. Further, the successful completion of the NSTAR validation program will stimulate commercial and government (both civilian and military) uses of this technology.

  13. US in-space electric propulsion experiments

    NASA Technical Reports Server (NTRS)

    Stocky, John F.; Vondra, Robert; Sutton, Alan M.

    1995-01-01

    Arcjet and ion propulsion offer potentially significant reductions in the mass of propulsion systems required for Earth orbiting satellites and planetary spacecraft. For this reason, they have been the subject of validation and demonstration programs. After examining the benefits of electric propulsion, this paper discusses the technology base for the Electric Propulsion Space Experiment (ESEX) arcjet demonstration experiment and the NASA Technology Application Readiness (NSTAR) ion propulsion validation program. As part of the Advanced Research Global Observation Spacecraft (ARGOS), ESEX will perform ten 15-min firings of a 30-kW ammonia arcjet. NASA's validation program, NSTAR, consists of two major elements: a ground-test element and an in-space experiment. The ground element will validate the life, integrability, and performance of low-power ion propulsion. The in-space element will demonstrate the feasibility of integrating and flying an ion propulsion system. The experiment will measure the interactions among the ion propulsion system, the host spacecraft, and the surrounding space plasma. It will provide a quantitative assessment of the ability of ground testing to replicate the in-space performance ion thrusters. By involving industry in NSTAR, a commercial source for this technology will be ensured. Furthermore, the successful completion of the NSTAR validation program will stimulate commercial and government (both civilian and military) uses of this technology.

  14. US in-space electric propulsion experiments

    NASA Astrophysics Data System (ADS)

    Stocky, John F.; Vondra, Robert; Sutton, Alan M.

    1995-03-01

    Arcjet and ion propulsion offer potentially significant reductions in the mass of propulsion systems required for Earth orbiting satellites and planetary spacecraft. For this reason, they have been the subject of validation and demonstration programs. After examining the benefits of electric propulsion, this paper discusses the technology base for the Electric Propulsion Space Experiment (ESEX) arcjet demonstration experiment and the NASA Technology Application Readiness (NSTAR) ion propulsion validation program. As part of the Advanced Research Global Observation Spacecraft (ARGOS), ESEX will perform ten 15-min firings of a 30-kW ammonia arcjet. NASA's validation program, NSTAR, consists of two major elements: a ground-test element and an in-space experiment. The ground element will validate the life, integrability, and performance of low-power ion propulsion. The in-space element will demonstrate the feasibility of integrating and flying an ion propulsion system. The experiment will measure the interactions among the ion propulsion system, the host spacecraft, and the surrounding space plasma. It will provide a quantitative assessment of the ability of ground testing to replicate the in-space performance ion thrusters. By involving industry in NSTAR, a commercial source for this technology will be ensured. Furthermore, the successful completion of the NSTAR validation program will stimulate commercial and government (both civilian and military) uses of this technology.

  15. Gasdynamic Mirror (GDM) Fusion Propulsion Engine Experiment

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The Gasdynamic Mirror, or GDM, is an example of a magnetic mirror-based fusion propulsion system. Its design is primarily consisting of a long slender solenoid surrounding a vacuum chamber that contains plasma. The bulk of the fusion plasma is confined by magnetic field generated by a series of toroidal-shaped magnets in the center section of the device. the purpose of the GDM Fusion Propulsion Experiment is to confirm the feasibility of the concept and to demonstrate many of the operational characteristics of a full-size plasma can be confined within the desired physical configuration and still reman stable. This image shows an engineer from Propulsion Research Technologies Division at Marshall Space Flight Center inspecting solenoid magnets-A, an integrate part of the Gasdynamic Mirror Fusion Propulsion Engine Experiment.

  16. Gasdynamic Mirror (GDM) Fusion Propulsion Engine Experiment

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The Gasdynamic Mirror, or GDM, is an example of a magnetic mirror-based fusion propulsion system. Its design is primarily consisting of a long slender solenoid surrounding a vacuum chamber that contains plasma. The bulk of the fusion plasma is confined by magnetic field generated by a series of toroidal-shaped magnets in the center section of the device. the purpose of the GDM Fusion Propulsion Experiment is to confirm the feasibility of the concept and to demonstrate many of the operational characteristics of a full-size plasma can be confined within the desired physical configuration and still reman stable. This image shows an engineer from Propulsion Research Technologies Division at Marshall Space Flight Center inspecting solenoid magnets-A, an integrate part of the Gasdynamic Mirror Fusion Propulsion Engine Experiment.

  17. Jet Propulsion with Special Reference to Thrust Augmenters

    NASA Technical Reports Server (NTRS)

    Schubauer, G B

    1933-01-01

    An investigation of the possibility of using thrust augmented jets as prime movers was carried out. The augmentation was to be effected by allowing the jet to mix with the surrounding air in the presence of bodies which deflect the air set in motion by the jet.

  18. The Propulsive Small Expendable Deployer System Experiment

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Estes, Robert D.; Lorenzini, Enrico; Martinez-Sanchez, Manual; Sanmartin, Juan

    1999-01-01

    Relatively short electrodynamic tethers can extract orbital energy to 'push' against a planetary magnetic field to achieve propulsion without the expenditure of propellant. The Propulsive Small Expendable Deployer System experiment will use the flight-proven Small Expendable Deployer System (SEDS) to deploy a 5 km bare copper tether from a Delta II upper stage to achieve approximately 0.4 N drag thrust, thus lowering the altitude of the stage. The experiment will use a predominantly 'bare' tether for current collection in lieu of the endmass collector and insulated tether approach used on previous missions. The flight experiment is a precursor to a more ambitious electrodynamic tether upper stage demonstration mission which will be capable of orbit raising, lowering and inclination changes - all using electrodynamic thrust. The expected performance of the tether propulsion system during the experiment is described.

  19. TROPIX: A solar electric propulsion flight experiment

    NASA Technical Reports Server (NTRS)

    Hickman, J. Mark; Hillard, G. Barry; Oleson, Steven R.

    1993-01-01

    The Transfer Orbit Plasma Interaction Experiment (TROPIX) is a proposed scientific experiment and flight demonstration of a solar electric propulsion vehicle. Its mission goals are to significantly increase our knowledge of Earth's magnetosphere and its associated plasma environment and to demonstrate an operational solar electric upper stage (SEUS) for small launch vehicles. The scientific investigations and flight demonstration technology experiments are uniquely interrelated because of the spacecraft's interaction with the surrounding environment. The data obtained will complement previous studies of the Earth's magnetosphere and space plasma environment by supplying the knowledge necessary to attain the strategic objectives of the NASA Office of Space Science. This first operational use of a primary ion propulsion vehicle, designed to withstand the harsh environments from low Earth orbit to geosynchronous Earth orbit, may lead to the development of a new class of electric propulsion upper stages or space-based transfer vehicles and may improve future spacecraft design and safety.

  20. Building a Propulsion Experiment Project Management Environment

    NASA Technical Reports Server (NTRS)

    Keiser, Ken; Tanner, Steve; Hatcher, Danny; Graves, Sara

    2004-01-01

    What do you get when you cross rocket scientists with computer geeks? It is an interactive, distributed computing web of tools and services providing a more productive environment for propulsion research and development. The Rocket Engine Advancement Program 2 (REAP2) project involves researchers at several institutions collaborating on propulsion experiments and modeling. In an effort to facilitate these collaborations among researchers at different locations and with different specializations, researchers at the Information Technology and Systems Center,' University of Alabama in Huntsville, are creating a prototype web-based interactive information system in support of propulsion research. This system, to be based on experience gained in creating similar systems for NASA Earth science field experiment campaigns such as the Convection and Moisture Experiments (CAMEX), will assist in the planning and analysis of model and experiment results across REAP2 participants. The initial version of the Propulsion Experiment Project Management Environment (PExPM) consists of a controlled-access web portal facilitating the drafting and sharing of working documents and publications. Interactive tools for building and searching an annotated bibliography of publications related to REAP2 research topics have been created to help organize and maintain the results of literature searches. Also work is underway, with some initial prototypes in place, for interactive project management tools allowing project managers to schedule experiment activities, track status and report on results. This paper describes current successes, plans, and expected challenges for this project.

  1. Operationally efficient propulsion system study (OEPSS) data book. Volume 10; Air Augmented Rocket Afterburning

    NASA Technical Reports Server (NTRS)

    Farhangi, Shahram; Trent, Donnie (Editor)

    1992-01-01

    A study was directed towards assessing viability and effectiveness of an air augmented ejector/rocket. Successful thrust augmentation could potentially reduce a multi-stage vehicle to a single stage-to-orbit vehicle (SSTO) and, thereby, eliminate the associated ground support facility infrastructure and ground processing required by the eliminated stage. The results of this preliminary study indicate that an air augmented ejector/rocket propulsion system is viable. However, uncertainties resulting from simplified approach and assumptions must be resolved by further investigations.

  2. Simplest magnetic propulsion experiment with liquid gallium

    NASA Astrophysics Data System (ADS)

    Zakharov, L. E.; Hoffman, D.; Taylor, J.

    2001-10-01

    Magnetic propulsion of liquid metal represents a new MHD effect (discovered in Dec. 1998) which allows to drive fast liquid metal (essentially, lithium) flow in the strong toroidal magnetic field. For the fusion research, it suggests a unique way of the power extraction from the tokamak-reactor chamber. Fast flowing liquid lithium can extract at least an order of magnitude more power than typically considered in the conventional concepts, (all oriented toward the divertor configurations). Importance of the problem of the power extraction recently became even more evident when the conventional reactor approach (after 25 years of existence and spending) spent almost 15 years on the ITER next step tokamak project and resulted in a 1 MW/m^2 of the power load on the first wall, too small for the any reasonable fusion reactor. In contrast to this, the power extraction capabilities of magnetic propulsion are fully consistent with the fusion reactor requirements or even exceeding them. The first experiment, which demonstrates the effect of magnetic propulsion has been developed in PPPL based on small coaxial propulsion cell with the magnetic field generated by the current through the cell. The device can work in both propulsion and the current limiting regime.

  3. Space Experiments to Advance Beamed Energy Propulsion

    NASA Astrophysics Data System (ADS)

    Johansen, Donald G.

    2010-05-01

    High power microwave sources are now available and usable, with modification, or beamed energy propulsion experiments in space. As output windows and vacuum seals are not needed space is a natural environment for high power vacuum tubes. Application to space therefore improves reliability and performance but complicates testing and qualification. Low power communications satellite devices (TWT, etc) have already been through the adapt-to-space design cycle and this history is a useful pathway for high power devices such as gyrotrons. In this paper, space experiments are described for low earth orbit (LEO) and lunar environment. These experiments are precursors to space application for beamed energy propulsion using high power microwaves. Power generation and storage using cryogenic systems are important elements of BEP systems and also have an important role as part of BEP experiments in the space environment.

  4. Experience with transumbilical breast augmentation.

    PubMed

    Sudarsky, L

    2001-05-01

    Transumbilical breast augmentation (TUBA), an endoscopicassisted procedure in which saline breast prostheses are inserted through the umbilicus, is a patient-driven, frequently performed procedure that remains controversial. The author describes the operative technique and results in 90 patients who underwent TUBA between October 1996 and July 2000 by the same surgeon in a community practice. A total of 85 patients underwent submammary TUBA and 5 patients underwent submuscular TUBA. Seventy patients were available for follow-up. Postoperative results of the 70 patients were graded as very good in 56 (80%), good in 12 (17%), and fair in 2 (2.9%). Complications were conversion to an open approach in 1 patient and an accidental submuscular entry into the pocket in 1 patient. There were four capsular contractures (5.7%), 5 patients (7.1%) were reoperated: 2 for capsulectomies, 1 for implant buckling, 1 for scar revision, and 1 for removal of the implants. There were no implant ruptures, hematomas, or infections. Advantages of TUBA include minimal scarring, remote incision, short operating time, low capsular contracture rate, and rapid recovery. These results of this evolving procedure suggest that in select patients TUBA provides a high level of patient satisfaction and low complication rates. As TUBA techniques for submuscular placement continue to develop, more patients may become TUBA candidates.

  5. Computational Analysis of Powered Lift Augmentation for the LEAPTech Distributed Electric Propulsion Wing

    NASA Technical Reports Server (NTRS)

    Deere, Karen A.; Viken, Sally A.; Carter, Melissa B.; Viken, Jeffrey K.; Wiese, Michael R.; Farr, Norma L.

    2017-01-01

    A computational study of a distributed electric propulsion wing with a 40deg flap deflection has been completed using FUN3D. Two lift-augmentation power conditions were compared with the power-off configuration on the high-lift wing (40deg flap) at a 73 mph freestream flow and for a range of angles of attack from -5 degrees to 14 degrees. The computational study also included investigating the benefit of corotating versus counter-rotating propeller spin direction to powered-lift performance. The results indicate a large benefit in lift coefficient, over the entire range of angle of attack studied, by using corotating propellers that all spin counter to the wingtip vortex. For the landing condition, 73 mph, the unpowered 40deg flap configuration achieved a maximum lift coefficient of 2.3. With high-lift blowing the maximum lift coefficient increased to 5.61. Therefore, the lift augmentation is a factor of 2.4. Taking advantage of the fullspan lift augmentation at similar performance means that a wing powered with the distributed electric propulsion system requires only 42 percent of the wing area of the unpowered wing. This technology will allow wings to be 'cruise optimized', meaning that they will be able to fly closer to maximum lift over drag conditions at the design cruise speed of the aircraft.

  6. [Experiences with the augmentation of vocal cords].

    PubMed

    Berghaus, A

    1987-06-01

    Augmentation of a vocal fold serves to improve glottic closure and may be indicated for paresis of the recurrent nerve and after tumor resection. Methods include injection of viscous fluids (paraffin, liquid silicone, polyvinyl alcohol, gelatin, sesame oil, collagen and particularly teflon paste) and operations to tighten the vocal cord or displace it medially. The disadvantages of the former include the danger of overcorrection, tissue irritation and possible systemic absorption of the material. As an alternative, solid material such as cartilage or synthetics may be used for augmentation. Experience obtained so far has shown that chips of porous polyethylene (PHDPE) are particularly suitable: they are easy to use, show good tissue tolerance and are anchored by ingrowth of connective tissue. The value of photokymography of the larynx in the assessment of therapeutic results after vocal-fold augmentation is discussed.

  7. Electric propulsion flight experience and technology readiness

    NASA Astrophysics Data System (ADS)

    Pollard, J. E.; Jackson, D. E.; Marvin, D. C.; Jenkin, A. B.; Janson, S. W.

    1993-06-01

    Spacecraft electric propulsion technology is reviewed here to provide mission planners and potential users with a better appreciation of its capabilities and limitations. Flight experience provides the best measure of EP technology readiness. We describe and document the flight history and development status of EP in domestic, foreign, and commercial programs. Low-power resistojets, arcjets, ion engines, and plasma thrusters are applicable today for stationkeeping and drag compensation. Future high-power systems would enable large velocity-change maneuvers. The trade-space of EP encompasses significant performance benefits (reduced propellant mass, enhanced payload, system-level synergism), along with challenges (hardware development, system operations, non-technical issues). The choice of design parameters (thrust, specific impulse, input power) depends on how much of a change from traditional spacecraft operations is acceptable for a given mission - greater change will yield a greater payoff.

  8. Electric Propulsion Experiment (EPEX) onboard Space Flyer Unit (SFU)

    NASA Astrophysics Data System (ADS)

    Toki, Kyoichiro; Shimizu, Yukio; Kuriki, Kyoichi; Suzuki, Hiroshi; Kunii, Yoshinori

    The EPEX (Electric Propulsion Experiment) is a space test of an Magnetoplasmadynamic (MPD) propulsion system onboard the Space Flyer Unit - Mission One (SFU-1) scheduled in 1994. This is virtually the first test for the use of MPD arcjet as a thruster system with satisfactory electrical power of 430 W. The MPD propulsion in this country has keen interested on the pulsed quasi-steady thruster system with hydrazine (N2H4) propellant. This philosophy arises from the common use of conventional rocket propellants along with electric propulsion.

  9. A Revolutionary Lunar Space Transportation System Architecture Using Extraterrestrial Lox-augmented NTR Propulsion

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; Corban, Robert R.; Culver, Donald W.; Bulman, Melvin J.; Mcilwain, Mel C.

    1994-01-01

    The concept of a liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) engine is introduced, and its potential for revolutionizing lunar space transportation system (LTS) performance using extraterrestrial 'lunar-derived' liquid oxygen (LUNOX) is outlined. The LOX-augmented NTR (LANTR) represents the marriage of conventional liquid hydrogen (LH2)-cooled NTR and airbreathing engine technologies. The large divergent section of the NTR nozzle functions as an 'afterburner' into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the NTR's choked sonic throat: 'scramjet propulsion in reverse.' By varying the oxygen-to-fuel mixture ratio (MR), the LANTR concept can provide variable thrust and specific impulse (Isp) capability with a LH2-cooled NTR operating at relatively constant power output. For example, at a MR = 3, the thrust per engine can be increased by a factor of 2.75 while the Isp decreases by only 30 percent. With this thrust augmentation option, smaller, 'easier to develop' NTR's become more acceptable from a mission performance standpoint (e.g., earth escape gravity losses are reduced and perigee propulsion requirements are eliminated). Hydrogen mass and volume is also reduced resulting in smaller space vehicles. An evolutionary NTR-based lunar architecture requiring only Shuttle C and/or 'in-line' shuttle-derived launch vehicles (SDV's) would operate initially in an 'expandable mode' with NTR lunar transfer vehicles (LTV's) delivering 80 percent more payload on piloted missions than their LOX/LH2 chemical propulsion counterparts. With the establishment of LUNOX production facilities on the lunar surface and 'fuel/oxidizer' depot in low lunar orbit (LLO), monopropellant NTR's would be outfitted with an oxygen propellant module, feed system, and afterburner nozzle for 'bipropellant' operation. The LANTR cislunar LTV now transitions to a reusable mode with smaller vehicle and payload doubling benefits on

  10. A revolutionary lunar space transportation system architecture using extraterrestrial LOX-augmented NTR propulsion

    NASA Astrophysics Data System (ADS)

    Borowski, Stanley K.; Corban, Robert R.; Culver, Donald W.; Bulman, Melvin J.; McIlwain, Mel C.

    1994-08-01

    The concept of a liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) engine is introduced, and its potential for revolutionizing lunar space transportation system (LTS) performance using extraterrestrial 'lunar-derived' liquid oxygen (LUNOX) is outlined. The LOX-augmented NTR (LANTR) represents the marriage of conventional liquid hydrogen (LH2)-cooled NTR and airbreathing engine technologies. The large divergent section of the NTR nozzle functions as an 'afterburner' into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the NTR's choked sonic throat: 'scramjet propulsion in reverse.' By varying the oxygen-to-fuel mixture ratio (MR), the LANTR concept can provide variable thrust and specific impulse (Isp) capability with a LH2-cooled NTR operating at relatively constant power output. For example, at a MR = 3, the thrust per engine can be increased by a factor of 2.75 while the Isp decreases by only 30 percent. With this thrust augmentation option, smaller, 'easier to develop' NTR's become more acceptable from a mission performance standpoint (e.g., earth escape gravity losses are reduced and perigee propulsion requirements are eliminated). Hydrogen mass and volume is also reduced resulting in smaller space vehicles. An evolutionary NTR-based lunar architecture requiring only Shuttle C and/or 'in-line' shuttle-derived launch vehicles (SDV's) would operate initially in an 'expandable mode' with NTR lunar transfer vehicles (LTV's) delivering 80 percent more payload on piloted missions than their LOX/LH2 chemical propulsion counterparts. With the establishment of LUNOX production facilities on the lunar surface and 'fuel/oxidizer' depot in low lunar orbit (LLO), monopropellant NTR's would be outfitted with an oxygen propellant module, feed system, and afterburner nozzle for 'bipropellant' operation. The LANTR cislunar LTV now transitions to a reusable mode with smaller vehicle and payload doubling benefits on

  11. Propulsion

    ERIC Educational Resources Information Center

    Air and Space, 1978

    1978-01-01

    An introductory discussion of aircraft propulsion is included along with diagrams and pictures of piston, turbojet, turboprop, turbofan, and jet engines. Also, a table on chemical propulsion is included. (MDR)

  12. Propulsion

    ERIC Educational Resources Information Center

    Air and Space, 1978

    1978-01-01

    An introductory discussion of aircraft propulsion is included along with diagrams and pictures of piston, turbojet, turboprop, turbofan, and jet engines. Also, a table on chemical propulsion is included. (MDR)

  13. Evaluating User Experience of Augmented Reality Eyeglasses.

    PubMed

    Gamberini, Luciano; Orso, Valeria; Beretta, Andrea; Jacucci, Giulio; Spagnolli, Anna; Rimondi, Romina

    2015-01-01

    Augmented reality based applications have been experimented with in various contexts. Typically, the interaction is supported by handled devices, which, in specific scenarios, may hinder the interaction and spoil the experience of use, as the user is forced to hold the device and to keep her eyes on it at all times. The recent launch on the market of light-weight, unobtrusive head-mounted displays may change this circumstance. Nevertheless, investigations are needed to understand if such head-worn devices effectively outperform handheld devices in terms of comfort and pleasant experience of use. Here we present two experiments aimed at assessing the comfort of wearing a head-worn, see-through AR viewer in both a controlled and a natural setting. Besides the comfort of wearing the device, aspects related to the user experience were also investigated in the field evaluation. Our findings suggest that the head-mounted display examined is comfortable to wear regardless of the context of use. Interestingly in the field trails, participants did not express concern for the impression they would have made on other people and the experience of use was overall pleasant. Possible issues related to visual fatigue emerged.

  14. Human Exploration and Settlement of the Moon Using LUNOX-Augmented NTR Propulsion

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; Culver, Donald W.; Bulman, Melvin J.

    1995-01-01

    An innovative trimodal nuclear thermal rocket (NTR) concept is described which combines conventional liquid hydrogen (LH2)-cooled NTR, Brayton cycle power generation and supersonic combustion ramjet (scramjet) technologies. Known as the liquid oxygen (LOX) augmented NTR (LANTR), this concept utilizes the large divergent section of the NTR nozzle as an 'afterburner' into which LOX is injected and supersonically combusted with nuclear preheated hydrogen emerging from the LANTR's choked sonic throat--'scramjet propulsion in reverse.' By varying the oxygen-to-hydrogen mixture ratio (MR), the LANTR can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. As the MR varies from zero to seven, the thrust-to-weight ratio for a 15 thousand pound force (klbf) NTR increases by approximately 440%--from 3 to 13--while the Isp decreases by only approximately 45%--from 940 to 515 seconds. This thrust augmentation feature of the LANTR means that 'big engine' performance can be obtained using smaller more affordable, easier to test NTR engines. 'Reoxidizing' the bipropellant LANTR system in low lunar orbit (LLO) with high density 'lunar-derived' LOX (LUNOX) enables a reusable, reduced size and mass lunar transfer vehicle (LTV) which can be deployed and resupplied using two 66 t-class Shuttle-derived launch vehicles. The reusable LANTR can also transport 200 to 300% more payload on each piloted round trip mission than an expendable 'all LH2' NTR system. As initial outposts grow to eventual lunar settlements and LUNOX production capacity increases, the LANTR concept can also enable a rapid 'commuter' shuttle capable of 36 to 24 hour 'one way' trips to the Moon and back with reasonable size vehicles and initial mass in low Earth orbit (IMLEO) requirements.

  15. A Propellantless Propulsion Experiment Design and Testing Plan

    NASA Astrophysics Data System (ADS)

    Goodwin, David P.

    2004-02-01

    A propellantless propulsion experiment design and testing plan are described. The concept was initially presented during the Space Technology and Applications International Forum of 2001 and the experiment was initially presented during the Joint Propulsion Conference of 2001. New information is provided on how the experiment relates to the Human Exploration of Development of Space, the results of peer reviews, a cost estimate performed by a major U.S. aerospace company, and an alternative magnet design to reduce the cost of the experiment and potentially improve the reliability of the system. Recent improvements in high power solid state switches and superconducting magnets may have made propellantless propulsion possible. Propulsion may occur during the non-steady state ramp-up of a very rapidly pulsed, high power magnet. Propulsion would not occur after the first 100 nanoseconds of each pulse, since the magnetic field will have reached steady state. The United States Department of Energy Office of High Energy Physics provided some of the funding for the developed a no maintenance superconducting magnet that can carry 2,000 amperes per square millimeter and a switch which can provide 100 nanosecond ramp-ups at a rate of 0.4 megahertz, and at 9,000 volts and 30 amperes.

  16. A Propellantless Propulsion Experiment Design and Testing Plan

    SciTech Connect

    Goodwin, David P.

    2004-02-04

    A propellantless propulsion experiment design and testing plan are described. The concept was initially presented during the Space Technology and Applications International Forum of 2001 and the experiment was initially presented during the Joint Propulsion Conference of 2001. New information is provided on how the experiment relates to the Human Exploration of Development of Space, the results of peer reviews, a cost estimate performed by a major U.S. aerospace company, and an alternative magnet design to reduce the cost of the experiment and potentially improve the reliability of the system. Recent improvements in high power solid state switches and superconducting magnets may have made propellantless propulsion possible. Propulsion may occur during the non-steady state ramp-up of a very rapidly pulsed, high power magnet. Propulsion would not occur after the first 100 nanoseconds of each pulse, since the magnetic field will have reached steady state. The United States Department of Energy Office of High Energy Physics provided some of the funding for the developed a no maintenance superconducting magnet that can carry 2,000 amperes per square millimeter and a switch which can provide 100 nanosecond ramp-ups at a rate of 0.4 megahertz, and at 9,000 volts and 30 amperes.

  17. Electromagnetic emission experiences using electric propulsion systems: A survey

    NASA Technical Reports Server (NTRS)

    Sovey, James S.; Zana, Lynnette M.; Knowles, Steven C.

    1987-01-01

    As electric propulsion systems become ready to integrate with spacecraft systems, the impact of propulsion system radiated emissions are of significant interest. Radiated emissions from electromagnetic, electrostatic, and electrothermal systems have been characterized and results synopsized from the literature describing 21 space flight programs. Electromagnetic radiated emission results from ground tests and flight experiences are presented with particular attention paid to the performance of spacecraft subsystems and payloads during thruster operations. The impacts to transmission of radio frequency signals through plasma plumes are also reviewed.

  18. Electromagnetic emission experiences using electric propulsion systems - A survey

    NASA Technical Reports Server (NTRS)

    Sovey, James S.; Zana, Lynnette M.; Knowles, Steven C.

    1987-01-01

    As electric propulsion systems become ready to integrate with spacecraft systems, the impact of propulsion system radiated emissions are of significant interest. Radiated emissions from electromagnetic, electrostatic, and electrothermal systems have been characterized and results synopsized from the literature describing 21 space flight programs. Electromagnetic radiated emission results from ground tests and flight experiences are presented with particular attention paid to the performance of spacecraft subsystems and payloads during thruster operations. The impacts to transmission of radio frequency signals through plasma plumes are also reviewed.

  19. Transient Region Coverage in the Propulsion IVHM Technology Experiment

    NASA Technical Reports Server (NTRS)

    Balaban, Edward; Sweet, Adam; Bajwa, Anupa; Maul, William; Fulton, Chris; Chicatelli, amy

    2004-01-01

    Over the last several years researchers at NASA Glenn and Ames Research Centers have developed a real-time fault detection and isolation system for propulsion subsystems of future space vehicles. The Propulsion IVHM Technology Experiment (PITEX), as it is called follows the model-based diagnostic methodology and employs Livingstone, developed at NASA Ames, as its reasoning engine. The system has been tested on,flight-like hardware through a series of nominal and fault scenarios. These scenarios have been developed using a highly detailed simulation of the X-34 flight demonstrator main propulsion system and include realistic failures involving valves, regulators, microswitches, and sensors. This paper focuses on one of the recent research and development efforts under PITEX - to provide more complete transient region coverage. It describes the development of the transient monitors, the corresponding modeling methodology, and the interface software responsible for coordinating the flow of information between the quantitative monitors and the qualitative, discrete representation Livingstone.

  20. Solar System Exploration Augmented by In-Situ Resource Utilization: Mercury and Saturn Propulsion Investigations

    NASA Technical Reports Server (NTRS)

    Palaszewski, Bryan

    2016-01-01

    Human and robotic missions to Mercury and Saturn are presented and analyzed with a range of propulsion options. Historical studies of space exploration, in-situ resource utilization (ISRU), and industrialization all point to the vastness of natural resources in the solar system. Advanced propulsion benefitted from these resources in many ways. While advanced propulsion systems were proposed in these historical studies, further investigation of nuclear options using high power nuclear thermal and nuclear pulse propulsion as well as advanced chemical propulsion can significantly enhance these scenarios. Updated analyses based on these historical visions will be presented. Nuclear thermal propulsion and ISRU enhanced chemical propulsion landers are assessed for Mercury missions. At Saturn, nuclear pulse propulsion with alternate propellant feed systems and Titan exploration with chemical propulsion options are discussed. In-situ resource utilization was found to be critical in making Mercury missions more amenable for human visits. At Saturn, refueling using local atmospheric mining was found to be difficult to impractical, while refueling the Saturn missions from Uranus was more practical and less complex.

  1. Flowing DPF Design for Propulsion Experiments

    DTIC Science & Technology

    1993-08-01

    operation has been performed before in experiments on coaxial 24 plasma guns operating in the deflagration mode.1111 However, these experiments provided...measurements made on coaxial plasma guns in the deflagration mode show a particle velocity of 106 m/s.1 131 Operating the DPF in the gas-injected mode...measurement techniques have been studied for other thrusters (ion, plasma , etc.)[18l[191[20 ], however only some of these methods are suitable for the low

  2. Solar array flight experiment/dynamic augmentation experiment

    NASA Technical Reports Server (NTRS)

    Young, Leighton E.; Pack, Homer C., Jr.

    1987-01-01

    This report presents the objectives, design, testing, and data analyses of the Solar Array Flight Experiment/Dynamic Augmentation Experiment (SAFE/DAE) that was tested aboard Shuttle in September 1984. The SAFE was a lightweight, flat-fold array that employed a thin polyimide film (Kapton) as a substrate for the solar cells. Extension/retraction, dynamics, electrical and thermal tests, were performed. Of particular interest is the dynamic behavior of such a large lightweight structure in space. Three techniques for measuring and analyzing this behavior were employed. The methodology for performing these tests, gathering data, and data analyses are presented. The report shows that the SAFE solar array technology is ready for application and that new methods are available to assess the dynamics of large structures in space.

  3. Experiments on Cruise Propulsion with a Hydrogen Scramjet

    NASA Technical Reports Server (NTRS)

    Stalker, R. J.; Paull, A.

    1998-01-01

    Measurement of drag have been made in a shock tunnel on a simple integrated vehicle engine combination for hypersonic cruise with hydrogen scramjet propulsion. The test flow Mach number was 6.4, and the velocity was 2.45 kms(exp -1). Zero Drag, which is the necessary condition for cruise, was achieved as the equivalence ratio approached one. It was found that an analysis using established aerodynamic concept was adequate for predicting drag in the case of no combustion. When combustion occurred results of direct connect experiments provided was qualitative guide to the measured levels of drag, and indicated that thrust nozzle combustion was taking place. An heuristic analysis is used to point to the important effect this may have on propulsive lift.

  4. Gravel Augmentation Below Dams: California Experiences

    NASA Astrophysics Data System (ADS)

    Kondolf, G. M.; Minear, J. T.

    2004-12-01

    Most dams block all coarse sediment traveling downstream, such that reaches downstream are commonly typically depleted of gravel, causing a variety of effects such as incision, bank erosion, coarsening of the bed material, and reduction of salmonid spawning habitiat. To compensate for this reduction in coarse sediment supply, gravel has been artificially added below dams, using techniques such as high flow stock piling, high flow direct injection, artificial riffle construction, riffle supplementation, and construction of side channel or artificial spawning channels. In the Trinity and Sacramento-San Joaquin River systems of northern California, loss of suitable salmonid spawning gravels below dams has motivated augmentation of over 320,000 m3 of gravel in 73 separate projects on 19 rivers since 1978, mostly since 1990. Of the 67 projects for which adequate data were available, 48 involved adding less than 7,500 m3 each. Costs reported for 57 of the projects totaled nearly $8,753,000, but these figures generally did not include the cost of staff time involved in planning, design, and oversight. Despite the magnitude of this experimental intervention, fewer than half of the projects were monitored, and of those few had monitored sufficient parameters pre- and post- project to evaluate project performance. Performance of these projects to date has been mixed: in many cases the imported gravels have promptly washed out, some channel forms created have been unnatural and not heavily used by salmon. In all cases, the volumes of gravel artificially added have been only a small percentage of the annual coarse sediment deficit.

  5. Augmented Becoming: Personal Reflections on Collaborative Experience

    ERIC Educational Resources Information Center

    Barak, Judith

    2015-01-01

    This self-study is an exploratory, autoethnographic journey, aiming towards understanding my becomings through the 14 years of my collaborative experience. It provides a reflective look at the effects of this unique experience on my personal-professional self, questioning my understandings and trying to identify my becomings along these years.…

  6. Propulsion Integrated Vehicle Health Management Technology Experiment (PITEX) Conducted

    NASA Technical Reports Server (NTRS)

    Maul, William A.; Chicatelli, Amy K.; Fulton, Christopher E.

    2004-01-01

    The Propulsion Integrated Vehicle Health Management (IVHM) Technology Experiment (PITEX) is a continuing NASA effort being conducted cooperatively by the NASA Glenn Research Center, the NASA Ames Research Center, and the NASA Kennedy Space Center. It was a key element of a Space Launch Initiative risk-reduction task performed by the Northrop Grumman Corporation in El Segundo, California. PITEX's main objectives are the continued maturation of diagnostic technologies that are relevant to second generation reusable launch vehicle (RLV) subsystems and the assessment of the real-time performance of the PITEX diagnostic solution. The PITEX effort has considerable legacy in the NASA IVHM Technology Experiment for X-vehicles (NITEX) that was selected to fly on the X-34 subscale RLV that was being developed by Orbital Sciences Corporation. NITEX, funded through the Future-X Program Office, was to advance the technology-readiness level of selected IVHM technologies within a flight environment and to begin the transition of these technologies from experimental status into RLV baseline designs. The experiment was to perform realtime fault detection and isolation and suggest potential recovery actions for the X-34 main propulsion system (MPS) during all mission phases by using a combination of system-level analysis and detailed diagnostic algorithms.

  7. Propulsion Integrated Vehicle Health Management Technology Experiment (PITEX) Conducted

    NASA Technical Reports Server (NTRS)

    Maul, William A.; Chicatelli, Amy K.; Fulton, Christopher E.

    2004-01-01

    The Propulsion Integrated Vehicle Health Management (IVHM) Technology Experiment (PITEX) is a continuing NASA effort being conducted cooperatively by the NASA Glenn Research Center, the NASA Ames Research Center, and the NASA Kennedy Space Center. It was a key element of a Space Launch Initiative risk-reduction task performed by the Northrop Grumman Corporation in El Segundo, California. PITEX's main objectives are the continued maturation of diagnostic technologies that are relevant to second generation reusable launch vehicle (RLV) subsystems and the assessment of the real-time performance of the PITEX diagnostic solution. The PITEX effort has considerable legacy in the NASA IVHM Technology Experiment for X-vehicles (NITEX) that was selected to fly on the X-34 subscale RLV that was being developed by Orbital Sciences Corporation. NITEX, funded through the Future-X Program Office, was to advance the technology-readiness level of selected IVHM technologies within a flight environment and to begin the transition of these technologies from experimental status into RLV baseline designs. The experiment was to perform realtime fault detection and isolation and suggest potential recovery actions for the X-34 main propulsion system (MPS) during all mission phases by using a combination of system-level analysis and detailed diagnostic algorithms.

  8. High temperature latent heat thermal energy storage to augment solar thermal propulsion for microsatellites

    NASA Astrophysics Data System (ADS)

    Gilpin, Matthew R.

    Solar thermal propulsion (STP) offers an unique combination of thrust and efficiency, providing greater total DeltaV capability than chemical propulsion systems without the order of magnitude increase in total mission duration associated with electric propulsion. Despite an over 50 year development history, no STP spacecraft has flown to-date as both perceived and actual complexity have overshadowed the potential performance benefit in relation to conventional technologies. The trend in solar thermal research over the past two decades has been towards simplification and miniaturization to overcome this complexity barrier in an effort finally mount an in-flight test. A review of micro-propulsion technologies recently conducted by the Air Force Research Laboratory (AFRL) has identified solar thermal propulsion as a promising configuration for microsatellite missions requiring a substantial Delta V and recommended further study. A STP system provides performance which cannot be matched by conventional propulsion technologies in the context of the proposed microsatellite ''inspector" requiring rapid delivery of greater than 1500 m/s DeltaV. With this mission profile as the target, the development of an effective STP architecture goes beyond incremental improvements and enables a new class of microsatellite missions. Here, it is proposed that a bi-modal solar thermal propulsion system on a microsatellite platform can provide a greater than 50% increase in Delta V vs. chemical systems while maintaining delivery times measured in days. The realization of a microsatellite scale bi-modal STP system requires the integration of multiple new technologies, and with the exception of high performance thermal energy storage, the long history of STP development has provided "ready" solutions. For the target bi-modal STP microsatellite, sensible heat thermal energy storage is insufficient and the development of high temperature latent heat thermal energy storage is an enabling

  9. Current Status of the Gasdynamic Mirror Fusion Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.

    2002-01-01

    Nuclear fusion appears to be the most promising concept for producing extremely high specific impulse rocket engines. One particular fusion concept which seems to be particularly well suited for fusion propulsion applications is the gasdynamic mirror (GDM). An experimental GDM device has been constructed at the NASA Marshall Space Flight Center to provide an initial assessment of the feasibility of this type of propulsion system. An initial shakedown of the device is currently underway with initial experiments slated to occur in late 2001. This device would operate at much higher plasma densities and with much larger L/D ratios than previous mirror machines. The high L/D ratio minimizes to a large extent certain magnetic curvature effects which lead to plasma instabilities causing a loss of plasma confinement. The high plasma density results in the plasma behaving much more like a conventional fluid with a mean free path shorter than the length of the device. This characteristic helps reduce problems associated with 'loss cone' microinstabilities. The device has been constructed to allow a considerable degree of flexibility in its configuration thus permitting the experiment to grow over time without necessitating a great deal of additional fabrication.

  10. Local Flow Conditions for Propulsion Experiments on the NASA F-15B Propulsion Flight Test Fixture

    NASA Technical Reports Server (NTRS)

    Vachon, Michael J.; Moes, Timothy R.; Corda, Stephen

    2005-01-01

    Local flow conditions were measured underneath the National Aeronautics and Space Administration F-15B airplane to support development of future experiments on the Propulsion Flight Test Fixture (PFTF). The local Mach number and flow angles were measured using a conventional air data boom on a cone-cylinder mounted under the PFTF and compared with the airplane air data nose boom measurements. At subsonic flight speeds, the airplane and PFTF Mach numbers were approximately equal. Transonic Mach number values were up to 0.1 greater at the PFTF than the airplane, which is a counterintuitive result. The PFTF local supersonic Mach numbers were as much as 0.46 less than the airplane values. The maximum local Mach number at the PFTF was approximately 1.6 at an airplane Mach number near 2.0. The PFTF local angle of attack was negative at all Mach numbers, ranging from -3 to -8 degrees. When the airplane angle of sideslip was zero, the PFTF local value was zero between Mach 0.8 and Mach 1.1, -2 degrees between Mach 1.1 and Mach 1.5, and increased from zero to 1 degree from Mach 1.5 to Mach 2.0. Airplane inlet shock waves crossed the aerodynamic interface plane between Mach 1.85 and Mach 1.90.

  11. Thrust Measurements in Ballistic Pendulum Ablative Laser Propulsion Experiments

    SciTech Connect

    Brazolin, H.; Rodrigues, N. A. S.; Minucci, M. A. S.

    2008-04-28

    This paper describes a setup for thrust measurement in ablative laser propulsion experiments, based on a simple ballistic pendulum associated to an imaging system, which is being assembled at IEAv. A light aluminium pendulum holding samples is placed inside a 100 liters vacuum chamber with two optical windows: the first (in ZnSe) for the laser beam and the second (in fused quartz) for the pendulum visualization. A TEA-CO{sub 2} laser beam is focused to the samples providing ablation and transferring linear moment to the pendulum as a whole. A CCD video camera captures the oscillatory movement of the pendulum and the its trajectory is obtained by image processing. By fitting the trajectory of the pendulum to a dumped sinusoidal curve is possible to obtain the amplitude of the movement which is directly related to the momentum transfered to the sample.

  12. Joint Langley Research Center/Jet Propulsion Laboratory CSI experiment

    NASA Technical Reports Server (NTRS)

    Neat, Gregory W.; O'Brien, John F.; Lurie, Boris J.; Garnica, Angel; Belvin, W. K.; Sulla, Jeff; Won, John

    1992-01-01

    This paper describes a joint Control Structure Interaction (CSI) experiment in which Jet Propulsion Laboratory (JPL) damping devices were incorporated into the Langley Research Center (LaRC) Phase 0 Testbed. The goals of the effort were twofold: (1) test the effectiveness of the JPL structural damping methods in a new structure and (2) assess the feasibility of combining JPL local control methods with the LaRC multiple input multiple output global control methods. Six dampers (2 piezoelectric active members, 4 viscous dampers), placed in three different regions of the structure, produced up to 26 dB attenuation in target modes. The combined control strategy in which the JPL damping methods contributed local control action and the LaRC control scheme provided global control action, produced and overall control scheme with increased stability margins and improved performance. This paper presents an overview of the technologies contributed from the two centers, the strategies used to combine them, and results demonstrating the success of the damping and cooperative control efforts.

  13. First Results of the Gasdynamic Mirror Fusion Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.

    2002-01-01

    An experimental Gasdynamic Mirror or GDM device has been constructed at the NASA Marshall Space Flight Center to provide an initial assessment of the applicability of this technology for propulsion systems. This paper presents the first experimental results obtained from the machine and an analysis of the types of plasma instabilities likely to be encountered. It is intended that this device operate at higher plasma densities and with much larger L/D ratios than previous mirror machines. The high L/D ratio minimizes to a large extent certain magnetic curvature effects which lead to plasma instabilities causing a loss of plasma confinement. The high plasma density results in the plasma behaving much more like a conventional fluid with a mean free path shorter than the length of the device. This characteristic helps reduce problems associated with "loss cone" microinstabilities. The device has been constructed to allow a considerable degree of flexibility in its configuration thus permitting the experiment to grow over time without necessitating a great deal of additional fabrication.

  14. Supersonic combustion ramjet propulsion experiments in a shock tunnel

    NASA Technical Reports Server (NTRS)

    Paull, A.; Stalker, R. J.; Mee, D. J.

    1995-01-01

    Measurements have been made of the propulsive effect of supersonic combustion ramjets incorporated into a simple axisymmetric model in a free piston shock tunnel. The nominal Mach number was 6, and the stagnation enthalpy varied from 2.8 MJ kg(exp -1) to 8.5 MJ kg(exp -1). A mixture of 13 percent silane and 87 percent hydrogen was used as fuel, and experiments were conducted at equivalence ratios up to approximately 0.8. The measurements involved the axial force on the model, and were made using a stress wave force balance, which is a recently developed technique for measuring forces in shock tunnels. A net thrust was experienced up to a stagnation enthalpy of 3.7 MJ kg(exp -1), but as the stagnation enthalpy increased, an increasing net drag was recorded. pitot and static pressure measurements showed that the combustion was supersonic. The results were found to compare satisfactorily with predictions based on established theoretical models, used with some simplifying approximations. The rapid reduction of net thrust with increasing stagnation enthalpy was seen to arise from increasing precombustion temperature, showing the need to control this variable if thrust performance was to be maintained over a range of stagnation enthalpies. Both the inviscid and viscous drag were seen to be relatively insensitive to stagnation enthalpy, with the combustion chambers making a particularly significant contribution to drag. The maximum fuel specific impulse achieved in the experiments was only 175 sec., but the theory indicates that there is considerable scope for improvement on this through aerodynamic design.

  15. Explosive propulsion applications. [to future unmanned missions

    NASA Technical Reports Server (NTRS)

    Nakamura, Y.; Varsi, G.; Back, L. H.

    1974-01-01

    The feasibility and application of an explosive propulsion concept capable of supporting future unmanned missions in the post-1980 era were examined and recommendations made for advanced technology development tasks. The Venus large lander mission was selected as the first in which the explosive propulsion concept can find application. A conceptual design was generated and its performance, weight, costs, and interaction effects determined. Comparisons were made with conventional propulsion alternatives. The feasibility of the explosive propulsion system was verified for planetology experiments within the dense atmosphere of Venus as well as the outer planets. Additionally, it was determined that the Venus large lander mission could be augmented ballistically with a significant delivery margin.

  16. Results from a large-scale MHD propulsion experiment

    NASA Astrophysics Data System (ADS)

    Petrick, M.; Libera, J.; Bouillard, J. X.; Pierson, E. S.; Hill, D.

    Magnetohydrodynamic (MHD) thrusters have long been recognized as potentially attractive candidates for ship propulsion because such systems eliminate the conventional rotating drive components. The MHD thruster is essentially an electromagnetic (EM) pump operating in seawater. An electrical current is passed directly through the seawater and interacts with an applied magnetic field; the interaction of the magnetic field and the electrode current in the seawater results in a Lorentz force acting on the water, and the reaction to this force propels the vessel forward. The concept of EM propulsion has been examined periodically during the past 35 years as an alternative method of propulsion for surface ships and submersibles. The conclusions reached in early studies were that MHD thrusters restricted to fields of 2 T (the state-of-the-art at that time) were impractical and very inefficient. With the evolution of superconducting magnet technology, later studies investigated the performance of MHD thrusters with much higher magnetic field strengths and concluded that at higher fields (greater than 6-T) practical MHD propulsion systems appear possible. The feasibility of attaining the requisite higher magnetic fields has increased markedly because of rapid advances in building high-field superconducting magnets and the recent evolution of high-temperature superconductors.

  17. Experiments on hypersonic ramjet propulsion cycles using a ram accelerator

    NASA Technical Reports Server (NTRS)

    Chew, G.; Knowlen, C.; Burnham, E. A.; Hertzberg, A.; Bruckner, A. P.

    1991-01-01

    Work on hypersonic propulsion research using a ram accelerator is presented. Several different ram accelerator propulsive cycles have been experimentally demonstrated over the Mach number range of 3 to 8.5. The subsonic, thermally choked combustion mode has accelerated projectiles to near the Chapman-Jouguet (C-J) detonation velocity within many different propellant mixtures. In the transdetonative velocity regime (85 to 115 percent of C-J speed), projectiles have established a propulsive cycle which allows them to transition smoothly from subdetonative to superdetonative velocities. Luminosity data indicate that the combustion process moves forward onto the projectile body as it approaches the C-J speed. In the superdetonative velocity range, the projectiles accelerate while always traveling faster than the C-J velocity. Ram accelerator projectiles operating continuously through these velocity regimes generate distinctive hypersonic phenomena which can be studied very effectively in the laboratory. These results would be very useful for validating sophisticated CFD computer codes and in collecting engineering data for potential airbreathing hypersonic propulsive systems.

  18. archAR: an archaeological augmented reality experience

    NASA Astrophysics Data System (ADS)

    Wiley, Bridgette; Schulze, Jürgen P.

    2015-03-01

    We present an application for Android phones or tablets called "archAR" that uses augmented reality as an alternative, portable way of viewing archaeological information from UCSD's Levantine Archaeology Laboratory. archAR provides a unique experience of flying through an archaeological dig site in the Levantine area and exploring the artifacts uncovered there. Using a Google Nexus tablet and Qualcomm's Vuforia API, we use an image target as a map and overlay a three-dimensional model of the dig site onto it, augmenting reality such that we are able to interact with the plotted artifacts. The user can physically move the Android device around the image target and see the dig site model from any perspective. The user can also move the device closer to the model in order to "zoom" into the view of a particular section of the model and its associated artifacts. This is especially useful, as the dig site model and the collection of artifacts are very detailed. The artifacts are plotted as points, colored by type. The user can touch the virtual points to trigger a popup information window that contains details of the artifact, such as photographs, material descriptions, and more.

  19. ARTEMIS orbit raising inflight experience with ion propulsion

    NASA Astrophysics Data System (ADS)

    Killinger, Rainer; Kukies, Ralf; Surauer, Michael; Tomasetto, Angeo; van Holtz, Leo

    2003-08-01

    To demonstrate and promote North/South station keeping (inclination control) using ion propulsion, ESA on July 12, 2001 onboard Ariane 510 launched its most advanced telecommunication satellite: ARTEMIS. Due to a launcher failure the satellite was injected into a useless too low elliptic orbit. The ARTEMIS mission was salvaged by an Alenia Spazio / Astrium / ESA team at Telespazio (Fucino) using in novel modes to operate the on-board chemical and ion propulsion systems provided by Astrium. Using the chemical propulsion_ system provided by Astrium GmbH - Lampoldshausen - the inital orbit, having an apogee of half the targeted altitude. was quickly upgraded to a safe circular parking orbit at 31000 km altitude. The Liquid Apogee Engine was fired in total 8 times to achieve apogee as well as perigee raising. The final orbit raising to geostationary altitude is being performed by means of the ion propulsion system (IPP) applied in a newly designed spacecraft attitude control mode. Alenia Spazio and Astrium, in close cooperation, quickly redesigned all control and data handling software modules affected since the original spacecraft configuration was designed for inclination control only and not to generate thrust with the ion engines in a direction tangential to the orbit. The flexibility of the IPP system consisting of 4 thruster assemblies, provided in its totality by Astrium including the 2 alignment mechanisms for precision thrust direction control, had proven invaluable. To demonstrate the technologies available in Europe and to enhanced reliability, Astrium implemented two different technologies: a Kaufmann type system (EITA) provided by Astrium Ltd. - Portsmouth; and a Radiofrequency Ion Thruster Assembly (RITA) provided by Astrium GmbH - Ottobrunn. Two ion engines of different technology were mounted side by side on one ITAM (Ion Thruster Alignment Mechanism) provided by Austrian Aerospace. Artemis, after EURECA launched on 31 July 1992 and retrieved on 1 July

  20. ARTEMIS Orbit Raising Inflight Experience with Ion Propulsion

    NASA Astrophysics Data System (ADS)

    Killinger, Rainer

    2002-01-01

    To demonstrate and promote North/South station keeping (inclination control) using ion propulsion, ESA on July 12, 2001 onboard Ariane 510 launched its most advanced telecommunication satellite: ARTEMIS. Due to a launcher failure the satellite was injected into a useless too low elliptic orbit. The ARTEMIS mission was salvaged by the ALTEL/Astrium/ESA team at Telespazio (Fucino) using in novel modes of operation the on-board chemical and ion propulsion systems provided by Astrium. Using the chemical propulsion system provided by Astrium GmbH - Lampoldshausen - the inital orbit, having an apogee of half the targeted altitude. was quickly upgraded to a safe circular parking orbit at 31000 km altitude. The Liquid Apogee Engine was fired in total 8 times to achieve perigee as well as apogee raising. The final orbit raising to geostationary altitude is being performed by means of the ion propulsion system (IPP) applied in a newly designed spacecraft attitude control mode. Alenia Spazio and Astrium, in close cooperation, quickly redesigned all control and data handling software modules affected since the original spacecraft configuration was designed for inclination control only and not to generate thrust with the ion engines in a direction tangential to the orbit. The flexibility of the IPP system consisting of 4 thruster assemblies, provided in its totality by Astrium including the 2 alignment mechanisms for precision thrust direction control, had proven invaluable. To demonstrate the technologies available in Europe and to enhanced reliability, Astrium implemented two different technologies: a Kaufmann type system (EITA) provided by Astrium Ltd. - Portsmouth, and a Radiofrequency Ion Thruster Assembly (RITA) provided by Astrium GmbH - Ottobrunn. Two ion engines of different technology were mounted side by side on one ITAM (Ion Thruster Alignment Mechanism) provided by Austrian Aerospace. This paper, after a brief description of the ion propulsion system, will

  1. Experiments in augmented teleoperation for mobile robots: I

    NASA Astrophysics Data System (ADS)

    Witus, Gary; Hunt, Shawn; Ellis, R. Darrin

    2007-04-01

    Teleoperated mobile robots are beginning to be used for a variety of tasks that require movement in close quarters in the vicinity of moving and parked vehicles, buildings and other man-made structures, and the target object for inspection or manipulation. The robots must be close enough to deploy short-range sensors and manipulators, and must be able to maneuver without potentially damaging collisions. Teleoperation is fatiguing and stressful even without the requirement for close positioning. In cooperation with the TARDEC Robotic Mobility Laboratory (TRML), we are investigating approaches to reduce workload and improve performance through augmented teleoperation. Human-robot interfaces for teleoperation commonly provide two degrees-of-freedom (DoF) motion control with visual feedback from an on-board egocentric camera and no supplemental distance or orientation cueing. This paper reports on the results of preliminary experiments to assess the effects on man-machine task performance of several options for augmented teleoperation: (a) 3 DoF motion control (rotation and omni-directional translation) versus 2 DoF control (rotation and forward/reverse motion), (b) on-board egocentric camera versus fixed-position overwatch camera versus dual egocentric-and-overwatch cameras, and (c) presence or absence of distance and orientation visual cueing. We examined three dimensions of performance: completion time, spatial accuracy, and workspace area. We investigated effects on the expected completion time and on the variance in completion time. Spatial accuracy had three components: orientation, aimpoint, and distance. We collected performance under different task conditions: (a) three position-and-orientation tolerance or accuracy objectives, and (b) four travel distances between successive inspection points. We collected data from three subjects. We analyzed the main effects and conditional interaction effects among the teleoperation options and task conditions. We were

  2. Feasibility of a responsive, hybrid propulsion augmented, Vertical-Takeoff-and-Landing, Single-Stage-to-Orbit launch system

    NASA Astrophysics Data System (ADS)

    Pelaccio, Dennis G.

    1996-03-01

    A novel, reusable, Vertical-Takeoff-and-Landing, Single-Stage-to-Orbit (VTOL/SSTO) launch system concept, named HYP-SSTO, is presented in this paper. This launch vehicle system concept uses a highly coupled, main high performance liquid oxygen/liquid hydrogen (LOX/LH2) propulsion system, that is used only for launch, with a hybrid auxiliary propulsion system which is used during final orbit insertion, major orbit maneuvering, and landing propulsive burn phases of flight. By using a hybrid propulsion system for major orbit maneuver burns and landing, this launch system concept has many advantages over conventional VTOL/SSTO concepts that use LOX/LH2 propulsion system(s) burns for all phases of flight. Because hybrid propulsion systems are relatively simple and inert by their nature, this concept has the potential to support short turnaround times between launches, be economical to develop, and be competitive in terms of overall system life-cycle cost. This paper provides a technical description of the novel, reusable HYP-SSTO launch system concept. Launch capability performance, as well as major design and operational system attributes, are identified and discussed.

  3. Exhaust System Experiments at NASA's AeroAcoustic Propulsion Lab

    NASA Technical Reports Server (NTRS)

    Bridges, James

    2011-01-01

    This presentation gives an overview of the planned testing in the AeroAcoustic Propulsion Lab (AAPL) in the coming 15 months. It was stressed in the presentation that these are plans that are subject to change due to changes in funding and/or programmatic direction. The first chart shows a simplified schedule of test entries with funding sponsor and dates for each. In subsequent charts are pages devoted to the Objectives and Issues with each test entry, along with a graphic intended to represent the test activity. The chart for each test entry also indicates sponsorship of the activity, and a contact person.!

  4. The meaning of communication: experiences with augmentative communication devices.

    PubMed

    Dickerson, Suzanne Steffan; Stone, Vathsala I; Panchura, Carly; Usiak, Douglas J

    2002-01-01

    This study is a secondary analysis of data collected from end-users of Augmentative and Alternative Communication (AAC) devices as part of a project of the Rehabilitation Engineering Research Center on Technology Transfer (T2RERC). The original data, obtained from a Web-based focus group, were used to identify unmet consumer needs in existing AAC devices. The purpose of the secondary analysis was to give context to the original study through phenomenological interpretation of the narratives, thereby gaining an understanding of the common meanings and shared experiences and practices of people who use AAC technology. Underlying this study is the interpretive approach of Heideggerian hermeneutics; through reflective thinking, understanding of the human situation of AAC users in everyday life is uncovered or extended. Six themes and one constitutive pattern emerged to explain the participants' experiences with AAC devices: (a) maintaining effective communication, (b) interacting in various situations, (c) AAC device-imposing limitations, (d) wading through prepackaged technology, (e) AAC device giving more than a voice, (f) accepting the AAC device. The constitutive pattern was communication technology enables humanness. This information will make rehabilitation nurses aware of the value of the AAC device for the users and the limitations that the technology may impose on the users, as well as the need for others to accept the device. Nurses gaining this understanding may facilitate integration of AAC systems and the development of patient/nurse communication partnerships.

  5. Thermal Design and Flight Experience of the Mars Exploration Rover Spacecraft Computer-Controlled, Propulsion Line Heaters

    NASA Technical Reports Server (NTRS)

    Novak, Keith; Kinsella, Gary; Krylo, Robert; Sunada, Eric

    2004-01-01

    The viewgraph presentation examines propulsion line heater design and problems in the Mars Rover. Topics include a Mars Exploration Rover (MER) project description and MER spacecraft configuration, mission overview, MER cruise stage hardware, thermal design drivers in the propulsion lines, propulsion line control set points prior to launch, MER A and B flight trajectories, MER A early and mid cruise flight experience, MER A and B mid cruise flight experience, MER B late cruise flight experience, and lessons learned

  6. Thermal Design and Flight Experience of the Mars Exploration Rover Spacecraft Computer-Controlled, Propulsion Line Heaters

    NASA Technical Reports Server (NTRS)

    Novak, Keith; Kinsella, Gary; Krylo, Robert; Sunada, Eric

    2004-01-01

    The viewgraph presentation examines propulsion line heater design and problems in the Mars Rover. Topics include a Mars Exploration Rover (MER) project description and MER spacecraft configuration, mission overview, MER cruise stage hardware, thermal design drivers in the propulsion lines, propulsion line control set points prior to launch, MER A and B flight trajectories, MER A early and mid cruise flight experience, MER A and B mid cruise flight experience, MER B late cruise flight experience, and lessons learned

  7. Electrodynamic Propulsion System Tether Experiment (T-REX)

    NASA Technical Reports Server (NTRS)

    Johnson, L.; Fujii, H. A.; Sanmartin, J. R.

    2010-01-01

    A Japanese-led international team is developing a suborbital test of orbital-motion-limited (OML) bare wire anode current collection for application to electrodynamic tether (EDT) propulsion. The tether is a tape with a width of 25 mm, thickness of 0.05 mm, and is 300 m in length. This will be the first space test of OML theory. The mission will launch in the summer of 2010 using an S520 Sounding Rocket. During ascent, and above approximately 100 km in attitude, the tape tether will be deployed at a rate of approximately8 m/s. Once deployed, the tape tether will serve as an anode, collecting ionospheric electrons. The electrons will be expelled into space by a hollow cathode device, thereby completing the circuit and allowing current to flow. The total amount of current collected will be used to assess the validity of OML theory. This paper will describe the objectives of the proposed mission, the technologies to be employed, and the application of the results to future space missions using EDTs for propulsion or power generation

  8. Propulsive Small Expendable Deployer System (ProSEDS) Experiment

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Estes, Robert; Lorenzini, Enrico; Gilchrist, Brian

    1999-01-01

    ProSEDS is a secondary (i.e. piggyback) payload on a Delta-11 GPS 8 mission scheduled for launch in August 2000. It will test the feasibility of generating generate electrodynamic thrust without propellant using a 5 kilometer conducting wire (tether). The ProSEDS obtains thrust as the tether cuts across the magnetic field, a voltage is induced across the wire. Electrons are attracted to the positively based far end of the wire. Electrons flow downward through the conductive tether. Earth's magnetic field exerts a drag force on the current in the tether segments, that is mechanically transferred via the wire to the stage. The primary objective for the ProSEDs mission is to demonstrate that a significant, measurable electrodynamic thrust through a tether in space. The primary mission will last one day, as the primary battery assures at least three orbits of data will be collected, the remaining power will be provided by the secondary battery, which uses tether generated power to recharge. The extended mission begins using the power provided through the tether, and wil terminate when a system ceases to function; (i.e., either degradation of the tether,through Atomic Oxygen contact, a micrometeoroid or other debris impact, or another malfunction.) The technology has many potential applications. Amongst the applications, which are reviewed in detail, are: (1) satellite deorbit, (2) reboost of the International Space Station, (3) propellantless reusable Orbit Transfer Vehicles, (4) Propulsion and power generation for future Jovian missions.

  9. Technically Speaking: On the Structure and Experience of Interaction Involving Augmentative Alternative Communications

    ERIC Educational Resources Information Center

    Engelke, Christopher Robert

    2013-01-01

    Technically Speaking: On the Structure and Experience of Interaction Involving Augmentative Alternative Communications examines the ways that communication is structured and experienced by looking at interactions involving augmented communicators--people with severe speech disabilities who use forms of assistive technology in order to communicate…

  10. Technically Speaking: On the Structure and Experience of Interaction Involving Augmentative Alternative Communications

    ERIC Educational Resources Information Center

    Engelke, Christopher Robert

    2013-01-01

    Technically Speaking: On the Structure and Experience of Interaction Involving Augmentative Alternative Communications examines the ways that communication is structured and experienced by looking at interactions involving augmented communicators--people with severe speech disabilities who use forms of assistive technology in order to communicate…

  11. Addressing the Real-World Challenges in the Development of Propulsion IVHM Technology Experiment (PITEX)

    NASA Technical Reports Server (NTRS)

    Maul, William A.; Chicatelli, Amy; Fulton, Christopher E.; Balaban, Edward; Sweet, Adam; Hayden, Sandra Claire; Bajwa, Anupa

    2005-01-01

    The Propulsion IVHM Technology Experiment (PITEX) has been an on-going research effort conducted over several years. PITEX has developed and applied a model-based diagnostic system for the main propulsion system of the X-34 reusable launch vehicle, a space-launch technology demonstrator. The application was simulation-based using detailed models of the propulsion subsystem to generate nominal and failure scenarios during captive carry, which is the most safety-critical portion of the X-34 flight. Since no system-level testing of the X-34 Main Propulsion System (MPS) was performed, these simulated data were used to verify and validate the software system. Advanced diagnostic and signal processing algorithms were developed and tested in real-time on flight-like hardware. In an attempt to expose potential performance problems, these PITEX algorithms were subject to numerous real-world effects in the simulated data including noise, sensor resolution, command/valve talkback information, and nominal build variations. The current research has demonstrated the potential benefits of model-based diagnostics, defined the performance metrics required to evaluate the diagnostic system, and studied the impact of real-world challenges encountered when monitoring propulsion subsystems.

  12. Operational experiments and thruster performance plan for the Nuclear Electric Propulsion Space Test Program (NEPSTP)

    NASA Astrophysics Data System (ADS)

    Bythrow, P. F.; Mauk, B. H.; Gatsonis, N. A.; Bokulic, R. S.

    1993-06-01

    The Nuclear Electric Propulsion Space Test Program (NEPSTP) is designed as a technology testbed for Nuclear Electric Propulsion (NEP). A Topaz II nuclear reactor will provide the required power and an array of Ion and Hall engines will be used for propulsion. NEPSTP will evaluate on orbit, and under the same set of environmental parameters, the performance and operational characteristics of competitive electric propulsion technologies each using Xenon gas as a propellant. NEPSTP, will be operating in the so called induced environment which is the result of interactions between the ambient and the contaminant environment and the spacecraft itself. The interactions of a conventional solar/chemical spacecraft with the induced environment have been studied extensively and certain aspects are now well understood. Other aspects specific to electric propulsion such as spacecraft interactions with the plasma environment, charging, or the motion of plasma clouds about spacecraft are still active research areas. To adequately evaluate these and other effects the NEPSTP science program includes a dedicated effort to assess Thruster Performance and to conduct a number of so called 'Operational Experiments' to evaluate unresolved aspects of the NEP environment. This paper will review our planned efforts.

  13. Conceptual design, evaluation and research identification for Remote Augmented Propulsive Lift Systems (RALS) with ejectors for VTOL aircraft

    NASA Technical Reports Server (NTRS)

    Willis, W. S.; Konarski, M.; Sutherland, M. V.

    1982-01-01

    Ejector concepts for use with a remote augmented lift system (RALS) exhaust nozzle were studied. A number of concepts were considered and three were selected as having the greatest promise of providing the desired aircraft and exhaust gas cooling and lift enhancement. A scale model test program is recommended to explore the effects of the more important parameters on ejector performance.

  14. Space Propulsion Technology Program Overview

    NASA Technical Reports Server (NTRS)

    Escher, William J. D.

    1991-01-01

    The topics presented are covered in viewgraph form. Focused program elements are: (1) transportation systems, which include earth-to-orbit propulsion, commercial vehicle propulsion, auxiliary propulsion, advanced cryogenic engines, cryogenic fluid systems, nuclear thermal propulsion, and nuclear electric propulsion; (2) space platforms, which include spacecraft on-board propulsion, and station keeping propulsion; and (3) technology flight experiments, which include cryogenic orbital N2 experiment (CONE), SEPS flight experiment, and cryogenic orbital H2 experiment (COHE).

  15. Integrated Pressure-Fed Liquid Oxygen / Methane Propulsion Systems - Morpheus Experience, MARE, and Future Applications

    NASA Technical Reports Server (NTRS)

    Hurlbert, Eric; Morehead, Robert; Melcher, John C.; Atwell, Matt

    2016-01-01

    An integrated liquid oxygen (LOx) and methane propulsion system where common propellants are fed to the reaction control system and main engines offers advantages in performance, simplicity, reliability, and reusability. LOx/Methane provides new capabilities to use propellants that are manufactured on the Mars surface for ascent return and to integrate with power and life support systems. The clean burning, non-toxic, high vapor pressure propellants provide significant advantages for reliable ignition in a space vacuum, and for reliable safing or purging of a space-based vehicle. The NASA Advanced Exploration Systems (AES) Morpheus lander demonstrated many of these key attributes as it completed over 65 tests including 15 flights through 2014. Morpheus is a prototype of LOx/Methane propellant lander vehicle with a fully integrated propulsion system. The Morpheus lander flight demonstrations led to the proposal to use LOx/Methane for a Discovery class mission, named Moon Aging Regolith Experiment (MARE) to land an in-situ science payload for Southwest Research Institute on the Lunar surface. Lox/Methane is extensible to human spacecraft for many transportation elements of a Mars architecture. This paper discusses LOx/Methane propulsion systems in regards to trade studies, the Morpheus project experience, the MARE NAVIS (NASA Autonomous Vehicle for In-situ Science) lander, and future possible applications. The paper also discusses technology research and development needs for Lox/Methane propulsion systems.

  16. [Bladder augmentation in children: experience with 15 cases].

    PubMed

    Nortes, L; Zambudio, G A

    1996-07-01

    From 1993 to 1995 bladder augmentation was performed in 11 female and 4 male patients from 1 to 13 years old (average age 6.7 years). Indications included neurogenic bladder, extrophy and epispadias with small bladder. A ventriculoperitoneal shunt had been performed in 6 patients for hydrocephalus. We used 22 segments since 5 patients had 2 segments. Segments included sigmoid in 12 cases, stomach in 5, small bowel in 1, cecum and appendix in 2. We have used the AMS-800 artificial urinary sphincter in 7 patients. Upper tracts and renal function have remained stable in these patients. Continence was achieved in 7 of 9 cases with augmentation, and in 6 of those patients with artificial urinary sphincter. The most common complication was leaks and the hematuria-dysuria syndrome when stomach was used.

  17. Dedicated Laboratory Setup for CO{sub 2} TEA Laser Propulsion Experiments at Rensselaer Polytechnic Institute

    SciTech Connect

    Salvador, Israel I.; Kenoyer, David; Myrabo, Leik N.; Notaro, Samuel

    2010-10-08

    Laser propulsion research progress has traditionally been hindered by the scarcity of photon sources with desirable characteristics, as well as integrated specialized flow facilities in a dedicated laboratory environment. For TEA CO{sub 2} lasers, the minimal requirements are time-average powers of >100 W), and pulse energies of >10 J pulses with short duration (e.g., 0.1 to 1 {mu}s); furthermore, for the advanced pulsejet engines of interest here, the laser system must simulate pulse repetition frequencies of 1-10 kilohertz or more, at least for two (carefully sequenced) pulses. A well-equipped laser propulsion laboratory should have an arsenal of sensor and diagnostics tools (such as load cells, thrust stands, moment balances, pressure and heat transfer gages), Tesla-level electromagnet and permanent magnets, flow simulation facilities, and high-speed visualization systems, in addition to other related equipment, such as optics and gas supply systems. In this paper we introduce a cutting-edge Laser Propulsion Laboratory created at Rensselaer Polytechnic Institute, one of the very few in the world to be uniquely set up for beamed energy propulsion (BEP) experiments. The present BEP research program is described, along with the envisioned research strategy that will exploit current and expanded facilities in the near future.

  18. Dedicated Laboratory Setup for CO2 TEA Laser Propulsion Experiments at Rensselaer Polytechnic Institute

    NASA Astrophysics Data System (ADS)

    Salvador, Israel I.; Kenoyer, David; Myrabo, Leik N.; Notaro, Samuel

    2010-10-01

    Laser propulsion research progress has traditionally been hindered by the scarcity of photon sources with desirable characteristics, as well as integrated specialized flow facilities in a dedicated laboratory environment. For TEA CO2 lasers, the minimal requirements are time-average powers of >100 W), and pulse energies of >10 J pulses with short duration (e.g., 0.1 to 1 μs); furthermore, for the advanced pulsejet engines of interest here, the laser system must simulate pulse repetition frequencies of 1-10 kilohertz or more, at least for two (carefully sequenced) pulses. A well-equipped laser propulsion laboratory should have an arsenal of sensor and diagnostics tools (such as load cells, thrust stands, moment balances, pressure and heat transfer gages), Tesla-level electromagnet and permanent magnets, flow simulation facilities, and high-speed visualization systems, in addition to other related equipment, such as optics and gas supply systems. In this paper we introduce a cutting-edge Laser Propulsion Laboratory created at Rensselaer Polytechnic Institute, one of the very few in the world to be uniquely set up for beamed energy propulsion (BEP) experiments. The present BEP research program is described, along with the envisioned research strategy that will exploit current and expanded facilities in the near future.

  19. Arc-heated gas flow experiments for hypersonic propulsion applications

    NASA Astrophysics Data System (ADS)

    Roseberry, Christopher Matthew

    Although hydrogen is an attractive fuel for a hypersonic air-breathing vehicle in terms of reaction rate, flame temperature, and energy content per unit mass, the substantial tank volume required to store hydrogen imposes a drag penalty to performance that tends to offset these advantages. An alternative approach is to carry a hydrocarbon fuel and convert it on-board into a hydrogen-rich gas mixture to be injected into the engine combustors. To investigate this approach, the UTA Arc-Heated Wind Tunnel facility was modified to run on methane rather than the normally used nitrogen. Previously, this facility was extensively developed for the purpose of eventually performing experiments simulating scramjet engine flow along a single expansion ramp nozzle (SERN) in addition to more generalized applications. This formidable development process, which involved modifications to every existing subsystem along with the incorporation of new subsystems, is described in detail. Fortunately, only a minor plumbing reconfiguration was required to prepare the facility for the fuel reformation research. After a failure of the arc heater power supply, a 5.6 kW plasma-cutting torch was modified in order to continue the arc pyrolysis experiments. The outlet gas flow from the plasma torch was sampled and subsequently analyzed using gas chromatography. The experimental apparatus converted the methane feedstock almost completely into carbon, hydrogen and acetylene. A high yield of hydrogen, consisting of a product mole fraction of roughly 0.7, was consistently obtained. Unfortunately, the energy consumption of the apparatus was too excessive to be feasible for a flight vehicle. However, other researchers have pyrolyzed hydrocarbons using electric arcs with much less power input per unit mass.

  20. Rotational Augmentation Disparities in the MEXICO and UAE Phase VI Experiments: Preprint

    SciTech Connect

    Schreck, S.; Sant, T.; Micallef, D.

    2010-05-01

    Wind turbine structures and components suffer excessive loads and premature failures when key aerodynamic phenomena are not well characterized, fail to be understood, or are inaccurately predicted. Turbine blade rotational augmentation remains incompletely characterized and understood, thus limiting robust prediction for design. Pertinent rotational augmentation research including experimental, theoretical, and computational work has been pursued for some time, but large scale wind tunnel testing is a relatively recent development for investigating wind turbine blade aerodynamics. Because of their large scale and complementary nature, the MEXICO and UAE Phase VI wind tunnel experiments offer unprecedented synergies to better characterize and understand rotational augmentation of blade aerodynamics.

  1. The effects of experience on the energy cost of wheelchair propulsion.

    PubMed

    Croft, L; Lenton, J; Tolfrey, K; Goosey-Tolfrey, V

    2013-12-01

    Gross mechanical efficiency (GE) of experienced wheelchair users is significantly higher than novice able-bodied individuals suggesting energy expenditure (EE) may be reduced in experienced individuals. With knowledge of the energy expended during wheelchair propulsion, nutritional recommendations can be provided for individuals in their early stages of rehabilitation and for habituated wheelchair users. To investigate the effects of experience on EE during wheelchair propulsion at fixed power outputs (PO's). This was an experimental study. The experiment was conducted in a controlled University laboratory. Thirty-one individuals took part in this study. Participants were assigned to a group in accordance to their wheelchair propulsion experience: 1) novice able-bodied individuals (NOV; N.=11), 2) able-bodied individuals habituated to three weeks practice (PRAC; N.=11) and 3) experienced paraplegic daily-wheelchair users (EXP; N.=9). Oxygen uptake, EE, GE% and HR were measured during wheelchair propulsion on a motorised treadmill at 10, 18 and 26 W. Energy expenditure analysis revealed a significant main effect of PO and group (P<0.01) and a significant group by PO interaction (P<0.01). Follow-up pair-wise comparisons revealed significantly lower EE in EXP compared to both other groups (P<0.01), but no difference was shown between NOV and PRAC (P=0.15). A lower relative EE of 20, 22 and 32% was reported in the EXP group compared to the NOV group at 10, 18 and 26 W respectively. In comparison to the PRAC group, the EE of the EXP group was 10, 16 and 26% lower in relative terms at the same PO's respectively. The EXP expended less EE compared to both NOV and PRAC. This finding has great implications for nutritionists and health care professionals working in the field of physical activity and weight management since the EE is influenced by experience.

  2. Wheelchair propulsion: effects of experience and push strategy on efficiency and perceived exertion.

    PubMed

    Lenton, John P; Fowler, Neil E; van der Woude, Lucas; Goosey-Tolfrey, Victoria L

    2008-10-01

    The purpose of this study was to examine the role of wheeling experience on efficiency, metabolic cost, and differentiated ratings of perceived exertion (RPEs) during synchronous and asynchronous hand-rim propulsion with varying arm frequencies. Fourteen able-bodied (AB) male participants and 8 male wheelchair sportsmen (WS) performed tests of peak oxygen consumption for both propulsion modes. Subsequently, 2 series of five 4-min sub-maximal exercise bouts were completed at an individualized velocity (60% of peak oxygen consumption). Arm frequencies consisted of the freely chosen frequency (FCF), followed by 4 counter-balanced paced trials pushing at 60%, 80%, 120%, and 140% of the FCF. Efficiency indices (gross, GE; work, WE) were determined and peripheral (RPE-P), central (RPE-C), and overall (RPE-O) RPEs were recorded. The GE (6.4% vs. 8.4%) and WE (11.3% vs. 15.1%) were significantly higher in WS than in AB (p = 0.001). Trends in the oxygen consumption, GE, and WE data were similar in both groups, propulsion mode, and arm frequency. Data suggest that 80% FCF resulted in improved efficiency for both propulsion mode and group, although the differences between those arm frequencies immediately above and below were non-significant. Lower RPE scores corresponded with higher efficiency values. Regardless of group there were significant differences (p = 0.001) between the differentiated RPE measures, whereby RPE-P was on average always the highest score (13.1) and RPE-C the lowest (11.1; RPE-O was 12.2). In conclusion, despite the anticipated differences in efficiency between the WS and AB participants, this study confirmed that psycho-physiological measures produce similar trends to physiological measures with manipulations of both arm frequency and propulsion mode.

  3. The experience of new sensorimotor contingencies by sensory augmentation

    PubMed Central

    Kaspar, Kai; König, Sabine; Schwandt, Jessika; König, Peter

    2014-01-01

    Embedded in the paradigm of embodied cognition, the theory of sensorimotor contingencies (SMCs) proposes that motor actions and associated sensory stimulations are tied together by lawful relations termed SMCs. We aimed to investigate whether SMCs can be learned by means of sensory augmentation. Therefore we focused on related perceptual changes. Subjects trained for 7 weeks with the feelSpace belt mapping information of the magnetic north to vibrotactile stimulation around the waist. They experienced substantial changes in their space perception. The belt facilitated navigation and stimulated the usage of new navigation strategies. The belt’s vibrating signal changed to a kind of spatial information over time while the belt’s appeal and perceived usability increased. The belt also induced certain emotional states. Overall, the results show that learning new SMCs with this relatively small and usable device leads to profound perceptual and emotional changes, which are fully compatible with embodied theories of cognition. PMID:25038534

  4. The MPD arcjet thruster system for Electric Propulsion Experiment onboard Space Flyer Unit

    NASA Astrophysics Data System (ADS)

    Toki, Kyoichiro; Shimizu, Yukio; Kuriki, Kyoichi; Suzuki, Hiroshi; Kunii, Yoshinori

    The Electric Propulsion Experiment (EPEX) will be tested in the Space Flyer Unit Mission One (SFU-1) as the first space-flown hydrazine MPD arcjet thruster system in the world. The development was continued after the breadboard model system endurance test in 1988 to start the engineering model fabrication/test. Presently the components of EPEX are scheduled to be integrated in a Payload Unit (PLU) box together with two other experiments in order to dedicate them to a system integration test following several environment tests.

  5. Experiment Design for Complex VTOL Aircraft with Distributed Propulsion and Tilt Wing

    NASA Technical Reports Server (NTRS)

    Murphy, Patrick C.; Landman, Drew

    2015-01-01

    Selected experimental results from a wind tunnel study of a subscale VTOL concept with distributed propulsion and tilt lifting surfaces are presented. The vehicle complexity and automated test facility were ideal for use with a randomized designed experiment. Design of Experiments and Response Surface Methods were invoked to produce run efficient, statistically rigorous regression models with minimized prediction error. Static tests were conducted at the NASA Langley 12-Foot Low-Speed Tunnel to model all six aerodynamic coefficients over a large flight envelope. This work supports investigations at NASA Langley in developing advanced configurations, simulations, and advanced control systems.

  6. Explore and experience: mobile augmented reality for medical training.

    PubMed

    Albrecht, Urs-Vito; Noll, Christoph; von Jan, Ute

    2013-01-01

    In medicine, especially in basic education, it may sometimes be inappropriate to integrate real patients into classes due to ethical issues that must be avoided. Nevertheless, the quality of medical education may suffer without the use of real cases. This is especially true of medical specialties such as legal medicine: survivors of a crime are already subjected to procedures that constitute a severe emotional burden and may cause additional distress even without the added presence of students. Using augmented reality based applications may alleviate this ethical dilemma by giving students the possibility to practice the necessary skills based on virtual but nevertheless almost realistic cases. The app "mARble®" that is presented in this paper follows this approach. The currently available learning module for legal medicine gives users an opportunity to learn about various wound patterns by virtually overlaying them on their own skin and is applicable in different learning settings. Preliminary evaluation results covering learning efficiency and emotional components of the learning process are promising. Content modules for other medical specialtiesare currently under construction.

  7. The experience of new sensorimotor contingencies by sensory augmentation.

    PubMed

    Kaspar, Kai; König, Sabine; Schwandt, Jessika; König, Peter

    2014-08-01

    Embedded in the paradigm of embodied cognition, the theory of sensorimotor contingencies (SMCs) proposes that motor actions and associated sensory stimulations are tied together by lawful relations termed SMCs. We aimed to investigate whether SMCs can be learned by means of sensory augmentation. Therefore we focused on related perceptual changes. Subjects trained for 7 weeks with the feelSpace belt mapping information of the magnetic north to vibrotactile stimulation around the waist. They experienced substantial changes in their space perception. The belt facilitated navigation and stimulated the usage of new navigation strategies. The belt's vibrating signal changed to a kind of spatial information over time while the belt's appeal and perceived usability increased. The belt also induced certain emotional states. Overall, the results show that learning new SMCs with this relatively small and usable device leads to profound perceptual and emotional changes, which are fully compatible with embodied theories of cognition. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Flight Experiments On Energy Scaling For In-Space Laser Propulsion

    SciTech Connect

    Scharring, Stefan; Eckel, Hans-Albert; Wollenhaupt, Eric; Roeser, Hans-Peter

    2010-05-06

    As a preparatory study on space-borne laser propulsion, flight experiments with a parabolic thruster were carried out on an air cushion table. The thruster was mounted like a sail on a puck, allowing for laser-driven motion in three degrees of freedom (3 DOF) in artificial weightlessness. Momentum coupling is derived from point explosion theory for various parabolic thruster geometries with respect to energy scaling issues. The experimental data are compared with theoretical predictions and with results from vertical free flights. Experimental results for the air-breakdown threshold and POM ablation inside the thruster are compared with fluence data from beam propagation modeling.

  9. Experience with Formal Methods techniques at the Jet Propulsion Laboratory from a quality assurance perspective

    NASA Technical Reports Server (NTRS)

    Kelly, John C.; Covington, Rick

    1993-01-01

    Recent experience with Formal Methods (FM) in the Software Quality Assurance Section at the Jet Propulsion Lab is presented. An integrated Formal Method process is presented to show how related existing requirements analysis and FM techniques complement one another. Example application of FM techniques such as formal specifications and specification animators are presented. The authors suggest that the quality assurance organization is a natural home for the Formal Methods specialist, whose expertise can then be used to best advantage across a range of projects.

  10. The energetics of hydrogen atom recombination - Analysis, experiments, and modeling. [in electrothermal propulsion system

    NASA Technical Reports Server (NTRS)

    Filpus, J. W.; Hawley, M. C.

    1984-01-01

    A theoretical investigation of the effect of the microscopic energetics of the recombination reaction on the performance of a microwave-plasma electrothermal propulsion system is described, and the results of the analysis are presented. A series of experiments to test the concept is described and analyzed by comparison with a computer model of the recombination reaction. It is concluded that internal energy considerations are not likely to significantly affect the design of a microwave-plasma electrothermal rocket. The experimental results indicate that the microwave power is far higher than the capacity of the gas to absorb it; the cooling needed to control the energy dominates the experimental results.

  11. Experience with Formal Methods techniques at the Jet Propulsion Laboratory from a quality assurance perspective

    NASA Technical Reports Server (NTRS)

    Kelly, John C.; Covington, Rick

    1993-01-01

    Recent experience with Formal Methods (FM) in the Software Quality Assurance Section at the Jet Propulsion Lab is presented. An integrated Formal Method process is presented to show how related existing requirements analysis and FM techniques complement one another. Example application of FM techniques such as formal specifications and specification animators are presented. The authors suggest that the quality assurance organization is a natural home for the Formal Methods specialist, whose expertise can then be used to best advantage across a range of projects.

  12. Integration and diagnostics for the US air force phillips laboratory Electric Propulsion Space Experiment (ESEX)

    NASA Astrophysics Data System (ADS)

    Leduc, J. R.; Sutton, A. M.; Bromaghim, D. R.

    1997-01-01

    The Electric Propulsion Space Experiment (ESEX) comprises a 30 kW ammonia arcjet system, on-board diagnostics, and a remote observations program. A scientific plan encompassing implementation, operation, and data analysis has been developed. Onboard instruments will provide accurate measurements of spacecraft acceleration, thruster operating characteristics, performance, radiated thermal loads, and will document arcjet operation through filtered imagery. Instruments will also provide upper limits for spacecraft contamination and communications band electromagnetic interference. Remote observations will accurately characterize high-rate communications links and will determine the arcjet optical and RF signatures.

  13. `Galileo Galilei' flight experiment on the equivalence principle with field emission electric propulsion

    NASA Astrophysics Data System (ADS)

    Nobili, Anna M.; Bramanti, Donato; Catastini, Giuseppe

    1996-11-01

    An experiment to test the equivalence of inertial to gravitational (passive) mass in space offers two main advantages: a signal about a factor of a thousand larger than on Earth and the possibility of exploiting the absence of weight. `Galileo Galilei' (GG) is a small satellite mission currently under study in Italy with the financial support of ASI (Agenzia Spaziale Italiana). The mission concerns a small, low Earth satellite (0264-9381/13/11A/028/img1 total mass, 0264-9381/13/11A/028/img2 altitude) with two objectives. One is scientific, in the field of fundamental physics, and the other technological within the framework of spacecraft propulsion and drag compensation. The scientific goal is to test the equivalence principle to one part in 0264-9381/13/11A/028/img3, four orders of magnitude better than the best ground results. The technological goal is a full, comprehensive test of FEEP (field emission electric propulsion) thrusters for accurate drag compensation, a technology developed in Europe by the ESA (European Space Agency) which is likely to become an essential component of all space experiments which require measurement of small forces. The GG experiment is based on novel concepts and does not require low temperatures.

  14. A disturbance isolation controller for the solar electric propulsion system flight experiment

    NASA Technical Reports Server (NTRS)

    Waites, H. B.

    1982-01-01

    A disturbance isolation controller (DIC) is developed for a simplified model of the solar electric propulsion system (SEPS) flight experiment which consists of a rigid Sperry gimbal torquer (AGS) mounted to a rigid orbiter and the SEPS solar array (rigid) end mounted to the AGS. The main purpose of the DIC is to reduce the effects of orbiter disturbances which are transmitted to the flight experiment. The DIC uses an observer, which does not require the direct measurement of the plant inputs, to obtain estimates of the plant states and the rate of the plant states. The state and rate of state information is used to design a controller which isolates disturbances from specified segments of the plant, and for the flight experiment, the isolated segment is the SEPS solar array.

  15. Development of control and monitor subsystem for electric propulsion experiment onboard Space Flyer Unit (SFU)

    SciTech Connect

    Kunii, Y.; Moriai, T.; Okamura, T.; Yoshida, T.; Ijichi, K.

    1987-05-01

    The Electric Propulsion Experiment (EPEX) is a Japanese space experiment program for the quasi-steady MPD thruster system. The EPEX is planned to be tested on a Japanese free flying platform and launched in the 1990s. The requirements for the control and monitor subsystem of EPEX were discussed and the conceptual design was performed. Since 1983, repetitive charging and discharging operations for the ground endurance tests were conducted with the sequence controllers, which were made of hard wired logic circuits. Photo transistors were found to be preferable for recognition of the occurance of arc discharge and the normal termination of the repetitive cycle. For the EPEX, because of the limited capability of the platform bus system, the autonomous operation of the experiment is required in addition to the simple sequence control. The autonomous operation with a microcomputer system will be tested in the next ground endurance test to be started in October 1987.

  16. Intravascular micropump for augmented liver perfusion: first in vivo experience.

    PubMed

    Havlík, R; Kerkhoffs, W; Jiao, L R; Schumacher, O; Reul, H; Habib, N

    2001-05-01

    The aim of this study was to assess the in vivo performance of a new microaxial rotary blood pump developed for long-term intraportal implantation. The pump, measuring 7 mm in diameter, has a single stage impeller and is powered by a microelectric motor. The pump was implanted into the portal vein in 13 large white pigs under general anesthesia. All animals recovered after the portal pump implantation, and they were observed until the pump failed. The 2 longest running pumps performed for 40 and 36 h, respectively. Either thrombus formation or technical problems, especially in the bearings, were the main causes of pump failure during the experiment. No local or systemic adverse effects were observed during the portal pumping period. Full recovery of the animals following intraportal pump implantation was achieved. However, further technical improvements to the pump are required to maintain a longer performance in vivo.

  17. Linear Aerospike SR-71 Experiment (LASRE): Aerospace Propulsion Hazard Mitigation Systems

    NASA Technical Reports Server (NTRS)

    Mizukami, Masashi; Corpening, Griffin P.; Ray, Ronald J.; Hass, Neal; Ennix, Kimberly A.; Lazaroff, Scott M.

    1998-01-01

    A major hazard posed by the propulsion system of hypersonic and space vehicles is the possibility of fire or explosion in the vehicle environment. The hazard is mitigated by minimizing or detecting, in the vehicle environment, the three ingredients essential to producing fire: fuel, oxidizer, and an ignition source. The Linear Aerospike SR-71 Experiment (LASRE) consisted of a linear aerospike rocket engine integrated into one-half of an X-33-like lifting body shape, carried on top of an SR-71 aircraft. Gaseous hydrogen and liquid oxygen were used as propellants. Although LASRE is a one-of-a-kind experimental system, it must be rated for piloted flight, so this test presented a unique challenge. To help meet safety requirements, the following propulsion hazard mitigation systems were incorporated into the experiment: pod inert purge, oxygen sensors, a hydrogen leak detection algorithm, hydrogen sensors, fire detection and pod temperature thermocouples, water misting, and control room displays. These systems are described, and their development discussed. Analyses, ground test, and flight test results are presented, as are findings and lessons learned.

  18. Aerodynamic Database Development for the Hyper-X Airframe Integrated Scramjet Propulsion Experiments

    NASA Technical Reports Server (NTRS)

    Engelund, Walter C.; Holland, Scott D.; Cockrell, Charles E., Jr.; Bittner, Robert D.

    2000-01-01

    This paper provides an overview of the activities associated with the aerodynamic database which is being developed in support of NASA's Hyper-X scramjet flight experiments. Three flight tests are planned as part of the Hyper-X program. Each will utilize a small, nonrecoverable research vehicle with an airframe integrated scramjet propulsion engine. The research vehicles will be individually rocket boosted to the scramjet engine test points at Mach 7 and Mach 10. The research vehicles will then separate from the first stage booster vehicle and the scramjet engine test will be conducted prior to the terminal decent phase of the flight. An overview is provided of the activities associated with the development of the Hyper-X aerodynamic database, including wind tunnel test activities and parallel CFD analysis efforts for all phases of the Hyper-X flight tests. A brief summary of the Hyper-X research vehicle aerodynamic characteristics is provided, including the direct and indirect effects of the airframe integrated scramjet propulsion system operation on the basic airframe stability and control characteristics. Brief comments on the planned post flight data analysis efforts are also included.

  19. Propulsion control experience used in the Highly Integrated Digital Electronic Control (HIDEC) program

    NASA Technical Reports Server (NTRS)

    Myers, L. P.; Burcham, F. W., Jr.

    1984-01-01

    The highly integrated digital electronic control (HIDEC) program will integrate the propulsion and flight control systems on an F-15 airplane at NASA Ames Research Center's Dryden Flight Research Facility. Ames-Dryden has conducted several propulsion control programs that have contributed to the HIDEC program. The digital electronic engine control (DEEC) flight evaluation investigated the performance and operability of the F100 engine equipped with a full-authority digital electronic control system. Investigations of nozzle instability, fault detection and accommodation, and augmentor transient capability provided important information for the HIDEC program. The F100 engine model derivative (EMD) was also flown in the F-15 airplane, and airplane performance was significantly improved. A throttle response problem was found and solved with a software fix to the control logic. For the HIDEC program, the F100 EMD engines equipped with DEEC controls will be integrated with the digital flight control system. The control modes to be implemented are an integrated flightpath management mode and an integrated adaptive engine control system mode. The engine control experience that will be used in the HIDEC program is discussed.

  20. Moment generation in wheelchair propulsion.

    PubMed

    Guo, Lan-Yuen; Zhao, K D; Su, Fong-Chin; An, Kai-Nan

    2003-01-01

    Wheelchair propulsion is a man machine interaction in which chair design and fit affect the relative positions and orientations of the upper extremity relative to the handrim and wheel axle. To understand these relationships better, experimental data were collected in five hand positions from five subjects exerting maximal effort to propel an instrumented wheelchair with its wheel in a locked position. The results of experiments revealed that the progression moment was greater at both initial and terminal propulsion positions and smaller in the mid-propulsion position. The vertical and horizontal force components were directed radially away from the wheel axle posterior to the dead centre position and radially towards the wheel axle anterior to top dead centre. Subsequently, a subject-specific quasi-static model of the upper extremity which maximized wheel progression moment was developed to augment our understanding of experimental measures. Model-predicted trends in progression moments and hand force direction were similar to experiment. Model predictions revealed that the optimal progression moment generation could potentially be affected by an individual's anthropometric parameters, joint strengths and also the direction of force applied by the hand on the handrim. Through wheelchair fitting and training of wheelchair users, it may be possible to improve propulsion technique.

  1. Air Augmented Rocket Propulsion Concepts

    DTIC Science & Technology

    1988-04-01

    vs. Passive Cooling Weight Tradeoffs 120 Figure 85 RBCC/SSTO Vehicle System Work Breakdown Structure 121 Figure 86 Hierarchical Relationship Between a...an initial characterization of the engine systems and the vehicle configurations to be used. In Task 5, quantitative information required to design an...analytical tools required to analyze vehicle system perforrmace in orbital missions and to characterize the sizing, mass characteristics and vehicle

  2. Estimation of Uncertainties for a Supersonic Retro-Propulsion Model Validation Experiment in a Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Rhode, Matthew N.; Oberkampf, William L.

    2012-01-01

    A high-quality model validation experiment was performed in the NASA Langley Research Center Unitary Plan Wind Tunnel to assess the predictive accuracy of computational fluid dynamics (CFD) models for a blunt-body supersonic retro-propulsion configuration at Mach numbers from 2.4 to 4.6. Static and fluctuating surface pressure data were acquired on a 5-inch-diameter test article with a forebody composed of a spherically-blunted, 70-degree half-angle cone and a cylindrical aft body. One non-powered configuration with a smooth outer mold line was tested as well as three different powered, forward-firing nozzle configurations: a centerline nozzle, three nozzles equally spaced around the forebody, and a combination with all four nozzles. A key objective of the experiment was the determination of experimental uncertainties from a range of sources such as random measurement error, flowfield non-uniformity, and model/instrumentation asymmetries. This paper discusses the design of the experiment towards capturing these uncertainties for the baseline non-powered configuration, the methodology utilized in quantifying the various sources of uncertainty, and examples of the uncertainties applied to non-powered and powered experimental results. The analysis showed that flowfield nonuniformity was the dominant contributor to the overall uncertainty a finding in agreement with other experiments that have quantified various sources of uncertainty.

  3. [Effects of acute hypobaric hypoxia on gastric emptying and intestinal propulsion: experiment with rats].

    PubMed

    Yang, Chun-min; Chen, Ying; Mao, Gao-ping; Ma, Lu-na; Wang, Zhe; Zhang, Ying-hui

    2006-09-12

    To investigate the impact of acute hypobaric hypoxia on the gastrointestinal motility. Eighty Wistar rats were randomly divided into 4 equal groups to be fed with (99)Tc(m)-labeled test food: ground level control group, put in the hypobaric chamber for 30 minutes; 3000 m simulated altitude group, exposed to the environment of simulated altitude of 3000 m for 30 minutes; 5000 m simulated altitude group, exposed to the environment of simulated altitude of 5000 m for 30 minutes; and mosapride + 5000 m simulated altitude group, fed with mosapride 2 mg/kg by perfusing stomach and fed with isotope-labeled test food 30 minutes later, and then exposed to 5000 m simulated altitude for 30 minutes. By the end of experiment the rats were killed, their stomachs were taken out to calculate the gastric emptying rate. Their intestine from pylorus to ileocecum was taken out to measure the intestinal propulsion function by using charcoal particle method. At the beginning and at the end of experiment abdominal arterial blood samples were collected to detect the plasma motilin and nitric oxide (NO) concentrations. The gastric emptying rate of the 5000 m simulated altitude group was 41% +/- 10%, significantly lower than that of the ground level group (62% +/- 12%, P < 0.01), and the charcoal transit rate of the 5000 m simulated altitude group was 37% +/- 8%, significantly lower than that of the ground level group (61% +/- 13%, P < 0.01). The gastric emptying rate and intestine propulsion rate of the 3000 m simulated altitude group were not significantly different from those of the ground level group. The gastric emptying rate of the mosapride + 5000 m simulated altitude group was 55% +/- 12%, significantly higher than that of the 5000 m simulated altitude group (P < 0.05), however, the intestine propulsion rate of the mosapride + 5000 m simulated altitude group was not significantly different from that of the 5000 m simulated altitude group (P > 0.05). The plasma motilin level of the

  4. Experience with Data Science as an Intern with the Jet Propulsion Laboratory

    NASA Astrophysics Data System (ADS)

    Whittell, J.; Mattmann, C. A.; Whitehall, K. D.; Ramirez, P.; Goodale, C. E.; Boustani, M.; Hart, A. F.; Kim, J.; Waliser, D. E.; Joyce, M. J.

    2013-12-01

    The Regional Climate Model Evaluation System (RCMES, http://rcmes.jpl.nasa.gov) at NASA's Jet Propulsion Laboratory seeks to improve regional climate model output by comparing past model predictions with Earth-orbiting satellite data (Mattmann et al. 2013). RCMES ingests satellite and RCM data and processes these data into a common format; as needed, the software queries the RCMES database for these datasets, on which it runs a series of statistical metrics including model-satellite comparisons. The development of the RCMES software relies on collaboration between climatologists and computer scientists, as evinced by RCMES longstanding work with CORDEX (Kim et al. 2012). Over a total of 17 weeks in 2011, 2012, and 2013, I worked as an intern at NASA's Jet Propulsion Laboratory in a supportive capacity for RCMES. A high school student, I had no formal background in either Earth science or computer technology, but was immersed in both fields. In 2011, I researched three earth-science data management projects, producing a high-level explanation of these endeavors. The following year, I studied Python, contributing a command-line user interface to the RCMES project code. In 2013, I assisted with data acquisition, wrote a file header information plugin, and the visualization tool GrADS. The experience demonstrated the importance of an interdisciplinary approach to data processing: to streamline data ingestion and processing, scientists must understand, at least on a high-level, any programs they might utilize while to best serve the needs of earth scientists, software engineers must understand the science behind the data they handle.

  5. Technical experience from clinical studies with INPRES and a concept for a miniature augmented reality system

    NASA Astrophysics Data System (ADS)

    Sudra, Gunther; Marmulla, Ruediger; Salb, Tobias; Gockel, Tilo; Eggers, Georg; Giesler, Bjoern; Ghanai, Sassan; Fritz, Dominik; Dillmann, Ruediger; Muehling, Joachim

    2005-04-01

    This paper is going to present a summary of our technical experience with the INPRES System -- an augmented reality system based upon a tracked see-through head-mounted display. With INPRES a complete augmented reality solution has been developed that has crucial advantages when compared with previous navigation systems. Using these techniques the surgeon does not need to turn his head from the patient to the computer monitor and vice versa. The system's purpose is to display virtual objects, e.g. cutting trajectories, tumours and risk-areas from computer-based surgical planning systems directly in the surgical site. The INPRES system was evaluated in several patient experiments in craniofacial surgery at the Department of Oral and Maxillofacial Surgery/University of Heidelberg. We will discuss the technical advantages as well as the limitations of INPRES and present two strategies as a result. On the one hand we will improve the existing and successful INPRES system with new hardware and a new calibration method to compensate for the stated disadvantage. On the other hand we will focus on miniaturized augmented reality systems and present a new concept based on fibre optics. This new system should be easily adaptable at surgical instruments and capable of projecting small structures. It consists of a source of light, a miniature TFT display, a fibre optic cable and a tool grip. Compared to established projection systems it has the capability of projecting into areas that are only accessible by a narrow path. No wide surgical exposure of the region is necessary for the use of augmented reality.

  6. Thermal Design and Flight Experience of the Mars Exploration Rover Spacecraft Computer-Controlled, Propulsion Line Heaters

    NASA Technical Reports Server (NTRS)

    Novak, Keith S.; Kinsella, Gary M; Krylo, Robert J.; Sunada, Eric T.

    2004-01-01

    This paper covers the design, thermal testing and flight experiences with the computer-controlled thermostats on the propulsion line heaters. Flight experience revealed heater control behavior with propellant loaded into the system and during thruster firings that was not observable during system level testing. Explanations of flight behavior, lessons learned, and suggestions for improvement of the propellant line heater design are presented in this paper.

  7. Thermal Design and Flight Experience of the Mars Exploration Rover Spacecraft Computer-Controlled, Propulsion Line Heaters

    NASA Technical Reports Server (NTRS)

    Novak, Keith S.; Kinsella, Gary M; Krylo, Robert J.; Sunada, Eric T.

    2004-01-01

    This paper covers the design, thermal testing and flight experiences with the computer-controlled thermostats on the propulsion line heaters. Flight experience revealed heater control behavior with propellant loaded into the system and during thruster firings that was not observable during system level testing. Explanations of flight behavior, lessons learned, and suggestions for improvement of the propellant line heater design are presented in this paper.

  8. Laboratory Facilities and Measurement Techniques for Beamed-Energy-Propulsion Experiments in Brazil

    NASA Astrophysics Data System (ADS)

    de Oliveira, Antonio Carlos; Chanes Júnior, José Brosler; Cordeiro Marcos, Thiago Victor; Pinto, David Romanelli; Santos Vilela, Renan Guilherme; Barros Galvão, Victor Alves; Mantovani, Arthur Freire; da Costa, Felipe Jean; dos Santos Assenção, José Adeildo; dos Santos, Alberto Monteiro; de Paula Toro, Paulo Gilberto; Sala Minucci, Marco Antonio; da Silveira Rêgo, Israel; Salvador, Israel Irone; Myrabo, Leik N.

    2011-11-01

    Laser propulsion is an innovative concept of accessing the space easier and cheaper where the propulsive energy is beamed to the aerospace vehicle in flight from ground—or even satellite-based high-power laser sources. In order to be realistic about laser propulsion, the Institute for Advanced Studies of the Brazilian Air Force in cooperation with the United States Air Force and the Rensselaer Polytechnic Institute are seriously investigating its basic physics mechanisms and engineering aspects at the Henry T. Hamamatsu Laboratory of Hypersonic and Aerothermodynamics in São José dos Campos, Brazil. This paper describes in details the existing facilities and measuring systems such as high-power laser devices, pulsed-hypersonic wind tunnels and high-speed flow visualization system currently utilized in the laboratory for experimentation on laser propulsion.

  9. Advanced propulsion on a shoestring

    SciTech Connect

    Lerner, E.J.

    1990-05-01

    Consideration is given to propulsion concepts under study by NASA Advanced Propulsion Research Program. These concepts include fusion, antimatter-matter annihilation, microwave electrothermal, and electron cyclotron resonance propulsion. Results from programs to develop fusion technologies are reviewed, including compact fusion devices and inertial confinement experiments. Problems concerning both antimatter and fusion propulsion concepts are examined and the economic issues related to propulsion research are discussed.

  10. Solid propulsion advanced concepts

    NASA Technical Reports Server (NTRS)

    Nakamura, Y.; Shafer, J. I.

    1972-01-01

    The feasibility and application of a solid propulsion powered spacecraft concept to implement high energy missions independent of multiplanetary swingby opportunities are assessed and recommendations offered for future work. An upper stage, solid propulsion launch vehicle augmentation system was selected as the baseline configuration in view of the established program goals of low cost and high reliability. Spacecraft and propulsion system data that characterize mission performance capabilities were generated to serve as the basis for subsequent tradeoff studies. A cost effectiveness model was used for the preliminary feasibility assessment to provide a meaningful comparative effectiveness measure of the various candidate designs. The results substantiated the feasibility of the powered spacecraft concept when used in conjunction with several intermediate-sized launch vehicles as well as the existence of energy margins by which to exploit the attainment of extended mission capabilities. Additionally, in growth option applications, the employment of advanced propulsion systems and alternate spacecraft approaches appear promising.

  11. Analysis and planning for precipitation augmentation for crops experiment. September 1990-August 1991. Annual report

    SciTech Connect

    Changnon, S.A.; Czys, R.R.; Hollinger, S.E.; Huff, F.A.; Kunkel, K.E.

    1991-11-01

    The scientific research described herein was conducted within the context of the Precipitation-Cloud Changes and Impacts Project (PreCCIP) of the Illinois State Water Survey during the period September 1, 1990 to August 31, 1991. PreCCIP is an ongoing research effort, originally entitled Precipitation Augmentation for Crops Experiment (PACE). Findings from the PreCCIP research concerning atmospheric processes and the effects of changed conditions are key inputs into a myriad of individual and institutional decisions affecting Illinois. They include major questions about (1) the application of cloud seeding to try to alter precipitation; (2) the magnitude and factors causing inadvertent climate change at the local and regional scales; (3) the types and importance of physical effects and socioeconomic impacts caused by altered weather; and (4) the monitoring, control, and regulation of activities leading to either purposeful or inadvertent modification of weather and climate.

  12. Balloon-augmented Onyx endovascular ligation: initial human experience and comparison with coil ligation.

    PubMed

    Osanai, Toshiya; Bain, Mark D; Toth, Gabor; Hussain, M Shazam; Hui, Ferdinand K

    2015-08-01

    Carotid artery sacrifice remains an important procedure for cerebral vascular disorders despite the development of new endovascular devices. Conventional carotid artery sacrifice with detachable coils alone often requires numerous coils to complete occlusion. To describe the initial human experience with balloon-augmented Onyx and coil vessel sacrifice based on our previous experience with animals. We performed a retrospective review of patients who underwent carotid artery sacrifice between 2008 and 2012 in accordance with local investigational review board approval. Two methods were used to occlude carotid arteries-namely, combined Onyx and coil embolization and traditional coil embolization. We compared the two methods for the cost of embolizate, time to occlude the vessels, and the number of coils. Eight consecutive patients (combined group n=3, traditional group n=5) were assessed. The median cost of embolic material was $6321 in the combined Onyx and coil embolization group and $29 996 in the traditional coil embolization group. The median time from first coil placement to achievement of vessel occlusion was 52 min in the Onyx group and 113 min in the coil embolization group. The median number of coils used was 4 in the Onyx group and 35 in the coil embolization group (p<0.05). No symptomatic complications or recurrences were seen in the combined group. Balloon-augmented Onyx endovascular ligation may reduce costs and fluoroscopy times during vessel sacrifice. Further studies in a larger number of patients are needed to confirm these findings. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  13. Augmenting NMDA receptor signaling boosts experience-dependent neuroplasticity in the adult human brain.

    PubMed

    Forsyth, Jennifer K; Bachman, Peter; Mathalon, Daniel H; Roach, Brian J; Asarnow, Robert F

    2015-12-15

    Experience-dependent plasticity is a fundamental property of the brain. It is critical for everyday function, is impaired in a range of neurological and psychiatric disorders, and frequently depends on long-term potentiation (LTP). Preclinical studies suggest that augmenting N-methyl-d-aspartate receptor (NMDAR) signaling may promote experience-dependent plasticity; however, a lack of noninvasive methods has limited our ability to test this idea in humans until recently. We examined the effects of enhancing NMDAR signaling using d-cycloserine (DCS) on a recently developed LTP EEG paradigm that uses high-frequency visual stimulation (HFvS) to induce neural potentiation in visual cortex neurons, as well as on three cognitive tasks: a weather prediction task (WPT), an information integration task (IIT), and a n-back task. The WPT and IIT are learning tasks that require practice with feedback to reach optimal performance. The n-back assesses working memory. Healthy adults were randomized to receive DCS (100 mg; n = 32) or placebo (n = 33); groups were similar in IQ and demographic characteristics. Participants who received DCS showed enhanced potentiation of neural responses following repetitive HFvS, as well as enhanced performance on the WPT and IIT. Groups did not differ on the n-back. Augmenting NMDAR signaling using DCS therefore enhanced activity-dependent plasticity in human adults, as demonstrated by lasting enhancement of neural potentiation following repetitive HFvS and accelerated acquisition of two learning tasks. Results highlight the utility of considering cellular mechanisms underlying distinct cognitive functions when investigating potential cognitive enhancers.

  14. Transforming Experience: The Potential of Augmented Reality and Virtual Reality for Enhancing Personal and Clinical Change

    PubMed Central

    Riva, Giuseppe; Baños, Rosa M.; Botella, Cristina; Mantovani, Fabrizia; Gaggioli, Andrea

    2016-01-01

    During life, many personal changes occur. These include changing house, school, work, and even friends and partners. However, the daily experience shows clearly that, in some situations, subjects are unable to change even if they want to. The recent advances in psychology and neuroscience are now providing a better view of personal change, the change affecting our assumptive world: (a) the focus of personal change is reducing the distance between self and reality (conflict); (b) this reduction is achieved through (1) an intense focus on the particular experience creating the conflict or (2) an internal or external reorganization of this experience; (c) personal change requires a progression through a series of different stages that however happen in discontinuous and non-linear ways; and (d) clinical psychology is often used to facilitate personal change when subjects are unable to move forward. Starting from these premises, the aim of this paper is to review the potential of virtuality for enhancing the processes of personal and clinical change. First, the paper focuses on the two leading virtual technologies – augmented reality (AR) and virtual reality (VR) – exploring their current uses in behavioral health and the outcomes of the 28 available systematic reviews and meta-analyses. Then the paper discusses the added value provided by VR and AR in transforming our external experience by focusing on the high level of personal efficacy and self-reflectiveness generated by their sense of presence and emotional engagement. Finally, it outlines the potential future use of virtuality for transforming our inner experience by structuring, altering, and/or replacing our bodily self-consciousness. The final outcome may be a new generation of transformative experiences that provide knowledge that is epistemically inaccessible to the individual until he or she has that experience, while at the same time transforming the individual’s worldview. PMID:27746747

  15. Transforming Experience: The Potential of Augmented Reality and Virtual Reality for Enhancing Personal and Clinical Change.

    PubMed

    Riva, Giuseppe; Baños, Rosa M; Botella, Cristina; Mantovani, Fabrizia; Gaggioli, Andrea

    2016-01-01

    During life, many personal changes occur. These include changing house, school, work, and even friends and partners. However, the daily experience shows clearly that, in some situations, subjects are unable to change even if they want to. The recent advances in psychology and neuroscience are now providing a better view of personal change, the change affecting our assumptive world: (a) the focus of personal change is reducing the distance between self and reality (conflict); (b) this reduction is achieved through (1) an intense focus on the particular experience creating the conflict or (2) an internal or external reorganization of this experience; (c) personal change requires a progression through a series of different stages that however happen in discontinuous and non-linear ways; and (d) clinical psychology is often used to facilitate personal change when subjects are unable to move forward. Starting from these premises, the aim of this paper is to review the potential of virtuality for enhancing the processes of personal and clinical change. First, the paper focuses on the two leading virtual technologies - augmented reality (AR) and virtual reality (VR) - exploring their current uses in behavioral health and the outcomes of the 28 available systematic reviews and meta-analyses. Then the paper discusses the added value provided by VR and AR in transforming our external experience by focusing on the high level of personal efficacy and self-reflectiveness generated by their sense of presence and emotional engagement. Finally, it outlines the potential future use of virtuality for transforming our inner experience by structuring, altering, and/or replacing our bodily self-consciousness. The final outcome may be a new generation of transformative experiences that provide knowledge that is epistemically inaccessible to the individual until he or she has that experience, while at the same time transforming the individual's worldview.

  16. Experiences of non-progressive and augmented labour among nulliparous women: a qualitative interview study in a Grounded Theory approach

    PubMed Central

    Kjaergaard, Hanne; Foldgast, Anne Maria; Dykes, Anna-Karin

    2007-01-01

    Background Non-progressive labour is the most common complication in nulliparas and is primarily treated by augmentation. Augmented labour is often terminated by instrumental delivery. Little qualitative research has addressed experiences of non-progressive and augmented deliveries. The aim of this study was to gain a deeper understanding of the experience of non-progressive and augmented labour among nulliparas and their experience of the care they received. Methods A qualitative study was conducted using individual interviews. Data was collected and analysed according to the Grounded Theory method. The participants were a purposive sample of ten women. The interviews were conducted 4–15 weeks after delivery. Results The women had contrasting experiences during the birth process. During labour there was a conflict between the expectation of having a natural delivery and actually having a medical delivery. The women experienced a feeling of separation between mind and body. Interacting with the midwife had a major influence on feelings of losing and regaining control. Reconciliation between the contrasting feelings during labour was achieved. The core category was named Dialectical Birth Process and comprised three categories: Balancing natural and medical delivery, Interacting, Losing and regaining control. Conclusion A dialectical process was identified in these women's experiences of non-progressive labour. The process is susceptible to interaction with the midwife; especially her support to the woman's feeling of being in control. Midwives should secure that the woman's recognition of the fact that the labour is non-progressive and augmentation is required is handled with respect for the dialectical process. Augmentation of labour should be managed as close to the course of natural labour and delivery as possible. PMID:17662152

  17. Experiences with a prevalidation methodology for designing integrated/propulsion control system architectures

    NASA Technical Reports Server (NTRS)

    Cohen, Gerald C.; Lee, Charles W.; Strickland, Michael J.; Palumbo, Daniel L.

    1989-01-01

    This paper describes a validation methodology and supporting analytical tools developed to provide system designers with a capability of selecting, in the early stages of development, candidate architectures for an integrated airframe/propulsion control system and of predicting their reliability and performance. The results of an application of this methodology to an integrated flight and propulsion control system demonstrated that firm system requirements are being established early in the system life cycle and that an early evaluation exposes missing and conflicting specifications. It is shown that fundamental improvements and refinements can be made early in the concept life cycle when the potential for increased performance is high and the cost and schedule impacts from changes are relatively low. The application of this methodology reduces technical risks associated with integrated system concepts incorporating new technologies.

  18. Integrated Aero-Propulsion CFD Methodology for the Hyper-X Flight Experiment

    NASA Technical Reports Server (NTRS)

    Cockrell, Charles E., Jr.; Engelund, Walter C.; Bittner, Robert D.; Dilley, Arthur D.; Jentink, Tom N.; Frendi, Abdelkader

    2000-01-01

    Computational fluid dynamics (CFD) tools have been used extensively in the analysis and development of the X-43A Hyper-X Research Vehicle (HXRV). A significant element of this analysis is the prediction of integrated vehicle aero-propulsive performance, which includes an integration of aerodynamic and propulsion flow fields. This paper describes analysis tools used and the methodology for obtaining pre-flight predictions of longitudinal performance increments. The use of higher-fidelity methods to examine flow-field characteristics and scramjet flowpath component performance is also discussed. Limited comparisons with available ground test data are shown to illustrate the approach used to calibrate methods and assess solution accuracy. Inviscid calculations to evaluate lateral-directional stability characteristics are discussed. The methodology behind 3D tip-to-tail calculations is described and the impact of 3D exhaust plume expansion in the afterbody region is illustrated. Finally, future technology development needs in the area of hypersonic propulsion-airframe integration analysis are discussed.

  19. Minority University System Engineering: A Small Satellite Design Experience Held at the Jet Propulsion Laboratory During the Summer of 1996

    NASA Technical Reports Server (NTRS)

    Ordaz, Miguel Angel

    1997-01-01

    The University of Texas at El Paso (UTEP) in conjunction with the Jet Propulsion Laboratory (JPL), North Carolina A&T and California State University of Los Angeles participated during the summer of 1996 in a prototype program known as Minority University Systems Engineering (MUSE). The program consisted of a ten week internship at JPL for students and professors of the three universities. The purpose of MUSE as set forth in the MUSE program review August 5, 1996 was for the participants to gain experience in the following areas: 1) Gain experience in a multi-disciplinary project; 2) Gain experience working in a culturally diverse atmosphere; 3) Provide field experience for students to reinforce book learning; and 4) Streamline the design process in two areas: make it more financially feasible; and make it faster.

  20. Augmenting the thermal flux experiment: A mixed reality approach with the HoloLens

    NASA Astrophysics Data System (ADS)

    Strzys, M. P.; Kapp, S.; Thees, M.; Kuhn, J.; Lukowicz, P.; Knierim, P.; Schmidt, A.

    2017-09-01

    In the field of Virtual Reality (VR) and Augmented Reality (AR), technologies have made huge progress during the last years and also reached the field of education. The virtuality continuum, ranging from pure virtuality on one side to the real world on the other, has been successfully covered by the use of immersive technologies like head-mounted displays, which allow one to embed virtual objects into the real surroundings, leading to a Mixed Reality (MR) experience. In such an environment, digital and real objects do not only coexist, but moreover are also able to interact with each other in real time. These concepts can be used to merge human perception of reality with digitally visualized sensor data, thereby making the invisible visible. As a first example, in this paper we introduce alongside the basic idea of this column an MR experiment in thermodynamics for a laboratory course for freshman students in physics or other science and engineering subjects that uses physical data from mobile devices for analyzing and displaying physical phenomena to students.

  1. Compression curves of transition metals in the Mbar range: Experiments and projector augmented-wave calculations

    NASA Astrophysics Data System (ADS)

    Dewaele, Agnès; Torrent, Marc; Loubeyre, Paul; Mezouar, Mohamed

    2008-09-01

    The ambient temperature equations of state (EoS) of iron, cobalt, nickel, zinc, molybdenum, and silver have been measured by x-ray diffraction. These transition metals were compressed using diamond anvil cells with a helium pressure transmitting medium. The maximum pressure reached during these experiments varied between 65 GPa (for cobalt) and 200 GPa (for iron). This work completes previous measurements on six other metals [Phys. Rev. B 70, 094112 (2004)] to quantify the differences between ab initio calculations and experiment on a large experimental set of transition metals. The compression curves of iron, cobalt, nickel, zinc, molybdenum, silver, platinum, and gold are also calculated ab initio within the density-functional theory (DFT) formalism using the projector augmented-wave (PAW) method and different exchange-correlation functionals (LDA, GGA-PBE, GGA-PBEsol). The difference between PAW and available all-electron calculations is found to be negligible up to very high pressures. The success of each exchange-correlation functional is correlated with the atomic number. For all metals, the bulk modulus becomes overestimated at high pressure. In addition, this extended data set of metals’ EoS enables to reduce further, but marginally, the systematic uncertainty of the high-pressure metrology based on the ruby standard.

  2. A Mixed Methods Assessment of Students' Flow Experiences during a Mobile Augmented Reality Science Game

    ERIC Educational Resources Information Center

    Bressler, D. M.; Bodzin, A. M.

    2013-01-01

    Current studies have reported that secondary students are highly engaged while playing mobile augmented reality (AR) learning games. Some researchers have posited that players' engagement may indicate a flow experience, but no research results have confirmed this hypothesis with vision-based AR learning games. This study investigated factors…

  3. A Mixed Methods Assessment of Students' Flow Experiences during a Mobile Augmented Reality Science Game

    ERIC Educational Resources Information Center

    Bressler, D. M.; Bodzin, A. M.

    2013-01-01

    Current studies have reported that secondary students are highly engaged while playing mobile augmented reality (AR) learning games. Some researchers have posited that players' engagement may indicate a flow experience, but no research results have confirmed this hypothesis with vision-based AR learning games. This study investigated factors…

  4. A Mobile Service Oriented Multiple Object Tracking Augmented Reality Architecture for Education and Learning Experiences

    ERIC Educational Resources Information Center

    Rattanarungrot, Sasithorn; White, Martin; Newbury, Paul

    2014-01-01

    This paper describes the design of our service-oriented architecture to support mobile multiple object tracking augmented reality applications applied to education and learning scenarios. The architecture is composed of a mobile multiple object tracking augmented reality client, a web service framework, and dynamic content providers. Tracking of…

  5. Initial experiences using a new implant based distraction system for alveolar ridge augmentation.

    PubMed

    Klein, C; Papageorge, M; Kovács, A; Carchidi, J E

    2001-04-01

    With this case report we demonstrate a new technique useful in augmenting alveolar ridges after resection procedures or atrophic loss of volume. The augmentation is done by means of a new osteogenic distractor (manufactured by ACE Surgical Supply Co., Inc., Brockton, MA, USA), the distraction procedure is according to Ilizarov's principles.

  6. The Electric Propulsion Space Experiment (ESEX)-A demonstration of high power arcjets for orbit transfer applications

    NASA Astrophysics Data System (ADS)

    Bromaghim, D. R.; Salasovich, R. M.; Leduc, J. R.; Johnson, L. K.

    1998-01-01

    The Electric Propulsion Space Experiment (ESEX) is a high power (30 kW) ammonia arcjet space demonstration sponsored by the Propulsion Directorate of the Phillips Laboratory with TRW as the prime contractor. ESEX is one of nine experiments being launched in early 1998 on board the Advanced Research and Global Observation Satellite (ARGOS). ESEX will demonstrate the feasibility of using a high power arcjet for orbit transfer. ESEX is instrumented with various sensors to address all of the expected interactions with ARGOS including electromagnetic interference, contamination, and radiated thermal loading. The performance of the arcjet will also be measured using ground tracking, an on-board GPS receiver, and on-board accelerometer. In addition to the performance and spacecraft interaction studies, ground-based spectroscopic and radiometric measurements will be performed to observe plume species as well as determine the effect of the arcjet firing on the space environment. ESEX is currently undergoing integrated testing with the spacecraft bus and the eight other experiments to verify the full operability of ARGOS while on-orbit. These tests include basic functionality of the system in addition to the normal suite of environmental tests including electromagnetic interference and compatibility, acoustic and pyroshock testing, and thermal vacuum tests.

  7. Adaptive Augmenting Control Flight Characterization Experiment on an F/A-18

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen S.; Gilligan, Eric T.; Wall, John H.; Orr, Jeb S.; Miller, Christopher J.; Hanson, Curtis E.

    2014-01-01

    The NASA Marshall Space Flight Center (MSFC) Flight Mechanics and Analysis Division developed an Adaptive Augmenting Control (AAC) algorithm for launch vehicles that improves robustness and performance by adapting an otherwise welltuned classical control algorithm to unexpected environments or variations in vehicle dynamics. This AAC algorithm is currently part of the baseline design for the SLS Flight Control System (FCS), but prior to this series of research flights it was the only component of the autopilot design that had not been flight tested. The Space Launch System (SLS) flight software prototype, including the adaptive component, was recently tested on a piloted aircraft at Dryden Flight Research Center (DFRC) which has the capability to achieve a high level of dynamic similarity to a launch vehicle. Scenarios for the flight test campaign were designed specifically to evaluate the AAC algorithm to ensure that it is able to achieve the expected performance improvements with no adverse impacts in nominal or nearnominal scenarios. Having completed the recent series of flight characterization experiments on DFRC's F/A-18, the AAC algorithm's capability, robustness, and reproducibility, have been successfully demonstrated. Thus, the entire SLS control architecture has been successfully flight tested in a relevant environment. This has increased NASA's confidence that the autopilot design is ready to fly on the SLS Block I vehicle and will exceed the performance of previous architectures.

  8. Large-Scale Mini-Magnetosphere Plasma Propulsion (M2P2) Experiments

    NASA Technical Reports Server (NTRS)

    Winglee, R. M.; Slough, J.; Ziemba, T.; Euripides, P.; Adrian, M. L.; Gallagher, D.; Craven, P.; Tomlinson, W.; Cravens, J.; Burch, J.; hide

    2001-01-01

    Mini-Magnetosphere Plasma Propulsion (M2P2) is an innovative plasma propulsion system that has the potential to propel spacecraft at unprecedented speeds of 50 to 80 km per second with a low-power requirement of approx. 1 kW per 100 kg of payload and approx. 1 kg of neutral gas [fuel] consumption per day of acceleration. Acceleration periods from several days to a few months are envisioned. High specific impulse and efficiency are achieved through coupling of the spacecraft to the 400 km per second solar wind through an artificial magnetosphere. The mini-magnetosphere or inflated magnetic bubble is produced by the injection of cold dense plasma into a spacecraft-generated magnetic field envelope. Magnetic bubble inflation is driven by electromagnetic processes thereby avoiding the material and deployment problems faced by mechanical solar sail designs, Here, we present the theoretical design of M2P2 as well as initial results from experimental testing of an M2P2 prototype demonstrating: 1) inflation of the dipole magnetic field geometry through the internal injection of cold plasma; and 2) deflection of and artificial solar wind by the prototype M2P2 system. In addition, we present plans for direct laboratory measurement of thrust imparted to a prototype M2P2 by an artificial solar wind during the summer of 2001.

  9. Large-Scale Mini-Magnetosphere Plasma Propulsion (M2P2) Experiments

    NASA Technical Reports Server (NTRS)

    Winglee, R. M.; Slough, J.; Ziemba, T.; Euripides, P.; Gallagher, D.; Craven, P.; Adrian, M. L.; Tomlinson, W.; Cravens, J.; Burch, J.; hide

    2001-01-01

    Mini-Magnetosphere Plasma Propulsion (M2P2) is an innovative plasma propulsion system that has the potential to propel spacecraft at unprecedented speeds of 50 to 80 km/s, with a low power requirement of approx. 1 kW per 100 kg of payload and -1 kg of neutral gas [fuel] consumption per day of acceleration. Acceleration periods from several days to a few months are envisioned. High specific impulse and efficiency are achieved through coupling of the spacecraft to the 400 km/s. solar wind through an artificial magnetosphere. The mini-magnetosphere or inflated magnetic bubble is produced by the injection of cold dense plasma into a spacecraft-generated magnetic field envelope. Magnetic bubble inflation is driven by electromagnetic processes thereby avoiding the material and deployment problems faced by mechanical solar sail designs. Here, we present the theoretical design of M2P2 as well as initial results from experimental testing of an M2P2 prototype demonstrating: 1) inflation of the dipole magnetic field geometry through the internal injection of cold plasma; and 2) deflection of and artificial solar wind by the prototype M2P2 system. In addition, we present plans for direct laboratory measurement of thrust imparted to a prototype M2P2 by an artificial solar wind during the summer of 2001.

  10. Large-Scale Mini-Magnetosphere Plasma Propulsion (M2P2) Experiments

    NASA Technical Reports Server (NTRS)

    Winglee, R. M.; Slough, J.; Ziemba, T.; Euripides, P.; Adrian, M. L.; Gallagher, D.; Craven, P.; Tomlinson, W.; Cravens, J.; Burch, J.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    Mini-Magnetosphere Plasma Propulsion (M2P2) is an innovative plasma propulsion system that has the potential to propel spacecraft at unprecedented speeds of 50 to 80 km per second with a low-power requirement of approx. 1 kW per 100 kg of payload and approx. 1 kg of neutral gas [fuel] consumption per day of acceleration. Acceleration periods from several days to a few months are envisioned. High specific impulse and efficiency are achieved through coupling of the spacecraft to the 400 km per second solar wind through an artificial magnetosphere. The mini-magnetosphere or inflated magnetic bubble is produced by the injection of cold dense plasma into a spacecraft-generated magnetic field envelope. Magnetic bubble inflation is driven by electromagnetic processes thereby avoiding the material and deployment problems faced by mechanical solar sail designs, Here, we present the theoretical design of M2P2 as well as initial results from experimental testing of an M2P2 prototype demonstrating: 1) inflation of the dipole magnetic field geometry through the internal injection of cold plasma; and 2) deflection of and artificial solar wind by the prototype M2P2 system. In addition, we present plans for direct laboratory measurement of thrust imparted to a prototype M2P2 by an artificial solar wind during the summer of 2001.

  11. Large-Scale Mini-Magnetosphere Plasma Propulsion (M2P2) Experiments

    NASA Technical Reports Server (NTRS)

    Winglee, R. M.; Slough, J.; Ziemba, T.; Euripides, P.; Gallagher, D.; Craven, P.; Adrian, M. L.; Tomlinson, W.; Cravens, J.; Burch, J.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    Mini-Magnetosphere Plasma Propulsion (M2P2) is an innovative plasma propulsion system that has the potential to propel spacecraft at unprecedented speeds of 50 to 80 km/s, with a low power requirement of approx. 1 kW per 100 kg of payload and -1 kg of neutral gas [fuel] consumption per day of acceleration. Acceleration periods from several days to a few months are envisioned. High specific impulse and efficiency are achieved through coupling of the spacecraft to the 400 km/s. solar wind through an artificial magnetosphere. The mini-magnetosphere or inflated magnetic bubble is produced by the injection of cold dense plasma into a spacecraft-generated magnetic field envelope. Magnetic bubble inflation is driven by electromagnetic processes thereby avoiding the material and deployment problems faced by mechanical solar sail designs. Here, we present the theoretical design of M2P2 as well as initial results from experimental testing of an M2P2 prototype demonstrating: 1) inflation of the dipole magnetic field geometry through the internal injection of cold plasma; and 2) deflection of and artificial solar wind by the prototype M2P2 system. In addition, we present plans for direct laboratory measurement of thrust imparted to a prototype M2P2 by an artificial solar wind during the summer of 2001.

  12. Possible applications of the LEAP motion controller for more interactive simulated experiments in augmented or virtual reality

    NASA Astrophysics Data System (ADS)

    Wozniak, Peter; Vauderwange, Oliver; Mandal, Avikarsha; Javahiraly, Nicolas; Curticapean, Dan

    2016-09-01

    Practical exercises are a crucial part of many curricula. Even simple exercises can improve the understanding of the underlying subject. Most experimental setups require special hardware. To carry out e. g. a lens experiments the students need access to an optical bench, various lenses, light sources, apertures and a screen. In our previous publication we demonstrated the use of augmented reality visualization techniques in order to let the students prepare with a simulated experimental setup. Within the context of our intended blended learning concept we want to utilize augmented or virtual reality techniques for stationary laboratory exercises. Unlike applications running on mobile devices, stationary setups can be extended more easily with additional interfaces and thus allow for more complex interactions and simulations in virtual reality (VR) and augmented reality (AR). The most significant difference is the possibility to allow interactions beyond touching a screen. The LEAP Motion controller is a small inexpensive device that allows for the tracking of the user's hands and fingers in three dimensions. It is conceivable to allow the user to interact with the simulation's virtual elements by the user's very hand position, movement and gesture. In this paper we evaluate possible applications of the LEAP Motion controller for simulated experiments in augmented and virtual reality. We pay particular attention to the devices strengths and weaknesses and want to point out useful and less useful application scenarios.

  13. Experimental investigation of a unique airbreathing pulsed laser propulsion concept

    NASA Technical Reports Server (NTRS)

    Myrabo, L. N.; Nagamatsu, H. T.; Manka, C.; Lyons, P. W.; Jones, R. A.

    1991-01-01

    Investigations were conducted into unique methods of converting pulsed laser energy into propulsive thrust across a flat impulse surface under atmospheric conditions. The propulsion experiments were performed with a 1-micron neodymium-glass laser at the Space Plasma Branch of the Naval Research Laboratory. Laser-induced impulse was measured dynamically by ballistic pendulums and statically using piezoelectric pressure transducers on a stationary impulse surface. The principal goal was to explore methods for increasing the impulse coupling performance of airbreathing laser-propulsion engines. A magnetohydrodynamic thrust augmentation effect was discovered when a tesla-level magnetic field was applied perpendicular to the impulse surface. The impulse coupling coefficient performance doubled and continued to improve with increasing laser-pulse energies. The resultant performance of 180 to 200 N-s/MJ was found to be comparable to that of the earliest afterburning turbojets.

  14. Experimental investigation of a unique airbreathing pulsed laser propulsion concept

    NASA Technical Reports Server (NTRS)

    Myrabo, L. N.; Nagamatsu, H. T.; Manka, C.; Lyons, P. W.; Jones, R. A.

    1991-01-01

    Investigations were conducted into unique methods of converting pulsed laser energy into propulsive thrust across a flat impulse surface under atmospheric conditions. The propulsion experiments were performed with a 1-micron neodymium-glass laser at the Space Plasma Branch of the Naval Research Laboratory. Laser-induced impulse was measured dynamically by ballistic pendulums and statically using piezoelectric pressure transducers on a stationary impulse surface. The principal goal was to explore methods for increasing the impulse coupling performance of airbreathing laser-propulsion engines. A magnetohydrodynamic thrust augmentation effect was discovered when a tesla-level magnetic field was applied perpendicular to the impulse surface. The impulse coupling coefficient performance doubled and continued to improve with increasing laser-pulse energies. The resultant performance of 180 to 200 N-s/MJ was found to be comparable to that of the earliest afterburning turbojets.

  15. ESA Spacecraft Propulsion Activities

    NASA Astrophysics Data System (ADS)

    Saccoccia, G.

    2004-10-01

    ESA is currently involved in several activities related to spacecraft chemical and electric propulsion, from the basic research and development of conventional and new concepts to the manufacturing, AIV and flight control of the propulsion subsystems of several European satellites. In the commercial application field, the strong competition among satellite manufacturers is a major driver for advancements in the area of propulsion, where increasing better performance together with low prices are required. Furthermore, new scientific and Earth observation missions dictate new challenging requirements for propulsion systems and components based on advanced technologies. For all these reasons, the technology area of spacecraft propulsion is in strong evolution and this paper presents an overview of the current European programmes and initiatives in this technology field. Specific attention is devoted in the paper to the performance and flight experience of spacecraft currently in orbit or ready to be launched.

  16. Laser Propulsion - Quo Vadis

    SciTech Connect

    Bohn, Willy L.

    2008-04-28

    First, an introductory overview of the different types of laser propulsion techniques will be given and illustrated by some historical examples. Second, laser devices available for basic experiments will be reviewed ranging from low power lasers sources to inertial confinement laser facilities. Subsequently, a status of work will show the impasse in which the laser propulsion community is currently engaged. Revisiting the basic relations leads to new avenues in ablative and direct laser propulsion for ground based and space based applications. Hereby, special attention will be devoted to the impact of emerging ultra-short pulse lasers on the coupling coefficient and specific impulse. In particular, laser sources and laser propulsion techniques will be tested in microgravity environment. A novel approach to debris removal will be discussed with respect to the Satellite Laser Ranging (SRL) facilities. Finally, some non technical issues will be raised aimed at the future prospects of laser propulsion in the international community.

  17. Development of the electrical power subsystem for the electric propulsion experiment onboard the Space Flyer Unit (SFU)

    SciTech Connect

    Kunii, Y.; Moriai, T.; Sasaki, H.; Okamura, T.; Harada, H.

    1987-05-01

    Bread Board Model of a few kW class electrical power subsystem is being developed for the Electric Propulsion Experiment (EPEX), which is a space experiment program for a quasi-steady MPD thruster system. EPEX is planned to be tested on a Japanese free flying platform, which is planned to be operational in the 1990s. A one-million-cycle endurance test was carried out from December 1985 to January 1986 with a 1-kW-class pulse forming network (PFN) using improved plastic film capacitors of reduced weight. The test was accomplished in a vacuum chamber with arc discharges. The BBM PFN was designed and manufactured with the results of the one-million-cycle endurance test, and a ten-million cycle endurance test is planned starting October 1987. 8 references.

  18. Propagation of sediment pulses in flume experiments simulating gravel augmentation in armored channels downstream of dams

    NASA Astrophysics Data System (ADS)

    Fadde, J.; Venditti, J. G.; Sklar, L. S.; Wydzga, A.; Nelson, P. A.; Dietrich, W. E.

    2005-12-01

    Gravel augmentation is an increasingly common river restoration strategy for armored channels downstream of dams, however, few analytical tools are available to assist river managers in selecting the appropriate sediment volumes, grain sizes, and frequency of additions to achieve desired geomorphic and ecological outcomes. Coarse sediment additions are often intended to improve habitat for spawning salmonids by altering stream bed grain size distributions, and increasing the frequency of bed mobilization and the diversity of channel morphology. Here we report preliminary results of an ongoing laboratory investigation in which we simulate the gravel augmentation process and document the spatial and temporal evolution of the bed in response to pulses of elevated fine gravel supply. The experiments are conducted in a 30-m long, 0.86-m wide flume, with a calibrated sediment feed and a tipping bucket type sediment trap that provides a continuous record of sediment flux at the downstream end of the flume. We created an initial armored bed by first achieving an active transport equilibrium slope and then shutting off the sediment feed and allowing the bed to coarsen and degrade until the transport rate became negligible. We then introduced gravel pulses of various volumes and grain sizes, and mapped the propagation of the wave of added sediment as it moved through the flume. The sediments comprising each pulse are painted distinct colors to aid in mapping and to quantify the extent of exchange with the armored bed. Mapping techniques include planform maps of zones of active transport and temporal contours of width-averaged concentrations of added gravel. We also documented the changes in bed grain size distribution using manual pebble counts before and after each run and analysis of high resolution photographs of the bed taken during the run. We also collected frequent bedload samples at regular locations along the flume length to document the movement of the gravel pulse

  19. Development of Propulsion System for Microsatellite Based on Effective COTS, and Its Demonstration in S-310-36 Sounding Rocket Experiment

    NASA Astrophysics Data System (ADS)

    Sahara, Hironori; Nakasuka, Shinichi

    The University of Tokyo, Kobe University and Vienna University of Technology conducted a set of experiments including large membrane “Furoshiki Satellite” extension and active phased array antenna operation in January 2006, by using ISAS/JAXA sounding rocket S-310-36, one of their purposes was to demonstrate a cold gasjet propulsion system for microsatellites which makes use of effective COTS. A series of verification tests concerning the propulsion were conducted on ground before the launch, and it resulted in confirmation of 70 seconds of specific impulse at 250mN of thrust with little leakage for 4 months and good resistance to vibration and shock environment of the launcher. Although specific impulse of the propulsion in orbit was not determined, the propulsion system worked very well and we acquired pressure history of its tank, and established the basis of moderate-priced propulsion system for microsatellites and are ready to salute the coming era of microsatellites equipped with propulsion.

  20. Laser space propulsion overview

    NASA Astrophysics Data System (ADS)

    Phipps, Claude; Luke, James; Helgeson, Wesley

    2007-03-01

    In this paper, we review the history of laser space propulsion from its earliest theoretical conceptions to modern practical applicatons. Applications begin with the "Lightcraft" flights of Myrabo and include practical thrusters for satellites now completing development as well as proposals for space debris removal and direct launch of payloads into orbit. We consider laser space propulsion in the most general sense, in which laser radiation is used to propel a vehicle in space. In this sense, the topic includes early proposals for pure photon propulsion, laser ablation propulsion, as well as propulsion using lasers to detonate a gas, expel a liquid, heat and expel a gas, or even to propagate power to a remote conventional electric thruster. We also discuss the most recent advances in LSP. For the first time, it is possible to consider space propulsion engines which exhibit thrust of one to several newtons while simultaneously delivering 3,000 seconds, or greater, specific impulse. No other engine concept can do both in a compact format. These willl use onboard, rather than remote, lasers. We will review the concept of chemically augmented electric propulsion, which can provide overall thrust efficiency greater than unity while maintaining very low mass to power ratio, high mean time to failure and broad operating range. The main advantage of LSP is exhaust velocity which can be instantaneously varied from 2km/s to 30km/s, simply by varying laser pulsewidth and focal spot size on target. The laser element will probably be a diode-pumped, fiber master-oscillator-power-amplifier (MOPA) system. Liquid fuels are necessary for volumetric efficiency and reliable performance at the multi-kW optical power levels required for multi-N thrust.

  1. Balloon-augmented Onyx embolization of cerebral arteriovenous malformations using a dual-lumen balloon: a multicenter experience.

    PubMed

    Spiotta, Alejandro M; James, Robert F; Lowe, Stephen R; Vargas, Jan; Turk, Aquilla S; Chaudry, M Imran; Bhalla, Tarun; Janjua, Rashid M; Delaney, John J; Quintero-Wolfe, Stacey; Turner, Raymond D

    2015-10-01

    Conventional Onyx embolization of cerebral arteriovenous malformations (AVMs) requires lengthy procedure and fluoroscopy times to form an adequate 'proximal plug' which allows forward nidal penetration while preventing reflux and non-targeted embolization. We review our experience with balloon-augmented Onyx embolization of cerebral AVMs using a dual-lumen balloon catheter technique designed to minimize these challenges. Retrospectively acquired data for all balloon-augmented cerebral AVM embolizations performed between 2011 and 2014 were obtained from four tertiary care centers. For each procedure, at least one Scepter C balloon catheter was advanced into the AVM arterial pedicle of interest and Onyx embolization was performed through the inner lumen after balloon inflation via the outer lumen. Twenty patients underwent embolization with the balloon-augmented technique over 24 discreet treatment episodes. There were 37 total arterial pedicles embolized with the balloon-augmented technique, a mean of 1.9 per patient (range 1-5). The treated AVMs were heterogeneous in their location and size (mean 3.3±1.6 cm). Mean fluoroscopy time for each procedure was 48±26 min (28 min per embolized pedicle). Two Scepter C balloon catheter-related complications (8.3% of embolization sessions, 5.4% of pedicles embolized) were observed: an intraprocedural rupture of a feeding pedicle and fracture and retention of a catheter fragment. This multicenter experience represents the largest reported series of balloon-augmented Onyx embolization of cerebral AVMs. The technique appears safe and effective in the treatment of AVMs, allowing more efficient and controlled injection of Onyx with a decreased risk of reflux and decreased fluoroscopy times. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  2. Augmented Reality Guidance for the Resection of Missing Colorectal Liver Metastases: An Initial Experience.

    PubMed

    Ntourakis, Dimitrios; Memeo, Ricardo; Soler, Luc; Marescaux, Jacques; Mutter, Didier; Pessaux, Patrick

    2016-02-01

    Modern chemotherapy achieves the shrinking of colorectal cancer liver metastases (CRLM) to such extent that they may disappear from radiological imaging. Disappearing CRLM rarely represents a complete pathological remission and have an important risk of recurrence. Augmented reality (AR) consists in the fusion of real-time patient images with a computer-generated 3D virtual patient model created from pre-operative medical imaging. The aim of this prospective pilot study is to investigate the potential of AR navigation as a tool to help locate and surgically resect missing CRLM. A 3D virtual anatomical model was created from thoracoabdominal CT-scans using customary software (VR RENDER(®), IRCAD). The virtual model was superimposed to the operative field using an Exoscope (VITOM(®), Karl Storz, Tüttlingen, Germany). Virtual and real images were manually registered in real-time using a video mixer, based on external anatomical landmarks with an estimated accuracy of 5 mm. This modality was tested in three patients, with four missing CRLM that had sizes from 12 to 24 mm, undergoing laparotomy after receiving pre-operative oxaliplatin-based chemotherapy. AR display and fine registration was performed within 6 min. AR helped detect all four missing CRLM, and guided their resection. In all cases the planned security margin of 1 cm was clear and resections were confirmed to be R0 by pathology. There was no postoperative major morbidity or mortality. No local recurrence occurred in the follow-up period of 6-22 months. This initial experience suggests that AR may be a helpful navigation tool for the resection of missing CRLM.

  3. Kite propulsion

    NASA Astrophysics Data System (ADS)

    Du Pontavice, Emmanuel; Clanet, Christophe; Quéré, David

    2014-11-01

    Kite propulsion is one way to harvest wind energy. The typical force is 1 kilo Newton per square meter, which means that with kites in the range 100 to 1000 square meters, one is able to propel ships from the trawler to the tanker. Several scientific issues arise when trying to design kites of these sizes. They first need to take off and land autonomously. This leads to the use of kites with an inflatable structure that can be compact when stored but very rigid and light once in the air. For that matter, we studied the behavior of large inflatable structures under static and dynamic load. Then, the kite needs to stay in the air. However, it appears that under certain conditions, kites without active control tend to engage into large oscillations and eventually crash. Through wind tunnel experiments, we try to understand this flight behavior to find the conditions of stability.

  4. Electric propulsion

    NASA Technical Reports Server (NTRS)

    Garrison, Philip W.

    1992-01-01

    Electric propulsion (EP) is an attractive option for unmanned orbital transfer vehicles (OTV's). Vehicles with solar electric propulsion (SEP) could be used routinely to transport cargo between nodes in Earth, lunar, and Mars orbit. Electric propulsion systems are low-thrust, high-specific-impulse systems with fuel efficiencies 2 to 10 times the efficiencies of systems using chemical propellants. The payoff for this performance can be high, since a principal cost for a space transportation system is that of launching to low Earth orbit (LEO) the propellant required for operations between LEO and other nodes. Several aspects of electric propulsion, including candidate systems and the impact of using nonterrestrial materials, are discussed.

  5. Electric propulsion

    NASA Astrophysics Data System (ADS)

    Garrison, Philip W.

    Electric propulsion (EP) is an attractive option for unmanned orbital transfer vehicles (OTV's). Vehicles with solar electric propulsion (SEP) could be used routinely to transport cargo between nodes in Earth, lunar, and Mars orbit. Electric propulsion systems are low-thrust, high-specific-impulse systems with fuel efficiencies 2 to 10 times the efficiencies of systems using chemical propellants. The payoff for this performance can be high, since a principal cost for a space transportation system is that of launching to low Earth orbit (LEO) the propellant required for operations between LEO and other nodes. Several aspects of electric propulsion, including candidate systems and the impact of using nonterrestrial materials, are discussed.

  6. Airbreathing Laser Propulsion Experiments with 1 {mu}m Terawatt Pharos IIILaser: Part 2

    SciTech Connect

    Myrabo, L. N.; Lyons, P. W.; Jones, R. A.; Liu, S.; Manka, C.

    2011-11-10

    This basic research study examines the physics of airbreathing laser propulsion at the extreme flux range of 1-2x10{sup 11} W/cm{sup 2}--within the air breakdown threshold for l {mu}m radiation--using the terawatt Pharos III neodymium-glass pulsed laser. Six different experimental setups were employed using a 34 mm line focus with 66 {mu}m focal waist, positioned near the flat impulse surface. The 2nd Campaign investigated impulse generation with the laser beam focused at grazing incidence across near horizontal target surfaces, with pulse energies ranging from 55 to 186 J, and pulse-widths of 2 to 30 ns FWHM. Laser generated impulse was measured with a horizontal Plexiglas registered ballistic pendulum equipped with either a steel target insert or 0.5 Tesla permanent magnet (NEIT-40), to quantify changes in the momentum coupling coefficient (C{sub M}). Part 2 of this 2-part paper covers Campaign no. 2 results including C{sub M} performance data, and long exposure color photos of LP plasma phenomena.

  7. Airbreathing Laser Propulsion Experiments with 1 {mu}m Terawatt Pharos III Laser: Part 1

    SciTech Connect

    Myrabo, L. N.; Lyons, P. W.; Jones, R. A.; Liu, S.; Manka, C.

    2011-11-10

    This basic research study examines the physics of airbreathing laser propulsion at the extreme flux range of 1-2x10{sup 11} W/cm{sup 2}--within the air breakdown threshold for l {mu}m radiation--using the terawatt PHAROS III neodymium-glass pulsed laser. Six different experimental setups were tested using a 34 mm line focus with 66 {mu}m focal waist, positioned near the flat impulse surface. The first campaign investigated impulse generation with the beam oriented almost normal to the target surface, with energies ranging from 23 to 376 J, and pulses of 5 to 30 ns FWHM. Air breakdown/ plasma dynamics were diagnosed with GOI cameras and color photography. Laser generated impulse was quantified with both vertical pendulums and piezoelectric pressure transducers using the standard performance metric, C{sub M}--the momentum coupling coefficient. Part 1 of this 2-part paper covers Campaign no. 1 results including laser plasma diagnostics, pressure gage and vertical pendulum data.

  8. Networking towards Employment: Experiences of People Who Use Augmentative and Alternative Communication

    ERIC Educational Resources Information Center

    Carey, Allison C.; Potts, Blyden B.; Bryen, Diane Nelson; Shankar, Jui

    2004-01-01

    Despite research that has documented the powerful role of social networks for obtaining employment, only recently has this issue been explored for people with disabilities. Drawing on qualitative data gathered from 38 individuals with severe communication disabilities who use augmentative and alternative communication (AAC), this study explores…

  9. Experiences with an Augmented Human Intellect System: A Revolution in Communication.

    ERIC Educational Resources Information Center

    Bair, James H.

    The Augmented Human Intellect System (AHI) has been designed to facilitate communication among knowledge workers who may accomplish their entire job utilizing this advanced technology. The system is capable of sending information to geographically distributed users. It permits access to and modification of stored information by a number of persons…

  10. Effectiveness of Risperidone Augmentation in Obsessive-Compulsive Disorder: Experience From a Specialty Clinic in India.

    PubMed

    Hegde, Aditya; Kalyani, Bangalore G; Arumugham, Shyam Sundar; Narayanaswamy, Janardhanan C; Math, Suresh Bada; Reddy, Y C Janardhan

    2016-08-01

    Risperidone is the most widely used augmenting agent in the treatment of obsessive-compulsive disorder (OCD). However, a recent controlled study found risperidone to be no different from placebo, raising doubts about its effectiveness. In this context, we sought to examine the real-world effectiveness of risperidone from the large database of an OCD clinic in India. A total of 1314 consecutive patients who registered at the OCD clinic between 2004 and 2014 were evaluated with structured interviews and scales. Patients with OCD initiated on risperidone augmentation without concurrent cognitive behavior therapy and who were on stable and adequate doses of serotonin reuptake inhibitors for at least 12 preceding weeks were included for analysis. The primary outcome measure was all-cause discontinuation. Logistic regression was performed to identify the factors predicting improvement with risperidone augmentation. A total of 92 patients were eligible for analysis. Risperidone continued to be used in 23 patients (25%) at the time of last follow-up, and the remaining discontinued either because of ineffectiveness or intolerability. The fall in the Yale-Brown Obsessive-Compulsive Scale scores was significantly greater in patients who continued to take risperidone when compared with those who did not (41.6% vs 3.7%, t = 6.95, P < 0.001). A total of 22 patients (24%) were noted to have at least a 25% reduction on the Yale-Brown Obsessive-Compulsive Scale scores. On regression analysis, no predictors of improvement with risperidone augmentation could be identified. The study demonstrated, in a real-world setting, that risperidone may be a useful augmenting agent in a proportion of patients with partial/poor response to serotonin reuptake inhibitors.

  11. All Seasons Vertical Augmentation Mastopexy: A Simple Algorithm, Clinical Experience, and Patient-reported Outcomes

    PubMed Central

    2016-01-01

    Background: The safety of augmentation mastopexy has been questioned. Staging has been recommended for women deemed to be at higher risk, such as women with greater degrees of ptosis. Most existing studies evaluate women treated with multiple methods, including the traditional Wise pattern. This retrospective study specifically evaluates vertical augmentation mastopexy. A simple algorithm is introduced. Methods: From 2002 to 2016, 252 women underwent consecutive vertical augmentation mastopexies performed by the author, with no staged surgery. All patients underwent a vertical mastopexy using a medially based pedicle and intraoperative nipple siting. A subset of women treated from 2012 to 2016 were surveyed to obtain outcome data; 90 patients (inclusion rate, 90%) participated. Results: The complication rate was 32.9%, including persistent ptosis, delayed wound healing, scar deformities, and asymmetry. There were no cases of nipple loss. An increased risk of complications was detected for smokers (P < 0.01), but not for combined procedures, secondary breast augmentations, or secondary mastopexies. The revision rate was 15.5%. Persistent nipple numbness was reported by 13.3% of respondents. Eighty percent of women were self-conscious about their breast appearance before surgery; 22% of respondents were self-conscious about their breasts after surgery. Seventy percent of respondents reported an improved quality of life, 94.4% would repeat the surgery, and 95.6% would recommend it. Conclusions: A simple algorithm may be used to guide treatment in women who desire correction of ptosis and upper pole fullness. An "all seasons" vertical augmentation mastopexy is safe and widely applicable. Staging is unnecessary. PMID:28293517

  12. Facial soft tissue augmentation with Artecoll®: A review of eight years of clinical experience in 153 patients

    PubMed Central

    Solomon, Philip; Sklar, Michael; Zener, Rebecca

    2012-01-01

    OBJECTIVE: Artecoll (Canderm Pharma Inc, Canada) is a semipermanent, injectable, soft tissue filler composed of uniform polymethylmethacrylate microspheres in a bovine collagen gel, which has been used in Europe over the past decade. The authors review their experience using Artecoll as an injectable material for the correction of deep static folds of the face, improvement of nasal asymmetries following rhinoplasty, depressed acne scars and augmentation of the lip. METHOD: A retrospective chart review, subjective patient satisfaction feedback and objective findings noted by the senior author were performed over an eight-year period. A total of 153 patients were treated with Artecoll injections; 74 underwent lip augmentation, 21 underwent deep nasolabial fold augmentation, eight underwent glabellar fold augmentation, 26 were treated for minor nasal dorsal irregularities and 24 were treated for depressed acne scars. RESULTS: No early or delayed allergic responses were reported. Complications occurred most commonly with lip augmentation, in which 13.5% of patients noted significant noticeable bruising postinjection that resolved completely within one week, 51.3% had detectable implant on palpation, and 13.1% required further intervention with massage, steroid injection and/or local excision to correct for lumpiness. Sixty per cent of patients requiring further intervention responded successfully, while local excision was performed on the two patients who failed to respond after six months of massage and steroid therapy. Overall, a total of 11 patients (14.9%) had minor asymmetries or less than optimal results within the lip augmentation study group. Among other sites, the most common complaint was undercorrection of the fold or wrinkle. CONCLUSION: Based on the authors’ experience, Artecoll is a safe, viable option for long-term treatment of deep facial wrinkles, nasal asymmetry, hypoplastic or atrophic lips, and depressed acne scars, and the results have been

  13. Hyaluron Filler Containing Lidocaine on a CPM Basis for Lip Augmentation: Reports from Practical Experience.

    PubMed

    Fischer, Tanja C; Sattler, Gerhard; Gauglitz, Gerd G

    2016-06-01

    Lip augmentation with hyaluronic acid fillers is established. As monophasic polydensified hyaluronic acid products with variable density, CPM-HAL1 (Belotero Balance Lidocaine, Merz Aesthetics, Raleigh, NC) and CPM-HAL2 (Belotero Intense Lidocaine, Merz Aesthetics, Raleigh, NC) are qualified for beautification and particularly natural-looking rejuvenation, respectively. The aim of this article was to assess the handling and outcome of lip augmentation using the lidocaine-containing hyaluronic acid fillers, CPM-HAL1 and CPM-HAL2. Data were documented from patients who received lip augmentation by means of beautification and/or rejuvenation using CPM-HAL1 and/or CPM-HAL2. Observation period was 4 months, with assessment of natural outcome, evenness, distribution, fluidity, handling, malleability, tolerability, as well as patient satisfaction and pain. A total of 146 patients from 21 German centers participated. Physicians rated natural outcome and evenness as good or very good for more than 95% of patients. Distribution, fluidity, handling, and malleability were assessed for both fillers as good or very good in more than 91% of patients. At every evaluation point, more than 93% of patients were very or very much satisfied with the product. A total of 125 patients (85.6%) experienced transient injection-related side effects. Pain intensity during the procedure was mild (2.72 ± 1.72 on the 0-10 pain assessment scale) and abated markedly within 30 minutes (0.42 ± 0.57). Lip augmentation with hyaluronic acid fillers produced a long-term cosmetic result. Due to the lidocaine content, procedural pain was low and transient. Accordingly, a high degree of patient satisfaction was achieved that was maintained throughout the observation period.

  14. Hybrid Wing Body Aircraft System Noise Assessment with Propulsion Airframe Aeroacoustic Experiments

    NASA Technical Reports Server (NTRS)

    Thomas, Russell H.; Burley, Casey L.; Olson, Erik D.

    2010-01-01

    A system noise assessment of a hybrid wing body configuration was performed using NASA s best available aircraft models, engine model, and system noise assessment method. A propulsion airframe aeroacoustic effects experimental database for key noise sources and interaction effects was used to provide data directly in the noise assessment where prediction methods are inadequate. NASA engine and aircraft system models were created to define the hybrid wing body aircraft concept as a twin engine aircraft with a 7500 nautical mile mission. The engines were modeled as existing technology high bypass ratio turbofans. The baseline hybrid wing body aircraft was assessed at 22 dB cumulative below the FAA Stage 4 certification level. To determine the potential for noise reduction with relatively near term technologies, seven other configurations were assessed beginning with moving the engines two fan nozzle diameters upstream of the trailing edge and then adding technologies for reduction of the highest noise sources. Aft radiated noise was expected to be the most challenging to reduce and, therefore, the experimental database focused on jet nozzle and pylon configurations that could reduce jet noise through a combination of source reduction and shielding effectiveness. The best configuration for reduction of jet noise used state-of-the-art technology chevrons with a pylon above the engine in the crown position. This configuration resulted in jet source noise reduction, favorable azimuthal directivity, and noise source relocation upstream where it is more effectively shielded by the limited airframe surface, and additional fan noise attenuation from acoustic liner on the crown pylon internal surfaces. Vertical and elevon surfaces were also assessed to add shielding area. The elevon deflection above the trailing edge showed some small additional noise reduction whereas vertical surfaces resulted in a slight noise increase. With the effects of the configurations from the

  15. Augmented Reality in astrophysics

    NASA Astrophysics Data System (ADS)

    Vogt, Frédéric P. A.; Shingles, Luke J.

    2013-09-01

    Augmented Reality consists of merging live images with virtual layers of information. The rapid growth in the popularity of smartphones and tablets over recent years has provided a large base of potential users of Augmented Reality technology, and virtual layers of information can now be attached to a wide variety of physical objects. In this article, we explore the potential of Augmented Reality for astrophysical research with two distinct experiments: (1) Augmented Posters and (2) Augmented Articles. We demonstrate that the emerging technology of Augmented Reality can already be used and implemented without expert knowledge using currently available apps. Our experiments highlight the potential of Augmented Reality to improve the communication of scientific results in the field of astrophysics. We also present feedback gathered from the Australian astrophysics community that reveals evidence of some interest in this technology by astronomers who experimented with Augmented Posters. In addition, we discuss possible future trends for Augmented Reality applications in astrophysics, and explore the current limitations associated with the technology. This Augmented Article, the first of its kind, is designed to allow the reader to directly experiment with this technology.

  16. Adaptive Augmenting Control Flight Characterization Experiment on an F/A-18

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen S.; Orr, Jeb S.; Wall, John H.; Gilligan, Eric T.

    2014-01-01

    This paper summarizes the Adaptive Augmenting Control (AAC) flight characterization experiments performed using an F/A-18 (TN 853). AAC was designed and developed specifically for launch vehicles, and is currently part of the baseline autopilot design for NASA's Space Launch System (SLS). The scope covered here includes a brief overview of the algorithm (covered in more detail elsewhere), motivation and benefits of flight testing, top-level SLS flight test objectives, applicability of the F/A-18 as a platform for testing a launch vehicle control design, test cases designed to fully vet the AAC algorithm, flight test results, and conclusions regarding the functionality of AAC. The AAC algorithm developed at Marshall Space Flight Center is a forward loop gain multiplicative adaptive algorithm that modifies the total attitude control system gain in response to sensed model errors or undesirable parasitic mode resonances. The AAC algorithm provides the capability to improve or decrease performance by balancing attitude tracking with the mitigation of parasitic dynamics, such as control-structure interaction or servo-actuator limit cycles. In the case of the latter, if unmodeled or mismodeled parasitic dynamics are present that would otherwise result in a closed-loop instability or near instability, the adaptive controller decreases the total loop gain to reduce the interaction between these dynamics and the controller. This is in contrast to traditional adaptive control logic, which focuses on improving performance by increasing gain. The computationally simple AAC attitude control algorithm has stability properties that are reconcilable in the context of classical frequency-domain criteria (i.e., gain and phase margin). The algorithm assumes that the baseline attitude control design is well-tuned for a nominal trajectory and is designed to adapt only when necessary. Furthermore, the adaptation is attracted to the nominal design and adapts only on an as-needed basis

  17. Buttock Reshaping With Intramuscular Gluteal Augmentation in an Asian Ethnic Group: A Six-Year Experience With 130 Patients.

    PubMed

    Park, Tae Hwan; Whang, Kwi Whan

    2016-09-01

    Although the definition of what constitutes "beautiful buttocks" has been changing with time, the buttocks are generally perceived as an important element of sexual attraction and beauty in every culture. In Asian culture, "beautiful buttocks" are defined by an aggregate of the following 4 components: S-shaped curvature from the lower back to the buttocks, sufficient muscle volume, sufficient fat volume, and appropriate skin elasticity. The goal of our gluteal augmentation was therefore to restore the back curvature, provide sufficient hip volume (projection), and reposition the point of maximal gluteal projection to be higher than the pubic hair. The purpose of this study was to review the authors' 6-year (2008-2014) experience with intramuscular gluteal augmentation techniques using an oval-shaped smooth-surface silicon elastomer. After intergluteal fusiform incisions were made, we bluntly dissected the subcutaneous tissue deep down to the gluteus maximus muscle by using the xyz method introduced by Dr. Gonzalez. Most of the patients in this case series underwent additional procedures at the time of the gluteal augmentation, whereas 90% of patients underwent concomitant liposuction. The results were assessed objectively using serial photography and subjectively according to patients' assessment on a 5-score scale.The mean rating for patient satisfaction with the procedure was 4.6 of 5, whereas consensus ratings by 2 independent plastic surgeons showed a mean score of 4.2 of 5. The intramuscular gluteal augmentation technique using an oval-shaped smooth surface silicon elastomer resulted in excellent cosmetic outcomes and permitted successful reshaping of the buttocks.

  18. Electrostatic propulsion beam divergence effects on spacecraft surfaces, volume 3. [effects of ion engine experiment on subsystems of ATS 6 satellite

    NASA Technical Reports Server (NTRS)

    Kemp, R. F.; Hall, D. F.; Luedke, E. E.

    1973-01-01

    Tests were conducted to determine the effects of electrostatic propulsion beam divergence effects on spacecraft surfaces. The subjects discussed are: (1) sensitive surfaces on the ATS 6 spacecraft, (2) the cesium ion source and testing facility, (3) cesium ion effects on thermophysical properties, and (4) simulated charge-exchange ion exposure. The compatibility of the ATS 6 ion engine experiment with the engineering subsystems and other experiments aboard the ATS 6 spacecraft was analyzed.

  19. Advanced Space Propulsion

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    1996-01-01

    system with a low initial development and infrastructure cost and a high operating cost. Note however that this has resulted in a 'Catch 22' standoff between the need for large initial investment that is amortized over many launches to reduce costs, and the limited number of launches possible at today's launch costs. Some examples of missions enabled (either in cost or capability) by advanced propulsion include long-life station-keeping or micro-spacecraft applications using electric propulsion or BMDO-derived micro-thrusters, low-cost orbit raising (LEO to GEO or Lunar orbit) using electric propulsion, robotic planetary missions using aerobraking or electric propulsion, piloted Mars missions using aerobraking and/or propellant production from Martian resources, very fast (100-day round-trip) piloted Mars missions using fission or fusion propulsion, and, finally, interstellar missions using fusion, antimatter, or beamed energy. The NASA Advanced Propulsion Technology program at the Jet Propulsion Laboratory (JPL) is aimed at assessing the feasibility of a range of near-term to far term advanced propulsion technologies that have the potential to reduce costs and/or enable future space activities. The program includes cooperative modeling and research activities between JPL and various universities and industry; and directly supported independent research at universities and industry. The cooperative program consists of mission studies, research and development of ion engine technology using C60 (Buckminsterfullerene) propellant, and research and development of lithium-propellant Lorentz-force accelerator (LFA) engine technology. The university/industry-supported research includes modeling and proof-of-concept experiments in advanced, high-lsp, long-life electric propulsion, and in fusion propulsion.

  20. Propulsion controlled aircraft research

    NASA Technical Reports Server (NTRS)

    Fullerton, C. Gordon

    1993-01-01

    The NASA Dryden Flight Research Facility has been conducting flight, ground simulator, and analytical studies to investigate the use of thrust modulation on multi-engine aircraft for emergency flight control. Two general methods of engine only control have been studied; manual manipulation of the throttles by the pilot, and augmented control where a computer commands thrust levels in response to pilot attitude inputs and aircraft motion feedbacks. This latter method is referred to as the Propulsion Controlled Aircraft (PCA) System. A wide variety of aircraft have been investigated. Simulation studies have included the B720, F-15, B727, B747 and MD-11. A look at manual control has been done in actual flight on the F15, T-38, B747, Lear 25, T-39, MD-11 and PA-30 Aircraft. The only inflight trial of the augmented (PCA) concept has been on an F15, the results of which will be presented below.

  1. Optical experiments on thermophoretically augmented submicron particle deposition from 'dusty' high temperature gas flows

    NASA Technical Reports Server (NTRS)

    Rosner, Daniel E.; Kim, Sang-Soo

    1984-01-01

    A real-time laser reflectivity method and Pt ribbon targets are used to obtain experimental data on the initial deposition rate of MgO(s) particles of approximately 700 nm diameter from otherwise clean combustion products as a function of target temperature (about 950-1450 K) and mainstream gas temperature (about 1500-1600 K). These preliminary data are used to demonstrate the dominant role of thermophoresis (particle drift down a temperature gradient) and to assess the utility of recently developed theoretical methods for predicting and correlating the temperature dependence of thermophoretically augmented convective-diffusion 'dust' deposition rates from flowing hot gases.

  2. A home-based intervention using augmentative and alternative communication (AAC) techniques in rural Kenya: what are the caregivers' experiences?

    PubMed

    Gona, J K; Newton, C R; Hartley, S; Bunning, K

    2014-01-01

    Caring for a child with complex communication needs associated with a developmental condition frequently adds stress to the caregiver. Furthermore, professional assistance is scarce in low-income rural settings. For such children speech is frequently unachievable. Augmentative and alternative communication provides options for supplementing or replacing speech with other techniques. The current study aimed to examine the experiences of caregivers in Kenya before and after a home-based intervention using augmentative and alternative communication techniques with children with complex communication needs. Caregivers were interviewed pre- and post-intervention. The interviews were digitally recorded, transcribed and translated into English. Content analysis was applied through the stages of text familiarization and topic organization. Emergent themes and their sub-themes were identified and labelled. Connections between themes were established and interpretations made. The procedure was completed by a second researcher independently. Conflicting ideas were jointly discussed until consensus was achieved. Four themes emerged from the data: communication process; struggle; normality; and supernatural power. Before intervention, the caregivers acknowledged their expertise in communications with the child, while also revealing their sense of isolation, burden and pain. Normality was present as a source of comparison and also an aspirational goal. Post-intervention more positive language was used to describe the child. There was an 'opening up' of communication that recognized the child's strengths and some social support systems were re-established. The power of the supernatural was recognized before and after intervention. Caring of a child with complex communication needs presents many challenges. A home-based intervention using augmentative and alternative communication techniques appears to have been a catalyst for some positive transformations in the caregivers

  3. Augmented-reality-guided biopsy of a tumor near the skull base: the surgeon's experience

    NASA Astrophysics Data System (ADS)

    Eggers, Georg; Sudra, Gunther; Ghanai, Sassan; Salb, Tobias; Dillmann, Ruediger; Marmulla, Ruediger; Hassfeld, Stefan

    2005-04-01

    INPRES, a system for Augmented Reality has been developed in the collaborative research center "Information Technology in Medicine - Computer- and Sensor-Aided Surgery". The system is based on see-through glasses. In extensive preclinical testing the system has proven its functionality and tests with volunteers had been performed successfully, based on MRI imaging. We report the surgeons view of the first use of the system for AR guided biopsy of a tumour near the skull base. Preoperative planning was performed based on CT image data. The information to be projected was the tumour volume and was segmented from image data. With the use of infrared cameras, the positions of patient and surgeon were tracked intraoperatively and the information on the glasses displays was updated accordingly. The systems proved its functionality under OR conditions in patient care: Augmented reality information could be visualized with sufficient accuracy for the surgical task. After intraoperative calibration by the surgeon, the biopsy was acquired successfully. The advantage of see through glasses is their flexibility. A virtual stereoscopic image can be set up wherever and whenever desired. A biopsy at a delicate location could be performed without the need for wide exposure. This means additional safety and lower operation related morbidity to the patient. The integration of the calibration-procedure of the glasses into the intraoperative workflow is of importance to the surgeon.

  4. NASA Breakthrough Propulsion Physics Program

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    1998-01-01

    In 1996, NASA established the Breakthrough Propulsion Physics program to seek the ultimate breakthroughs in space transportation: propulsion that requires no propellant mass, propulsion that attains the maximum transit speeds physically possible, and breakthrough methods of energy production to power such devices. Topics of interest include experiments and theories regarding the coupling of gravity and electromagnetism, vacuum fluctuation energy, warp drives and worm-holes, and superluminal quantum effects. Because these propulsion goals are presumably far from fruition, a special emphasis is to identify affordable, near-term, and credible research that could make measurable progress toward these propulsion goals. The methods of the program and the results of the 1997 workshop are presented. This Breakthrough Propulsion Physics program, managed by Lewis Research Center, is one part of a comprehensive, long range Advanced Space Transportation Plan managed by Marshall Space Flight Center.

  5. Results from a Pre-Ionization Study of a 30 kW RMF-FRC Experiment for Space Propulsion

    NASA Astrophysics Data System (ADS)

    Hill, Carrie; Uchizono, Nolan; Holmes, Michael

    2016-10-01

    Field-Reversed-Configuration (FRC) plasma thrusters are an attractive concept for in-space propulsion. These thrusters operate in a quasi-steady manner by expelling successive bursts of FRC plasmoids on the order of the neutral-gas refill rate. Pre-ionization (PI) of the seed gas is a challenge for these repetitive systems as the starting mix is a combination of the hot remnants from the recently-departed FRC and the cold refill gas. Pre-ionization of this mixture is critical to the RMF current drive and energy coupling of the system and therefore must be optimized to maximize performance. An empirical PI study was conducted on a 30-kW RMF-FRC benchtop experiment to examine how coil geometry and initial plasma distribution affects the plasmoid formation and acceleration processes. Three different inductively-coupled PI coil geometries were investigated. Their effectiveness was monitored by recording the downstream plasma velocity distribution, density, and energy coupling to the RMF antennas. The initial seed plasma created by these sources was also mapped in limited regions to compare the starting conditions for the FRC plasmoid in each case.

  6. Working group report on beam plasmas, electronic propulsion, and active experiments using beams

    NASA Technical Reports Server (NTRS)

    Dawson, J. M.; Eastman, T.; Gabriel, S.; Hawkins, J.; Matossian, J.; Raitt, J.; Reeves, G.; Sasaki, S.; Szuszczewicz, E.; Winkler, J. R.

    1986-01-01

    The JPL Workshop addressed a number of plasma issues that bear on advanced spaceborne technology for the years 2000 and beyond. Primary interest was on the permanently manned space station with a focus on identifying environmentally related issues requiring early clarification by spaceborne plasma experimentation. The Beams Working Group focused on environmentally related threats that platform operations could have on the conduct and integrity of spaceborne beam experiments and vice versa. Considerations were to include particle beams and plumes. For purposes of definition it was agreed that the term particle beams described a directed flow of charged or neutral particles allowing single-particle trajectories to represent the characteristics of the beam and its propagation. On the other hand, the word plume was adopted to describe a multidimensional flow (or expansion) of a plasma or neutral gas cloud. Within the framework of these definitions, experiment categories included: (1) Neutral- and charged-particle beam propagation, with considerations extending to high powers and currents. (2) Evolution and dynamics of naturally occurring and man-made plasma and neutral gas clouds. In both categories, scientific interest focused on interactions with the ambient geoplasma and the evolution of particle densities, energy distribution functions, waves, and fields.

  7. Focused technology: Nuclear propulsion

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.

    1993-01-01

    Five viewgraphs are presented that outline the objectives and elements of the Nuclear Propulsion Program, mission considerations, propulsion technologies, and the logic flow path for nuclear propulsion development.

  8. An independent shopping experience for wheelchair users through augmented reality and RFID.

    PubMed

    Rashid, Zulqarnain; Pous, Rafael; Norrie, Christopher S

    2017-06-23

    People with physical and mobility impairments continue to struggle to attain independence in the performance of routine activities and tasks. For example, browsing in a store and interacting with products located beyond an arm's length may be impossible without the enabling intervention of a human assistant. This research article describes a study undertaken to design, develop, and evaluate potential interaction methods for motor-impaired individuals, specifically those who use wheelchairs. Our study includes a user-centered approach, and a categorization of wheelchair users based upon the severity of their disability and their individual needs. We designed and developed access solutions that utilize radio frequency identification (RFID), augmented reality (AR), and touchscreen technologies in order to help people who use wheelchairs to carry out certain tasks autonomously. In this way, they have been empowered to go shopping independently, free from reliance upon the assistance of others. A total of 18 wheelchair users participated in the completed study.

  9. "On the Augmented Cognition Approach to Early Warning Systems- Human System Integration NASA Experiance

    NASA Astrophysics Data System (ADS)

    Achimowicz, Jerzy; Bakowski, Rafal; Mazur, Andrzej

    2014-05-01

    The authors present results related to the implementation of augmented cognition approach to severe weather early warning systems in aviation and aerospace operational environment. The limitations of automation and adaptive approach in severe weather warning systems are discussed. Also the positive impact of HSI (Human System Integration) NASA approach will be shown, in the process of pilot training in minimal weather conditions. The flight safety procedures related to weather conditions will be analyzed and the meteorological general aviation weather support product developed at IMGW will be presented. Special emphasis will be put on the integration of the military and civilian weather radar/lighting detection systems and the impact of space weather on aerospace operations including the use of unmanned RPAS (Remotely Controlled Aircraf Systems). J.Z. Achimowicz is also affiliated with Flight Safety Division of Military Institute of Aviation Medicine, Warsaw, Poland.

  10. Laser Propulsion Standardization Issues

    SciTech Connect

    Scharring, Stefan; Eckel, Hans-Albert; Roeser, Hans-Peter; Sinko, John E.; Sasoh, Akihiro

    2010-10-08

    It is a relevant issue in the research on laser propulsion that experimental results are treated seriously and that meaningful scientific comparison is possible between groups using different equipment and measurement techniques. However, critical aspects of experimental measurements are sparsely addressed in the literature. In addition, few studies so far have the benefit of independent confirmation by other laser propulsion groups. In this paper, we recommend several approaches towards standardization of published laser propulsion experiments. Such standards are particularly important for the measurement of laser ablation pulse energy, laser spot area, imparted impulse or thrust, and mass removal during ablation. Related examples are presented from experiences of an actual scientific cooperation between NU and DLR. On the basis of a given standardization, researchers may better understand and contribute their findings more clearly in the future, and compare those findings confidently with those already published in the laser propulsion literature. Relevant ISO standards are analyzed, and revised formats are recommended for application to laser propulsion studies.

  11. Electrolysis Propulsion for Spacecraft Applications

    NASA Technical Reports Server (NTRS)

    deGroot, Wim A.; Arrington, Lynn A.; McElroy, James F.; Mitlitsky, Fred; Weisberg, Andrew H.; Carter, Preston H., II; Myers, Blake; Reed, Brian D.

    1997-01-01

    Electrolysis propulsion has been recognized over the last several decades as a viable option to meet many satellite and spacecraft propulsion requirements. This technology, however, was never used for in-space missions. In the same time frame, water based fuel cells have flown in a number of missions. These systems have many components similar to electrolysis propulsion systems. Recent advances in component technology include: lightweight tankage, water vapor feed electrolysis, fuel cell technology, and thrust chamber materials for propulsion. Taken together, these developments make propulsion and/or power using electrolysis/fuel cell technology very attractive as separate or integrated systems. A water electrolysis propulsion testbed was constructed and tested in a joint NASA/Hamilton Standard/Lawrence Livermore National Laboratories program to demonstrate these technology developments for propulsion. The results from these testbed experiments using a I-N thruster are presented. A concept to integrate a propulsion system and a fuel cell system into a unitized spacecraft propulsion and power system is outlined.

  12. Minimally Invasive Spinal Arthrodesis in Osteoporotic Population Using a Cannulated and Fenestrated Augmented Screw: Technical Description and Clinical Experience

    PubMed Central

    Lubansu, Alphonse; Rynkowski, Michal; Abeloos, Laurence; Appelboom, Geoffrey; Dewitte, Olivier

    2012-01-01

    We describe a percutaneous or minimally invasive approach to apply an augmentation of pedicle fenestrated screws by injection of the PMMA bone cement through the implant and determine the safety and efficiency of this technique in a clinical series of 15 elderly osteoporotic patients. Clinical outcome and the function were assessed using respectively the Visual Analogue Scale (VAS) score and the Oswestry Disability Index (ODI). Peri- and post-operative complications were monitored during a minimum of 2 years of follow-up. Radiographic follow-up was based on plain fluoroscopic control at 3, 6 and 12 months and every year. In this approach, four steps were considered with care: optimal positioning of the screws, correct alignment of the screw heads, waiting time before the injection of cement, fluoroscopic control of the cement injection. Using these precautions, only 2 minor complications occurred. VAS scores and ODI questionnaires showed a statistically significant improvement up to 13.3 months postoperatively. No radiological complications were observed. Based on this experience, PMMA augmentation technique through the novel fenestrated screws provided an effective and long lasting fixation in osteoporotic patients. Applying this procedure through percutaneous or minimally invasive approach under fluoroscopic control seems to be safe. PMID:22970360

  13. Transarterial coil-augmented Onyx embolization for brain arteriovenous malformation. Technique and experience in 22 consecutive patients.

    PubMed

    Gao, Xu; Liang, Guobiao; Li, Zhiqing; Wang, Xiaogang; Yu, Chunyong; Cao, Peng; Chen, Jun; Li, Jingyuan

    2014-01-01

    Onyx has been widely adopted for the treatment of arteriovenous malformations (AVMs). However, its control demands operators accumulate a considerable learning curve. We describe our initial experience using a novel injection method for the embolization of AVMs. We retrospectively reviewed the data of all 22 patients with brain AVMs (12 men, 10 women; age range, 12-68 years; mean age, 43.2 years) treated by the transarterial coil-augmented Onyx injection technique. The size of the AVMs ranged from 25 mm to 70 mm (average 35.6 mm). The technical feasibility of the procedure, procedure-related complications, angiographic results, and clinical outcome were evaluated. In every case, endovascular treatment (EVT) was completed. A total of 31 sessions were performed, with a mean injection volume of 6.1 mL (range, 1.5-16.0 mL). An average of 96.7% (range 85%-100%) estimated size reduction was achieved, and 18 AVMs could be completely excluded by EVT alone. The results remained stable on follow-up angiograms. A procedural complication occurred in one patient, with permanent mild neurologic deficit. Our preliminary series demonstrated that the coil-augmented Onyx injection technique is a valuable adjunct achieving excellent nidal penetration and improving the safety of the procedure.

  14. Towards Pervasive Augmented Reality: Context-Awareness in Augmented Reality.

    PubMed

    Grubert, Jens; Langlotz, Tobias; Zollmann, Stefanie; Regenbrecht, Holger

    2017-06-01

    Augmented Reality is a technique that enables users to interact with their physical environment through the overlay of digital information. While being researched for decades, more recently, Augmented Reality moved out of the research labs and into the field. While most of the applications are used sporadically and for one particular task only, current and future scenarios will provide a continuous and multi-purpose user experience. Therefore, in this paper, we present the concept of Pervasive Augmented Reality, aiming to provide such an experience by sensing the user's current context and adapting the AR system based on the changing requirements and constraints. We present a taxonomy for Pervasive Augmented Reality and context-aware Augmented Reality, which classifies context sources and context targets relevant for implementing such a context-aware, continuous Augmented Reality experience. We further summarize existing approaches that contribute towards Pervasive Augmented Reality. Based our taxonomy and survey, we identify challenges for future research directions in Pervasive Augmented Reality.

  15. Experiences in Sensor-Augmented Pump Therapy in Families with two Children with Type 1 diabetes: A Qualitative Study.

    PubMed

    Bomba, Franziska; Müller-Godeffroy, Esther; von Sengbusch, Simone

    2017-07-27

    Background Caring for a child with type 1 diabetes is a tremendous challenge for a family. The aim of the study was to explore the experiences of transition to sensor-augmented pump therapy (SAP) in families with 2 affected children and the internal and external conditions which potentially impede or facilitate the adjustment process. Methods 5 families (9 parents, 8 children and adolescents) who used the SAP technology for 6 months were interviewed to describe their experiences. The interviews were analysed using thematic content analysis. Results Qualitative analysis of the transcribed interviews revealed that the adaptation process to SAP consisted of several phases and differed among families. There were benefits as well as hassles of using SAP with regard to managing the diabetes, and psychosocial issues: school and peer relations, as well as family relations. While parents clearly regarded the improved metabolic control and hypoglycaemic safety as the most important benefits of SAP, the hassles reported as most important covered a wide range, from technical problems of the system to family conflicts. On the whole, families rated the experience of using SAP as a positive one, with most recommending SAP to other families as long as they were willing to come to terms with the technology and commit to the work and time involved. Conclusion Sensor-augmented pump therapy can be extremely beneficial and a resource for families who care for more than one child with diabetes. During the adaptation process there is a great need of education and frequent follow-up e. g., by telemedical support. © Georg Thieme Verlag KG Stuttgart · New York.

  16. YF-12 propulsion research program and results

    NASA Technical Reports Server (NTRS)

    Albers, J. A.; Olinger, F. V.

    1976-01-01

    The objectives and status of the propulsion program, along with the results acquired in the various technology areas, are discussed. The instrumentation requirements for and experience with flight testing the propulsion systems at high supersonic cruise are reported. Propulsion system performance differences between wind tunnel and flight are given. The effects of high frequency flow fluctuations (transients) on the stability of the propulsion system are described, and shock position control is evaluated.

  17. Vertebral Augmentation with Nitinol Endoprosthesis: Clinical Experience in 40 Patients with 1-Year Follow-up

    SciTech Connect

    Anselmetti, Giovanni Carlo; Manca, Antonio; Marcia, Stefano; Chiara, Gabriele; Marini, Stefano; Baroud, Gamal; Regge, Daniele; Montemurro, Filippo

    2013-05-08

    PurposeThis study was designed to assess the clinical outcomes of patients treated by vertebral augmentation with nitinol endoprosthesis (VNE) to treat painful vertebral compression fractures.MethodsForty patients with one or more painful osteoporotic VCF, confirmed by MRI and accompanied by back-pain unresponsive to a minimum 2 months of conservative medical treatment, underwent VNE at 42 levels. Preoperative and postoperative pain measured with Visual Analog Scale (VAS), disability measured by Oswestry Disability Index (ODI), and vertebral height restoration (measured with 2-dimensional reconstruction CT) were compared at last follow-up (average follow-up 15 months). Cement extravasation, subsequent fractures, and implant migration were recorded.ResultsLong-term follow-up was obtained in 38 of 40 patients. Both VAS and ODI significantly improved from a median of 8.0 (range 5–10) and 66 % (range 44–88 %) to 0.5 (range 0–8) and 6 % (range 6–66 %), respectively, at 1 year (p < 0.0001). Vertebral height measurements comparing time points increased in a statistically significant manner (ANOVA, p < 0.001). Overall cement extravasation rate was 9.5 %. Discal and venous leakage rates were 7.1 and 0 % respectively. No symptomatic extravasations occurred. Five of 38 (13.1 %) patients experienced new spontaneous, osteoporotic fractures. No device change or migration was observed.ConclusionsVNE is a safe and effective procedure that is able to provide long-lasting pain relief and durable vertebral height gain with a low rate of new fractures and cement leakages.

  18. Vertebral augmentation by kyphoplasty and vertebroplasty: 8 years experience outcomes and complications

    PubMed Central

    Yaltirik, Kaan; Ashour, Ahmed M; Reis, Conner R; Özdoğan, Selçuk; Atalay, Başar

    2016-01-01

    Background and Context: Minimally invasive percutaneous vertebral augmentation techniques; vertebroplasty, and kyphoplasty have been treatment choices for vertebral compression fractures (VCFs). The purpose of this study is to evaluate the outcomes of the patients who underwent vertebroplasty or kyphoplasty regarding complications, correction of vertebral body height, kyphosis angle and pain relief assessment using visual analog score (VAS) for pain. Materials and Methods: A retrospective review of the hospital records for 100 consecutive patients treated with kyphoplasty or vertebroplasty in our department database. Patients with osteoporotic compression fractures, traumatic compressions, and osteolytic vertebral lesions, including metastases, hemangiomas, and multiple myeloma, were included in the study. Preoperative and postoperative VAS pain scores, percentages of vertebral compression and kyphotic angles were measured and compared as well as demographic characteristics and postoperative complications. Mobilization and length of stay (LOS) were recorded. Results: One hundred patients were treated by 110 procedures. 64 patients were operated on due to osteoporosis (72 procedures). Twelve patients were operated on because of metastasis (13 procedures), 8 patients were operated on because of multiple myeloma (9 procedures). Five patients had two surgeries, 1 patient had 3 surgeries, and 1 patient had 5 surgeries. The mean preoperative VAS was 74.05 ± 9.8. In total, 175 levels were treated, 46 levels by kyphoplasty and 129 by vertebroplasty. The mean postoperative VAS was 20.94 ± 11.8. Most of the patients were mobilized in the same day they of surgery. Mean LOS was 1.83 days. Six patients had nonsymptomatic leakage of polymethlymethacrylate, and patient had epidural hematoma, which was operated on performing hemi-laminectomy. Conclusions: Percutaneous vertebroplasty and balloon kyphoplasty are both effective and safe minimally invasive procedures for the

  19. Short segment pedicle screw instrumentation and augmentation vertebroplasty in lumbar burst fractures: an experience

    PubMed Central

    Akbar, Saleem; Dhar, Shabir A.

    2008-01-01

    To assess the efficacy and feasibility of vertebroplasty and posterior short-segment pedicle screw fixation for the treatment of traumatic lumbar burst fractures. Short-segment pedicle screw instrumentation is a well described technique to reduce and stabilize thoracic and lumbar spine fractures. It is relatively a easy procedure but can only indirectly reduce a fractured vertebral body, and the means of augmenting the anterior column are limited. Hardware failure and a loss of reduction are recognized complications caused by insufficient anterior column support. Patients with traumatic lumbar burst fractures without neurologic deficits were included. After a short segment posterior reduction and fixation, bilateral transpedicular reduction of the endplate was performed using a balloon, and polymethyl methacrylate cement was injected. Pre-operative and post-operative central and anterior heights were assessed with radiographs and MRI. Sixteen patients underwent this procedure, and a substantial reduction of the endplates could be achieved with the technique. All patients recovered uneventfully, and the neurologic examination revealed no deficits. The post-operative radiographs and magnetic resonance images demonstrated a good fracture reduction and filling of the bone defect without unwarranted bone displacement. The central and anterior height of the vertebral body could be restored to 72 and 82% of the estimated intact height, respectively. Complications were cement leakage in three cases without clinical implications and one superficial wound infection. Posterior short-segment pedicle fixation in conjunction with balloon vertebroplasty seems to be a feasible option in the management of lumbar burst fractures, thereby addressing all the three columns through a single approach. Although cement leakage occurred but had no clinical consequences or neurological deficit. PMID:18193300

  20. Prediction methods for jet V/STOL propulsion aerodynamics

    NASA Technical Reports Server (NTRS)

    Platzer, M. F.; Margason, R. J.

    1976-01-01

    The current status of prediction methods for propulsive flows and propulsion-induced effects which occur on jet V/STOL aircraft is reviewed. Among the major topics studied are flows in propulsive ducts, propulsion-induced ground and thermal effects, aerodynamic loads induced during V/STOL and transition flight, flow vectoring devices, and thrust augmented ejector and lift-fan studies. The current predictive capability in jet V/STOL propulsion aerodynamics is assessed. Future research needs are identified, with particular reference to activities that can improve the usefulness of prediction methods for jet V/STOL aircraft.

  1. Propulsion controls

    NASA Technical Reports Server (NTRS)

    Harkney, R. D.

    1980-01-01

    Increased system requirements and functional integration with the aircraft have placed an increased demand on control system capability and reliability. To provide these at an affordable cost and weight and because of the rapid advances in electronic technology, hydromechanical systems are being phased out in favor of digital electronic systems. The transition is expected to be orderly from electronic trimming of hydromechanical controls to full authority digital electronic control. Future propulsion system controls will be highly reliable full authority digital electronic with selected component and circuit redundancy to provide the required safety and reliability. Redundancy may include a complete backup control of a different technology for single engine applications. The propulsion control will be required to communicate rapidly with the various flight and fire control avionics as part of an integrated control concept.

  2. Propulsion materials

    SciTech Connect

    Wall, Edward J.; Sullivan, Rogelio A.; Gibbs, Jerry L.

    2008-01-01

    The Department of Energy’s (DOE’s) Office of Vehicle Technologies (OVT) is pleased to introduce the FY 2007 Annual Progress Report for the Propulsion Materials Research and Development Program. Together with DOE national laboratories and in partnership with private industry and universities across the United States, the program continues to engage in research and development (R&D) that provides enabling materials technology for fuel-efficient and environmentally friendly commercial and passenger vehicles.

  3. Propulsion Systems

    DTIC Science & Technology

    2011-03-31

    6. Conduct Trade Studies Choose a baseline propulsion system Document trade results and the reasons for those results. Iterate the process as...control of electrical power (typically 1-5 kW, but modules of 30 kW have been flown [Cassidy, 2002]) is expensive. The regular obsolescence of...has long focused on MPD thrusters, which scale best for power levels above 100 kW. Metal propellants such as lithium have been proposed [ Tikhonov

  4. Timonium Elementary School Solar Energy Heating and Cooling Augmentation Experiment. Final Engineering Report. Executive Summary.

    ERIC Educational Resources Information Center

    AAI Corp., Baltimore, MD.

    This report covers a two-year and seven-month solar space heating and cooling experiment conducted at the Timonium Elementary School, Timonium, Maryland. The system was designed to provide a minimum of 50 percent of the energy required during the heating season and to determine the feasibility of using solar energy to power absorption-type…

  5. Timonium Elementary School Solar Energy Heating and Cooling Augmentation Experiment. Final Engineering Report. Executive Summary.

    ERIC Educational Resources Information Center

    AAI Corp., Baltimore, MD.

    This report covers a two-year and seven-month solar space heating and cooling experiment conducted at the Timonium Elementary School, Timonium, Maryland. The system was designed to provide a minimum of 50 percent of the energy required during the heating season and to determine the feasibility of using solar energy to power absorption-type…

  6. Solar Energy School Heating Augmentation Experiment. Design, Construction and Initial Operation. A Report.

    ERIC Educational Resources Information Center

    InterTechnology Corp., Warrenton, VA.

    This report describes an experimental solar heating system, complete with thermal storage and controls, that has met all the heating requirements of five detached classrooms of the Fauquier High School in Warrenton, Virginia. The objectives of the experiment were to (1) demonstrate that solar energy can be used to provide a substantial part of the…

  7. Social media experiences of adolescents and young adults with cerebral palsy who use augmentative and alternative communication.

    PubMed

    Caron, Jessica Gosnell; Light, Janice

    2017-02-01

    This pilot study aimed to expand the current understanding of how adolescents and young adults with cerebral palsy (CP) and complex communication needs use social media. An online focus group was used to investigate the social media experiences of seven individuals with CP who used Augmentative and Alternative Communication (AAC). Questions posed to the group related to social media: (a) advantages; (b) disadvantages; (c) barriers; (d) supports; and (e) recommendations. Adolescents with CP who use AAC used a range of communication media to participate in daily interactions, including social media. An analysis of the focus group interaction revealed that the participants used social media to: bypass the constraints of face-to-face interactions; communicate for a number of reasons (e.g. maintain relationships, share experiences); and support independent leisure (e.g. playing games, looking at pictures/videos). Despite the advantages, the participants discussed barriers including limitations related to AAC technologies, social media sites and literacy skills. The results suggest that service providers should implement interventions to support social media use, including enhancement of linguistic, operational and strategic competence. Technology manufacturers should focus on improving the designs of AAC apps and social media sites to facilitate access by individuals who require AAC.

  8. Teaching Partner-Focused Questions to Students Who Use Augmentative Communication to Initiate and Lengthen Their Communication Experiences

    ERIC Educational Resources Information Center

    Moore, Sondra; Rettig, Michael A.

    2009-01-01

    Students that use augmentative communication often have a hard time breaking into conversations, initiating conversations and then being able to sustain a conversation. Students that use augmentative communication (ACC) need training in not only the use of the machine but in social communication rules, and in strategies on how to bypass…

  9. The Propulsive-Only Flight Control Problem

    NASA Technical Reports Server (NTRS)

    Blezad, Daniel J.

    1996-01-01

    Attitude control of aircraft using only the throttles is investigated. The long time constants of both the engines and of the aircraft dynamics, together with the coupling between longitudinal and lateral aircraft modes make piloted flight with failed control surfaces hazardous, especially when attempting to land. This research documents the results of in-flight operation using simulated failed flight controls and ground simulations of piloted propulsive-only control to touchdown. Augmentation control laws to assist the pilot are described using both optimal control and classical feedback methods. Piloted simulation using augmentation shows that simple and effective augmented control can be achieved in a wide variety of failed configurations.

  10. PIRE Experience Reaches out to the Russian Far East and Augments Graduate Education Abroad

    NASA Astrophysics Data System (ADS)

    Almberg, L. D.; Eichelberger, J. C.; Izbekov, P.; Ushakov, S.; Vesna, E.

    2006-12-01

    NSF's Partners in International Research and Education (PIRE) program seeks to introduce American students to collaborative international science early in their graduate careers. The intent is that the next generation of American scientists will be better prepared to work at the international level. The emphases on partnership and learning about the culture of the host country is a welcome and productive change from the `grab and dash' approach that can characterize `Winter national' projects. Our PIRE project, US-Russia-Japan Partnership in Volcanological Research and Education, is an interdisciplinary investigation of the magma systems at Bezymianny and Shiveluch Volcanoes in Kamchatka, Russia and Mount St Helens in Washington, USA. We wish to understand how massive edifice collapse at all three volcanoes perturbed the magma systems and influenced subsequent and continuing eruptive behavior. Seven American graduate students from the universities of Alaska, Hawaii, Washington, Oregon, and Stanford embarked on a personal and professional development adventure in July and August, 2006. Their experience began in Fairbanks, AK with preparations for remote foreign field work and research planning with mentor scientists. The adventure continued in Petropavlosk-Kamchatsky, Kamchatka, which required circumnavigation of the world as no airlines fly between Anchorage and Petropavlovsk. Faculty at Kamchatka State University provided intensive short courses for two weeks, introducing students to Russian language, culture, geography and history while they adjusted to the new environment and met Russian counterparts at the Institute of Volcanology and Seismology. Afternoon discussions with Russian experts in volcanology, seismology, tectonics and tephrachronology were enlightening and influenced the research plans. Russian graduate and advanced undergraduate students joined the group at the helicopter accessed camp on Bezymianny volcano. Two young Russian scientists headed the

  11. Laser propulsion

    NASA Technical Reports Server (NTRS)

    Rom, F. E.; Putre, H. A.

    1972-01-01

    The use of an earth-based high-power laser beam to provide energy for earth-launched rocket vehicle is investigated. The laser beam energy is absorbed in an opaque propellant gas and is converted to high-specific-impulse thrust by expanding the heated propellant to space by means of a nozzle. This laser propulsion scheme can produce specific impulses of several thousand seconds. Payload to gross-weight fractions about an order of magnitude higher than those for conventional chemical earth-launched vehicles appear possible. There is a potential for a significant reduction in cost per payload mass in earth orbit.

  12. Control-Volume Analysis Of Thrust-Augmenting Ejectors

    NASA Technical Reports Server (NTRS)

    Drummond, Colin K.

    1990-01-01

    New method of analysis of transient flow in thrust-augmenting ejector based on control-volume formulation of governing equations. Considered as potential elements of propulsion subsystems of short-takeoff/vertical-landing airplanes.

  13. Augmented reality: a review.

    PubMed

    Berryman, Donna R

    2012-01-01

    Augmented reality is a technology that overlays digital information on objects or places in the real world for the purpose of enhancing the user experience. It is not virtual reality, that is, the technology that creates a totally digital or computer created environment. Augmented reality, with its ability to combine reality and digital information, is being studied and implemented in medicine, marketing, museums, fashion, and numerous other areas. This article presents an overview of augmented reality, discussing what it is, how it works, its current implementations, and its potential impact on libraries.

  14. A review of electric propulsion systems and mission applications

    NASA Technical Reports Server (NTRS)

    Vondra, R.; Nock, K.; Jones, R.

    1984-01-01

    The satisfaction of growing demands for access to space resources will require new developments related to advanced propulsion and power technologies. A key technology in this context is concerned with the utilization of electric propulsion. A brief review of the current state of development of electric propulsion systems on an international basis is provided, taking into account advances in the USSR, the U.S., Japan, West Germany, China and Brazil. The present investigation, however, is mainly concerned with the U.S. program. The three basic types of electric thrusters are considered along with the intrinsic differences between chemical and electric propulsion, the resistojet, the augmented hydrazine thruster, the arcjet, the ion auxiliary propulsion system flight test, the pulsed plasma thruster, magnetoplasmadynamic propulsion, a pulsed inductive thruster, and rail accelerators. Attention is also given to the applications of electric propulsion.

  15. A review of electric propulsion systems and mission applications

    NASA Technical Reports Server (NTRS)

    Vondra, R.; Nock, K.; Jones, R.

    1984-01-01

    The satisfaction of growing demands for access to space resources will require new developments related to advanced propulsion and power technologies. A key technology in this context is concerned with the utilization of electric propulsion. A brief review of the current state of development of electric propulsion systems on an international basis is provided, taking into account advances in the USSR, the U.S., Japan, West Germany, China and Brazil. The present investigation, however, is mainly concerned with the U.S. program. The three basic types of electric thrusters are considered along with the intrinsic differences between chemical and electric propulsion, the resistojet, the augmented hydrazine thruster, the arcjet, the ion auxiliary propulsion system flight test, the pulsed plasma thruster, magnetoplasmadynamic propulsion, a pulsed inductive thruster, and rail accelerators. Attention is also given to the applications of electric propulsion.

  16. Vortex Lift Augmentation by Suction

    NASA Technical Reports Server (NTRS)

    Taylor, A. H.; Jackson, L. R.; Huffman, J. K.

    1983-01-01

    Lift performance is improved on a 60 degrees swept Gothic wing. Vortex lift at moderate to high angles of attack on highly swept wings used to improve takeoff performance and maneuverability. New design proposed in which suction of propulsion system augments vortex. Turbofan placed at down stream end of leading-edge vortex system induces vortex to flow into inlet which delays onset of vortex breakdown.

  17. Vortex Lift Augmentation by Suction

    NASA Technical Reports Server (NTRS)

    Taylor, A. H.; Jackson, L. R.; Huffman, J. K.

    1983-01-01

    Lift performance is improved on a 60 degrees swept Gothic wing. Vortex lift at moderate to high angles of attack on highly swept wings used to improve takeoff performance and maneuverability. New design proposed in which suction of propulsion system augments vortex. Turbofan placed at down stream end of leading-edge vortex system induces vortex to flow into inlet which delays onset of vortex breakdown.

  18. Augmented design and analysis of computer experiments: a novel tolerance embedded global optimization approach applied to SWIR hyperspectral illumination design.

    PubMed

    Keresztes, Janos C; John Koshel, R; D'huys, Karlien; De Ketelaere, Bart; Audenaert, Jan; Goos, Peter; Saeys, Wouter

    2016-12-26

    A novel meta-heuristic approach for minimizing nonlinear constrained problems is proposed, which offers tolerance information during the search for the global optimum. The method is based on the concept of design and analysis of computer experiments combined with a novel two phase design augmentation (DACEDA), which models the entire merit space using a Gaussian process, with iteratively increased resolution around the optimum. The algorithm is introduced through a series of cases studies with increasing complexity for optimizing uniformity of a short-wave infrared (SWIR) hyperspectral imaging (HSI) illumination system (IS). The method is first demonstrated for a two-dimensional problem consisting of the positioning of analytical isotropic point sources. The method is further applied to two-dimensional (2D) and five-dimensional (5D) SWIR HSI IS versions using close- and far-field measured source models applied within the non-sequential ray-tracing software FRED, including inherent stochastic noise. The proposed method is compared to other heuristic approaches such as simplex and simulated annealing (SA). It is shown that DACEDA converges towards a minimum with 1 % improvement compared to simplex and SA, and more importantly requiring only half the number of simulations. Finally, a concurrent tolerance analysis is done within DACEDA for to the five-dimensional case such that further simulations are not required.

  19. Comparisons of Mixed-Phase Icing Cloud Simulations with Experiments Conducted at the NASA Propulsion Systems Laboratory

    NASA Technical Reports Server (NTRS)

    Bartkus, Tadas; Tsao, Jen-Ching; Struk, Peter

    2017-01-01

    This paper builds on previous work that compares numerical simulations of mixed-phase icing clouds with experimental data. The model couples the thermal interaction between ice particles and water droplets of the icing cloud with the flowing air of an icing wind tunnel for simulation of NASA Glenn Research Centers (GRC) Propulsion Systems Laboratory (PSL). Measurements were taken during the Fundamentals of Ice Crystal Icing Physics Tests at the PSL tunnel in March 2016. The tests simulated ice-crystal and mixed-phase icing that relate to ice accretions within turbofan engines.

  20. Propulsion Systems Panel deliberations

    NASA Technical Reports Server (NTRS)

    Bianca, Carmelo J.; Miner, Robert; Johnston, Lawrence M.; Bruce, R.; Dennies, Daniel P.; Dickenson, W.; Dreshfield, Robert; Karakulko, Walt; Mcgaw, Mike; Munafo, Paul M.

    1993-01-01

    The Propulsion Systems Panel was established because of the specialized nature of many of the materials and structures technology issues related to propulsion systems. This panel was co-chaired by Carmelo Bianca, MSFC, and Bob Miner, LeRC. Because of the diverse range of missions anticipated for the Space Transportation program, three distinct propulsion system types were identified in the workshop planning process: liquid propulsion systems, solid propulsion systems and nuclear electric/nuclear thermal propulsion systems.

  1. Electric vehicle propulsion alternatives

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.; Schuh, R. M.; Beach, R. F.

    1983-01-01

    Propulsion technology development for electric vehicles is summarized. Analytical studies, technology evaluation, and the development of technology for motors, controllers, transmissions, and complete propulsion systems are included.

  2. Robot-Assisted Surgery for Mandibular Angle Split Osteotomy Using Augmented Reality: Preliminary Results on Clinical Animal Experiment.

    PubMed

    Zhou, Chaozheng; Zhu, Ming; Shi, Yunyong; Lin, Li; Chai, Gang; Zhang, Yan; Xie, Le

    2017-07-19

    Mandibular angle split osteotomy (MASO) is a procedure widely used for prominent mandibular angles. However, conventional mandibular plastic surgery is invasive and high risk. It may induce postoperative neurosensory disturbance of the inferior alveolar nerve, fractures and infection due to the complexity of the anatomical structure and the narrow surgical field of view. The success rate of MASO surgery usually depends on the clinical experience and skills of the surgeon. To evaluate the performance of inexperienced plastic surgeons conducting this surgery, a self-developed and constructed robot system based on augmented reality is used. This robot system provides for sufficient accuracy and safety within the clinical environment. To evaluate the accuracy and safety of MASO surgery, an animal study using this robot was performed in the clinical room, and the results were then evaluated. Four osteotomy planes were successfully performed on two dogs; that is, twenty tunnels (each dog drilled on bilaterally) were drilled in the dogs' mandible bones. Errors at entrance and target points were 1.04 ± 0.19 and 1.22 ± 0.24 mm, respectively. The angular error between the planned and drilled tunnels was 6.69° ± 1.05°. None of the dogs experienced severe complications. Therefore, this technique can be regarded as a useful approach for training inexperienced plastic surgeons on the various aspects of plastic surgery. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  3. Research instrumentation requirements for flight/wind-tunnel tests of the YF-12 propulsion system and related flight experience

    NASA Technical Reports Server (NTRS)

    Schweikhard, W. G.; Montoya, E. J.

    1974-01-01

    Description of the requirements for a comprehensive flight and wind-tunnel propulsion research program to examine the predictability of inlet performance, evaluate the effects of high-frequency pressure phenomena on inlets, and investigate improved control concepts in order to cope with airframe interactions. This program is unique in that it requires precise similarity of the geometry of the flight vehicle and tunnel modes; the test conditions, including local flow at the inlet; and instrumentation. Although few wind-tunnel instrumentation problems exist, many problems emerge during flight tests because of the thermal environment. Mach 3 flight temperatures create unique problems with transducers, connectors, and wires. All must be capable of withstanding continuous 1000 F temperatures, as well as the mechanical stresses imposed by vibration and thermal cycling.

  4. Nuclear gas core propulsion research program

    NASA Technical Reports Server (NTRS)

    Diaz, Nils J.; Dugan, Edward T.; Anghaie, Samim

    1993-01-01

    Viewgraphs on the nuclear gas core propulsion research program are presented. The objectives of this research are to develop models and experiments, systems, and fuel elements for advanced nuclear thermal propulsion rockets. The fuel elements under investigation are suitable for gas/vapor and multiphase fuel reactors. Topics covered include advanced nuclear propulsion studies, nuclear vapor thermal rocket (NVTR) studies, and ultrahigh temperature nuclear fuels and materials studies.

  5. Convective Heat Transfer for Ship Propulsion.

    DTIC Science & Technology

    1982-04-01

    RD-A124 Wi CONVECTIVE HEAT TRANSFER FOR SHIP PROPULSION (U) ARIZONA 112 UNIV TUCSON ENGINEERING EXPERIMENT STATION PARK ET AL. 01 APR 82 1248-9 N814...395 CONVECTIVE HEAT TRANSFER FOR SHIP PROPULSION Prepared for Office of Naval Research Code 431 Arlington, Virginia Prepared by J. S. Park, M. F...FOR SHIP PROPULSION By J. S. Park, M. F. Taylor and D. M. McEligot Aerospace and Mechanical Engineering Department University of Arizona Tucson

  6. Electric propulsion, circa 2000

    NASA Technical Reports Server (NTRS)

    Hudson, W. R.; Finke, R. C.

    1980-01-01

    This paper discusses the future of electric propulsion, circa 2000. Starting with the first generation Solar Electric Propulsion (SEP) technology as the first step toward the next century's advanced propulsion systems, the current status and future trends of other systems such as the magnetoplasmadynamic accelerator, the mass driver, the laser propulsion system, and the rail gun are described.

  7. Free radical propulsion concept

    NASA Technical Reports Server (NTRS)

    Hawkins, C. E.; Nakanishi, S.

    1981-01-01

    The concept of a free radical propulsion system, utilizing the recombination energy of dissociated low molecular weight gases to produce thrust, is analyzed. The system, operating at a theoretical impulse with hydrogen, as high as 2200 seconds at high thrust to power ratio, is hypothesized to bridge the gap between chemical and electrostatic propulsion capabilities. A comparative methodology is outlined by which characteristics of chemical and electric propulsion for orbit raising mission can be investigated. It is noted that free radicals proposed in rockets previously met with difficulty and complexity in terms of storage requirements; the present study proposes to eliminate the storage requirements by using electric energy to achieve a continuous-flow product of free radicals which are recombined to produce a high velocity propellant. Microwave energy used to dissociate a continuously flowing gas is transferred to the propellant via three-body-recombination for conversion to propellant kinetic energy. Microwave plasma discharge was found in excess of 90 percent over a broad range of pressure in preliminary experiments, and microwave heating compared to electrothermal heating showed much higher temperatures in gasdynamic equations.

  8. Human Augmentics: augmenting human evolution.

    PubMed

    Kenyon, Robert V; Leigh, Jason

    2011-01-01

    Human Augmentics (HA) refers to technologies for expanding the capabilities, and characteristics of humans. One can think of Human Augmentics as the driving force in the non-biological evolution of humans. HA devices will provide technology to compensate for human biological limitations either natural or acquired. The strengths of HA lie in its applicability to all humans. Its interoperability enables the formation of ecosystems whereby augmented humans can draw from other realms such as "the Cloud" and other augmented humans for strength. The exponential growth in new technologies portends such a system but must be designed for interaction through the use of open-standards and open-APIs for system development. We discuss the conditions needed for HA to flourish with an emphasis on devices that provide non-biological rehabilitation.

  9. Advanced nuclear propulsion technologies

    SciTech Connect

    Cassenti, B.N. )

    1991-01-01

    Advanced nuclear propulsion can take on several forms. Radioactive thrust sheets directly use the decay of radioactive nuclei to provide propulsion. The fissioning of nuclei has been extensively studied for propulsion both analytically and experimentally. Fusion has been analytically examined as a means of providing propulsion during the last few decades. In the last decade, serious attention has been given to the direct annihilation of matter. Each of these technologies is discussed in this paper with the greatest emphasis on antiproton annihilation propulsion.

  10. Is anastomotic urethroplasty is really superior than BMG augmented dorsal onlay urethroplasty in terms of outcomes and patient satisfaction: Our 4-year experience

    PubMed Central

    Choudhary, Anil Kumar; Jha, Nawal K.

    2015-01-01

    Introduction We analyzed the outcomes of augmented buccal mucosa graft (BMG) dorsal onlay urethroplasty and anastomotic urethroplasty in the management of urethral stricture. Methods: Patients having a stricture length more than 2 cm were treated by augmented BMG dorsal onlay urethroplasty; patients with a stricture length less than 2 cm were managed by excision and end-to-end anastomotic urethroplasty. The postoperative retrograde urethrogram, micturating cystourethrogram, and uroflowmetry were compared to preoperative values. The postoperative subjective symptoms and complications were recorded and analyzed. Results: In total, 90 patients were included in this study. Forty-five patients had an average stricture length of 5.9 cm; they underwent BMG augmented dorsal onlay urethroplasty. Of these, 7 (15.55%) patients came with recurrence, while 38 (84.44%) were asymptomatic, in the average follow-up period of 32.8 months. The next 45 patients underwent excision of the stricture and end-to-end anastomosis. Of these, 6 (13.33%) failed on therapy and the remaining 39 (86.66%) were asymptomatic during the average follow-up period of 28.4 months. Conclusion: The technique of BMG dorsal onlay is easy to do, it is very reliable, has high success rate, less postoperative complications and better patient satisfaction compared to anastomotic urethroplasty. Our study has its limitations. Recurrent cases of urethroplasty and hypospadias were excluded from this study. Recurrent stricture cases were eliminated to overcome bias. Cases of hypospadias are still best treated by axial or random penile skin flap as BMG augmentation cannot create a long urethral tube. Based on our 4-year experience, we recommend BMG augmented urethroplasty long and short segment stricture of the urethra. PMID:25624962

  11. Space propulsion

    NASA Astrophysics Data System (ADS)

    Kazaroff, John M.

    1993-02-01

    Lewis Research Center is developing broad-based new technologies for space chemical engines to satisfy long-term needs of ETO launch vehicles and other vehicles operating in and beyond Earth orbit. Specific objectives are focused on high performance LO2/LH2 engines providing moderate thrusts of 7,5-200 klb. This effort encompasses research related to design analysis and manufacturing processes needed to apply advanced materials to subcomponents, components, and subsystems of space-based systems and related ground-support equipment. High-performance space-based chemical engines face a number of technical challenges. Liquid hydrogen turbopump impellers are often so large that they cannot be machined from a single piece, yet high stress at the vane/shroud interface makes bonding extremely difficult. Tolerances on fillets are critical on large impellers. Advanced materials and fabricating techniques are needed to address these and other issues of interest. Turbopump bearings are needed which can provide reliable, long life operation at high speed and high load with low friction losses. Hydrostatic bearings provide good performance, but transients during pump starts and stops may be an issue because no pressurized fluid is available unless a separate bearing pressurization system is included. Durable materials and/or coatings are needed that can demonstrate low wear in the harsh LO2/LH2 environment. Advanced materials are also needed to improve the lifetime, reliability and performance of other propulsion system elements such as seals and chambers.

  12. Advanced intellect-augmentation techniques

    NASA Technical Reports Server (NTRS)

    Engelbart, D. C.

    1972-01-01

    User experience in applying our augmentation tools and techniques to various normal working tasks within our center is described so as to convey a subjective impression of what it is like to work in an augmented environment. It is concluded that working-support, computer-aid systems for augmenting individuals and teams, are undoubtedly going to be widely developed and used. A very special role in this development is seen for multi-access computer networks.

  13. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

    2001-01-01

    of heating and containing the plasma. Intensive research in developing magnetic energy containment and inertial plasma compression are being pursued in distinctively different fusion experiments in the terrestrial fusion power program. Fusion schemes that attempt to combine the favorable attributes of these two aspects into one single integrated fusion scheme appear to have benefits that are worth exploring for propulsion application.

  14. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

    2001-01-01

    of heating and containing the plasma. Intensive research in developing magnetic energy containment and inertial plasma compression are being pursued in distinctively different fusion experiments in the terrestrial fusion power program. Fusion schemes that attempt to combine the favorable attributes of these two aspects into one single integrated fusion scheme appear to have benefits that are worth exploring for propulsion application.

  15. Certification Testing Approach for Propulsion System Design

    NASA Technical Reports Server (NTRS)

    Rodriguez, Henry; Popp, Chris

    2006-01-01

    The Certification of Propulsion Systems is costly and complex, involving development and qualification testing. The desire of the certification process is to assure all requirements can be demonstrated to be compliant. The purpose of this paper is to address the technical design concerns of certifying a propulsion system for flight. Presented are Pressurization, Tankage, Feed System and Combustion Instability concerns. Propulsion System Engineers are challenged with the dilemma for testing new systems to specific levels to reduce risk yet maintain budgetary targets. A methodical approach is presented to define the types of test suitable to address the technical issues for qualifying systems for retiring the risk levels. Experience of the lessons learned from supporting the Shuttle Program for Main Propulsion and On Orbit Propulsions Systems as well as previous collaborations on design concerns for certifying propulsion systems are utilized to address design concerns and verification approaches.

  16. Comparisons of Mixed-Phase Icing Cloud Simulations with Experiments Conducted at the NASA Propulsion Systems Laboratory

    NASA Technical Reports Server (NTRS)

    Bartkus, Tadas P.; Struk, Peter M.; Tsao, Jen-Ching

    2017-01-01

    This paper builds on previous work that compares numerical simulations of mixed-phase icing clouds with experimental data. The model couples the thermal interaction between ice particles and water droplets of the icing cloud with the flowing air of an icing wind tunnel for simulation of NASA Glenn Research Centers (GRC) Propulsion Systems Laboratory (PSL). Measurements were taken during the Fundamentals of Ice Crystal Icing Physics Tests at the PSL tunnel in March 2016. The tests simulated ice-crystal and mixed-phase icing that relate to ice accretions within turbofan engines. Experimentally measured air temperature, humidity, total water content, liquid and ice water content, as well as cloud particle size, are compared with model predictions. The model showed good trend agreement with experimentally measured values, but often over-predicted aero-thermodynamic changes. This discrepancy is likely attributed to radial variations that this one-dimensional model does not address. One of the key findings of this work is that greater aero-thermodynamic changes occur when humidity conditions are low. In addition a range of mixed-phase clouds can be achieved by varying only the tunnel humidity conditions, but the range of humidities to generate a mixed-phase cloud becomes smaller when clouds are composed of smaller particles. In general, the model predicted melt fraction well, in particular with clouds composed of larger particle sizes.

  17. Augmented Reality Comes to Physics

    ERIC Educational Resources Information Center

    Buesing, Mark; Cook, Michael

    2013-01-01

    Augmented reality (AR) is a technology used on computing devices where processor-generated graphics are rendered over real objects to enhance the sensory experience in real time. In other words, what you are really seeing is augmented by the computer. Many AR games already exist for systems such as Kinect and Nintendo 3DS and mobile apps, such as…

  18. Augmented Reality Comes to Physics

    ERIC Educational Resources Information Center

    Buesing, Mark; Cook, Michael

    2013-01-01

    Augmented reality (AR) is a technology used on computing devices where processor-generated graphics are rendered over real objects to enhance the sensory experience in real time. In other words, what you are really seeing is augmented by the computer. Many AR games already exist for systems such as Kinect and Nintendo 3DS and mobile apps, such as…

  19. Advanced Intellect-Augmentation Techniques.

    ERIC Educational Resources Information Center

    Engelbart, D. C.

    This progress report covers a two-year project which is part of a program that is exploring the value of computer aids in augmenting human intellectual capability. The background and nature of the program, its resources, and the activities it has undertaken are outlined. User experience in applying augmentation tools and techniques to various…

  20. Prophylactic Leukotriene Inhibitor Therapy for the Reduction of Capsular Contracture in Primary Silicone Breast Augmentation: Experience with over 1100 Cases

    PubMed Central

    2017-01-01

    Background: The role of leukotriene inhibitors used immediately postoperatively to potentially influence the development of capsular contracture is unknown. The purpose of this study was to evaluate the incidence of capsular contracture among women undergoing primary smooth silicone gel breast augmentation, with or without postoperative leukotriene inhibitor therapy. Methods: Between 2007 and 2013, 1122 consecutive women undergoing primary silicone gel breast augmentation were evaluated retrospectively. All underwent augmentation with smooth, Mentor Memory Gel implants, using a dual-plane technique, with periareolar or inframammary approaches. Patients were treated voluntarily with either no leukotriene inhibitor, montelukast (Singulair), or zafirlukast (Accolate) for 3 months. All patients received informed consent for the off-label use of leukotriene inhibitors. Liver function studies were obtained for all patients undergoing Accolate therapy after 1 month of therapy. The presence of capsular contracture was measured by the Baker scale at 1 year postoperatively. Results: Patients receiving Accolate therapy (n = 520) demonstrated an encapsulation rate of 2.19 percent. Women receiving Singulair therapy (n = 247) had an encapsulation rate of 3.27 percent. Patients not receiving leukotriene inhibitor therapy had an encapsulation rate of 5.02 percent. There were no long-term complications among patients evaluated. Conclusions: Accolate therapy used for 3 months postoperatively was associated with significantly lower capsular contracture rates compared with untreated patients at 1-year follow-up (p < 0.05). Patients treated with Singulair demonstrated lower contracture rates compared with controls, but the differences were not statistically significant. The findings suggest that Accolate therapy, with monitoring and consent, reduces the incidence of capsular contracture following primary smooth silicone gel breast augmentation. CLINICAL QUESTION/LEVEL OF EVIDENCE

  1. Aripiprazole augmentation in highly treatment-resistant obsessive-compulsive disorder - experience from a specialty clinic in India.

    PubMed

    Hegde, Aditya; Kalyani, Bangalore G; Arumugham, Shyam Sundar; Narayanaswamy, Janardhanan C; Math, Suresh Bada; Reddy, Y C Janardhan

    2017-03-01

    To study the effectiveness and tolerability of aripiprazole augmentation in patients with highly treatment-resistant obsessive-compulsive disorder (OCD) in a real-world scenario. We conducted a chart review of patients who were initiated on aripiprazole augmentation at a specialty OCD clinic in India between 2004 and 2014. Primary outcome measure was all-cause discontinuation. 23 patients were eligible for analysis. Patients had not achieved symptom remission despite a mean of over 3 prior SRI trials. Aripiprazole was continued to be used in seven patients (30%) at the time of last follow-up. Thirteen patients (57%) discontinued the drug due to side effects, and three patients (13%) discontinued aripiprazole citing no improvement. Six patients (26%) were noted to have ≥25% reduction on the Yale-Brown Obsessive-Compulsive Scale. The study demonstrated, in a real-world setting, that aripiprazole may be a useful augmenting agent in a proportion of patients with highly treatment-resistant OCD. However, side effects may lead to premature discontinuation in many of them.

  2. Z-Pinch Fusion Propulsion

    NASA Technical Reports Server (NTRS)

    Miernik, Janie

    2011-01-01

    Fusion-based nuclear propulsion has the potential to enable fast interplanetary transportation. Shorter trips are better for humans in the harmful radiation environment of deep space. Nuclear propulsion and power plants can enable high Ispand payload mass fractions because they require less fuel mass. Fusion energy research has characterized the Z-Pinch dense plasma focus method. (1) Lightning is form of pinched plasma electrical discharge phenomena. (2) Wire array Z-Pinch experiments are commonly studied and nuclear power plant configurations have been proposed. (3) Used in the field of Nuclear Weapons Effects (NWE) testing in the defense industry, nuclear weapon x-rays are simulated through Z-Pinch phenomena.

  3. Workshop on Solar Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Bents, David; Marvin, Dean

    1993-01-01

    A summary of the discussion at the workshop on solar electric propulsion (SEP) is presented. The purpose of ELITE SEP flight experiment is to demonstrate operation of solar array powered electric thrusters for raising spacecraft from parking orbit to higher altitudes, leading to definition of an operational SEP orbit transfer vehicles (OTV) for Air Force missions. Many of the problems or potential problems that may be associated with SEP are not well understood nor clearly identified, and system level phenomena such as interaction of thruster plume with the solar arrays cannot be simulated in a ground test. Therefore, an end-to-end system flight test is required to demonstrate solar electric propulsion.

  4. Beamed energy propulsion

    NASA Technical Reports Server (NTRS)

    Shoji, James M.

    1992-01-01

    Beamed energy concepts offer an alternative for an advanced propulsion system. The use of a remote power source reduces the weight of the propulsion system in flight and this, combined with the high performance, provides significant payload gains. Within the context of this study's baseline scenario, two beamed energy propulsion concepts are potentially attractive: solar thermal propulsion and laser thermal propulsion. The conceived beamed energy propulsion devices generally provide low thrust (tens of pounds to hundreds of pounds); therefore, they are typically suggested for cargo transportation. For the baseline scenario, these propulsion system can provide propulsion between the following nodes: (1) low Earth orbit to geosynchronous Earth orbit; (2) low Earth orbit to low lunar orbit; (3) low lunar orbit to low Mars orbit--only solar thermal; and (4) lunar surface to low lunar orbit--only laser thermal.

  5. Hybrid rocket propulsion

    NASA Technical Reports Server (NTRS)

    Holzman, Allen L.

    1993-01-01

    Topics addressed are: (1) comparison of the theoretical impulses; (2) comparison of the density-specific impulses; (3) general propulsion system features comparison; (4) hybrid systems, booster applications; and (5) hybrid systems, upper stage propulsion applications.

  6. Electrodynamic Tether Propulsion System

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This picture is an artist's concept of an orbiting vehicle using the Electrodynamic Tethers Propulsion System. Relatively short electrodynamic tethers can use solar power to push against a planetary magnetic field to achieve propulsion without the expenditure of propellant.

  7. OTV Propulsion Issues

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The statistical technology needs of aero-assist maneuvering, propulsion, and usage of cryogenic fluids were presented. Industry panels discussed the servicing of reusable space based vehicles and propulsion-vehicle interation.

  8. Uranium ARC Fission Reactor for Space Power and Propulsion

    DTIC Science & Technology

    1992-03-01

    thruster or MHD accelerator/generator. Uranium arc technology is being developed for use in space nuclear thermal and electric propulsion reactors. In...specific impulse propulsion or ultrahigh temperature power conversion. Fission events in the nuclear arc plasma provide for additional dissociation and...I Technical Objectives 3 2. URANIUM ARC FISSION REACTOR CONCEPT AND NUCLEAR -AUGMENTED THRUSTER CONCEPT 4 2.1 Physics Basis 4 2.2 Uranium Arc

  9. Propulsion system ground testing

    NASA Technical Reports Server (NTRS)

    Wood, Charles C.

    1991-01-01

    The objective is to provide management visibility relative to the roles of simulation and propulsion system testing for future development programs through assessment of current propulsion related simulation capabilities and review of contributions from propulsion system test programs. The presentation is represented by viewgraphs.

  10. Directions in propulsion control

    NASA Technical Reports Server (NTRS)

    Lorenzo, Carl F.

    1990-01-01

    Discussed here is research at NASA Lewis in the area of propulsion controls as driven by trends in advanced aircraft. The objective of the Lewis program is to develop the technology for advanced reliable propulsion control systems and to integrate the propulsion control with the flight control for optimal full-system control.

  11. European auxiliary propulsion, 1972

    NASA Technical Reports Server (NTRS)

    Holcomb, L. B.

    1972-01-01

    The chemical and electric auxiliary propulsion technology of the United Kingdom, France, and West Germany is discussed in detail, and the propulsion technology achievements of Italy, India, Japan, and Russia are reviewed. A comparison is presented of Shell 405 catalyst and a European spontaneous hydrazine catalyst called CNESRO I. Finally, conclusions are drawn regarding future trends in European auxiliary propulsion technology development.

  12. Initial clinical experience with a novel vertebral augmentation system for treatment of symptomatic vertebral compression fractures: A case series of 26 consecutive patients

    PubMed Central

    2011-01-01

    Background Minimally invasive vertebral augmentation procedures are widely used to treat vertebral compression fractures although procedural polymethylmethacrylate cement leakage remains common. We report herein our initial experience with a novel vertebral augmentation technique designed to treat symptomatic vertebral osteoporotic fractures and osteolytic metastases with minimal cement extravasation. Methods Forty-two vertebral fractures were identified in 26 consecutive patients (mean age 74 ± 9 years). All patients were treated with a novel percutaneous vertebral augmentation device (Kiva® VCF Treatment System, Benvenue Medical, Santa Clara, CA, USA). Indications for surgery included recent (≤ 3 months) symptomatic osteoporotic vertebral fracture (n = 34) and pathologic vertebral fractures (e.g. metabolic bone disease, myeloma, metastasis) (n = 8) located between T10 and S1. Patient outcomes were evaluated pre-treatment and at 2- and 6-month follow-up visits. Postoperative cement extravasation was assessed with computed tomography. Patient-reported back pain was quantified using an 11-point numeric scale. Back-specific functional disability was self-reported with the Oswestry Disability Index on a 0 to 100% scale. Results No cases of intraoperative hypotension, respiratory disturbance, neurological deterioration, infection, or death were observed. There were 2 (4.8%) levels where anterior cement leakage was visible radiographically in patients with osteolyses. No intracanal leakage was observed. Back pain scores improved 71% (p < 0.001) from pre-treatment to the 6-month follow-up. Back function improved 56% from baseline to 6 months (p < 0.001). Conclusions The initial clinical experience with the Kiva® System demonstrated significant improvements in back pain and function with minimal and clinically insignificant procedural cement leakage. PMID:21939548

  13. Solar Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Gerrish, Harold P., Jr.

    2003-01-01

    This paper presents viewgraphs on Solar Thermal Propulsion (STP). Some of the topics include: 1) Ways to use Solar Energy for Propulsion; 2) Solar (fusion) Energy; 3) Operation in Orbit; 4) Propulsion Concepts; 5) Critical Equations; 6) Power Efficiency; 7) Major STP Projects; 8) Types of STP Engines; 9) Solar Thermal Propulsion Direct Gain Assembly; 10) Specific Impulse; 11) Thrust; 12) Temperature Distribution; 13) Pressure Loss; 14) Transient Startup; 15) Axial Heat Input; 16) Direct Gain Engine Design; 17) Direct Gain Engine Fabrication; 18) Solar Thermal Propulsion Direct Gain Components; 19) Solar Thermal Test Facility; and 20) Checkout Results.

  14. Hydrodynamics of ciliary propulsion

    NASA Astrophysics Data System (ADS)

    Dauptain, A.; Favier, J.; Bottaro, A.

    2008-11-01

    A numerical approach is developed to study the effect on a fluid of the regular oscillations of an array of flexible cilia which hinge around points on a wall. The specific application studied concerns the ctenophore Pleurobrachia pileus, a small marine invertebrate of quasi-spherical shape and diameter of the order of the centimeter which swims in water thanks to the rhythmic beating of eight rows of hair-like cilia aligned along its body. Only one row of cilia is studied here, in a three-dimensional setting. The technique presented is general enough to allow its application to a variety of fluid-structure interaction problems. The physical mechanisms of the propulsion are highlighted, by analysing the results of three-dimensional simulations. A parametric study involving natural and non-natural parameters leads to a better understanding of the propulsive characteristics of ctenophores; results show that the specific power expended increases with the increase of the beating frequency of the row of cilia, in agreement with experiments.

  15. Electromagnetic propulsion for spacecraft

    NASA Technical Reports Server (NTRS)

    Myers, Roger M.

    1993-01-01

    Three electromagnetic propulsion technologies, solid propellant pulsed plasma thrusters (PPT), magnetoplasmadynamic (MPD) thrusters, and pulsed inductive thrusters (PIT), were developed for application to auxiliary and primary spacecraft propulsion. Both the PPT and MPD thrusters were flown in space, though only PPT's were used on operational satellites. The performance of operational PPT's is quite poor, providing only approximately 8 percent efficiency at approximately 1000 s specific impulse. However, laboratory PPT's yielding 34 percent efficiency at 2000 s specific impulse were extensively tested, and peak performance levels of 53 percent efficiency at 5170 s specific impulse were demonstrated. MPD thrusters were flown as experiments on the Japanese MS-T4 spacecraft and the Space Shuttle and were qualified for a flight in 1994. The flight MPD thrusters were pulsed, with a peak performance of 22 percent efficiency at 2500 s specific impulse using ammonia propellant. Laboratory MPD thrusters were demonstrated with up to 70 percent efficiency and 700 s specific impulse using lithium propellant. While the PIT thruster has never been flown, recent performance measurements using ammonia and hydrazine propellants are extremely encouraging, reaching 50 percent efficiency for specific impulses between 4000 to 8000 s. The fundamental operating principles, performance measurements, and system level design for the three types of electromagnetic thrusters are reviewed, and available data on flight tests are discussed for the PPT and MPD thrusters.

  16. NASA electric propulsion technology

    NASA Technical Reports Server (NTRS)

    Berkopec, F. D.; Stone, J. R.; Aston, G.

    1985-01-01

    It is pointed out that the requirements for future electric propulsion cover an extremely large range of technical and programmatic characteristics. A NASA program is to provide options for the many potential mission applications, taking into account work on electrostatic, electromagnetic, and electrothermal propulsion systems. The present paper is concerned with developments regarding the three classes of electric propulsion. Studies concerning electrostatic propulsion are concerned with ion propulsion for primary propulsion for planetary and earth-orbit transfer vehicles, stationkeeping for geosynchronous spacecraft, and ion thruster systems. In connection with investigations related to electromagnetic propulsion, attention is given to electromagnetic launchers, the Hall current thruster, and magnetoplasmadynamic thrusters. In a discussion of electrothermal developments, space station resistojets are considered along with high performance resistojets, arcjets, and a laser thruster.

  17. Antiproton catalyzed microfission/fusion propulsion

    NASA Technical Reports Server (NTRS)

    Chiang, Pi-Ren; Lewis, Raymond A.; Smith, Gerald A.; Newton, Richard; Dailey, James; Werthman, W. Lance; Chakrabarti, Suman

    1994-01-01

    Inertial confinement fusion (ICF) utilizing an antiproton catalyzed hybrid fission/fusion target is discussed as a potential energy source for interplanetary propulsion. A proof-of-principle experiment underway at Phillips Laboratory, Kirtland AFB and antiproton trapping experiments at CERN, Geneva, Switzerland, are presented. The ICAN propulsion concept is described and results of performance analyses are reviewed. Future work to further define the ICAN concept is outlined.

  18. "My World Has Expanded Even Though I'm Stuck at Home": Experiences of Individuals With Amyotrophic Lateral Sclerosis Who Use Augmentative and Alternative Communication and Social Media.

    PubMed

    Caron, Jessica; Light, Janice

    2015-11-01

    This study aimed to expand the current understanding of how persons with amyotrophic lateral sclerosis (pALS) use augmentative and alternative communication and social media to address their communication needs. An online focus group was used to investigate the experiences of 9 pALS who use augmentative and alternative communication and social media. Questions posed to the group related to (a) current use of social media, (b) advantages of social media, (c) barriers to independent use, (d) supports to independent use, and (e) recommendations for developers, policy makers, and other pALS. Participants primarily reported that use of social media was a beneficial tool that provided increased communication opportunities, connections to communication partners, and networks of support. Specific results are discussed with reference to the research as well as implications for practice and recommendations for future research. As individuals with ALS experience loss of function, some communication modes may no longer be viable. Providing access to different modes of communication, including social media, can allow independence, participation and better quality of life.

  19. Thermal Orbital Environmental Parameter Study on the Propulsive Small Expendable Deployer System (ProSEDS) Using Earth Radiation Budget Experiment (ERBE) Data

    NASA Technical Reports Server (NTRS)

    Sharp, John R.; McConnaughey, Paul K. (Technical Monitor)

    2002-01-01

    The natural thermal environmental parameters used on the Space Station Program (SSP 30425) were generated by the Space Environmental Effects Branch at NASA's Marshall Space Flight Center (MSFC) utilizing extensive data from the Earth Radiation Budget Experiment (ERBE), a series of satellites which measured low earth orbit (LEO) albedo and outgoing long-wave radiation. Later, this temporal data was presented as a function of averaging times and orbital inclination for use by thermal engineers in NASA Technical Memorandum TM 4527. The data was not presented in a fashion readily usable by thermal engineering modeling tools and required knowledge of the thermal time constants and infrared versus solar spectrum sensitivity of the hardware being analyzed to be used properly. Another TM was recently issued as a guideline for utilizing these environments (NASA/TM-2001-211221) with more insight into the utilization by thermal analysts. This paper gives a top-level overview of the environmental parameters presented in the TM and a study of the effects of implementing these environments on an ongoing MSFC project, the Propulsive Small Expendable Deployer System (ProSEDS), compared to conventional orbital parameters that had been historically used.

  20. Thermal Orbital Environmental Parameter Study on the Propulsive Small Expendable Deployer System (ProSEDS) Using Earth Radiation Budget Experiment (ERBE) Data

    NASA Astrophysics Data System (ADS)

    Sharp, John R.

    2002-01-01

    The natural thermal environmental parameters used on the Space Station Program (SSP 30425) were generated by the Space Environmental Effects Branch at NASA's Marshall Space Flight Center (MSFC) utilizing extensive data from the Earth Radiation Budget Experiment (ERBE), a series of satellites which measured low earth orbit (LEO) albedo and outgoing long-wave radiation. Later, this temporal data was presented as a function of averaging times and orbital inclination for use by thermal engineers in NASA Technical Memorandum TM 4527. The data was not presented in a fashion readily usable by thermal engineering modeling tools and required knowledge of the thermal time constants and infrared versus solar spectrum sensitivity of the hardware being analyzed to be used properly. Another TM was recently issued as a guideline for utilizing these environments (NASA/TM-2001-211221) with more insight into the utilization by thermal analysts. This paper gives a top-level overview of the environmental parameters presented in the TM and a study of the effects of implementing these environments on an ongoing MSFC project, the Propulsive Small Expendable Deployer System (ProSEDS), compared to conventional orbital parameters that had been historically used.

  1. Endovascular treatment for dural arteriovenous fistula at the foramen magnum: report of five consecutive patients and experience with balloon-augmented transarterial Onyx injection.

    PubMed

    Liang, Guobiao; Gao, Xu; Li, Zhiqing; Wang, Xiaogang; Zhang, Haifeng; Wu, Zhongxue

    2013-05-01

    Foramen magnum dural arteriovenous fistulas (DAVF) with perimedullary venous drainage represent a small minority of intracranial DAVF, and only a number of small series with limited cases have been reported. The purpose of this retrospective study is to summarize experience of transarterial Onyx embolisation in the treatment of these lesions, with emphasis on the balloon-augmented technique. Five consecutive patients with DAVF at the foramen magnum were treated by transarterial embolisation using the Onyx system. Their symptoms included myelopathy (n=4) and SAH (n=1). Suppliers were from the vertebral artery (VA) (n=4), occipital artery (OA) (n=4), and ascending pharyngeal artery (APA) (n=2), with drainage to the perimedullary veins. After catheterization of the dilated supplier, the fistulous connections, proximal draining veins and appropriate distal segment of the feeders of these DAVF were transarterial embolized using Onyx-18. In three patients, balloon-augmented technique was used to assist embolisation. The technical feasibility of the procedure, angiographic results, and clinical outcome were evaluated. In every case, complete obliteration was achieved. Neither intraprocedural vessel rupture nor other procedure-related complications occurred. The results remained stable in all patients on follow-up angiograms (mean, 7.2 months). At the last clinical follow-up (mean, 17.6 months), two patients showed complete resolution of the initial symptoms, and three patients showed significant improvement. We found that Onyx embolisation is a feasible and safe alternative to open surgery in the treatment of selective DAVF at the foramen magnum. The balloon-augmented technique widens indications for transarterial Onyx packing of these lesions, and improved safety of the procedure. Copyright © 2013. Published by Elsevier Masson SAS.

  2. Propulsion Risk Reduction Activities for Nontoxic Cryogenic Propulsion

    NASA Technical Reports Server (NTRS)

    Smith, Timothy D.; Klem, Mark D.; Fisher, Kenneth L.

    2010-01-01

    The Propulsion and Cryogenics Advanced Development (PCAD) Project s primary objective is to develop propulsion system technologies for nontoxic or "green" propellants. The PCAD project focuses on the development of nontoxic propulsion technologies needed to provide necessary data and relevant experience to support informed decisions on implementation of nontoxic propellants for space missions. Implementation of nontoxic propellants in high performance propulsion systems offers NASA an opportunity to consider other options than current hypergolic propellants. The PCAD Project is emphasizing technology efforts in reaction control system (RCS) thruster designs, ascent main engines (AME), and descent main engines (DME). PCAD has a series of tasks and contracts to conduct risk reduction and/or retirement activities to demonstrate that nontoxic cryogenic propellants can be a feasible option for space missions. Work has focused on 1) reducing the risk of liquid oxygen/liquid methane ignition, demonstrating the key enabling technologies, and validating performance levels for reaction control engines for use on descent and ascent stages; 2) demonstrating the key enabling technologies and validating performance levels for liquid oxygen/liquid methane ascent engines; and 3) demonstrating the key enabling technologies and validating performance levels for deep throttling liquid oxygen/liquid hydrogen descent engines. The progress of these risk reduction and/or retirement activities will be presented.

  3. Propulsion Risk Reduction Activities for Non-Toxic Cryogenic Propulsion

    NASA Technical Reports Server (NTRS)

    Smith, Timothy D.; Klem, Mark D.; Fisher, Kenneth

    2010-01-01

    The Propulsion and Cryogenics Advanced Development (PCAD) Project s primary objective is to develop propulsion system technologies for non-toxic or "green" propellants. The PCAD project focuses on the development of non-toxic propulsion technologies needed to provide necessary data and relevant experience to support informed decisions on implementation of non-toxic propellants for space missions. Implementation of non-toxic propellants in high performance propulsion systems offers NASA an opportunity to consider other options than current hypergolic propellants. The PCAD Project is emphasizing technology efforts in reaction control system (RCS) thruster designs, ascent main engines (AME), and descent main engines (DME). PCAD has a series of tasks and contracts to conduct risk reduction and/or retirement activities to demonstrate that non-toxic cryogenic propellants can be a feasible option for space missions. Work has focused on 1) reducing the risk of liquid oxygen/liquid methane ignition, demonstrating the key enabling technologies, and validating performance levels for reaction control engines for use on descent and ascent stages; 2) demonstrating the key enabling technologies and validating performance levels for liquid oxygen/liquid methane ascent engines; and 3) demonstrating the key enabling technologies and validating performance levels for deep throttling liquid oxygen/liquid hydrogen descent engines. The progress of these risk reduction and/or retirement activities will be presented.

  4. The effect of variable practice on wheelchair propulsive efficiency and propulsive timing.

    PubMed

    Yao, W X; Cordova, A; De Sola, W; Hart, C; Yan, A F

    2012-06-01

    The net mechanical efficiency of wheelchair propulsion is very low, approximately 13%. It is necessary to look for effective practice methods to obtain greater output with less energy expenditure during wheelchair propulsions. Literature indicates that variable practice (VP) is more effective than constant practice (CP) in motor-skill learning. However, it is unknown if VP is more effective than CP in improving wheelchair propulsive efficiency. The purpose of the study was to determine how propulsive efficiency and propulsive timing were affected by variable practice and constant practice. This was an observational and experimental study. The experiment was conducted in a well-controlled university research laboratory. A total of 33 able-bodied subjects participated in this study. Participants were randomly placed into one of the three training groups, two constant practice groups and one variable practice group. One constant group practiced wheelchair propulsion on a roller system with a single speed, 30% of the maximum speed, while the other constant group practiced using 55% of the maximum speed. The variable group practiced with both speeds. Three dependent variables, propulsive efficiency, timing, and intercycle variability of the timing, were measured. All groups improved the three dependent variables significantly after the training, and in general the VP group had greater improvement than the others in improving the propulsive efficiency. This study is the first to demonstrate the advantage of the VP over the CP in improving the propulsive efficiency. This finding has great implication for paraplegics because they require greater workloads for upper-extremity activities.

  5. Future spacecraft propulsion

    NASA Technical Reports Server (NTRS)

    Garrison, P. W.; Stocky, J. F.

    1988-01-01

    Propulsion requirements for launch vehicles, upper stages, satellites and platforms, and planetary spacecraft are described from a functional perspective and compared on an energy basis. Mission velocity requirements for a range of missions are presented. A simple model relating optimum exhaust velocity and maximum system delta-V as a function of system-specific energy is developed, which provides insight into the relationship between system performance and various power and propulsion subsystem characteristics. Based on this model, various advanced propulsion options, e.g., the solid-core nuclear rocket and nuclear electric propulsion, are evaluated, and the implications of this analysis for propulsion and power system technology development programs are discussed. The objective of this paper is to provide an overview of future propulsion requirements for the nonspecialist.

  6. Expendable launch vehicle propulsion

    NASA Technical Reports Server (NTRS)

    Fuller, Paul N.

    1991-01-01

    The current status is reviewed of the U.S. Expendable Launch Vehicle (ELV) fleet, the international competition, and the propulsion technology of both domestic and foreign ELVs. The ELV propulsion technology areas where research, development, and demonstration are most needed are identified. These propulsion technology recommendations are based on the work performed by the Commercial Space Transportation Advisory Committee (COMSTAC), an industry panel established by the Dept. of Transportation.

  7. Nuclear propulsion for orbital transfer

    SciTech Connect

    Beale, G.A.; Lawrence, T.J. )

    1989-06-01

    The state of the art in nuclear propulsion for orbital transfer is discussed. Cryogenic propulsion, electric propulsion, solar-thermal propulsion and direct nuclear propulsion are examined in this context. New technologies with exceptional promise are addressed, emphasizing the particle test bed nuclear engine.

  8. Augmented Reality Comes to Physics

    NASA Astrophysics Data System (ADS)

    Buesing, Mark; Cook, Michael

    2013-04-01

    Augmented reality (AR) is a technology used on computing devices where processor-generated graphics are rendered over real objects to enhance the sensory experience in real time. In other words, what you are really seeing is augmented by the computer. Many AR games already exist for systems such as Kinect and Nintendo 3DS and mobile apps, such as Tagwhat and Star Chart (a must for astronomy class). The yellow line marking first downs in a televised football game2 and the enhanced puck that makes televised hockey easier to follow3 both use augmented reality to do the job.

  9. Australian speech-language pathologists' perceptions and experiences of augmentative and alternative communication in early childhood intervention.

    PubMed

    Iacono, Teresa; Cameron, Marnie

    2009-12-01

    Speech-language pathologists (SLPs) working in early childhood intervention are expected to have knowledge and skills across a number of areas and to engage in evidence-based practice. We explored the knowledge and perceptions of SLPs working with young children within Australian early childhood settings about augmentative and alternative communication (AAC), evidence-based practice, and barriers to such practice. Fourteen clinicians participated in group or individual interviews. Thematic analysis of the transcripts of these discussions revealed that they had a broad view of AAC and its benefits. Their reported assessment and intervention approaches reflected best practice as documented in the literature. The exception was in the implementation of family-centred practice. Although the participants involved families in their children's intervention, many appeared to use a directive approach. There was also evidence of struggling with families' negative attitudes about the use of AAC. A major barrier for these clinicians in implementing AAC and best practice was limited time in light of the many demands and expectations. Despite some frustration, these participants were passionate about their work and belief in the benefits of AAC for young children with varied communication difficulties. The results suggest that many expectations placed on clinicians within early childhood intervention settings may fail to take into account the everyday demands on their time, in a context of varied resources and support.

  10. Peer review comments augment diagnostic error characterization and departmental quality assurance: 1-year experience from a children's hospital.

    PubMed

    Iyer, Ramesh S; Swanson, Jonathan O; Otto, Randolph K; Weinberger, Edward

    2013-01-01

    The objective of our study was to categorize radiologist peer review comments and evaluate their functions within the context of a comprehensive quality assurance (QA) program. All randomly entered radiology peer review comments at our institution were compiled over a 1-year period (January 1, 2011, through December 31, 2011). A Web-based commercially available software package was used to query the comments, which were then exported into a spreadsheet. Each comment was then placed into a single most appropriate category based on consensus decision of two board-certified pediatric radiologists. QA scores associated with each comment were recorded. A total of 427 peer review comments were evaluated. The majority of comments (85.9%) were entered voluntarily with QA scores of 1. A classification system was devised that augments traditional error classification. Seven broad comment categories were identified: errors of observation (25.5%), errors of interpretation (5.6%), inadequate patient data gathering (3.7%), errors of communication (9.6%), interobserver variability (21.3%), informational and educational feedback (23.0%), and complimentary (11.2%). Comment-enhanced peer review expands traditional diagnostic error classification, may identify errors that were underscored, provides continuous educational feedback for participants, and promotes a collegial environment.

  11. Field resonance propulsion concept

    NASA Technical Reports Server (NTRS)

    Holt, A. C.

    1979-01-01

    A propulsion concept was developed based on a proposed resonance between coherent, pulsed electromagnetic wave forms, and gravitational wave forms (or space-time metrics). Using this concept a spacecraft propulsion system potentially capable of galactic and intergalactic travel without prohibitive travel times was designed. The propulsion system utilizes recent research associated with magnetic field line merging, hydromagnetic wave effects, free-electron lasers, laser generation of megagauss fields, and special structural and containment metals. The research required to determine potential, field resonance characteristics and to evaluate various aspects of the spacecraft propulsion design is described.

  12. Advanced Propulsion Concepts at the Jet Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    Brophy, J. R.

    1997-01-01

    Current interest in advanced propulsion within NASA and research activities in advanced propulsion concepts at the Jet Propulsion Laboratory are reviewed. The concepts, which include high power plasma thrusters such as lithuim-fueled Lorentz-Force-Accelerators, MEMS-scale propulsion systems, in-situ propellant utilization techniques, fusion propulsion systems and methods of using antimatter, offer the potential for either significantly enhancing space transportation capability as compared with that of traditional chemical propulsion, or enabling ambitious new missions.

  13. Advanced Propulsion Concepts at the Jet Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    Brophy, J. R.

    1997-01-01

    Current interest in advanced propulsion within NASA and research activities in advanced propulsion concepts at the Jet Propulsion Laboratory are reviewed. The concepts, which include high power plasma thrusters such as lithuim-fueled Lorentz-Force-Accelerators, MEMS-scale propulsion systems, in-situ propellant utilization techniques, fusion propulsion systems and methods of using antimatter, offer the potential for either significantly enhancing space transportation capability as compared with that of traditional chemical propulsion, or enabling ambitious new missions.

  14. SDIO Electric Propulsion Objectives and Programs

    DTIC Science & Technology

    1989-07-01

    ASEE Joint Propulsion Conference, Monterey, CA, 10-12 July 1989. Descriptors, Keywords: Space Propulsion Deployment Arcjet Requirement Electricity...maneuvering is creating new EP opportunities. Space experiments involving EP are being planned around two state-of-the-art thruster types: arcjet and ion...research is focused on the NH3 arcjet for the SP-100 flight mission. Demonstrated 30 kW arq’et sustained life (versus ɛ kW demonstrated sustained

  15. "Social Media has Opened a World of 'Open communication:'" experiences of Adults with Cerebral Palsy who use Augmentative and Alternative Communication and Social Media.

    PubMed

    Caron, Jessica; Light, Janice

    2016-01-01

    An online focus group was used to investigate the experiences of nine individuals with cerebral palsy who use augmentative and alternative communication (AAC) and social media. Information was gathered related to (a) advantages of social media, (b) disadvantages of social media, (c) barriers to successful use, (d) supports to successful use, and (e) recommendations for other individuals using AAC, support personnel, policy makers, and technology developers. Participants primarily chose to focus on social media as a beneficial tool and viewed it as an important form of communication. The participants did describe barriers to social media use (e.g., technology). Despite barriers, all the participants in this study took an active role in learning to use social media. The results are discussed as they relate to themes and with reference to published literature.

  16. Eye Gaze Technology as a Form of Augmentative and Alternative Communication for Individuals with Rett Syndrome: Experiences of Families in The Netherlands.

    PubMed

    Townend, Gillian S; Marschik, Peter B; Smeets, Eric; van de Berg, Raymond; van den Berg, Mariёlle; Curfs, Leopold M G

    This paper provides a brief report on families' experiences of eye gaze technology as one form of augmentative and alternative communication (AAC) for individuals with Rett syndrome (RTT), and the advice, training and support they receive in relation to this. An online survey exploring communication and AAC was circulated to 190 Dutch families; of the 67 questionnaires that were returned, 63 had answered questions relating to eye gaze technology. These 63 were analysed according to parameters including: experiences during trial periods and longer-term use; expert knowledge, advice and support; funding; communicative progress; and family satisfaction. 20 respondents were using or had previous experience of using an eye gaze system at the time of the survey, 28 of those with no prior experience wanted to try a system in the future. Following a trial period, 11 systems had been funded through health insurance for long-term use and two families had decided a system was not appropriate for them. Levels of support during trials and following long-term provision varied. Despite frustrations with the technology, satisfaction with the systems was higher than satisfaction with the support. The majority of families reported progress in their child's skills with longer term use. These findings suggest that although eye gaze technologies offer potential to individuals with RTT and their families, greater input from suppliers and knowledgeable AAC professionals is essential for individuals and families to benefit maximally. Higher levels of training and support should be part of the 'package' when an eye gaze system is provided.

  17. "We definitely need an audience": experiences of Twitter, Twitter networks and tweet content in adults with severe communication disabilities who use augmentative and alternative communication (AAC).

    PubMed

    Hemsley, Bronwyn; Dann, Stephen; Palmer, Stuart; Allan, Meredith; Balandin, Susan

    2015-01-01

    The aim of this study was to investigate the Twitter experiences of adults with severe communication disabilities who use augmentative and alternative communication (AAC) to inform Twitter training and further research on the use of Twitter in populations with communication disabilities. This mixed methods research included five adults with severe communication disabilities who use AAC. It combined (a) quantitative analysis of Twitter networks and (b) manual coding of tweets with (c) narrative interviews with participants on their Twitter experiences and results. The five participants who used AAC and Twitter were diverse in their patterns and experiences of using Twitter. Twitter networks reflected interaction with a close-knit network of people rather than with the broader publics on Twitter. Conversational, Broadcast and Pass Along tweets featured most prominently, with limited use of News or Social Presence tweets. Tweets appeared mostly within each participant's micro- or meso-structural layers of Twitter. People who use AAC report positive experiences in using Twitter. Obtaining help in Twitter, and engaging in hashtag communities facilitated higher frequency of tweets and establishment of Twitter networks. Results reflected an inter-connection of participant Twitter networks that might form part of a larger as yet unexplored emergent community of people who use AAC in Twitter.

  18. Preliminary Assessment of Thrust Augmentation of NEP Based Missions

    NASA Technical Reports Server (NTRS)

    Chew, Gilbert; Pelaccio, Dennis G.; Chiroux, Robert; Pervan, Sherry; Rauwolf, Gerald A.; White, Charles

    2005-01-01

    Science Applications International Corporation (SAIC), with support from NASA Marshall Space Flight Center, has conducted a preliminary study to compare options for augmenting the thrust of a conventional nuclear electric propulsion (NEP) system. These options include a novel nuclear propulsion system concept known as Hybrid Indirect Nuclear Propulsion (HINP) and conventional chemical propulsion. The utility and technical feasibility of the HINP concept are assessed, and features and potential of this new in-space propulsion system concept are identified. As part of the study, SAIC developed top-level design tools to model the size and performance of an HINP system, as well as for several chemical propulsion options, including liquid and gelled propellants. A mission trade study was performed to compare a representative HINP system with chemical propulsion options for thrust augmentation of NEP systems for a mission to Saturn's moon Titan. Details pertaining to the approach, features, initial demonstration results for HINP model development, and the mission trade study are presented. Key technology and design issues associated with the HINP concept and future work recommendations are also identified.

  19. Results of Evaluation of Solar Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon; Byers, Dave

    2003-01-01

    The solar thermal propulsion evaluation reported here relied on prior research for all information on solar thermal propulsion technology and performance. Sources included personal contacts with experts in the field in addition to published reports and papers. Mission performance models were created based on this information in order to estimate performance and mass characteristics of solar thermal propulsion systems. Mission analysis was performed for a set of reference missions to assess the capabilities and benefits of solar thermal propulsion in comparison with alternative in-space propulsion systems such as chemical and electric propulsion. Mission analysis included estimation of delta V requirements as well as payload capabilities for a range of missions. Launch requirements and costs, and integration into launch vehicles, were also considered. The mission set included representative robotic scientific missions, and potential future NASA human missions beyond low Earth orbit. Commercial communications satellite delivery missions were also included, because if STP technology were selected for that application, frequent use is implied and this would help amortize costs for technology advancement and systems development. A C3 Topper mission was defined, calling for a relatively small STP. The application is to augment the launch energy (C3) available from launch vehicles with their built-in upper stages. Payload masses were obtained from references where available. The communications satellite masses represent the range of payload capabilities for the Delta IV Medium and/or Atlas launch vehicle family. Results indicated that STP could improve payload capability over current systems, but that this advantage cannot be realized except in a few cases because of payload fairing volume limitations on current launch vehicles. It was also found that acquiring a more capable (existing) launch vehicle, rather than adding an STP stage, is the most economical in most cases.

  20. Propulsion Controlled Aircraft design and development

    NASA Technical Reports Server (NTRS)

    Wells, Edward A.; Urnes, James M., Sr.

    1995-01-01

    This paper describes the design, development, and ground testing of the propulsion controlled aircraft (PCA) flight control system. A backup flight control system which uses only engine thrust, the PCA system utilizes collective and differential thrust changes to steer an aircraft that experiences partial or complete failure of the hydraulically actuated control surfaces. The objective of the program was to investigate, in flight, the throttles-only control capability of the F-15, using manual control, and also an augmented PCA mode in which computer-controlled thrust was used for flight control. The objective included PCA operation in up-and-away flight and, if performance was adequate, a secondary objective to make actual PCA landings. The PCA design began with a feasibility study which evaluated many control law designs. The study was done using off-line control analysis, simulation, and on-line manned flight simulator tests. Control laws, cockpit displays, and cockpit controls were evaluated by NASA test pilots. A flight test baseline configuration was selected based on projected flight performance, applicability to transport and fighter aircraft, and funding costs. During the PCA software and hardware development, the initial design was updated as data became available from throttle-only flight experiments conducted by NASA on the F-15. This information showed basic airframe characteristics that were not observed in the F-15 flight simulator and resulted in several design changes. After the primary objectives of the PCA flight testing were accomplished, additional PCA modes of operation were developed and implemented. The evolution of the PCA system from the initial feasibility study, control law design, simulation, hardware-in-the-loop tests, pilot-in-the-loop tests, and ground tests is presented.

  1. Electric Propulsion Apparatus

    NASA Technical Reports Server (NTRS)

    Patterson, Michael J. (Inventor)

    2013-01-01

    An electric propulsion machine includes an ion thruster having an annular discharge chamber housing an anode having a large surface area. The ion thruster includes flat annular ion optics with a small span to gap ratio. Optionally, a second electric propulsion thruster may be disposed in a cylindrical space disposed within an interior of the annulus.

  2. Advanced nuclear propulsion concepts

    SciTech Connect

    Howe, S.D.

    1994-12-31

    A preliminary analysis has been carried out for two potential advanced nuclear propulsion systems: a contained pulsed nuclear propulsion engine and an antiproton initiated ICF system. The results of these studies indicate that both concepts have a high potential to help enable manned planetary exploration but require substantial development.

  3. NASA's Propulsion Research Laboratory

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The grand opening of NASA's new, world-class laboratory for research into future space transportation technologies located at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama, took place in July 2004. The state-of-the-art Propulsion Research Laboratory (PRL) serves as a leading national resource for advanced space propulsion research. Its purpose is to conduct research that will lead to the creation and development of innovative propulsion technologies for space exploration. The facility is the epicenter of the effort to move the U.S. space program beyond the confines of conventional chemical propulsion into an era of greatly improved access to space and rapid transit throughout the solar system. The laboratory is designed to accommodate researchers from across the United States, including scientists and engineers from NASA, the Department of Defense, the Department of Energy, universities, and industry. The facility, with 66,000 square feet of useable laboratory space, features a high degree of experimental capability. Its flexibility allows it to address a broad range of propulsion technologies and concepts, such as plasma, electromagnetic, thermodynamic, and propellant propulsion. An important area of emphasis is the development and utilization of advanced energy sources, including highly energetic chemical reactions, solar energy, and processes based on fission, fusion, and antimatter. The Propulsion Research Laboratory is vital for developing the advanced propulsion technologies needed to open up the space frontier, and sets the stage of research that could revolutionize space transportation for a broad range of applications.

  4. NASA's Propulsion Research Laboratory

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The grand opening of NASA's new, world-class laboratory for research into future space transportation technologies located at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama, took place in July 2004. The state-of-the-art Propulsion Research Laboratory (PRL) serves as a leading national resource for advanced space propulsion research. Its purpose is to conduct research that will lead to the creation and development of innovative propulsion technologies for space exploration. The facility is the epicenter of the effort to move the U.S. space program beyond the confines of conventional chemical propulsion into an era of greatly improved access to space and rapid transit throughout the solar system. The laboratory is designed to accommodate researchers from across the United States, including scientists and engineers from NASA, the Department of Defense, the Department of Energy, universities, and industry. The facility, with 66,000 square feet of useable laboratory space, features a high degree of experimental capability. Its flexibility allows it to address a broad range of propulsion technologies and concepts, such as plasma, electromagnetic, thermodynamic, and propellant propulsion. An important area of emphasis is the development and utilization of advanced energy sources, including highly energetic chemical reactions, solar energy, and processes based on fission, fusion, and antimatter. The Propulsion Research Laboratory is vital for developing the advanced propulsion technologies needed to open up the space frontier, and sets the stage of research that could revolutionize space transportation for a broad range of applications.

  5. Advanced Chemical Propulsion

    NASA Technical Reports Server (NTRS)

    Alexander, Leslie, Jr.

    2006-01-01

    Advanced Chemical Propulsion (ACP) provides near-term incremental improvements in propulsion system performance and/or cost. It is an evolutionary approach to technology development that produces useful products along the way to meet increasingly more demanding mission requirements while focusing on improving payload mass fraction to yield greater science capability. Current activities are focused on two areas: chemical propulsion component, subsystem, and manufacturing technologies that offer measurable system level benefits; and the evaluation of high-energy storable propellants with enhanced performance for in-space application. To prioritize candidate propulsion technology alternatives, a variety of propulsion/mission analyses and trades have been conducted for SMD missions to yield sufficient data for investment planning. They include: the Advanced Chemical Propulsion Assessment; an Advanced Chemical Propulsion System Model; a LOx-LH2 small pumps conceptual design; a space storables propellant study; a spacecraft cryogenic propulsion study; an advanced pressurization and mixture ratio control study; and a pump-fed vs. pressure-fed study.

  6. Nuclear thermal propulsion

    NASA Technical Reports Server (NTRS)

    Bennett, Gary L.

    1991-01-01

    This document is presented in viewgraph form, and the topics covered include the following: (1) the direct fission-thermal propulsion process; (2) mission applications of direct fission-thermal propulsion; (3) nuclear engines for rocket vehicles; (4) manned mars landers; and (5) particle bed reactor design.

  7. Experiments on interactions between zirconium-containing melt and water (ZREX): Hydrogen generation and chemical augmentation of energetics

    SciTech Connect

    Cho, D.H.; Armstrong, D.R.; Gunther, W.H.; Basu, S.

    1997-08-01

    The results of the first data series of experiments on interactions between zirconium-containing melt and water are described. These experiments involved dropping 1-kg batches of pure zirconium or zirconium-zirconium dioxide mixture melt into a column of water. A total of nine tests were conducted, including four with pure zirconium melt and five with Zr-ZrO{sub 2} mixture melt. Explosions took place only in those tests which were externally triggered. While the extent of zirconium oxidation in the triggered experiments was quite extensive, the estimated explosion energetics were found to be very small compared to the combined thermal and chemical energy available.

  8. Electric propulsion system technology

    NASA Astrophysics Data System (ADS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

    1992-11-01

    The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of

  9. Electric propulsion system technology

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

    1992-01-01

    The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of

  10. Electrodynamic Tethers for Spacecraft Propulsion

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Estes, Robert D.; Lorenzini, Enrico; Martinez-Sanchez, Manuel; Sanmartin, Juan; Vas, Irwin

    1998-01-01

    Relatively short electrodynamic tethers can use solar power to 'push' against a planetary magnetic field to achieve propulsion without the expenditure of propellant. The groundwork has been laid for this type of propulsion. NASA began developing tether technology for space applications in the 1960's. Important recent milestones include retrieval of a tether in space (TSS-1, 1992), successful deployment of a 20-km-long tether in space (SEDS-1, 1993), and operation of an electrodynamic tether with tether current driven in both directions-power and thrust modes (PMG, 1993). The planned Propulsive Small Expendable Deployer System (ProSEDS) experiment will demonstrate electrodynamic tether thrust during its flight in early 2000. ProSEDS will use the flight-proven Small Expendable Deployer System (SEDS) to deploy a 5 km bare copper tether from a Delta II upper stage to achieve approximately 0.4 N drag thrust, thus deorbiting the stage. The experiment will use a predominantly 'bare' tether for current collection in lieu of the endmass collector and insulated tether approach used on previous missions. Theory and ground-based plasma chamber testing indicate that the bare tether is a highly-efficient current collector. The flight experiment is a precursor to utilization of the technology on the International Space Station for reboost application and the more ambitious electrodynamic tether upper stage demonstration mission which will be capable of orbit raising, lowering and inclination changes - all using electrodynamic thrust. In addition, the use of this type of propulsion may be attractive for future missions at Jupiter and any other planetary body with a magnetosphere.

  11. High Power Helicon Propulsion Experiments

    NASA Astrophysics Data System (ADS)

    Ziemba, Timothy; Slough, John; Winglee, Robert

    2005-02-01

    The High Power Helicon (HPH) under development at the University of Washington may have an attractive application as an electrode-less in-space thruster. Output plasma characteristics show that plasma is created in and near the helicon coil and is accelerated by a helicon induced axial potential downstream away from the HPH. The bulk acceleration of the plasma is believed to be due to a coupling of the plasma electrons to the helicon field, which in turn transfers energy to the ions via an ambipolar electric field. Downstream electric potentials of greater than 150 volts having been measured with the amplitude of the electric field being dependent on experimentally controlled parameters. Time of flight measurements of the plasma transiting downstream show specific impulses (Isp) near 2000 seconds for Argon with calculated thrust levels near 1 Newton for input powers to the plasma in the tens of kilowatts. The system is capable of using different neutral gases as propellants with nitrogen and hydrogen having baseline Isp levels of 3000 and 5000 seconds respectfully giving some variability in Isp and thrust by the choice of propellants. Current work focuses on the determination and optimization of the system efficiencies and increasing output power levels.

  12. A Review of Laser Ablation Propulsion

    SciTech Connect

    Phipps, Claude; Bohn, Willy; Lippert, Thomas; Sasoh, Akihiro; Schall, Wolfgang; Sinko, John

    2010-10-08

    Laser Ablation Propulsion is a broad field with a wide range of applications. We review the 30-year history of laser ablation propulsion from the transition from earlier pure photon propulsion concepts of Oberth and Saenger through Kantrowitz's original laser ablation propulsion idea to the development of air-breathing 'Lightcraft' and advanced spacecraft propulsion engines. The polymers POM and GAP have played an important role in experiments and liquid ablation fuels show great promise. Some applications use a laser system which is distant from the propelled object, for example, on another spacecraft, the Earth or a planet. Others use a laser that is part of the spacecraft propulsion system on the spacecraft. Propulsion is produced when an intense laser beam strikes a condensed matter surface and produces a vapor or plasma jet. The advantages of this idea are that exhaust velocity of the propulsion engine covers a broader range than is available from chemistry, that it can be varied to meet the instantaneous demands of the particular mission, and that practical realizations give lower mass and greater simplicity for a payload delivery system. We review the underlying theory, buttressed by extensive experimental data. The primary problem in laser space propulsion theory has been the absence of a way to predict thrust and specific impulse over the transition from the vapor to the plasma regimes. We briefly discuss a method for combining two new vapor regime treatments with plasma regime theory, giving a smooth transition from one regime to the other. We conclude with a section on future directions.

  13. A Review of Laser Ablation Propulsion

    NASA Astrophysics Data System (ADS)

    Phipps, Claude; Bohn, Willy; Lippert, Thomas; Sasoh, Akihiro; Schall, Wolfgang; Sinko, John

    2010-10-01

    Laser Ablation Propulsion is a broad field with a wide range of applications. We review the 30-year history of laser ablation propulsion from the transition from earlier pure photon propulsion concepts of Oberth and Sänger through Kantrowitz's original laser ablation propulsion idea to the development of air-breathing "Lightcraft" and advanced spacecraft propulsion engines. The polymers POM and GAP have played an important rôle in experiments and liquid ablation fuels show great promise. Some applications use a laser system which is distant from the propelled object, for example, on another spacecraft, the Earth or a planet. Others use a laser that is part of the spacecraft propulsion system on the spacecraft. Propulsion is produced when an intense laser beam strikes a condensed matter surface and produces a vapor or plasma jet. The advantages of this idea are that exhaust velocity of the propulsion engine covers a broader range than is available from chemistry, that it can be varied to meet the instantaneous demands of the particular mission, and that practical realizations give lower mass and greater simplicity for a payload delivery system. We review the underlying theory, buttressed by extensive experimental data. The primary problem in laser space propulsion theory has been the absence of a way to predict thrust and specific impulse over the transition from the vapor to the plasma regimes. We briefly discuss a method for combining two new vapor regime treatments with plasma regime theory, giving a smooth transition from one regime to the other. We conclude with a section on future directions.

  14. Breakthrough Propulsion Physics Workshop Preliminary Results

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    1997-01-01

    In August, 1997, a NASA workshop was held to assess the prospects emerging from physics that might lead to creating the ultimate breakthroughs in space transportation: propulsion that requires no propellant mass, attaining the maximum transit speeds physically possible, and breakthrough methods of energy production to power such devices. Because these propulsion goals are presumably far from fruition, a special emphasis was to identify affordable, near-term, and credible research that could make measurable progress toward these propulsion goals. Experiments and theories were discussed regarding the coupling of gravity and electromagnetism, vacuum fluctuation energy, warp drives and wormholes, and superluminal quantum tunneling. Preliminary results of this workshop are presented, along with the status of the Breakthrough Propulsion Physics program that conducted this workshop.

  15. Breakthrough propulsion physics workshop preliminary results

    SciTech Connect

    Millis, Marc G.

    1998-01-15

    In August, 1997, a NASA workshop was held to assess the prospects emerging from physics that might lead to creating the ultimate breakthroughs in space transportation: propulsion that requires no propellant mass, attaining the maximum transit speeds physically possible, and breakthrough methods of energy production to power such devices. Because these propulsion goals are presumably far from fruition, a special emphasis was to identify affordable, near-term, and credible research that could make measurable progress toward these propulsion goals. Experiments and theories were discussed regarding the coupling of gravity and electromagnetism, vacuum fluctuation energy, warp drives and wormholes, and superluminal quantum tunneling. Preliminary results of this workshop are presented, along with the status of the Breakthrough Propulsion Physics program that conducted this workshop.

  16. Conceptual designs for antiproton space propulsion systems

    SciTech Connect

    Cassenti, B.N.

    1989-01-01

    Five conceptual designs for antimatter space propulsion systems were compared in terms of their performance characteristics. The systems examined included solid-core liquid-propellant rockets; magnetically confined gaseous-core rockets using liquid or solid propellants; plasma-core rockets; pion rockets, which are driven directly by the mass annihilation products; and ram-augmented rockets, in which antiproton annihilation is used to heat hydrogen collected in interstellar space. It was found that, in general, as the specific impulse of the propulsion system increases, the thrust decreases. The comparison between designs showed that only fusion rockets have the capability to compete in performance with mass annihilation rockets. For very-high-speed interstellar missions, pion rockets, which can have a specific impulse of 20 million sec (although with a thrust-to-engine mass ratios of only 0.01 G) will offer best performance. 36 refs.

  17. Laser Ablation Propulsion A Study

    NASA Astrophysics Data System (ADS)

    Irfan, Sayed A.; Ugalatad, Akshata C.

    Laser Ablation Propulsion (LAP) will serve as an alternative propulsion system for development of microthrusters. The principle of LAP is that when a laser (pulsed or continuous wave) with sufficient energy (more than the vaporization threshold energy of material) is incident on material, ablation or vaporization takes place which leads to the generation of plasma. The generated plasma has the property to move away from the material hence pressure is generated which leads to the generation of thrust. Nowadays nano satellites are very common in different space and defence applications. It is important to build micro thruster which are useful for orienting and re-positioning small aircraft (like nano satellites) above the atmosphere. modelling of LAP using MATLAB and Mathematica. Schematic is made for the suitable optical configuration of LAP. Practical experiments with shadowgraphy and self emission techniques and the results obtained are analysed taking poly (vinyl-chloride) (PVC) as propellant to study the

  18. Propulsion Research and Technology: Overview

    NASA Technical Reports Server (NTRS)

    Cole, John; Schmidt, George

    1999-01-01

    Propulsion is unique in being the main delimiter on how far and how fast one can travel in space. It is the lack of truly economical high-performance propulsion systems that continues to limit and restrict the extent of human endeavors in space. Therefore the goal of propulsion research is to conceive and investigate new, revolutionary propulsion concepts. This presentation reviews the development of new propulsion concepts. Some of these concepts are: (1) Rocket-based Combined Cycle (RBCC) propulsion, (2) Alternative combined Cycle engines suc2 as the methanol ramjet , and the liquid air cycle engines, (3) Laser propulsion, (4) Maglifter, (5) pulse detonation engines, (6) solar thermal propulsion, (7) multipurpose hydrogen test bed (MHTB) and other low-G cryogenic fluids, (8) Electric propulsion, (9) nuclear propulsion, (10) Fusion Propulsion, and (11) Antimatter technology. The efforts of the NASA centers in this research is also spotlighted.

  19. Futuristic systems: Solar and nuclear electric propulsion

    NASA Technical Reports Server (NTRS)

    Byers, Dave

    1991-01-01

    The following topics are addressed: (1) in-space propulsion impacts; (2) electric propulsion; (3) mission impacts of electric propulsion; and (4) summaries of electric propulsion status and solar and nuclear propulsion.

  20. Distributed Propulsion Vehicles

    NASA Technical Reports Server (NTRS)

    Kim, Hyun Dae

    2010-01-01

    Since the introduction of large jet-powered transport aircraft, the majority of these vehicles have been designed by placing thrust-generating engines either under the wings or on the fuselage to minimize aerodynamic interactions on the vehicle operation. However, advances in computational and experimental tools along with new technologies in materials, structures, and aircraft controls, etc. are enabling a high degree of integration of the airframe and propulsion system in aircraft design. The National Aeronautics and Space Administration (NASA) has been investigating a number of revolutionary distributed propulsion vehicle concepts to increase aircraft performance. The concept of distributed propulsion is to fully integrate a propulsion system within an airframe such that the aircraft takes full synergistic benefits of coupling of airframe aerodynamics and the propulsion thrust stream by distributing thrust using many propulsors on the airframe. Some of the concepts are based on the use of distributed jet flaps, distributed small multiple engines, gas-driven multi-fans, mechanically driven multifans, cross-flow fans, and electric fans driven by turboelectric generators. This paper describes some early concepts of the distributed propulsion vehicles and the current turboelectric distributed propulsion (TeDP) vehicle concepts being studied under the NASA s Subsonic Fixed Wing (SFW) Project to drastically reduce aircraft-related fuel burn, emissions, and noise by the year 2030 to 2035.

  1. Advanced Propulsion Research Interest in Materials for Propulsion

    NASA Technical Reports Server (NTRS)

    Cole, John

    2003-01-01

    This viewgraph presentation provides an overview of material science and technology in the area of propulsion energetics. The authors note that conventional propulsion systems are near peak performance and further refinements in manufacturing, engineering design and materials will only provide incremental increases in performance. Energetic propulsion technologies could potential solve the problems of energy storage density and energy-to-thrust conversion efficiency. Topics considered include: the limits of thermal propulsion systems, the need for energetic propulsion research, emerging energetic propulsion technologies, materials research needed for advanced propulsion, and potential research opportunities.

  2. Bionic Propulsion on Water and Measurement of Propulsion

    NASA Astrophysics Data System (ADS)

    Yun, Liu; Si-yuan, Zhao; Shan-chao, Tu; Tian-yu, Zhu; Rong-xiang, Li

    Traditional propulsion fashion on water are propeller propulsion and jet propulsion, but the efficiency relatively low. Used by biological propulsion, after the last million years of evolution, the maximum utilization of its power. Bionic propulsion system designed in this paper consists of two large travel umbrella wing plate in reciprocating linear travel agencies, led by the reciprocating motion along the vertical, in the water under the influence of backward movement of the wing disk automatically open, resulting in the pull forward, the forward movement of the wing disk automatically shut down to reduce water resistance. This paper designs a bionic propulsion and drag model for the static test and measurement test propulsion.

  3. Nuclear Cryogenic Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Borowski, S. K.; George, J. A.; Kim, T.; Emrich, W. J.; Hickman, R. R.; Broadway, J. W.; Gerrish, H. P.; Adams, R. B.

    2012-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced NEP.

  4. Ion propulsion cost effectivity

    NASA Technical Reports Server (NTRS)

    Zafran, S.; Biess, J. J.

    1978-01-01

    Ion propulsion modules employing 8-cm thrusters and 30-cm thrusters were studied for Multimission Modular Spacecraft (MMS) applications. Recurring and nonrecurring cost elements were generated for these modules. As a result, ion propulsion cost drivers were identified to be Shuttle charges, solar array, power processing, and thruster costs. Cost effective design approaches included short length module configurations, array power sharing, operation at reduced thruster input power, simplified power processing units, and power processor output switching. The MMS mission model employed indicated that nonrecurring costs have to be shared with other programs unless the mission model grows. Extended performance missions exhibited the greatest benefits when compared with monopropellant hydrazine propulsion.

  5. Electric Propulsion Study

    DTIC Science & Technology

    1990-08-01

    DTIC FILE COPY AL-TR-89-040 AD: AD-A227 121 Final Report forteprod Electric Propulsion Study 21 Sep 1988 to 30 Nov 1989 DTIC ’ELECTE0OCT 0c 41990u... Electric Propulsion Study (U) 12. PERSONAL AUTHOR(S) Cravens, Dennis J. 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year, Month, Day) 15. PAGE...identif bv block number) FIELD GROUP SUB-GROUP Inductive theories, electric propulsion, unified field 21 0- theories, Conservatc!±,n Laws, Dynamic

  6. Advanced Propulsion Study

    DTIC Science & Technology

    2004-02-01

    G . L ., Forward, R. L . and Frisbee, R. H. (1995a), “Report on the NASA/JPL Workshop on Advanced Quantum/Relativity Theory Propulsion,” AIAA-95-2599...31st AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, San Diego, CA 19. Bennett, G . L ., Forward, R. L . and Frisbee, R. H. (1995b...Propulsion Conference, Indianapolis, IN 169. Mead, F. B., Myrabo, L . N., and Messitt, D. G . (1998), “Flight and Ground Tests of a Laser-Boosted Vehicle

  7. History of gluteal augmentation.

    PubMed

    de la Peña, J Abel; Rubio, Omar V; Cano, Jacobo P; Cedillo, Mariana C; Garcés, Miriam T

    2006-07-01

    The concept of female beauty has changed throughout time, but the form and size of the breasts and gluteal region have remained constant as symbols of maximum femininity. Sculptures and prints show us feminine figures that are voluminous and reflect human history's interest in fertility. The early years of gluteal augmentation saw few published reports that described the procedure technique, follow-up, or possible complications. But developments continued as surgeons began experimenting with different anatomical planes for implant placement. The most important goal in plastic surgery is meeting a patient's expectations. It is important for the surgeon to thoroughly explain to patients what can realistically be achieved with a procedure.

  8. “We definitely need an audience”: experiences of Twitter, Twitter networks and tweet content in adults with severe communication disabilities who use augmentative and alternative communication (AAC)

    PubMed Central

    Hemsley, Bronwyn; Dann, Stephen; Palmer, Stuart; Allan, Meredith; Balandin, Susan

    2015-01-01

    Abstract Purpose: The aim of this study was to investigate the Twitter experiences of adults with severe communication disabilities who use augmentative and alternative communication (AAC) to inform Twitter training and further research on the use of Twitter in populations with communication disabilities. Method: This mixed methods research included five adults with severe communication disabilities who use AAC. It combined (a) quantitative analysis of Twitter networks and (b) manual coding of tweets with (c) narrative interviews with participants on their Twitter experiences and results. Results: The five participants who used AAC and Twitter were diverse in their patterns and experiences of using Twitter. Twitter networks reflected interaction with a close-knit network of people rather than with the broader publics on Twitter. Conversational, Broadcast and Pass Along tweets featured most prominently, with limited use of News or Social Presence tweets. Tweets appeared mostly within each participant's micro- or meso-structural layers of Twitter. Conclusions: People who use AAC report positive experiences in using Twitter. Obtaining help in Twitter, and engaging in hashtag communities facilitated higher frequency of tweets and establishment of Twitter networks. Results reflected an inter-connection of participant Twitter networks that might form part of a larger as yet unexplored emergent community of people who use AAC in Twitter.Implications for RehabilitationTwitter can be used as an important vehicle for conversation and a forum for people with communication disabilities to exchange information and participate socially in online communities.It is important that information and resources relating to the effective use of Twitter for a range of purposes are made available to people with communication disabilities who wish to take up or maintain use of Twitter.People with communication disabilities might benefit from support in using Twitter to meet their goals

  9. Xenon ion propulsion for orbit transfer

    NASA Technical Reports Server (NTRS)

    Rawlin, V. K.; Patterson, M. J.; Gruber, R. P.

    1990-01-01

    For more than 30 years, NASA has conducted an ion propulsion program which has resulted in several experimental space flight demonstrations and the development of many supporting technologies. Technologies appropriate for geosynchronous stationkeeping, earth-orbit transfer missions, and interplanetary missions are defined and evaluated. The status of critical ion propulsion system elements is reviewed. Electron bombardment ion thrusters for primary propulsion have evolved to operate on xenon in the 5 to 10 kW power range. Thruster efficiencies of 0.7 and specific impulse values of 4000 s were documented. The baseline thruster currently under development by NASA LeRC includes ring-cusp magnetic field plasma containment and dished two-grid ion optics. Based on past experience and demonstrated simplifications, power processors for these thrusters should have approximately 500 parts, a mass of 40 kg, and an efficiency near 0.94. Thrust vector control, via individual thruster gimbals, is a mature technology. High pressure, gaseous xenon propellant storage and control schemes, using flight qualified hardware, result in propellant tankage fractions between 0.1 and 0.2. In-space and ground integration testing has demonstrated that ion propulsion systems can be successfully integrated with their host spacecraft. Ion propulsion system technologies are mature and can significantly enhance and/or enable a variety of missions in the nation's space propulsion program.

  10. Solar Electric Propulsion (SEP)

    NASA Image and Video Library

    Future Human Exploration requires high power solar electric propulsion vehicles to move cargo and humans beyond Low Earth Orbit, which requires large light weight arrays, high power processing, and...

  11. Nuclear Thermal Propulsion (NTP)

    NASA Image and Video Library

    NASA's history with nuclear thermal propulsion (NTP) technology goes back to the earliest days of the Agency. The Manned Lunar Rover Vehicle and the Nuclear Engine for Rocket Vehicle Applications p...

  12. Spacecraft propulsion: new methods.

    PubMed

    Alfvén, H

    1972-04-14

    Cosmic plasmas contain energy which may be tapped and used for spacecraft propulsion. The energy needed for launching a spacecraft could be supplied to it from the ground through a plasma channel in the atmosphere.

  13. Propulsion technology discipline

    NASA Technical Reports Server (NTRS)

    Jones, Lee W.

    1990-01-01

    Viewgraphs on propulsion technology discipline for Space Station Freedom are presented. Topics covered include: water electrolysis O2/H2 system; hydrazine system advancements; common technology; fluids disposal; and storable bipropellant system.

  14. Solar Thermal Rocket Propulsion

    NASA Technical Reports Server (NTRS)

    Sercel, J. C.

    1986-01-01

    Paper analyzes potential of solar thermal rockets as means of propulsion for planetary spacecraft. Solar thermal rocket uses concentrated Sunlight to heat working fluid expelled through nozzle to produce thrust.

  15. Electric propulsion system technology

    NASA Astrophysics Data System (ADS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.

    1991-12-01

    model enables one to calculate the flow direction and local density of the charge exchange plasma, and indicates the degree to which this plasma can flow upstream of the thruster exhaust plane. A continuing effort to investigate the most desirable throttling technique for noble gas ion thrusters concentrated this year on experimentally determining the fixed flow rate throttling range of a 30-cm dia. thruster with a two-grid accelerator system. These experiments demonstrated a throttling capability which covers a 2.8 to 1 variation in input power. This throttling range is 55 percent greater than expected, and is due to better accelerator system performance at low net-to-total voltage ratios than indicated in the literature. To facilitate the development of large, higher power ion thrusters several brief studies were performed. propulsion for the Space Exploration Initiative was written.

  16. Electric propulsion system technology

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.

    1991-01-01

    model enables one to calculate the flow direction and local density of the charge exchange plasma, and indicates the degree to which this plasma can flow upstream of the thruster exhaust plane. A continuing effort to investigate the most desirable throttling technique for noble gas ion thrusters concentrated this year on experimentally determining the fixed flow rate throttling range of a 30-cm dia. thruster with a two-grid accelerator system. These experiments demonstrated a throttling capability which covers a 2.8 to 1 variation in input power. This throttling range is 55 percent greater than expected, and is due to better accelerator system performance at low net-to-total voltage ratios than indicated in the literature. To facilitate the development of large, higher power ion thrusters several brief studies were performed. These include the development of a technique which simulates ion thruster operation without beam extraction, the development of an optical technique to measure ion thruster grid distortion due to thermal expansion, tests of a capacitance measurement technique to quantify the accelerator system grid separation, and the development of a segmented thruster geometry which enables near term development of ion thrusters at power levels greater than 100 kW. Finally, a paper detailing the benefits of electric propulsion for the Space Exploration Initiative was written.

  17. Alternate Propulsion Energy Sources.

    DTIC Science & Technology

    1983-06-01

    Marietta - cryogenic oscillator Dr. Brice Cassenti, UTRC - antimatter propulsion A. E. Mensing, UTRC - nuclear lightbulb engine Michael Fowler, UTRC...sails, laser propulsion, tethers, fusion rockets, antimatter rockets Z9 BSTRACT (Continue on reverse aide if necessary and identify by block number) This...thorough literature search and carry out an intense technical assessment of the latest concepts in science and engineering that show promise of leading to a

  18. Electric propulsion technology

    NASA Technical Reports Server (NTRS)

    Finke, R. C.

    1980-01-01

    The advanced electric propulsion program is directed towards lowering the specific impulse and increasing the thrust per unit of ion thruster systems. In addition, electrothermal and electromagnetic propulsion technologies are being developed to attempt to fill the gap between the conventional ion thruster and chemical rocket systems. Most of these new concepts are exagenous and are represented by rail accelerators, ablative Teflon thrusters, MPD arcs, Free Radicals, etc. Endogenous systems such as metallic hydrogen offer great promise and are also being pursued.

  19. Mission applications of electric propulsion

    NASA Technical Reports Server (NTRS)

    Atkins, K. L.

    1974-01-01

    This paper reviews the mission applications of electric propulsion. The energy requirements of candidate high-energy missions gaining in NASA priority are used to highlight the potential of electric propulsion. Mission-propulsion interfaces are examined to point out differences between chemical and electric applications. Brief comparisons between ballistic requirements and capabilities and those of electric propulsion show that electric propulsion is presently the most practical and perhaps the only technology which can accomplish missions with these energy requirements.

  20. Ion Beam Propulsion Study

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Ion Beam Propulsion Study was a joint high-level study between the Applied Physics Laboratory operated by NASA and ASRC Aerospace at Kennedy Space Center, Florida, and Berkeley Scientific, Berkeley, California. The results were promising and suggested that work should continue if future funding becomes available. The application of ion thrusters for spacecraft propulsion is limited to quite modest ion sources with similarly modest ion beam parameters because of the mass penalty associated with the ion source and its power supply system. Also, the ion source technology has not been able to provide very high-power ion beams. Small ion beam propulsion systems were used with considerable success. Ion propulsion systems brought into practice use an onboard ion source to form an energetic ion beam, typically Xe+ ions, as the propellant. Such systems were used for steering and correction of telecommunication satellites and as the main thruster for the Deep Space 1 demonstration mission. In recent years, "giant" ion sources were developed for the controlled-fusion research effort worldwide, with beam parameters many orders of magnitude greater than the tiny ones of conventional space thruster application. The advent of such huge ion beam sources and the need for advanced propulsion systems for exploration of the solar system suggest a fresh look at ion beam propulsion, now with the giant fusion sources in mind.

  1. Fuel Effective Photonic Propulsion

    NASA Astrophysics Data System (ADS)

    Rajalakshmi, N.; Srivarshini, S.

    2017-09-01

    With the entry of miniaturization in electronics and ultra-small light-weight materials, energy efficient propulsion techniques for space travel can soon be possible. We need to go for such high speeds so that the generation’s time long interstellar missions can be done in incredibly short time. Also renewable energy like sunlight, nuclear energy can be used for propulsion instead of fuel. These propulsion techniques are being worked on currently. The recently proposed photon propulsion concepts are reviewed, that utilize momentum of photons generated by sunlight or onboard photon generators, such as blackbody radiation or lasers, powered by nuclear or solar power. With the understanding of nuclear photonic propulsion, in this paper, a rough estimate of nuclear fuel required to achieve the escape velocity of Earth is done. An overview of the IKAROS space mission for interplanetary travel by JAXA, that was successful in demonstrating that photonic propulsion works and also generated additional solar power on board, is provided; which can be used as a case study. An extension of this idea for interstellar travel, termed as ‘Star Shot’, aims to send a nanocraft to an exoplanet in the nearest star system, which could be potentially habitable. A brief overview of the idea is presented.

  2. Solar Thermal Propulsion Test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Researchers at the Marshall Space Flight Center (MSFC) have designed, fabricated, and tested the first solar thermal engine, a non-chemical rocket engine that produces lower thrust but has better thrust efficiency than a chemical combustion engine. MSFC turned to solar thermal propulsion in the early 1990s due to its simplicity, safety, low cost, and commonality with other propulsion systems. Solar thermal propulsion works by acquiring and redirecting solar energy to heat a propellant. The 20- by 24-ft heliostat mirror (not shown in this photograph) has a dual-axis control that keeps a reflection of the sunlight on the 18-ft diameter concentrator mirror, which then focuses the sunlight to a 4-in focal point inside the vacuum chamber. The focal point has 10 kilowatts of intense solar power. This image, taken during the test, depicts the light being concentrated into the focal point inside the vacuum chamber. As part of MSFC's Space Transportation Directorate, the Propulsion Research Center serves as a national resource for research of advanced, revolutionary propulsion technologies. The mission is to move the Nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft-like access to Earth orbit, rapid travel throughout the solar system, and exploration of interstellar space.

  3. Operationally Efficient Propulsion System Study (OEPSS) data book. Volume 4: OEPSS design concepts

    NASA Technical Reports Server (NTRS)

    Wong, George S.; Ziese, James M.; Farhangi, Shahram

    1990-01-01

    This study was initiated to identify operations problems and cost drivers for current propulsion systems and to identify technology and design approaches to increase the operational efficiency and reduce operations costs for future propulsion systems. To provide readily usable data for the Advanced Launch System (ALS) program, the results of the OEPSS study have been organized into a series of OEPSS Data Books. This volume describes three propulsion concepts that will simplify the propulsion system design and significantly reduce operational requirements. The concepts include: (1) a fully integrated, booster propulsion module concept for the ALS that avoids the complex system created by using autonomous engines with numerous artificial interfaces; (2) an LOX tank aft concept which avoids potentially dangerous geysering in long LOX propellant lines; and (3) an air augmented, rocket engine nozzle afterburning propulsion concept that will significantly reduce LOX propellant requirements, reduce vehicle size and simplify ground operations and ground support equipment and facilities.

  4. Unitized electrolysis propulsion and fuel cell power for selected satellite missions

    SciTech Connect

    McElroy, J.F.; Humble, R.; Groot, W.A. de; Oleson, S.R.; Mitlitsky, R.; Weisberg, A.H.; Myers, B.; Carter, P.H. II

    1998-07-01

    An integrated modular propulsion and regenerative electro-energy storage system for propulsion and power functions on board spacecraft is described. The system is based on electrolysis and fuel cell principles integrated in a single unit. With water as the working fluid for both the power and propulsion systems, a clean, safe, low cost and low weight solution for many spacecraft missions is assured. The system can be designed for stand-alone propulsion, or integrated with the power system. Representative missions for two different size spacecraft are given. Both missions show a significant weight savings when electrolysis propulsion systems are used. The weight savings are augmented when the power system is unified with the propulsion system.

  5. Flight-determined benefits of integrated flight-propulsion control systems

    NASA Technical Reports Server (NTRS)

    Stewart, James F.; Burcham, Frank W., Jr.; Gatlin, Donald H.

    1992-01-01

    Over the last two decades, NASA has conducted several experiments in integrated flight-propulsion control. Benefits have included improved maneuverability; increased thrust, range, and survivability; reduced fuel consumption; and reduced maintenance. This paper presents the basic concepts for control integration, examples of implementation, and benefits. The F-111E experiment integrated the engine and inlet control systems. The YF-12C incorporated an integral control system involving the inlet, autopilot, autothrottle, airdata, navigation, and stability augmentation systems. The F-15 research involved integration of the engine, flight, and inlet control systems. Further extension of the integration included real-time, onboard optimization of engine, inlet, and flight control variables; a self-repairing flight control system; and an engines-only control concept for emergency control. The F-18A aircraft incorporated thrust vectoring integrated with the flight control system to provide enhanced maneuvering at high angles of attack. The flight research programs and the resulting benefits of each program are described.

  6. Experimental Identification and Characterization of Multirotor UAV Propulsion

    NASA Astrophysics Data System (ADS)

    Kotarski, Denis; Krznar, Matija; Piljek, Petar; Simunic, Nikola

    2017-07-01

    In this paper, an experimental procedure for the identification and characterization of multirotor Unmanned Aerial Vehicle (UAV) propulsion is presented. Propulsion configuration needs to be defined precisely in order to achieve required flight performance. Based on the accurate dynamic model and empirical measurements of multirotor propulsion physical parameters, it is possible to design diverse configurations with different characteristics for various purposes. As a case study, we investigated design considerations for a micro indoor multirotor which is suitable for control algorithm implementation in structured environment. It consists of open source autopilot, sensors for indoor flight, “take off the shelf” propulsion components and frame. The series of experiments were conducted to show the process of parameters identification and the procedure for analysis and propulsion characterization. Additionally, we explore battery performance in terms of mass and specific energy. Experimental results show identified and estimated propulsion parameters through which blade element theory is verified.

  7. Individuals with Intellectual disabilities and augmentative and alternative communication: Analysis of survey data on uptake of aided AAC, and loneliness experiences.

    PubMed

    Stancliffe, Roger J; Larson, Sheryl; Auerbach, Karen; Engler, Joshua; Taub, Sarah; Lakin, K Charlie

    2010-06-01

    This study describes uptake of augmentative and alternative communication systems by adults with intellectual disabilities; their ability to self-report at interview; differences in self-reported loneliness experiences by communication mode; and predictors of loneliness. We analyzed National Core Indicators data from 26 US states involving over 13,000 service users grouped by primary means of expression: natural speech, gestures/body language, manual signs, or communication aid/device (aided AAC). Uptake of aided AAC was low; only 0.8% of participants used aided AAC as their primary means of expression. Valid interview responding was higher in turn for participants communicating with natural speech, aided AAC, and other modes. Almost half the participants were lonely, but loneliness did not differ by communication mode used; social contact and social climate variables predicted loneliness. Individuals who used aided AAC communicated more effectively than users of other non-speech modes, supporting more widespread use of aided AAC. Loneliness was prevalent but aided AAC users were not lonelier. Interventions to reduce loneliness are discussed.

  8. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schmidt, George R.; Santarius, John F.; Turchi, Peter J.; Siemon, Richard E.; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    The need for fusion propulsion for interplanetary flights is discussed. For a propulsion system, there are three important system attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For efficient and affordable human exploration of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion obviously cannot meet the requirement in propellant exhaust velocity. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the fission energy to heat a low atomic weight propellant produces propellant velocity of the order of 10 kinds. Alternatively the fission energy can be converted into electricity that is used to accelerate particles to high exhaust velocity. However, the necessary power conversion and conditioning equipment greatly increases the mass of the propulsion system. Fundamental considerations in waste heat rejection and power conditioning in a fission electric propulsion system place a limit on its jet specific power to the order of about 0.2 kW/kg. If fusion can be developed for propulsion, it appears to have the best of all worlds - it can provide the largest absolute amount of energy, the propellant exhaust velocity (> 100 km/s), and the high specific jet power (> 10 kW/kg). An intermediate step towards fusion propulsion might be a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. There are similarities as well as differences between applying fusion to propulsion and to terrestrial electrical power generation. The similarities are the underlying plasma and fusion physics, the enabling component technologies, the computational and the diagnostics capabilities. These physics and

  9. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schmidt, George R.; Santarius, John F.; Turchi, Peter J.; Siemon, Richard E.; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    The need for fusion propulsion for interplanetary flights is discussed. For a propulsion system, there are three important system attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For efficient and affordable human exploration of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion obviously cannot meet the requirement in propellant exhaust velocity. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the fission energy to heat a low atomic weight propellant produces propellant velocity of the order of 10 kinds. Alternatively the fission energy can be converted into electricity that is used to accelerate particles to high exhaust velocity. However, the necessary power conversion and conditioning equipment greatly increases the mass of the propulsion system. Fundamental considerations in waste heat rejection and power conditioning in a fission electric propulsion system place a limit on its jet specific power to the order of about 0.2 kW/kg. If fusion can be developed for propulsion, it appears to have the best of all worlds - it can provide the largest absolute amount of energy, the propellant exhaust velocity (> 100 km/s), and the high specific jet power (> 10 kW/kg). An intermediate step towards fusion propulsion might be a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. There are similarities as well as differences between applying fusion to propulsion and to terrestrial electrical power generation. The similarities are the underlying plasma and fusion physics, the enabling component technologies, the computational and the diagnostics capabilities. These physics and

  10. Megawatt Electromagnetic Plasma Propulsion

    NASA Technical Reports Server (NTRS)

    Gilland, James; Lapointe, Michael; Mikellides, Pavlos

    2003-01-01

    The NASA Glenn Research Center program in megawatt level electric propulsion is centered on electromagnetic acceleration of quasi-neutral plasmas. Specific concepts currently being examined are the Magnetoplasmadynamic (MPD) thruster and the Pulsed Inductive Thruster (PIT). In the case of the MPD thruster, a multifaceted approach of experiments, computational modeling, and systems-level models of self field MPD thrusters is underway. The MPD thruster experimental research consists of a 1-10 MWe, 2 ms pulse-forming-network, a vacuum chamber with two 32 diffusion pumps, and voltage, current, mass flow rate, and thrust stand diagnostics. Current focus is on obtaining repeatable thrust measurements of a Princeton Benchmark type self field thruster operating at 0.5-1 gls of argon. Operation with hydrogen is the ultimate goal to realize the increased efficiency anticipated using the lighter gas. Computational modeling is done using the MACH2 MHD code, which can include real gas effects for propellants of interest to MPD operation. The MACH2 code has been benchmarked against other MPD thruster data, and has been used to create a point design for a 3000 second specific impulse (Isp) MPD thruster. This design is awaiting testing in the experimental facility. For the PIT, a computational investigation using MACH2 has been initiated, with experiments awaiting further funding. Although the calculated results have been found to be sensitive to the initial ionization assumptions, recent results have agreed well with experimental data. Finally, a systems level self-field MPD thruster model has been developed that allows for a mission planner or system designer to input Isp and power level into the model equations and obtain values for efficiency, mass flow rate, and input current and voltage. This model emphasizes algebraic simplicity to allow its incorporation into larger trajectory or system optimization codes. The systems level approach will be extended to the pulsed inductive

  11. Nanosatellite Propulsion Development Program

    NASA Technical Reports Server (NTRS)

    Gagosian, J. S.; Rhee, M. S.; Zakrzwski, C. M.

    1999-01-01

    Earth-orbiting nanosatellite constellations are a unique and exciting means toward fulfilling part of the mission of the Goddard Space Flight Center (GSFC). These constellations, which may consist of several hundred 10-kg spacecraft, present unique challenges in the area of propulsion. Many mission concepts require significant delta-v and attitude control capability to reside in the nanosatellites. In response to requirements from mission feasibility studies, such as the Magnetospheric Constellation study, the GSFC has initiated industry and government partnerships to develop enabling propulsion technologies. The largest challenge has been to meet the power constraints of nanosatellites. These power issues, combined with the high thrust required by many of the missions studied, have led the GSFC to concentrate its efforts on chemical propulsion technology. Electric propulsion technologies capable of performing efficiently at very low power are also of interest to the GSFC as potential candidates for nanosatellite formation flying missions. This paper provides the status of specific industrial or government partnerships undertaken by the GSFC to develop nano/micro propulsion components. Three specific technologies are described in detail: 1) Nanosatellite Solid Rocket Motor Prototype 2) Ultra-Low-Power Cold Gas Thruster for Spin-Axis Precession 3) Micro-Machined Solid-Propellant Gas Generators.

  12. A liquid propulsion panorama

    NASA Astrophysics Data System (ADS)

    Caisso, Philippe; Souchier, Alain; Rothmund, Christophe; Alliot, Patrick; Bonhomme, Christophe; Zinner, Walter; Parsley, Randy; Neill, Todd; Forde, Scott; Starke, Robert; Wang, William; Takahashi, Mamoru; Atsumi, Masahiro; Valentian, Dominique

    2009-12-01

    Liquid-propellant rocket engines are widely used all over the world, thanks to their high performances, in particular high thrust-to-weight ratio. The present paper presents a general panorama of liquid propulsion as a contribution of the IAF Advanced Propulsion Prospective Group. After a brief history of its past development in the different parts of the world, the current status of liquid propulsion, the currently observed trends, the possible areas of future improvement and a summarized road map of future developments are presented. The road map includes a summary of the liquid propulsion status presented in the "Year in review 2007" of Aerospace America. Although liquid propulsion is often seen as a mature technology with few areas of potential improvement, the requirements of an active commercial market and a renewed interest for space exploration has led to the development of a family of new engines, with more design margins, simpler to use and to produce associated with a wide variety of thrust and life requirements.

  13. Nuclear concepts/propulsion

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.

    1993-01-01

    Nuclear thermal and nuclear electric propulsion systems will enable and/or enhance important space exploration missions to the moon and Mars. Current efforts are addressing certain research areas, although NASA and DOE still have much work yet to do. Relative to chemical systems, nuclear thermal propulsion offers the potential of reduced vehicle weight, wider launch windows. and shorter transit times, even without aerobrakes. This would improve crew safety by reducing their exposure to cosmic radiation. Advanced materials and structures will be an important resource in responding to the challenges posed by safety and test facility requirements, environmental concerns, high temperature fuels and the high radiation, hot hydrogen environment within nuclear thermal propulsion systems. Nuclear electric propulsion (NEP) has its own distinct set of advantages relative to chemical systems. These include low resupply mass, the availability of large amounts of onboard electric power for other uses besides propulsion, improved launch windows, and the ability to share technology with surface power systems. Development efforts for NEP reactors will emphasize long life operation of compact designs. This will require designs that provide high fuel burnup and high temperature operation along with personnel and environmental safety.

  14. Pulse-on-bias rocket propulsion concept

    NASA Astrophysics Data System (ADS)

    Vulpetti, Giovanni

    1982-03-01

    An approach to maximise the terminal velocity of a powered spacecraft is investigated through a variable specific impulse programme from two specific-impulse-constant engines. One propulsion system works in a continuous mode. The other one does in a pulsed mode. The variable jet speed is obtained by allowing the time between two consecutive pulses to vary. Modeling the "bias" and pulsed engines together with S/C significant systems a nonlinear programming problem is stated. Propellant and P/L, effective power and propulsion time are fixed. Specialising the problem to a NEP S/C for distant targets in the solar system a comparison is made with same flights for which the S/C uses one propulsion system. There exist ranges of initial mass and propellant fraction where the final ship velocity augments considerably in the pulse-on-bias policy, especially at lower power levels. In such environments, a meaningful example is a gain of three targets—from Saturn to Pluto—for a 5-ton 150-kWe 75-day 32%-fuel acceleration flight.

  15. The NASA-JPL advanced propulsion program

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    1994-01-01

    The NASA Advanced Propulsion Concepts (APC) program at the Jet Propulsion Laboratory (JPL) consists of two main areas: The first involves cooperative modeling and research activities between JPL and various universities and industry; the second involves research at universities and industry that is directly supported by JPL. The cooperative research program consists of mission studies, research and development of ion engine technology using C-60 (Buckminsterfullerene) propellant, and research and development of lithium-propellant Lorentz-force accelerator (LFA) engine technology. The university/industry- supported research includes research (modeling and proof-of-concept experiments) in advanced, long-life electric propulsion, and in fusion propulsion. These propulsion concepts were selected primarily to cover a range of applications from near-term to far-term missions. For example, the long-lived pulsed-xenon thruster research that JPL is supporting at Princeton University addresses the near-term need for efficient, long-life attitude control and station-keeping propulsion for Earth-orbiting spacecraft. The C-60-propellant ion engine has the potential for good efficiency in a relatively low specific impulse (Isp) range (10,000 - 30,000 m/s) that is optimum for relatively fast (less than 100 day) cis-lunar (LEO/GEO/Lunar) missions employing near-term, high-specific mass electric propulsion vehicles. Research and modeling on the C-60-ion engine are currently being performed by JPL (engine demonstration), Caltech (C-60 properties), MIT (plume modeling), and USC (diagnostics). The Li-propellant LFA engine also has good efficiency in the modest Isp range (40,000 - 50,000 m/s) that is optimum for near-to-mid-term megawatt-class solar- and nuclear-electric propulsion vehicles used for Mars missions transporting cargo (in support of a piloted mission). Research and modeling on the Li-LFA engine are currently being performed by JPL (cathode development), Moscow Aviation

  16. The F-15B Propulsion Flight Test Fixture: A New Flight Facility For Propulsion Research

    NASA Technical Reports Server (NTRS)

    Corda, Stephen; Vachon, M. Jake; Palumbo, Nathan; Diebler, Corey; Tseng, Ting; Ginn, Anthony; Richwine, David

    2001-01-01

    The design and development of the F-15B Propulsion Flight Test Fixture (PFTF), a new facility for propulsion flight research, is described. Mounted underneath an F-15B fuselage, the PFTF provides volume for experiment systems and attachment points for propulsion devices. A unique feature of the PFTF is the incorporation of a six-degree-of-freedom force balance. Three-axis forces and moments can be measured in flight for experiments mounted to the force balance. The NASA F-15B airplane is described, including its performance and capabilities as a research test bed aircraft. The detailed description of the PFTF includes the geometry, internal layout and volume, force-balance operation, available instrumentation, and allowable experiment size and weight. The aerodynamic, stability and control, and structural designs of the PFTF are discussed, including results from aerodynamic computational fluid dynamic calculations and structural analyses. Details of current and future propulsion flight experiments are discussed. Information about the integration of propulsion flight experiments is provided for the potential PFTF user.

  17. Preliminary Assessment of Using Gelled and Hybrid Propellant Propulsion for VTOL/SSTO Launch Systems

    NASA Technical Reports Server (NTRS)

    Palaszewski, Bryan; OLeary, Robert; Pelaccio, Dennis G.

    1998-01-01

    A novel, reusable, Vertical-Takeoff-and-Vertical-Takeoff-and-Landing, Single-Stage-to-Orbit (VTOL/SSTO) launch system concept, named AUGMENT-SSTO, is presented in this paper to help quantify the advantages of employing gelled and hybrid propellant propulsion system options for such applications. The launch vehicle system concept considered uses a highly coupled, main high performance liquid oxygen/liquid hydrogen (LO2/LH2) propulsion system, that is used only for launch, while a gelled or hybrid propellant propulsion system auxiliary propulsion system is used during final orbit insertion, major orbit maneuvering, and landing propulsive burn phases of flight. Using a gelled or hybrid propellant propulsion system for major orbit maneuver burns and landing has many advantages over conventional VTOL/SSTO concepts that use LO2/LH2 propulsion system(s) burns for all phases of flight. The applicability of three gelled propellant systems, O2/H2/Al, O2/RP-1/Al, and NTO/MMH/Al, and a state-of-the-art (SOA) hybrid propulsion system are examined in this study. Additionally, this paper addresses the applicability of a high performance gelled O2/H2 propulsion system to perform the primary, as well as the auxiliary propulsion system functions of the vehicle.

  18. X-37 Storable Propulsion System Design and Operations

    NASA Technical Reports Server (NTRS)

    Rodriguez, Henry; Popp, Chris; Rehagen, Ronald J.

    2005-01-01

    In a response to NASA's X-37 TA-10 Cycle-1 contract, Boeing assessed nitrogen tetroxide (N2O4) and monomethyl hydrazine (MMH) Storable Propellant Propulsion Systems to select a low risk X-37 propulsion development approach. Space Shuttle lessons learned, planetary spacecraft, and Boeing Satellite HS-601 systems were reviewed to arrive at a low risk and reliable storable propulsion system. This paper describes the requirements, trade studies, design solutions, flight and ground operational issues which drove X-37 toward the selection of a storable propulsion system. The design of storable propulsion systems offers the leveraging of hardware experience that can accelerate progress toward critical design. It also involves the experience gained from launching systems using MMH and N2O4 propellants. Leveraging of previously flight-qualified hardware may offer economic benefits and may reduce risk in cost and schedule. This paper summarizes recommendations based on experience gained from Space Shuttle and similar propulsion systems utilizing MMH and N2O4 propellants. System design insights gained from flying storable propulsion are presented and addressed in the context of the design approach of the X-37 propulsion system.

  19. X-37 Storable Propulsion System Design and Operations

    NASA Technical Reports Server (NTRS)

    Rodriguez, Henry; Popp, Chris; Rehegan, Ronald J.

    2006-01-01

    In a response to NASA's X-37 TA-10 Cycle-1 contract, Boeing assessed nitrogen tetroxide (N2O4) and monomethyl hydrazine (MMH) Storable Propellant Propulsion Systems to select a low risk X-37 propulsion development approach. Space Shuttle lessons learned, planetary spacecraft, and Boeing Satellite HS-601 systems were reviewed to arrive at a low risk and reliable storable propulsion system. This paper describes the requirements, trade studies, design solutions, flight and ground operational issues which drove X-37 toward the selection of a storable propulsion system. The design of storable propulsion systems offers the leveraging of hardware experience that can accelerate progress toward critical design. It also involves the experience gained from launching systems using MMH and N2O4 propellants. Leveraging of previously flight-qualified hardware may offer economic benefits and may reduce risk in cost and schedule. This paper summarizes recommendations based on experience gained from Space Shuttle and similar propulsion systems utilizing MMH and N2O4 propellants. System design insights gained from flying storable propulsion are presented and addressed in the context of the design approach of the X-37 propulsion system.

  20. Free radical propulsion concept

    NASA Technical Reports Server (NTRS)

    Hawkins, C. E.; Nakanishi, S.

    1981-01-01

    A free radical propulsion concept utilizing the recombination energy of dissociated low molecular weight gases to produce thrust was examined. The concept offered promise of a propulsion system operating at a theoretical impulse, with hydrogen, as high as 2200 seconds at high thrust to power ratio, thus filling the gas existing between chemical and electrostatic propulsion capabilities. Microwave energy used to dissociate a continuously flowing gas was transferred to the propellant via three body recombination for conversion to propellant kinetic energy. Power absorption by the microwave plasma discharge was in excess of 90 percent over a broad range of pressures. Gas temperatures inferred from gas dynamic equations showed much higher temperatures from microwave heating than from electrothermal heating. Spectroscopic analysis appeared to corroborate the inferred temperatures of one of the gases tested.

  1. Advanced rocket propulsion

    NASA Technical Reports Server (NTRS)

    Obrien, Charles J.

    1993-01-01

    Existing NASA research contracts are supporting development of advanced reinforced polymer and metal matrix composites for use in liquid rocket engines of the future. Advanced rocket propulsion concepts, such as modular platelet engines, dual-fuel dual-expander engines, and variable mixture ratio engines, require advanced materials and structures to reduce overall vehicle weight as well as address specific propulsion system problems related to elevated operating temperatures, new engine components, and unique operating processes. High performance propulsion systems with improved manufacturability and maintainability are needed for single stage to orbit vehicles and other high performance mission applications. One way to satisfy these needs is to develop a small engine which can be clustered in modules to provide required levels of total thrust. This approach should reduce development schedule and cost requirements by lowering hardware lead times and permitting the use of existing test facilities. Modular engines should also reduce operational costs associated with maintenance and parts inventories.

  2. Nuclear electric propulsion

    NASA Technical Reports Server (NTRS)

    Keaton, Paul W.; Tubb, David J.

    1986-01-01

    The feasibility is investigated of using nuclear electric propulsion (NEP) for slow freighter ships traveling from a 500 km low Earth orbit (LEO) to the Moon's orbit about the Earth, and on to Mars. NEP is also shown to be feasible for transporting people to Mars on long conjunction-class missions lasting about nine months one way, and on short sprint missions lasting four months one way. Generally, it was not attempted to optimize ion exhaust velocities, but rather suitable parameters to demonstrate NEP feasibility were chosen. Various combinations of missions are compared with chemical and nuclear thermal propulsion (NTR) systems. Typically, NEP and NTR can accomplish the same lifting task with similar mass in LEO. When compared to chemical propulsion, NEP was found to accomplish the same missions with 40% less mass in LEO. These findings are sufficiently encouraging as to merit further studies with optimum systems.

  3. Space station propulsion technology

    NASA Technical Reports Server (NTRS)

    Briley, G. L.

    1986-01-01

    The progress on the Space Station Propulsion Technology Program is described. The objectives are to provide a demonstration of hydrogen/oxygen propulsion technology readiness for the Initial Operating Capability (IOC) space station application, specifically gaseous hydrogen/oxygen and warm hydrogen thruster concepts, and to establish a means for evolving from the IOC space station propulsion to that required to support and interface with advanced station functions. The evaluation of concepts was completed. The accumulator module of the test bed was completed and, with the microprocessor controller, delivered to NASA-MSFC. An oxygen/hydrogen thruster was modified for use with the test bed and successfully tested at mixture ratios from 4:1 to 8:1.

  4. Advanced Chemical Propulsion Study

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon; Byers, Dave; Alexander, Leslie A.; Krebsbach, Al

    2004-01-01

    A study was performed of advanced chemical propulsion technology application to space science (Code S) missions. The purpose was to begin the process of selecting chemical propulsion technology advancement activities that would provide greatest benefits to Code S missions. Several missions were selected from Code S planning data, and a range of advanced chemical propulsion options was analyzed to assess capabilities and benefits re these missions. Selected beneficial applications were found for higher-performing bipropellants, gelled propellants, and cryogenic propellants. Technology advancement recommendations included cryocoolers and small turbopump engines for cryogenic propellants; space storable propellants such as LOX-hydrazine; and advanced monopropellants. It was noted that fluorine-bearing oxidizers offer performance gains over more benign oxidizers. Potential benefits were observed for gelled propellants that could be allowed to freeze, then thawed for use.

  5. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

    2001-01-01

    There is little doubt that humans will attempt to explore and develop the solar system in this century. A large amount of energy will be required for accomplishing this. The need for fusion propulsion is discussed. For a propulsion system, there are three important thermodynamical attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For human exploration and development of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion can produce exhaust velocity up to about 5 km/s. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the energy to heat a hydrogen propellant increases the exhaust velocity by only a factor of about two. Alternatively the energy can be converted into electricity which is then used to accelerate particles to high exhaust velocity. The necessary power conversion and conditioning equipment, however, increases the mass of the propulsion system for the same jet power by more than two orders of magnitude over chemical system, thus greatly limits the thrust-to-weight ratio attainable. The principal advantage of the fission process is that its development is relatively mature and is available right now. If fusion can be developed, fusion appears to have the best of all worlds in terms of propulsion - it can provide the absolute amount, the propellant exhaust velocity, and the high specific jet power. An intermediate step towards pure fusion propulsion is a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. The technical issues related to fusion for space propulsion are discussed. The technical priorities for developing and applying fusion for propulsion are

  6. Jet propulsion for airplanes

    NASA Technical Reports Server (NTRS)

    Buckingham, Edgar

    1924-01-01

    This report is a description of a method of propelling airplanes by the reaction of jet propulsion. Air is compressed and mixed with fuel in a combustion chamber, where the mixture burns at constant pressure. The combustion products issue through a nozzle, and the reaction of that of the motor-driven air screw. The computations are outlined and the results given by tables and curves. The relative fuel consumption and weight of machinery for the jet, decrease as the flying speed increases; but at 250 miles per hour the jet would still take about four times as much fuel per thrust horsepower-hour as the air screw, and the power plant would be heavier and much more complicated. Propulsion by the reaction of a simple jet can not compete with air screw propulsion at such flying speeds as are now in prospect.

  7. Electric Propulsion Applications and Impacts

    NASA Technical Reports Server (NTRS)

    Curran, Frank M.; Wickenheiser, Timothy J.

    1996-01-01

    Most space missions require on-board propulsion systems and these systems are often dominant spacecraft mass drivers. Presently, on-board systems account for more than half the injected mass for commercial communications systems and even greater mass fractions for ambitious planetary missions. Anticipated trends toward the use of both smaller spacecraft and launch vehicles will likely increase pressure on the performance of on-board propulsion systems. The acceptance of arcjet thrusters for operational use on commercial communications satellites ushered in a new era in on-board propulsion and exponential growth of electric propulsion across a broad spectrum of missions is anticipated. NASA recognizes the benefits of advanced propulsion and NASA's Office of Space Access and Technology supports an aggressive On-Board Propulsion program, including a strong electric propulsion element, to assure the availability of high performance propulsion systems to meet the goals of the ambitious missions envisioned in the next two decades. The program scope ranges from fundamental research for future generation systems through specific insertion efforts aimed at near term technology transfer. The On-Board propulsion program is committed to carrying technologies to levels required for customer acceptance and emphasizes direct interactions with the user community and the development of commercial sources. This paper provides a discussion of anticipated missions, propulsion functions, and electric propulsion impacts followed by an overview of the electric propulsion element of the NASA On-Board Propulsion program.

  8. Space Transportation Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Liou, Meng-Sing; Stewart, Mark E.; Suresh, Ambady; Owen, A. Karl

    2001-01-01

    This report outlines the Space Transportation Propulsion Systems for the NPSS (Numerical Propulsion System Simulation) program. Topics include: 1) a review of Engine/Inlet Coupling Work; 2) Background/Organization of Space Transportation Initiative; 3) Synergy between High Performance Computing and Communications Program (HPCCP) and Advanced Space Transportation Program (ASTP); 4) Status of Space Transportation Effort, including planned deliverables for FY01-FY06, FY00 accomplishments (HPCCP Funded) and FY01 Major Milestones (HPCCP and ASTP); and 5) a review current technical efforts, including a review of the Rocket-Based Combined-Cycle (RBCC), Scope of Work, RBCC Concept Aerodynamic Analysis and RBCC Concept Multidisciplinary Analysis.

  9. Pulsed Laser Propulsion.

    DTIC Science & Technology

    1978-10-01

    afforded by a pulsed laser propulsion system over a CW laser propulsion system are 1) simplicity in engine design as a result of permitting the laser...to engineering and weight considerations. The lower boundary of the corridor is set by propellant feed considerations. To the right of this boundary...example, a OOJ -5 per pulse laser operating at 7 x 10 sec between pulses (14, 285 pps) is capable of powering a 30 lb (135 Nt)thrust rocket engine that has

  10. Supersonic laser propulsion.

    PubMed

    Rezunkov, Yurii; Schmidt, Alexander

    2014-11-01

    To produce supersonic laser propulsion, a new technique based on the interaction of a laser-ablated jet with supersonic gas flow in a nozzle is proposed. It is shown that such parameters of the jet, such as gas-plasma pressure and temperature in the ablation region as well as the mass consumption rate of the ablated solid propellant, are characteristic in this respect. The results of numerical simulations of the supersonic laser propulsion are presented for two types of nozzle configuration. The feasibility to achieve the momentum coupling coefficient of C(m)∼10(-3) N/W is shown.

  11. Propulsion controlled aircraft computer

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  12. Satellite/spacecraft propulsion

    NASA Technical Reports Server (NTRS)

    Dowdy, Mack W.

    1991-01-01

    Propulsion system performance has high leverage for many future missions because of large propellant mass requirements. Relatively small performance improvements can translate into large increases in payload and science return. Contamination control becomes more important as science instruments become more sensitive. This places more emphasis on exhaust plume contamination control. The need for reliable operation and long life places increased importance on health monitoring and control of spacecraft propulsion systems. The need for accurate spacecraft pointing and control increases the need for small impulse-bit thrusters. This presentation is represented by viewgraphs.

  13. Focused technology: Nuclear propulsion

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.

    1991-01-01

    The topics presented are covered in viewgraph form and include: nuclear thermal propulsion (NTP), which challenges (1) high temperature fuel and materials, (2) hot hydrogen environment, (3) test facilities, (4) safety, (5) environmental impact compliance, and (6) concept development, and nuclear electric propulsion (NEP), which challenges (1) long operational lifetime, (2) high temperature reactors, turbines, and radiators, (3) high fuel burn-up reactor fuels, and designs, (4) efficient, high temperature power conditioning, (5) high efficiency, and long life thrusters, (6) safety, (7) environmental impact compliance, and (8) concept development.

  14. An antiproton driver for ICF propulsion

    NASA Technical Reports Server (NTRS)

    Chiang, Pi-Ren; Lewis, R. A.; Smith, G. A.; Gazze, C.; Higman, K.; Newton, R.; Chiaverini, M.; Dailey, J.; Surratt, M.; Werthman, W. Lance

    1993-01-01

    Inertial confinement fusion (ICF) utilizing an anitprotoncatalyzed target is discussed as a possible source of propulsion for rapid interplanetary manned space missions. The relevant compression, ignition, and thrust mechanisms are presented. Progress on an experiment presently in progress at the Phillips Laboratory, Kirtland AFB, NM to demonstrate proof-of-principle is reviewed.

  15. Trapping antimatter for space propulsion applications

    SciTech Connect

    Goebel, W.A.; Holzscheiter, M.H.; Lewis, R.A.; Rochet, J.; Schwartz, W.L.; Smith, G.A.

    1996-03-01

    Production and trapping of antiprotons for space propulsion applications are reviewed. Present and foreseeable production rates at Fermilab are discussed, and experiments on trapping, confinement and transport of large quantities of antiprotons are outlined. {copyright} {ital 1996 American Institute of Physics.}

  16. Space transportation propulsion USSR launcher technology, 1990

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Space transportation propulsion U.S.S.R. launcher technology is discussed. The following subject areas are covered: Energia background (launch vehicle summary, Soviet launcher family) and Energia propulsion characteristics (booster propulsion, core propulsion, and growth capability).

  17. Propulsion mechanisms for Leidenfrost solids on ratchets.

    PubMed

    Baier, Tobias; Dupeux, Guillaume; Herbert, Stefan; Hardt, Steffen; Quéré, David

    2013-02-01

    We propose a model for the propulsion of Leidenfrost solids on ratchets based on viscous drag due to the flow of evaporating vapor. The model assumes pressure-driven flow described by the Navier-Stokes equations and is mainly studied in lubrication approximation. A scaling expression is derived for the dependence of the propulsive force on geometric parameters of the ratchet surface and properties of the sublimating solid. We show that the model results as well as the scaling law compare favorably with experiments and are able to reproduce the experimentally observed scaling with the size of the solid.

  18. Advanced Propulsion Physics Lab: Eagleworks Investigations

    NASA Technical Reports Server (NTRS)

    Scogin, Tyler

    2014-01-01

    Eagleworks Laboratory is an advanced propulsions physics laboratory with two primary investigations currently underway. The first is a Quantum Vacuum Plasma Thruster (QVPT or Q-thrusters), an advanced electric propulsion technology in the development and demonstration phase. The second investigation is in Warp Field Interferometry (WFI). This is an investigation of Dr. Harold "Sonny" White's theoretical physics models for warp field equations using optical experiments in the Electro Optical laboratory (EOL) at Johnson Space Center. These investigations are pursuing technology necessary to enable human exploration of the solar system and beyond.

  19. Actin-based propulsion of a microswimmer.

    PubMed

    Leshansky, A M

    2006-07-01

    A simple hydrodynamic model of actin-based propulsion of microparticles in dilute cell-free cytoplasmic extracts is presented. Under the basic assumption that actin polymerization at the particle surface acts as a force dipole, pushing apart the load and the free (nonanchored) actin tail, the propulsive velocity of the microparticle is determined as a function of the tail length, porosity, and particle shape. The anticipated velocities of the cargo displacement and the rearward motion of the tail are in good agreement with recently reported results of biomimetic experiments. A more detailed analysis of the particle-tail hydrodynamic interaction is presented and compared to the prediction of the simplified model.

  20. Propulsion and Power Using Electrodynamics

    NASA Astrophysics Data System (ADS)

    Johnson, L.; Krause, L. H.; Wiegmann, B.; Bilen, S.; Gilchrist, B.

    2017-02-01

    Electrodynamic tethers provide propulsion and power by interacting with planetary magnetospheres, enabling propulsive-intense maneuvers and high-power without fuel or radioisotope power. Electric sails can propel spacecraft throughout the solar system.

  1. Nuclear thermal propulsion program overview

    NASA Technical Reports Server (NTRS)

    Bennett, Gary L.

    1991-01-01

    Nuclear thermal propulsion program is described. The following subject areas are covered: lunar and Mars missions; national space policy; international cooperation in space exploration; propulsion technology; nuclear rocket program; and budgeting.

  2. Emerging Physics for Novel Field Propulsion Science

    NASA Astrophysics Data System (ADS)

    Hauser, Jochem; Dröscher, Walter

    2010-01-01

    All space vehicles in use today need some kind of fuel for operation. The basic physics underlying this propulsion principle severely limits the specific impulse and/or available thrust. Launch capabilities from the surface of the Earth require huge amounts of fuel. Hence, space flight, as envisaged by von Braun in the early 50s of the last century, will not be possible using this concept. Only if novel physical principles are found can these limits be overcome. Gravitational field propulsion is based on the generation of gravitational (gravity-like) fields by manmade devices. In other words, gravity-like fields should be experimentally controllable. Present physics believes that there are four fundamental interactions: strong (nuclei), weak (radioactive decay), electromagnetism and Newtonian gravitation. As experience has shown for the last six decades, none of these physical interactions is suitable as a basis for novel space propulsion. None of the advanced physical theories like string theory or quantum gravity, go beyond these four known interactions. On the contrary, recent results from causal dynamical triangulation simulations indicate that wormholes in spacetime do not seem to exist, and thus even this type of exotic space travel may well be impossible. Recently, novel physical concepts were published that might lead to advanced space propulsion technology, represented by two additional long range gravitational-like force fields that would be both attractive and repulsive, resulting from interaction of gravity with electromagnetism. A propulsion technology, based on these novel long range fields, would be working without propellant.

  3. Xenon ion propulsion for orbit transfer

    NASA Technical Reports Server (NTRS)

    Rawlin, V. K.; Patterson, M. J.; Gruber, R. P.

    1990-01-01

    The status of critical ion propulsion system elements is reviewed. Electron bombardment ion thrusters for primary propulsion have evolved to operate on xenon in the 5-10 kW power range. Thruster efficiencies of 0.7 and specific impulse values of 4000 s have been documented. The baseline thruster currently under development by NASA LeRC includes ring-cusp magnetic field plasma containment and dished two-grid ion optics. Based on past experience and demonstrated simplifications, power processors for these thrusters should have approximately 500 parts, a mass of 40 kg, and an efficiency near 0.94. Thrust vector control, via individual thruster gimbals, is a mature technology. High pressure, gaseous xenon propellant storage and control schemes, using flight qualified hardware, result in propellant tankage fractions between 0.1 and 0.2. In-space and ground integration testing has demonstrated that ion propulsion systems can be successfully integrated with their host spacecraft.

  4. NASA Breakthrough Propulsion Physics Workshop Proceedings

    NASA Technical Reports Server (NTRS)

    Millis, Marc G. (Editor); Williamson, Gary Scott (Editor)

    1999-01-01

    In August 1997, NASA sponsored a 3-day workshop to assess the prospects emerging from physics that may eventually lead to creating propulsion breakthroughs -the kind of breakthroughs that could revolutionize space flight and enable human voyages to other star systems. Experiments and theories were discussed regarding the coupling of gravity and electromagnetism, vacuum fluctuation energy, warp drives and wormholes, and superluminal quantum tunneling. Because the propulsion goals are presumably far from fruition, a special emphasis was to identify affordable, near-term, and credible research tasks that could make measurable progress toward these grand ambitions. This workshop was one of the first steps for the new NASA Breakthrough Propulsion Physics program led by the NASA Lewis Research Center.

  5. NASA Electric Propulsion System Studies

    NASA Technical Reports Server (NTRS)

    Felder, James L.

    2015-01-01

    An overview of NASA efforts in the area of hybrid electric and turboelectric propulsion in large transport. This overview includes a list of reasons why we are looking at transmitting some or all of the propulsive power for the aircraft electrically, a list of the different types of hybrid-turbo electric propulsion systems, and the results of 4 aircraft studies that examined different types of hybrid-turbo electric propulsion systems.

  6. Orbital Analysis of Macron Propulsion

    DTIC Science & Technology

    2010-07-28

    storage and solid-state switching enabled the use of peristaltic, pulsed inductive acceleration of non- ferritic particles for spacecraft propulsion...switching enabled the use of peristaltic, pulsed inductive acceleration of non- ferritic particles for spacecraft propulsion. Macron Launched Propulsion (MLP...peristaltic, pulsed inductive acceleration techniques of non- ferritic particles to electromagnetically accelerate macrons (i.e. a macroscopic particle with an

  7. SPE propulsion electrolyzer for NASA's integrated propulsion test article

    NASA Astrophysics Data System (ADS)

    1991-08-01

    Hamilton Standard has delivered a 3000 PSI SPE Propulsion Electrolyzer Stack and Special Test Fixture to the NASA Lyndon B. Johnson Space Center (JSC) Integrated Propulsion Test Article (IPTA) program in June 1990, per contract NAS9-18030. This prototype unit demonstrates the feasibility of SPE-high pressure water electrolysis for future space applications such as Space Station propulsion and Lunar/Mars energy storage. The SPE-Propulsion Electrolyzer has met or exceeded all IPTA program goals. It continues to function as the primary hydrogen and oxygen source for the IPTA test bed at the NASA/JSC Propulsion and Power Division Thermochemical Test Branch.

  8. SPE propulsion electrolyzer for NASA's integrated propulsion test article

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Hamilton Standard has delivered a 3000 PSI SPE Propulsion Electrolyzer Stack and Special Test Fixture to the NASA Lyndon B. Johnson Space Center (JSC) Integrated Propulsion Test Article (IPTA) program in June 1990, per contract NAS9-18030. This prototype unit demonstrates the feasibility of SPE-high pressure water electrolysis for future space applications such as Space Station propulsion and Lunar/Mars energy storage. The SPE-Propulsion Electrolyzer has met or exceeded all IPTA program goals. It continues to function as the primary hydrogen and oxygen source for the IPTA test bed at the NASA/JSC Propulsion and Power Division Thermochemical Test Branch.

  9. Mirror fusion propulsion system - A performance comparison with alternate propulsion systems for the manned Mars mission

    NASA Technical Reports Server (NTRS)

    Deveny, M.; Carpenter, S.; O'Connell, T.; Schulze, N.

    1993-01-01

    The performance characteristics of several propulsion technologies applied to piloted Mars missions are compared. The characteristics that are compared are Initial Mass in Low Earth Orbit (IMLEO), mission flexibility, and flight times. The propulsion systems being compared are both demonstrated and envisioned: Chemical (or Cryogenic), Nuclear Thermal Rocket (NTR) solid core, NTR gas core, Nuclear Electric Propulsion (NEP), and a mirror fusion space propulsion system. The proposed magnetic mirror fusion reactor, known as the Mirror Fusion Propulsion System (MFPS), is described. The description is an overview of a design study that was conducted to convert a mirror reactor experiment at Lawrence Livermore National Lab (LLNL) into a viable space propulsion system. Design principles geared towards minimizing mass and maximizing power available for thrust are identified and applied to the LLNL reactor design, resulting in the MFPS. The MFPS' design evolution, reactor and fuel choices, and system configuration are described. Results of the performance comparison shows that the MFPS minimizes flight time to 60 to 90 days for flights to Mars while allowing continuous return-home capability while at Mars. Total MFPS IMLEO including propellant and payloads is kept to about 1,000 metric tons.

  10. Mirror fusion propulsion system: A performance comparison with alternate propulsion systems for the manned Mars Mission

    NASA Technical Reports Server (NTRS)

    Schulze, Norman R.; Carpenter, Scott A.; Deveny, Marc E.; Oconnell, T.

    1993-01-01

    The performance characteristics of several propulsion technologies applied to piloted Mars missions are compared. The characteristics that are compared are Initial Mass in Low Earth Orbit (IMLEO), mission flexibility, and flight times. The propulsion systems being compared are both demonstrated and envisioned: Chemical (or Cryogenic), Nuclear Thermal Rocket (NTR) solid core, NTR gas core, Nuclear Electric Propulsion (NEP), and a mirror fusion space propulsion system. The proposed magnetic mirror fusion reactor, known as the Mirror Fusion Propulsion System (MFPS), is described. The description is an overview of a design study that was conducted to convert a mirror reactor experiment at Lawrence Livermore National Lab (LLNL) into a viable space propulsion system. Design principles geared towards minimizing mass and maximizing power available for thrust are identified and applied to the LLNL reactor design, resulting in the MFPS. The MFPS' design evolution, reactor and fuel choices, and system configuration are described. Results of the performance comparison shows that the MFPS minimizes flight time to 60 to 90 days for flights to Mars while allowing continuous return-home capability while at Mars. Total MFPS IMLEO including propellant and payloads is kept to about 1,000 metric tons.

  11. Mirror fusion propulsion system - A performance comparison with alternate propulsion systems for the manned Mars mission

    NASA Technical Reports Server (NTRS)

    Deveny, M.; Carpenter, S.; O'Connell, T.; Schulze, N.

    1993-01-01

    The performance characteristics of several propulsion technologies applied to piloted Mars missions are compared. The characteristics that are compared are Initial Mass in Low Earth Orbit (IMLEO), mission flexibility, and flight times. The propulsion systems being compared are both demonstrated and envisioned: Chemical (or Cryogenic), Nuclear Thermal Rocket (NTR) solid core, NTR gas core, Nuclear Electric Propulsion (NEP), and a mirror fusion space propulsion system. The proposed magnetic mirror fusion reactor, known as the Mirror Fusion Propulsion System (MFPS), is described. The description is an overview of a design study that was conducted to convert a mirror reactor experiment at Lawrence Livermore National Lab (LLNL) into a viable space propulsion system. Design principles geared towards minimizing mass and maximizing power available for thrust are identified and applied to the LLNL reactor design, resulting in the MFPS. The MFPS' design evolution, reactor and fuel choices, and system configuration are described. Results of the performance comparison shows that the MFPS minimizes flight time to 60 to 90 days for flights to Mars while allowing continuous return-home capability while at Mars. Total MFPS IMLEO including propellant and payloads is kept to about 1,000 metric tons.

  12. Solar Electric Propulsion

    NASA Technical Reports Server (NTRS)

    LaPointe, Michael

    2006-01-01

    The Solar Electric Propulsion (SEP) technology area is tasked to develop near and mid-term SEP technology to improve or enable science mission capture while minimizing risk and cost to the end user. The solar electric propulsion investments are primarily driven by SMD cost-capped mission needs. The technology needs are determined partially through systems analysis tasks including the recent "Re-focus Studies" and "Standard Architecture Study." These systems analysis tasks transitioned the technology development to address the near term propulsion needs suitable for cost-capped open solicited missions such as Discovery and New Frontiers Class missions. Major SEP activities include NASA's Evolutionary Xenon Thruster (NEXT), implementing a Standard Architecture for NSTAR and NEXT EP systems, and developing a long life High Voltage Hall Accelerator (HiVHAC). Lower level investments include advanced feed system development and xenon recovery testing. Future plans include completion of ongoing ISP development activities and evaluating potential use of commercial electric propulsion systems for SMD applications. Examples of enhanced mission capability and technology readiness dates shall be discussed.

  13. Turboprop Propulsion Mechanic.

    ERIC Educational Resources Information Center

    Chanute AFB Technical Training Center, IL.

    This instructional package consists of a plan of instruction, glossary, and student handouts and exercises for use in training Air Force personnel to become turboprop propulsion mechanics. Addressed in the individual lessons of the course are the following: common hand tools, hardware, measuring devices, and safety wiring; aircraft and engine…

  14. Rarefaction wave gun propulsion

    NASA Astrophysics Data System (ADS)

    Kathe, Eric Lee

    A new species of gun propulsion that dramatically reduces recoil momentum imparted to the gun is presented. First conceived by the author on 18 March 1999, the propulsion concept is explained, a methodology for the design of a reasonable apparatus for experimental validation using NATO standard 35mm TP anti-aircraft ammunition is developed, and the experimental results are presented. The firing results are juxtaposed by a simple interior ballistic model to place the experimental findings into a context within which they may better be understood. Rarefaction wave gun (RAVEN) propulsion is an original contribution to the field of armament engineering. No precedent is known, and no experimental results of such a gun have been published until now. Recoil reduction in excess of 50% was experimentally achieved without measured loss in projectile velocity. RAVEN achieves recoil reduction by means of a delayed venting of the breech of the gun chamber that directs the high enthalpy propellant gases through an expansion nozzle to generate forward thrust that abates the rearward momentum applied to the gun prior to venting. The novel feature of RAVEN, relative to prior recoilless rifles, is that sufficiently delayed venting results in a rarefaction wave that follows the projectile though the bore without catching it. Thus, the projectile exits the muzzle without any compromise to its propulsion performance relative to guns that maintain a sealed chamber.

  15. General Aviation Propulsion

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Programs exploring and demonstrating new technologies in general aviation propulsion are considered. These programs are the quiet, clean, general aviation turbofan (QCGAT) program; the general aviation turbine engine (GATE) study program; the general aviation propeller technology program; and the advanced rotary, diesel, and reciprocating engine programs.

  16. NASA Now: Propulsion

    NASA Image and Video Library

    In this episode of NASA Now, you’ll visit NASA’s Spacecraft Propulsion Research Facility, called B-2, at NASA Plum Brook Station. You’ll meet Dr. Louis Povinelli and Brian Jones who explain w...

  17. Dynamics of intestinal propulsion.

    PubMed

    Miftahof, R; Akhmadeev, N

    2007-05-21

    A biomechanical model and mathematical formulation of the problem of propulsion of a solid non-deformable pellet by an isolated segment of the gut are presented. The organ is modeled as a soft orthotropic cylindrical biological shell. Its wall is reinforced by transversely isotropic muscle fibers of orthogonal type of weaving embedded in a connective tissue stroma. The mechanical properties of the wall are assumed to be nonlinear, deformations are finite. The longitudinal smooth muscle syncitium possesses anisotropic and the circular muscle syncytium has anisotropic electrical properties. Their electromechanical activity is under control of a pacemaker, which is represented by interstitial cells of Cajal. The model describes the dynamics of the generation and propagation of mechanical waves of contraction-relaxation along the surface of the bioshell and propulsion of the pellet. The governing system of equations was solved numerically. The combined finite-difference and finite-element method was used. The results demonstrate that pendular movements alone provide an aboral transit, without mixing though, of the bolus. Non-propagating segmental contractions show small amplitude librations of the pellet without its visible propulsion. Only the coordinated activity of both smooth muscle layers in a form of the peristaltic reflex provides physiologically significant simultaneous propulsion and mixing of the intraluminal content (pellet).

  18. H2OTSTUF: Appropriate Operating Regimes for Magnetohydrodynamic Augmentation

    NASA Technical Reports Server (NTRS)

    Jones, Jonathan E.; Hawk, Clark W.

    1998-01-01

    A trade study of magnetohydrodynamic (MHD) augmented propulsion reveals a unique operating regime at lower thrust levels. Substantial mass savings are realized over conventional chemical, solar, and electrical propulsion concepts when MHD augmentation is used to obtain optimal I(sub sp). However, trip times for the most conservative estimates of power plant specific impulse and accelerator efficiency may be prohibitively long. Quasi-one-dimensional calculations show that a solar or nuclear thermal system augmented by MHD can provide competitive performance while utilizing a diverse range of propellants including water, which is available from the Space Shuttle, the Moon, asteroids, and various moons and planets within our solar system. The use of in-situ propellants will reduce costs of space operations as well as enable human exploration of our Solar System. The following conclusions can be drawn from the results of the mission trade study: (1) There exists a maximum thrust or mass flow rate above which MHD augmentation increases the initial mass in low earth orbit (LEO); (2) Mass saving of over 50% can be realized for unique combination of solar/MHD systems; (3) Trip times for systems utilizing current power supply technology may be prohibitively long. Theoretical predictions of MHD performance for in space propulsion systems show that improved efficiencies can reduce trip times to acceptable levels; (4) Long trip times indicative of low thrust systems can be shortened by an increase in the MHD accelerator efficiency or a decrease in the specific mass of the power supply and power processing unit; and (5) As for all propulsion concepts, missions with larger (Delta)v's benefit more from the increased specific impulse resulting from MHD augmentation. Using a quasi-one-dimensional analysis, the required operating conditions for a MHD accelerator to reach acceptable efficiencies are outlined. This analysis shows that substantial non-equilibrium ionization is

  19. Electric Propulsion Platforms at DFRC

    NASA Technical Reports Server (NTRS)

    Baraaclough, Jonathan

    2009-01-01

    electric propulsion technologies. DFRC will leverage its vast experience in flight test to assist in the integration and flight test phases of any electric propulsion program. DFRC s core competencies, that have particular relevance to the goals of the EPWG, include flight research planning and execution and providing aircraft test beds for researching and testing electric propulsion concepts and equipment. There are three flight regimes that the EPWG is focusing on: subsonic small GA and UAV, subsonic transport class, and supersonic. DFRC proposes two classes of test bed aircraft, to answer the early- and mid-phase testing requirements of all flight regimes the EPWG is concerned with. First, a highly efficient PIK motor glider will be used to test concepts and equipment associated with the subsonic GA and UAV aircraft regime (N+1). Second, a small fleet of subscale remotely-piloted aircraft test beds, similar to the X48B Blended Wing Body aircraft tested at Dryden, will be developed to answer the unique testing requirements of the subsonic GA and UAV, subsonic transport and possibly the supersonic class of aircraft (N+2, N+3). These aircraft can be tested in either serial stages or concurrent stages, depending on the actual test requirements and program schedules. Both classes of test bed aircraft are described below.

  20. Center for Advanced Space Propulsion

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Center for Advanced Space Propulsion (CASP) is part of the University of Tennessee-Calspan Center for Aerospace Research (CAR). It was formed in 1985 to take advantage of the extensive research faculty and staff of the University of Tennessee and Calspan Corporation. It is also one of sixteen NASA sponsored Centers established to facilitate the Commercial Development of Space. Based on investigators' qualifications in propulsion system development, and matching industries' strong intent, the Center focused its efforts in the following technical areas: advanced chemical propulsion, electric propulsion, AI/Expert systems, fluids management in microgravity, and propulsion materials processing. This annual report focuses its discussion in these technical areas.

  1. MTR BASEMENT. GENERAL ELECTRIC CONTROL CONSOLE FOR AIRCRAFT NUCLEAR PROPULSION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MTR BASEMENT. GENERAL ELECTRIC CONTROL CONSOLE FOR AIRCRAFT NUCLEAR PROPULSION EXPERIMENT NO. 1. INL NEGATIVE NO. 6510. Unknown Photographer, 9/29/1959 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  2. Micro electric propulsion feasibility

    NASA Technical Reports Server (NTRS)

    Aston, Graeme; Aston, Martha

    1992-01-01

    Miniature, 50 kg class, strategic satellites intended for extended deployment in space require an on-board propulsion capability to perform needed attitude control adjustments and drag compensation maneuvers. Even on such very small spacecraft, these orbit maintenance functions can be significant and result in a substantial propellant mass requirement. Development of advanced propulsion technology could reduce this propellant mass significantly, and thereby maximize the payload capability of these spacecraft. In addition, spacecraft maneuverability could be enhanced and/or multi-year mission lifetimes realized. These benefits cut spacecraft replacement costs, and reduce services needed to maintain the launch vehicles. For SDIO brilliant pebble spacecraft, a miniaturized hydrazine propulsion system provides both boost and divert thrust control. This type of propulsion system is highly integrated and is capable of delivering large thrust levels for short time periods. However, orbit maintenance functions such as drag make-up require only very small velocity corrections. Using the boost and/or divert thrusters for these small corrections exposes this highly integrated propulsion system to continuous on/off cycling and thereby increases the risk of system failure. Furthermore, since drag compensation velocity corrections would be orders of magnitude less than these thrusters were designed to deliver, their effective specific impulse would be expected to be lower when operated at very short pulse lengths. The net result of these effects would be a significant depletion of the on-board hydrazine propellant supply throughout the mission, and a reduced propulsion system reliability, both of which would degrade the interceptors usefulness. In addition to SDIO brilliant pebble spacecraft, comparably small spacecraft can be anticipated for other future strategic defense applications such as surveillance and communication. For such spacecraft, high capability and reliability

  3. Micro electric propulsion feasibility

    NASA Astrophysics Data System (ADS)

    Aston, Graeme; Aston, Martha

    1992-11-01

    Miniature, 50 kg class, strategic satellites intended for extended deployment in space require an on-board propulsion capability to perform needed attitude control adjustments and drag compensation maneuvers. Even on such very small spacecraft, these orbit maintenance functions can be significant and result in a substantial propellant mass requirement. Development of advanced propulsion technology could reduce this propellant mass significantly, and thereby maximize the payload capability of these spacecraft. In addition, spacecraft maneuverability could be enhanced and/or multi-year mission lifetimes realized. These benefits cut spacecraft replacement costs, and reduce services needed to maintain the launch vehicles. For SDIO brilliant pebble spacecraft, a miniaturized hydrazine propulsion system provides both boost and divert thrust control. This type of propulsion system is highly integrated and is capable of delivering large thrust levels for short time periods. However, orbit maintenance functions such as drag make-up require only very small velocity corrections. Using the boost and/or divert thrusters for these small corrections exposes this highly integrated propulsion system to continuous on/off cycling and thereby increases the risk of system failure. Furthermore, since drag compensation velocity corrections would be orders of magnitude less than these thrusters were designed to deliver, their effective specific impulse would be expected to be lower when operated at very short pulse lengths. The net result of these effects would be a significant depletion of the on-board hydrazine propellant supply throughout the mission, and a reduced propulsion system reliability, both of which would degrade the interceptors usefulness. In addition to SDIO brilliant pebble spacecraft, comparably small spacecraft can be anticipated for other future strategic defense applications such as surveillance and communication. For such spacecraft, high capability and reliability

  4. Propulsion at the Marshall Space Flight Center - A brief history

    NASA Technical Reports Server (NTRS)

    Jones, L. W.; Fisher, M. F.; Mccool, A. A.; Mccarty, J. P.

    1991-01-01

    The history of propulsion development at the NASA Marshall Space Flight Center is summarized, beginning with the development of the propulsion system for the Redstone missile. This course of propulsion development continues through the Jupiter IRBM, the Saturn family of launch vehicles and the engines that powered them, the Centaur upper stage and RL-10 engine, the Reactor In-Flight Test stage and the NERVA nuclear engine. The Space Shuttle Main Engine and Solid Rocket Boosters are covered, as are spacecraft propulsion systems, including the reaction control systems for the High Energy Astronomy Observatory and the Space Station. The paper includes a description of several technology efforts such as those in high pressure turbomachinery, aerospike engines, and the AS203 cyrogenic fluid management flight experiment. These and other propulsion projects are documented, and the scope of activities in support of these efforts at Marshall delineated.

  5. Propulsion at the Marshall Space Flight Center - A brief history

    NASA Technical Reports Server (NTRS)

    Jones, L. W.; Fisher, M. F.; Mccool, A. A.; Mccarty, J. P.

    1991-01-01

    The history of propulsion development at the NASA Marshall Space Flight Center is summarized, beginning with the development of the propulsion system for the Redstone missile. This course of propulsion development continues through the Jupiter IRBM, the Saturn family of launch vehicles and the engines that powered them, the Centaur upper stage and RL-10 engine, the Reactor In-Flight Test stage and the NERVA nuclear engine. The Space Shuttle Main Engine and Solid Rocket Boosters are covered, as are spacecraft propulsion systems, including the reaction control systems for the High Energy Astronomy Observatory and the Space Station. The paper includes a description of several technology efforts such as those in high pressure turbomachinery, aerospike engines, and the AS203 cyrogenic fluid management flight experiment. These and other propulsion projects are documented, and the scope of activities in support of these efforts at Marshall delineated.

  6. Irradiated homologous costal cartilage for augmentation rhinoplasty

    SciTech Connect

    Lefkovits, G. )

    1990-10-01

    Although the ideal reconstructive material for augmentation rhinoplasty continues to challenge plastic surgeons, there exists no report in the literature that confines the use of irradiated homologous costal cartilage, first reported by Dingman and Grabb in 1961, to dorsal nasal augmentation. The purpose of this paper is to present a retrospective analysis of the author's experience using irradiated homologous costal cartilage in augmentation rhinoplasty. Twenty-seven dorsal nasal augmentations were performed in 24 patients between 16 and 49 years of age with a follow-up ranging from 1 to 27 months. Good-to-excellent results were achieved in 83.3% (20 of 24). Poor results requiring revision were found in 16.7% (4 of 24). Complication rates included 7.4% infection (2 of 27) and 14.8% warping (4 of 27). The resorption rate was zero. These results compare favorably with other forms of nasal augmentation. Advantages and disadvantages of irradiated homologous costal cartilage are discussed.

  7. The Propulsion Center at MSFC

    NASA Technical Reports Server (NTRS)

    Gerrish, Harold; Schmidt, George R. (Technical Monitor)

    2000-01-01

    The Propulsion Research Center at MSFC serves as a national resource for research of advanced, revolutionary propulsion technologies. Our mission is to move the nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft like access to earth-orbit, rapid travel throughout the solar system, and exploration of interstellar space. Current efforts cover a wide range of exciting areas, including high-energy plasma thrusters, advanced fission and fusion engines, antimatter propulsion systems, beamed energy rockets and sails, and fundamental motive physics. Activities involve concept investigation, proof-of-concept demonstration, and breadboard validation of new propulsion systems. The Propulsion Research Center at MSFC provides an environment where NASA, national laboratories, universities, and industry researchers can pool their skills together to perform landmark propulsion achievements. We offer excellent educational opportunities to students and young researchers-fostering a wellspring of innovation that will revolutionize space transportation.

  8. The NASA Electric Propulsion program

    NASA Technical Reports Server (NTRS)

    Byers, D. C.

    1984-01-01

    It is pointed out that the NASA Electric Propulsion program is aimed at providing technology for auxiliary and primary propulsion functions for earth-orbital and planetary space missions. Efforts in electrostatic propulsion include analyses of ion propulsion for Geosynchronous (GEO) and planetary spacecraft, continued preflight efforts associated with the Ion Auxiliary Propulsion System (IAPS), and research and technology for advanced and simplified ion thruster systems. In the area of electromagnetic propulsion, studies were conducted regarding the feasibility and impacts of the use of electromagnetic launchers. Research on magnetoplasmadynamic (MPD) thrusters, electromagnetic launchers, and Hall current thrusters was also performed. Studies in the electrothermal sector included an evaluation of electric propulsion options for the Space Station, taking into account also resistojets, a pulsed electrothermal thruster, and arc jets.

  9. The Propulsion Center at MSFC

    NASA Technical Reports Server (NTRS)

    Gerrish, Harold; Schmidt, George R. (Technical Monitor)

    2000-01-01

    The Propulsion Research Center at MSFC serves as a national resource for research of advanced, revolutionary propulsion technologies. Our mission is to move the nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft like access to earth-orbit, rapid travel throughout the solar system, and exploration of interstellar space. Current efforts cover a wide range of exciting areas, including high-energy plasma thrusters, advanced fission and fusion engines, antimatter propulsion systems, beamed energy rockets and sails, and fundamental motive physics. Activities involve concept investigation, proof-of-concept demonstration, and breadboard validation of new propulsion systems. The Propulsion Research Center at MSFC provides an environment where NASA, national laboratories, universities, and industry researchers can pool their skills together to perform landmark propulsion achievements. We offer excellent educational opportunities to students and young researchers-fostering a wellspring of innovation that will revolutionize space transportation.

  10. Numerical Simulation of Pulse Detonation Rocket-Induced MHD Ejector (PDRIME) Concepts for Advanced Propulsion Systems

    DTIC Science & Technology

    2012-02-28

    with MHD acceleration of the airstream for thrust enhancement and control. The range of alternative MHD-augmented propulsion configurations that...electrical power can be applied to accelerate the air slug, generating thrust (Figure 1b). The procedure can then be repeated at each cycle. (a...bypass channel takes place. Another alternative configuration by which MHD can be used to augment thrust generated by a PDRE is one in which energy

  11. Propulsion System Choices and Their Implications

    NASA Technical Reports Server (NTRS)

    Joyner, Claude R., II; Levack, Daniel J. H.; Rhodes, Russell, E.; Robinson, John W.

    2010-01-01

    In defining a space vehicle architecture, the propulsion system and related subsystem choices will have a major influence on achieving the goals and objectives desired. There are many alternatives and the choices made must produce a system that meets the performance requirements, but at the same time also provide the greatest opportunity of reaching all of the required objectives. Recognizing the above, the SPST Functional Requirements subteam has drawn on the knowledge, expertise, and experience of its members, to develop insight that wiIJ effectively aid the architectural concept developer in making the appropriate choices consistent with the architecture goals. This data not only identifies many selected choices, but also, more importantly, presents the collective assessment of this subteam on the "pros" and the "cons" of these choices. The propulsion system choices with their pros and cons are presented in five major groups. A. System Integration Approach. Focused on the requirement for safety, reliability, dependability, maintainability, and low cost. B. Non-Chemical Propulsion. Focused on choice of propulsion type. C. Chemical Propulsion. Focused on propellant choice implications. D. Functional Integration. Focused on the degree of integration of the many propulsive and closely associated functions, and on the choice of the engine combustion power cycle. E. Thermal Management. Focused on propellant tank insulation and integration. Each of these groups is further broken down into subgroups, and at that level the consensus pros and cons are presented. The intended use of this paper is to provide a resource of focused material for architectural concept developers to use in designing new advanced systems including college design classes. It is also a possible source of input material for developing a model for designing and analyzing advanced concepts to help identify focused technology needs and their priorities.

  12. Overview of high performance aircraft propulsion research

    NASA Technical Reports Server (NTRS)

    Biesiadny, Thomas J.

    1992-01-01

    The overall scope of the NASA Lewis High Performance Aircraft Propulsion Research Program is presented. High performance fighter aircraft of interest include supersonic flights with such capabilities as short take off and vertical landing (STOVL) and/or high maneuverability. The NASA Lewis effort involving STOVL propulsion systems is focused primarily on component-level experimental and analytical research. The high-maneuverability portion of this effort, called the High Alpha Technology Program (HATP), is part of a cooperative program among NASA's Lewis, Langley, Ames, and Dryden facilities. The overall objective of the NASA Inlet Experiments portion of the HATP, which NASA Lewis leads, is to develop and enhance inlet technology that will ensure high performance and stability of the propulsion system during aircraft maneuvers at high angles of attack. To accomplish this objective, both wind-tunnel and flight experiments are used to obtain steady-state and dynamic data, and computational fluid dynamics (CFD) codes are used for analyses. This overview of the High Performance Aircraft Propulsion Research Program includes a sampling of the results obtained thus far and plans for the future.

  13. Hydrodynamics of Peristaltic Propulsion

    NASA Astrophysics Data System (ADS)

    Athanassiadis, Athanasios; Hart, Douglas

    2014-11-01

    A curious class of animals called salps live in marine environments and self-propel by ejecting vortex rings much like jellyfish and squid. However, unlike other jetting creatures that siphon and eject water from one side of their body, salps produce vortex rings by pumping water through siphons on opposite ends of their hollow cylindrical bodies. In the simplest cases, it seems like some species of salp can successfully move by contracting just two siphons connected by an elastic body. When thought of as a chain of timed contractions, salp propulsion is reminiscent of peristaltic pumping applied to marine locomotion. Inspired by salps, we investigate the hydrodynamics of peristaltic propulsion, focusing on the scaling relationships that determine flow rate, thrust production, and energy usage in a model system. We discuss possible actuation methods for a model peristaltic vehicle, considering both the material and geometrical requirements for such a system.

  14. STOL propulsion systems

    NASA Technical Reports Server (NTRS)

    Denington, R. J.; Koenig, R. W.; Vanco, M. R.; Sagerser, D. A.

    1972-01-01

    The selection and the characteristics of quiet, clean propulsion systems for STOL aircraft are discussed. Engines are evaluated for augmentor wing and externally blown flap STOL aircraft with the engines located both under and over the wings. Some supporting test data are presented. Optimum engines are selected based on achieving the performance, economic, acoustic, and pollution goals presently being considered for future STOL aircraft. The data and results presented were obtained from a number of contracted studies and some supporting NASA inhouse programs, most of which began in early 1972. The contracts include: (1) two aircraft and mission studies, (2) two propulsion system studies, (3) the experimental and analytic work on the augmentor wing, and (4) the experimental programs on Q-Fan. Engines are selected and discussed based on aircraft economics using the direct operating cost as the primary criterion. This cost includes the cost of the crew, fuel, aircraft, and engine maintenance and depreciation.

  15. Hybrid propulsion technology program

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Technology was identified which will enable application of hybrid propulsion to manned and unmanned space launch vehicles. Two design concepts are proposed. The first is a hybrid propulsion system using the classical method of regression (classical hybrid) resulting from the flow of oxidizer across a fuel grain surface. The second system uses a self-sustaining gas generator (gas generator hybrid) to produce a fuel rich exhaust that was mixed with oxidizer in a separate combustor. Both systems offer cost and reliability improvement over the existing solid rocket booster and proposed liquid boosters. The designs were evaluated using life cycle cost and reliability. The program consisted of: (1) identification and evaluation of candidate oxidizers and fuels; (2) preliminary evaluation of booster design concepts; (3) preparation of a detailed point design including life cycle costs and reliability analyses; (4) identification of those hybrid specific technologies needing improvement; and (5) preperation of a technology acquisition plan and large scale demonstration plan.

  16. Cryogenic Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Jones, David

    2011-01-01

    The CPS is an in-space cryogenic propulsive stage based largely on state of the practice design for launch vehicle upper stages. However, unlike conventional propulsive stages, it also contains power generation and thermal control systems to limit the loss of liquid hydrogen and oxygen due to boil-off during extended in-space storage. The CPS provides the necessary (Delta)V for rapid transfer of in-space elements to their destinations or staging points (i.e., E-M L1). The CPS is designed around a block upgrade strategy to provide maximum mission/architecture flexibility. Block 1 CPS: Short duration flight times (hours), passive cryo fluid management. Block 2 CPS: Long duration flight times (days/weeks/months), active and passive cryo fluid management.

  17. Electromagnetic propulsion for spacecraft

    NASA Technical Reports Server (NTRS)

    Myers, Roger M.

    1993-01-01

    Three electromagnetic propulsion technologies, solid propellant pulsed plasma thrusters (PPT), magnetoplasmadynamic (MPD) thrusters, and pulsed inductive thrusters (PIT) have been developed for application to auxiliary and primary spacecraft propulsion. Both the PPT and MPD thrusters have been flown in space, though only PPTs have been used on operational satellites. The performance of operational PPTs is quite poor, providing only about 8 percent efficiency at about 1000 sec specific impulse. Laboratory PPTs yielding 34 percent efficiency at 5170 sec specific impulse have been demonstrated. Laboratory MPD thrusters have been demonstrated with up to 70 percent efficiency and 7000 sec specific impulse. Recent PIT performance measurements using ammonia and hydrazine propellants are extremely encouraging, reaching 50 percent efficiency for specific impulses between 4000 and 8000 sec.

  18. Hypersonic missile propulsion system

    SciTech Connect

    Kazmar, R.R.

    1998-11-01

    Pratt and Whitney is developing the technology for hypersonic components and engines. A supersonic combustion ramjet (scramjet) database was developed using hydrogen fueled propulsion systems for space access vehicles and serves as a point of departure for the current development of hydrocarbon scramjets. The Air Force Hypersonic Technology (HyTech) Program has put programs in place to develop the technologies necessary to demonstrate the operability, performance and structural durability of an expendable, liquid hydrocarbon fueled scramjet system that operates from Mach 4 to 8. This program will culminate in a flight type engine test at representative flight conditions. The hypersonic technology base that will be developed and demonstrated under HyTech will establish the foundation to enable hypersonic propulsion systems for a broad range of air vehicle applications from missiles to space access vehicles. A hypersonic missile flight demonstration is planned in the DARPA Affordable Rapid Response Missile Demonstrator (ARRMD) program in 2001.

  19. Electromagnetic propulsion for spacecraft

    NASA Technical Reports Server (NTRS)

    Myers, Roger M.

    1993-01-01

    Three electromagnetic propulsion technologies, solid propellant pulsed plasma thrusters (PPT), magnetoplasmadynamic (MPD) thrusters, and pulsed inductive thrusters (PIT) have been developed for application to auxiliary and primary spacecraft propulsion. Both the PPT and MPD thrusters have been flown in space, though only PPTs have been used on operational satellites. The performance of operational PPTs is quite poor, providing only about 8 percent efficiency at about 1000 sec specific impulse. Laboratory PPTs yielding 34 percent efficiency at 5170 sec specific impulse have been demonstrated. Laboratory MPD thrusters have been demonstrated with up to 70 percent efficiency and 7000 sec specific impulse. Recent PIT performance measurements using ammonia and hydrazine propellants are extremely encouraging, reaching 50 percent efficiency for specific impulses between 4000 and 8000 sec.

  20. Digital MicroPropulsion

    DTIC Science & Technology

    2000-01-01

    Distribution Statement ‘A’, Approved for Public Release – Distribution Unlimited.” Abstract Arrays of “Digital Propulsion” micro -thrusters have been fabricated...and tested. A three- layer sandwich is fabricated containing micro -resistors, thrust chambers, and rupture di- aphragms. A propellant is loaded into...Micromechanics; Micro -propulsion; Micro -thrusters; Micro -rockets ∗Sensors and Actuators A, Physical, 2000, 80(2), pages 143-154. †Corresponding author, email

  1. Army Ground Vehicle Propulsion

    DTIC Science & Technology

    2012-09-25

    IV (> 75 bhp ) compliant COTS engines and directly integrate into current and new heavy-duty vehicles. • Combat vehicle: permanent armor...propulsion system volume [ bhp /ft3] — Air filtration requirements, thermal management system, transmission, engine, ducting requirements, final drives...transmission 40 ft3;  engine 31 ft3;  air filtration 31 ft3 o Bradley FIV: Cummins VTA903 has SHRR of 0.6 BHP / BHP vs. today’s COTS > 0.85

  2. Why Density Dependent Propulsion?

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.

    2011-01-01

    In 2004 Khoury and Weltman produced a density dependent cosmology theory they call the Chameleon, as at its nature, it is hidden within known physics. The Chameleon theory has implications to dark matter/energy with universe acceleration properties, which implies a new force mechanism with ties to the far and local density environment. In this paper, the Chameleon Density Model is discussed in terms of propulsion toward new propellant-less engineering methods.

  3. Emerging Propulsion Technologies

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.

    2006-01-01

    The Emerging Propulsion Technologies (EPT) investment area is the newest area within the In-Space Propulsion Technology (ISPT) Project and strives to bridge technologies in the lower Technology Readiness Level (TRL) range (2 to 3) to the mid TRL range (4 to 6). A prioritization process, the Integrated In-Space Transportation Planning (IISTP), was developed and applied in FY01 to establish initial program priorities. The EPT investment area emerged for technologies that scored well in the IISTP but had a low technical maturity level. One particular technology, the Momentum-eXchange Electrodynamic-Reboost (MXER) tether, scored extraordinarily high and had broad applicability in the IISTP. However, its technical maturity was too low for ranking alongside technologies like the ion engine or aerocapture. Thus MXER tethers assumed top priority at EPT startup in FY03 with an aggressive schedule and adequate budget. It was originally envisioned that future technologies would enter the ISP portfolio through EPT, and EPT developed an EPT/ISP Entrance Process for future candidate ISP technologies. EPT has funded the following secondary, candidate ISP technologies at a low level: ultra-lightweight solar sails, general space/near-earth tether development, electrodynamic tether development, advanced electric propulsion, and in-space mechanism development. However, the scope of the ISPT program has focused over time to more closely match SMD needs and technology advancement successes. As a result, the funding for MXER and other EPT technologies is not currently available. Consequently, the MXER tether tasks and other EPT tasks were expected to phased out by November 2006. Presentation slides are presented which provide activity overviews for the aerocapture technology and emerging propulsion technology projects.

  4. Interstellar Propulsion Concepts Assessment

    NASA Technical Reports Server (NTRS)

    Forward, Robert L.

    2000-01-01

    NASA is investigating the feasibility of conducting extra-solar and interstellar missions over the next 10 to 50 years. An assessment of technologies supporting these near and far term objectives is required. To help meet these objectives the Principal Investigator assessed the feasibility of candidate propulsion systems for the proposed 'Interstellar Probe', a mission to send a spacecraft to the Heliopause at 250 AU and beyond.

  5. Chemical propulsion technology

    NASA Technical Reports Server (NTRS)

    Priem, R. J.

    1980-01-01

    An overview of NASA's low thrust liquid chemical propulsion program is presented with particular emphasis on thrust system technology in the ten to one thousand pound thrust range. Key technology issues include high performance of cooled low thrust engines; small cryogenic pumps; multiple starts-shutdowns (10) with slow ramps (approximately 10 seconds); thrust variation - 4/1 in flight and 20/1 between flights; long life (100 hours); improved system weight and size; and propellant selection.

  6. Numerical Propulsion System Simulation

    NASA Technical Reports Server (NTRS)

    Naiman, Cynthia

    2006-01-01

    The NASA Glenn Research Center, in partnership with the aerospace industry, other government agencies, and academia, is leading the effort to develop an advanced multidisciplinary analysis environment for aerospace propulsion systems called the Numerical Propulsion System Simulation (NPSS). NPSS is a framework for performing analysis of complex systems. The initial development of NPSS focused on the analysis and design of airbreathing aircraft engines, but the resulting NPSS framework may be applied to any system, for example: aerospace, rockets, hypersonics, power and propulsion, fuel cells, ground based power, and even human system modeling. NPSS provides increased flexibility for the user, which reduces the total development time and cost. It is currently being extended to support the NASA Aeronautics Research Mission Directorate Fundamental Aeronautics Program and the Advanced Virtual Engine Test Cell (AVETeC). NPSS focuses on the integration of multiple disciplines such as aerodynamics, structure, and heat transfer with numerical zooming on component codes. Zooming is the coupling of analyses at various levels of detail. NPSS development includes capabilities to facilitate collaborative engineering. The NPSS will provide improved tools to develop custom components and to use capability for zooming to higher fidelity codes, coupling to multidiscipline codes, transmitting secure data, and distributing simulations across different platforms. These powerful capabilities extend NPSS from a zero-dimensional simulation tool to a multi-fidelity, multidiscipline system-level simulation tool for the full development life cycle.

  7. The MAP Propulsion Subsystem

    NASA Technical Reports Server (NTRS)

    Davis, Gary T.; Bauer, Frank H. (Technical Monitor)

    2002-01-01

    This paper describes the requirements, design, integration, test, performance, and lessons learned of NASA's Microwave Anisotropy Probe (MAP) propulsion subsystem. MAP was launched on a Delta-II launch vehicle from NASA's Kennedy Space Center on June 30, 2001. Due to instrument thermal stability requirements, the Earth-Sun L2 Lagrange point was selected for the mission orbit. The L2 trajectory incorporated phasing loops and a lunar gravity assist. The propulsion subsystem's requirements are to manage momentum, perform maneuvers during the phasing loops to set up the lunar swingby, and perform stationkeeping at L2 for 2 years. MAP's propulsion subsystem uses 8 thrusters which are located and oriented to provide attitude control and momentum management about all axes, and delta-V in any direction without exposing the instrument to the sun. The propellant tank holds 72 kg of hydrazine, which is expelled by unregulated blowdown pressurization. Thermal management is complex because no heater cycling is allowed at L2. Several technical challenges presented themselves during I and T, such as in-situ weld repairs and in-situ bending of thruster tubes to accommodate late changes in the observatory CG. On-orbit performance has been nominal, and all phasing loop, mid-course correction, and stationkeeping maneuvers have been successfully performed to date.

  8. Geosynchronous earth orbit base propulsion - electric propulsion options

    SciTech Connect

    Palaszewski, B.

    1987-01-01

    Electric propulsion and chemical propulsion requirements for a geosynchronous earth orbit (GEO) base were analyzed. The base is resupplied from the Space Station's low earth orbit. Orbit-transfer Delta-Vs, nodal-regression Delta-Vs and orbit-maintenance Delta-Vs were considered. For resupplying the base, a cryogenic oxygen/hydrogen (O2/H2) orbital transfer vehicle (OTV) is currently-baselined. Comparisons of several electric propulsion options with the O2/H2 OTV were conducted. Propulsion requirements for missions related to the GEO base were also analyzed. Payload data for the GEO missions were drawn from current mission data bases. Detailed electric propulsion module designs are presented. Mission analyses and propulsion analyses for the GEO-delivered payloads are included. 23 references.

  9. Propulsion for CubeSats

    NASA Astrophysics Data System (ADS)

    Lemmer, Kristina

    2017-05-01

    At present, very few CubeSats have flown in space featuring propulsion systems. Of those that have, the literature is scattered, published in a variety of formats (conference proceedings, contractor websites, technical notes, and journal articles), and often not available for public release. This paper seeks to collect the relevant publically releasable information in one location. To date, only two missions have featured propulsion systems as part of the technology demonstration. The IMPACT mission from the Aerospace Corporation launched several electrospray thrusters from Massachusetts Institute of Technology, and BricSAT-P from the United States Naval Academy had four micro-Cathode Arc Thrusters from George Washington University. Other than these two missions, propulsion on CubeSats has been used only for attitude control and reaction wheel desaturation via cold gas propulsion systems. As the desired capability of CubeSats increases, and more complex missions are planned, propulsion is required to accomplish the science and engineering objectives. This survey includes propulsion systems that have been designed specifically for the CubeSat platform and systems that fit within CubeSat constraints but were developed for other platforms. Throughout the survey, discussion of flight heritage and results of the mission are included where publicly released information and data have been made available. Major categories of propulsion systems that are in this survey are solar sails, cold gas propulsion, electric propulsion, and chemical propulsion systems. Only systems that have been tested in a laboratory or with some flight history are included.

  10. The Case of Nuclear Propulsion

    NASA Technical Reports Server (NTRS)

    Koroteev, Anatoly S.; Ponomarev-Stepnoi, Nicolai N.; Smetannikov, Vladimir P.; Gafarov, Albert A.; Houts, Mike; VanDyke, Melissa; Godfroy, Tom; Martin, James; Bragg-Sitton, Shannon; Dickens, Ricky

    2003-01-01

    Fission technology can enable rapid, affordable access to any point in the solar system. If fission propulsion systems are to be developed to their full potential; however, near-term customers must be identified and initial fission systems successfully developed, launched, and utilized. Successful utilization will simultaneously develop the infrastructure and experience necessary for developing even higher power and performance systems. To be successful, development programs must devise strategies for rapidly converting paper reactor concepts into actual flight hardware. One approach to accomplishing this is to design highly testable systems, and to structure the program to contain frequent, significant hardware milestones. This paper discusses ongoing efforts in Russia and the United States aimed at enabling near-term utilization of space fission systems.

  11. Augmentation of craniofacial defects using alloplastic material.

    PubMed

    Osunde, O D; Adebola, R A; Ver-or, N; Amole, I O; Akhiwu, B I; Jinjiri, N; Ladeinde, A; Ajike, S O; Efunkoya, A

    2013-09-01

    Alloplastic materials are increasingly being used in augmentation of craniofacial defects because of its ready availability, good aesthetic outcome and absence of donor site morbidity. This paper highlights experience in the use of heat-cured acrylic in augmentation cranioplasty. The management of three patients with anterior skull defect who presented at the Dental and Maxillofacial Surgery Clinic of the Aminu Kano Teaching Hospital over a five-year period is presented. There was good aesthetic outcome in all the patients and no complications were recorded. Augmentation of craniofacial defects using customized prefabricated heat-cured acrylic provides patients with a durable, stable and structural repair of craniofacial defects with good aesthetic outcome.

  12. In-Space Propulsion Solar Electric Propulsion Technology Overview

    NASA Astrophysics Data System (ADS)

    Dankanich, John W.

    2006-12-01

    NASA’s In-space Propulsion Technology Project is developing new propulsion technologies that can enable or enhance near and mid-term NASA science missions. The solar electric propulsion technology area has been investing in NASA’s Evolutionary Xenon Thruster (NEXT), the High Voltage Hall Accelerator (HiVHAC), lightweight reliable feed systems, wear testing and thruster modeling. These investments are specifically targeted to increase planetary science payload capability, expand the envelope of planetary science destinations, and significantly reduce the travel times, risk and cost of NASA planetary science missions. Current status and expected capabilities of the solar electric propulsion technologies will be discussed.

  13. Confronting an Augmented Reality

    ERIC Educational Resources Information Center

    Munnerley, Danny; Bacon, Matt; Wilson, Anna; Steele, James; Hedberg, John; Fitzgerald, Robert

    2012-01-01

    How can educators make use of augmented reality technologies and practices to enhance learning and why would we want to embrace such technologies anyway? How can an augmented reality help a learner confront, interpret and ultimately comprehend reality itself ? In this article, we seek to initiate a discussion that focuses on these questions, and…

  14. Subfascial gluteal augmentation.

    PubMed

    de la Peña, J Abel; Rubio, Omar V; Cano, Jacobo P; Cedillo, Mariana C; Garcés, Miriam T

    2006-07-01

    Developing the concept of gluteal augmentation through the past 17 years has been an academic adventure. During these years my coworkers and I have progressively improved surgical technique and devised an anatomical system for gluteal augmentation that includes an ideal implant design and templates to assist in evaluating patients in the preoperative period and to identify the most appropriate implant size.

  15. Equating of Augmented Subscores

    ERIC Educational Resources Information Center

    Sinharay, Sandip; Haberman, Shelby J.

    2011-01-01

    Recently, there has been an increasing level of interest in subscores for their potential diagnostic value. Haberman (2008b) suggested reporting an augmented subscore that is a linear combination of a subscore and the total score. Sinharay and Haberman (2008) and Sinharay (2010) showed that augmented subscores often lead to more accurate…

  16. Confronting an Augmented Reality

    ERIC Educational Resources Information Center

    Munnerley, Danny; Bacon, Matt; Wilson, Anna; Steele, James; Hedberg, John; Fitzgerald, Robert

    2012-01-01

    How can educators make use of augmented reality technologies and practices to enhance learning and why would we want to embrace such technologies anyway? How can an augmented reality help a learner confront, interpret and ultimately comprehend reality itself ? In this article, we seek to initiate a discussion that focuses on these questions, and…

  17. The Augmentation System Framework.

    ERIC Educational Resources Information Center

    Engelbart, Doug; Hooper, Kristina

    1986-01-01

    Augmentation systems are composed of things that will add to what the human is genetically endowed with in order to extend the net capabilities that a human or human organization can apply to the problems or goals of human society. A broad brush categorization of the components of an augmentation system includes three distinct though interacting…

  18. The Nuclear Cryogenic Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Borowski, Stanley K.; Scott, John

    2014-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP). Nuclear propulsion can be affordable and viable compared to other propulsion systems and must overcome a biased public fear due to hyper-environmentalism and a false perception of radiation and explosion risk.

  19. Heat transfer in aerospace propulsion

    NASA Technical Reports Server (NTRS)

    Simoneau, Robert J.; Hendricks, Robert C.; Gladden, Herbert J.

    1988-01-01

    Presented is an overview of heat transfer related research in support of aerospace propulsion, particularly as seen from the perspective of the NASA Lewis Research Center. Aerospace propulsion is defined to cover the full spectrum from conventional aircraft power plants through the Aerospace Plane to space propulsion. The conventional subsonic/supersonic aircraft arena, whether commercial or military, relies on the turbine engine. A key characteristic of turbine engines is that they involve fundamentally unsteady flows which must be properly treated. Space propulsion is characterized by very demanding performance requirements which frequently push systems to their limits and demand tailored designs. The hypersonic flight propulsion systems are subject to severe heat loads and the engine and airframe are truly one entity. The impact of the special demands of each of these aerospace propulsion systems on heat transfer is explored.

  20. Embedded Wing Propulsion Conceptual Study

    NASA Technical Reports Server (NTRS)

    Kim, Hyun D.; Saunders, John D.

    2003-01-01

    As a part of distributed propulsion work under NASA's Revolutionary Aeropropulsion Concepts or RAC project, a new propulsion-airframe integrated vehicle concept called Embedded Wing Propulsion (EWP) is developed and examined through system and computational fluid dynamics (CFD) studies. The idea behind the concept is to fully integrate a propulsion system within a wing structure so that the aircraft takes full benefits of coupling of wing aerodynamics and the propulsion thrust stream. The objective of this study is to assess the feasibility of the EWP concept applied to large transport aircraft such as the Blended-Wing-Body aircraft. In this paper, some of early analysis and current status of the study are presented. In addition, other current activities of distributed propulsion under the RAC project are briefly discussed.

  1. Definition of an arcjet propulsion sub-system

    NASA Technical Reports Server (NTRS)

    Price, Theodore W.

    1989-01-01

    An engineering flight demonstration of a 100 kW3 Space Reactor Power System is planned for the mid to late 1990s. An arcjet based propulsion subsystem will be included on the flight demonstraction as a secondary experiment. Two studies, sponsored by the Kay Technologies Directorate of the SDI Organization and managed by the Jet Propulsion Laboratory are currently under way to define that propulsion subsystem. The principal tasks of those contracts and the plans for two later phases, an experimental verification of the concept and a flight qualification/delivery of a flight unit, are described.

  2. Interface issues for on-board propulsion systems

    NASA Technical Reports Server (NTRS)

    Curran, Frank M.; Schneider, Steven J.

    1994-01-01

    Integration issues associated with the use of new chemical and electric propulsion technologies are a primary concern to the user community. Experience indicates that integration impacts must be addressed to the satisfaction of both spacecraft builders and operators prior to the acceptance of new propulsion systems. The NASA Lewis Research Center (LeRC) conducts an aggressive program to develop and transfer new propulsion technologies and this includes a major effort to identify and address integration issues associated with their use. This paper provides an overview of integration issues followed by a brief description of the spacecraft integration program at LeRC.

  3. Methane Propulsion Elements for Mars

    NASA Technical Reports Server (NTRS)

    Percy, Tom; Polsgrove, Tara; Thomas, Dan

    2017-01-01

    Human exploration beyond LEO relies on a suite of propulsive elements to: (1) Launch elements into space, (2) Transport crew and cargo to and from various destinations, (3) Provide access to the surface of Mars, (4) Launch crew from the surface of Mars. Oxygen/Methane propulsion systems meet the unique requirements of Mars surface access. A common Oxygen/Methane propulsion system is being considered to reduce development costs and support a wide range of primary & alternative applications.

  4. Propulsion PathFinder (PPF)

    NASA Technical Reports Server (NTRS)

    Marmie, John A.

    2015-01-01

    NASA's Propulsion PathFinder (PPF) project will flight test a variety of CubeSat propulsion systems in a relevant space environment, thereby elevating the Technology Readiness Level (TRL), or technology maturity level, of these subsystems to TRL 7. A series of flights are planned in low Earth orbit to characterize the performance of each propulsion system and demonstrate the capability to perform orbital maneuvers.

  5. Laser Diagnostics for Spacecraft Propulsion

    DTIC Science & Technology

    2015-10-13

    Briefing Charts 3. DATES COVERED (From - To) 21 September 2015 – 13 October 2015 4. TITLE AND SUBTITLE Laser Diagnostics for Spacecraft Propulsion 5a...Research Laboratory 68th Annual Gaseous Electronics Conference LASER DIAGNOSTICS FOR SPACECRAFT PROPULSION GEC15-2015-000599 Tuesday, October 13, 2015...Natalia MacDonald-Tenenbaum In-Space Propulsion Branch Air Force Research Laboratory Edwards AFB, CA natalia.macdonald@us.af.mil DISTRIBUTION A

  6. Future of Magnetohydrodynamic Ship Propulsion,

    DTIC Science & Technology

    1983-08-16

    83 FOREIGN TECHNOLOGY DIVISION FUTURE OF MAGNETOHYDRODYNAMIC SHIP PROPULSION by A.P. Baranov DTIQ ~E tJ Approved for public release; 0.. distribution...MAGNETOHYDRODYNAMIC SHIP PROPULSION By: A.P. Baranov -,English pages: 10 Source: Sudostroyeniye, Nr. 12, December 1966, pp. 3-6 . Country of origin: USSR X...equations, etc. merged into this translation were extracted from the best quality copy available. FUTURE OF MAGNETOHYDRODYNAMIC SHIP PROPULSION A. P

  7. 1995 JANNAF Propulsion Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Eggleston, Debra S. (Editor)

    1995-01-01

    This volume is a collection of 36 unclassified/unlimited distribution papers which were presented at the 1995 Joint Army-Navy-NASA-Air Force (JANNAF) propulsion meeting. Specific subjects discussed include the integrated High Payoff Rocket Propulsion Technology initiative, hybrid propulsion, electric propulsion, the Minuteman 2/3 missile system, slag, aluminum in propellant compositions, electric propulsion, rocket nozzle design, and tactical missiles.

  8. Transport Processes in Beamed Energy Propulsion Systems

    DTIC Science & Technology

    1991-11-01

    the advanced propulsion systems currently being considered for future space missions are the resistojet, arcjet , ion engines, and laser and microwave... electrothermal propulsion systems. Studies conducted of advanced propulsion concepts for both NASA and Air Force missions, such as low-earth orbit...advanced propulsion concepts mentioned, microwave electrothermal propulsion systems best suit this range of operation. Resistojets employ electrothermal

  9. Reactors for nuclear electric propulsion

    SciTech Connect

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades.

  10. Propulsion simulation for magnetically suspended wind tunnel models

    NASA Technical Reports Server (NTRS)

    Joshi, Prakash B.; Beerman, Henry P.; Chen, James; Krech, Robert H.; Lintz, Andrew L.; Rosen, David I.

    1990-01-01

    The feasibility of simulating propulsion-induced aerodynamic effects on scaled aircraft models in wind tunnels employing Magnetic Suspension and Balance Systems. The investigation concerned itself with techniques of generating exhaust jets of appropriate characteristics. The objectives were to: (1) define thrust and mass flow requirements of jets; (2) evaluate techniques for generating propulsive gas within volume limitations imposed by magnetically-suspended models; (3) conduct simple diagnostic experiments for techniques involving new concepts; and (4) recommend experiments for demonstration of propulsion simulation techniques. Various techniques of generating exhaust jets of appropriate characteristics were evaluated on scaled aircraft models in wind tunnels with MSBS. Four concepts of remotely-operated propulsion simulators were examined. Three conceptual designs involving innovative adaptation of convenient technologies (compressed gas cylinders, liquid, and solid propellants) were developed. The fourth innovative concept, namely, the laser-assisted thruster, which can potentially simulate both inlet and exhaust flows, was found to require very high power levels for small thrust levels.

  11. Sensitivity Analysis of Hybrid Propulsion Transportation System for Human Mars Expeditions

    NASA Technical Reports Server (NTRS)

    Chai, Patrick R.; Joyce, Ryan T.; Kessler, Paul D.; Merrill, Raymond G.; Qu, Min

    2017-01-01

    The National Aeronautics and Space Administration continues to develop and refine various transportation options to successfully field a human Mars campaign. One of these transportation options is the Hybrid Transportation System which utilizes both solar electric propulsion and chemical propulsion. The Hybrid propulsion system utilizes chemical propulsion to perform high thrust maneuvers, where the delta-V is most optimal when ap- plied to save time and to leverage the Oberth effect. It then utilizes solar electric propulsion to augment the chemical burns throughout the interplanetary trajectory. This eliminates the need for the development of two separate vehicles for crew and cargo missions. Previous studies considered single point designs of the architecture, with fixed payload mass and propulsion system performance parameters. As the architecture matures, it is inevitable that the payload mass and the performance of the propulsion system will change. It is desirable to understand how these changes will impact the in-space transportation system's mass and power requirements. This study presents an in-depth sensitivity analysis of the Hybrid crew transportation system to payload mass growth and solar electric propulsion performance. This analysis is used to identify the breakpoints of the current architecture and to inform future architecture and campaign design decisions.

  12. Advanced propulsion concepts

    NASA Technical Reports Server (NTRS)

    Sercel, Joel C.

    1991-01-01

    The topics presented are covered in viewgraph form. The programmatic objective is to establish the feasibility of propulsion technologies for vastly expanded space activity. The technical objective is a revolutionary performance sought, such as: (1) about 1 kg/kW specific mass; (2) specific impulse tailored to mission requirements; (3) ability to use in-situ resources; (4) round-trips to Mars in months; (5) round-trips to outer planets in 1 to 2 years; and (6) the capability for robotic mission beyond the solar system.

  13. Electromagnetic propulsion test facility

    NASA Technical Reports Server (NTRS)

    Gooder, S. T.

    1984-01-01

    A test facility for the exploration of electromagnetic propulsion concept is described. The facility is designed to accommodate electromagnetic rail accelerators of various lengths (1 to 10 meters) and to provide accelerating energies of up to 240 kiloJoules. This accelerating energy is supplied as a current pulse of hundreds of kiloAmps lasting as long as 1 millisecond. The design, installation, and operating characteristics of the pulsed energy system are discussed. The test chamber and its operation at pressures down to 1300 Pascals (10 mm of mercury) are described. Some aspects of safety (interlocking, personnel protection, and operating procedures) are included.

  14. Nuclear propulsion systems engineering

    SciTech Connect

    Madsen, W.W.; Neuman, J.E.: Van Haaften, D.H.

    1992-12-31

    The Nuclear Energy for Rocket Vehicle Application (NERVA) program of the 1960`s and early 1970`s was dramatically successful, with no major failures during the entire testing program. This success was due in large part to the successful development of a systems engineering process. Systems engineering, properly implemented, involves all aspects of the system design and operation, and leads to optimization of theentire system: cost, schedule, performance, safety, reliability, function, requirements, etc. The process must be incorporated from the very first and continued to project completion. This paper will discuss major aspects of the NERVA systems engineering effort, and consider the implications for current nuclear propulsion efforts.

  15. Nuclear propulsion systems engineering

    SciTech Connect

    Madsen, W.W.; Neuman, J.E.: Van Haaften, D.H.

    1992-01-01

    The Nuclear Energy for Rocket Vehicle Application (NERVA) program of the 1960's and early 1970's was dramatically successful, with no major failures during the entire testing program. This success was due in large part to the successful development of a systems engineering process. Systems engineering, properly implemented, involves all aspects of the system design and operation, and leads to optimization of theentire system: cost, schedule, performance, safety, reliability, function, requirements, etc. The process must be incorporated from the very first and continued to project completion. This paper will discuss major aspects of the NERVA systems engineering effort, and consider the implications for current nuclear propulsion efforts.

  16. Propulsion by tachyon beams

    SciTech Connect

    Powell, C.

    1989-07-01

    A possibility of generating collimated beams of faster-than-light particles (tachyons) and using them for rocket propulsion is explored. The relativistic rocket equations are derived, and are solved for a single-stage rocket with constant mass flow rate, constant exhaust velocity and no coasting period. The features of these solutions for faster-than-light exhaust velocities are discussed. It is shown that a tachyon drive would not violate the first law of thermodynamics. However, as seen in the Galactic frame, it would violate the second law.

  17. Miniature propulsion systems

    NASA Astrophysics Data System (ADS)

    Campbell, John G.

    1992-07-01

    Miniature solenoid valves, check valves and a hydrazine gas generator typify the miniaturization used in the liquid propulsion system for the Army Light Weight Exo-Atmospheric Projectile (LEAP). The pressure control subsystem uses a solenoid valve weighing 24 grams to control flow of helium to pressurize the propellant tanks. The attitude control subsystem uses a gas generator weighing 71 grams to produce decomposed hydrazine as the gaseous propellant for miniature 1 lbf ACS thrusters weighing 5.4 grams. The successful use of these miniature components in development tests and a hover test of the LEAP is described.

  18. Plug nozzle propulsion system

    NASA Astrophysics Data System (ADS)

    Heald, Dan A.

    1992-02-01

    General Dynamics studied a vertical takeoff/vertical landing fully reusable single-stage-to-orbit (SSTO) concept for medium payload missions. A hydrogen oxygen plug nozzle main engine integrates well in the wide aft end. The principal driver for its selection was the promise of very high I(sub SP), 480 seconds vacuum. Further, preliminary design and analysis with Rocketdyne showed uncertainties and performance losses degrading this number to 467.4 seconds. Nevertheless, this SSTO configuration appears to be optimum for a plug nozzle main engine system. The merits and risks of this propulsion system are discussed. Continued development is recommended.

  19. Development of An Intelligent Flight Propulsion Control System

    NASA Technical Reports Server (NTRS)

    Calise, A. J.; Rysdyk, R. T.; Leonhardt, B. K.

    1999-01-01

    The initial design and demonstration of an Intelligent Flight Propulsion and Control System (IFPCS) is documented. The design is based on the implementation of a nonlinear adaptive flight control architecture. This initial design of the IFPCS enhances flight safety by using propulsion sources to provide redundancy in flight control. The IFPCS enhances the conventional gain scheduled approach in significant ways: (1) The IFPCS provides a back up flight control system that results in consistent responses over a wide range of unanticipated failures. (2) The IFPCS is applicable to a variety of aircraft models without redesign and,(3) significantly reduces the laborious research and design necessary in a gain scheduled approach. The control augmentation is detailed within an approximate Input-Output Linearization setting. The availability of propulsion only provides two control inputs, symmetric and differential thrust. Earlier Propulsion Control Augmentation (PCA) work performed by NASA provided for a trajectory controller with pilot command input of glidepath and heading. This work is aimed at demonstrating the flexibility of the IFPCS in providing consistency in flying qualities under a variety of failure scenarios. This report documents the initial design phase where propulsion only is used. Results confirm that the engine dynamics and associated hard nonlineaaities result in poor handling qualities at best. However, as demonstrated in simulation, the IFPCS is capable of results similar to the gain scheduled designs of the NASA PCA work. The IFPCS design uses crude estimates of aircraft behaviour. The adaptive control architecture demonstrates robust stability and provides robust performance. In this work, robust stability means that all states, errors, and adaptive parameters remain bounded under a wide class of uncertainties and input and output disturbances. Robust performance is measured in the quality of the tracking. The results demonstrate the flexibility of

  20. Research on Electrostatic Propulsion Using C60 Molecules.

    DTIC Science & Technology

    2007-11-02

    fullerene extract containing C60 and C70 in a ratio of approximately 85% to 15%. The fullerene mix was Soxhlet extracted with toluene from soot. Pure C60...The objective of this program has been to determine properties of fullerenes relevant for electrostatic propulsion, to demonstrate ion extraction ...electrostatic propulsion, to demonstrate ion extraction from a discharge, and to assess the implications for fullerene ion thrusters. The experiments we

  1. Impact of dynamic loads on propulsion integration

    NASA Astrophysics Data System (ADS)

    Seiner, J. M.

    1994-09-01

    Aircraft dynamic loads produced by engine exhaust plumes are examined for a class of military fighter and bomber configurations in model and full scale. The configurations examined are associated with the USAF F-15 and B-1B aircraft, and the US F-18 HARV and ASTOVL programs. The experience gained as a result of these studies is used to formulate a level of understanding concerning this phenomena that could be useful at the preliminary stage of propulsion/airframe design.

  2. Abstraction Augmented Markov Models.

    PubMed

    Caragea, Cornelia; Silvescu, Adrian; Caragea, Doina; Honavar, Vasant

    2010-12-13

    High accuracy sequence classification often requires the use of higher order Markov models (MMs). However, the number of MM parameters increases exponentially with the range of direct dependencies between sequence elements, thereby increasing the risk of overfitting when the data set is limited in size. We present abstraction augmented Markov models (AAMMs) that effectively reduce the number of numeric parameters of k(th) order MMs by successively grouping strings of length k (i.e., k-grams) into abstraction hierarchies. We evaluate AAMMs on three protein subcellular localization prediction tasks. The results of our experiments show that abstraction makes it possible to construct predictive models that use significantly smaller number of features (by one to three orders of magnitude) as compared to MMs. AAMMs are competitive with and, in some cases, significantly outperform MMs. Moreover, the results show that AAMMs often perform significantly better than variable order Markov models, such as decomposed context tree weighting, prediction by partial match, and probabilistic suffix trees.

  3. Development Progress in Phase 1 Fission Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; VanDyke, Melissa; Godfroy, Tom; Martin, Jim; Dickens, Ricky; Pedersen, Kevin; Poston, David; Reid, Bob; Lipinski, Ron; Wright, Steve; hide

    2000-01-01

    Phase 1 fission propulsion systems are those fission propulsion systems that are highly testable and require no development of nuclear fuels or materials. The systems can be developed without new or significantly modified facilities, have adequate performance for numerous missions of interest, and demonstrate technologies and programmatics that are traceable to Phase 2 and Phase 3 systems. Phase 1 fission propulsion systems focus on safety, cost and schedule. Phase 1 flight units can be tested at full thrust using resistance heaters to simulate heat from fission. The development and use of Phase 1 systems will help enable Phase 2 or Phase 3 fission propulsion systems capable of giving rapid, affordable access to any point in the solar system. A Phase 1 fission propulsion system under development at the Marshall Space Flight Center (MSFC) in collaboration with individuals from Department of Energy Laboratories and industry is the Safe Affordable Fission Engine (SAFE). The propellant energy source of a 30 kW SAFE unit (SAFE-30) is being fabricated, and will begin testing at MSFC in FY00. The conceptual design of a 300 kW SAFE unit (SAFE-300)is nearing completion. Experiments have been performed on both SAFE-30 and SAFE-300 components. Module tests have confirmed the performance potential of the SAFE series of propulsion systems. This paper will report on the development status of the Phase 1 SAFE fission propulsion system.

  4. Space propulsion technology and cryogenic fluid depot

    NASA Technical Reports Server (NTRS)

    Diehl, Larry A.

    1988-01-01

    Information on space propulsion and technology and the cryogenic fluid depot is given in viewgraph form. Information is given on orbit transfer, electric propulsion, spacecraft propulsion, and program objectives.

  5. Additive Manufacturing of Aerospace Propulsion Components

    NASA Technical Reports Server (NTRS)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  6. Integrated airframe propulsion control

    NASA Technical Reports Server (NTRS)

    Fennell, R. E.; Black, S. B.

    1982-01-01

    Perturbation equations which describe flight dynamics and engine operation about a given operating point are combined to form an integrated aircraft/propulsion system model. Included in the model are the dependence of aerodynamic coefficients upon atmospheric variables along with the dependence of engine variables upon flight condition and inlet performance. An off-design engine performance model is used to identify interaction parameters in the model. Inclusion of subsystem interaction effects introduces coupling between flight and propulsion variables. To analyze interaction effects on control, consideration is first given to control requirements for separate flight and engine models. For the separate airframe model, feedback control provides substantial improvement in short period damping. For the integrated system, feedback control compensates for the coupling present in the model and provides good overall system stability. However, this feedback control law involves many non-zero gains. Analysis of suboptimal control strategies indicates that performance of the closed loop integrated system can be maintained with a feedback matrix in which the number of non-zero gains is small relative to the number of components in the feedback matrix.

  7. Assessing potential propulsion breakthroughs.

    PubMed

    Millis, Marc G

    2005-12-01

    The term, propulsion breakthrough, refers to concepts like propellantless space drives and faster-than-light travel, the kind of breakthroughs that would make interstellar exploration practical. Although no such breakthroughs appear imminent, a variety of investigations have begun. During 1996-2002 NASA supported the breakthrough propulsion physics project to examine physics in the context of breakthrough spaceflight. Three facets of these assessments are now reported: (1) predicting benefits, (2) selecting research, and (3) recent technical progress. Predicting benefits is challenging, since the breakthroughs are still only notional concepts, but energy can serve as a basis for comparison. A hypothetical space drive would require many orders of magnitude less energy than a rocket for journeys to our nearest neighboring star. Assessing research options is challenging when the goals are beyond known physics and when the implications of success are profound. To mitigate the challenges, a selection process is described where: (1) research tasks are constrained to only address the immediate unknowns, curious effects, or critical issues; (2) reliability of assertions is more important than their implications; and (3) reviewers judge credibility rather than feasibility. The recent findings of a number of tasks, some selected using this process, are discussed. Of the 14 tasks included, six reached null conclusions, four remain unresolved, and four have opportunities for sequels. A dominant theme with the sequels is research about the properties of space, inertial frames, and the quantum vacuum.

  8. Assessing Potential Propulsion Breakthroughs

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    2005-01-01

    The term, propulsion breakthrough, refers to concepts like propellantless space drives and faster-than-light travel, the kind of breakthroughs that would make interstellar exploration practical. Although no such breakthroughs appear imminent, a variety of investigations into these goals have begun. From 1996 to 2002, NASA supported the Breakthrough Propulsion Physics Project to examine physics in the context of breakthrough spaceflight. Three facets of these assessments are now reported: (1) predicting benefits, (2) selecting research, and (3) recent technical progress. Predicting benefits is challenging since the breakthroughs are still only notional concepts, but kinetic energy can serve as a basis for comparison. In terms of kinetic energy, a hypothetical space drive could require many orders of magnitude less energy than a rocket for journeys to our nearest neighboring star. Assessing research options is challenging when the goals are beyond known physics and when the implications of success are profound. To mitigate the challenges, a selection process is described where: (a) research tasks are constrained to only address the immediate unknowns, curious effects or critical issues, (b) reliability of assertions is more important than their implications, and (c) reviewers judge credibility rather than feasibility. The recent findings of a number of tasks, some selected using this process, are discussed. Of the 14 tasks included, six reached null conclusions, four remain unresolved, and four have opportunities for sequels. A dominant theme with the sequels is research about the properties of space, inertial frames, and the quantum vacuum.

  9. Jet propulsion without inertia

    NASA Astrophysics Data System (ADS)

    Spagnolie, Saverio E.; Lauga, Eric

    2010-08-01

    A body immersed in a highly viscous fluid can locomote by drawing in and expelling fluid through pores at its surface. We consider this mechanism of jet propulsion without inertia in the case of spheroidal bodies and derive both the swimming velocity and the hydrodynamic efficiency. Elementary examples are presented and exact axisymmetric solutions for spherical, prolate spheroidal, and oblate spheroidal body shapes are provided. In each case, entirely and partially porous (i.e., jetting) surfaces are considered and the optimal jetting flow profiles at the surface for maximizing the hydrodynamic efficiency are determined computationally. The maximal efficiency which may be achieved by a sphere using such jet propulsion is 12.5%, a significant improvement upon traditional flagella-based means of locomotion at zero Reynolds number, which corresponds to the potential flow created by a source dipole at the sphere center. Unlike other swimming mechanisms which rely on the presentation of a small cross section in the direction of motion, the efficiency of a jetting body at low Reynolds number increases as the body becomes more oblate and limits to approximately 162% in the case of a flat plate swimming along its axis of symmetry. Our results are discussed in the light of slime extrusion mechanisms occurring in many cyanobacteria.

  10. Emergent Propulsion Systems

    NASA Astrophysics Data System (ADS)

    El-Fakdi Sencianes, Andres

    2002-01-01

    almost an Engineer (2002 will be my last year as student) and the studies that I'm now ending here, in Girona, are closely related not only with science and technology subjects but with optimization and economic result obtention, too. Huge distances that separate us from everything in space have launched scientists and engineers into a new challenge: How to reach maximum speeds keeping high ratios payload/total spacecraft mass? The key limitation of chemical rockets is that their exhaust velocity is relatively low. Because achieving Earth orbit requires a high velocity change a rocket must carry far more propellant than payload. The answer to all this complications seems to stare in one way: electric propulsion systems and the possibility of taking advantatge of solar winds to thrust our crafts. possible solutions, some of them have been studied for years and now they are not a project but a reality; also newest theories bring us the possibility of dream. Improve of commom propellants, search of new ones: Investigators continued research on use of atomic species as high-energy-density propellants, which could increase the specific impulse of hydrogen/oxygen rockets by 50-150%. Nuclear fission propulsion: Centered in development of reactors for nearterm nuclear electric propulsion aplications. Multimegawatt systems based on vapor core reactors and magnetohydrodynamic power conversion. Engineers investigated new fuels for compact nuclear thermal propulsion systems. What is called plasma state?: When a gas is heated to tens of thousands or millions of degrees, atoms lose their electrons. The result is a "soup" of charged particles, or plasma, made up of negatively charged electrons and positively charged ions. No known material can contain the hot plasma necessary for rocket propulsion, but specially designed magnetic fields can. Plasma rockets: This rockets are not powered by conventional chemical reactions as today's rockets are, but by electrical energy that heats

  11. Exotic power and propulsion concepts

    NASA Technical Reports Server (NTRS)

    Forward, Robert L.

    1990-01-01

    The status of some exotic physical phenomena and unconventional spacecraft concepts that might produce breakthroughs in power and propulsion in the 21st Century are reviewed. The subjects covered include: electric, nuclear fission, nuclear fusion, antimatter, high energy density materials, metallic hydrogen, laser thermal, solar thermal, solar sail, magnetic sail, and tether propulsion.

  12. Simulation of Electric Propulsion Thrusters

    DTIC Science & Technology

    2011-01-01

    to convert electrical power into thrust and in general provide superior specific impulse in comparison to chemical systems. Electric propulsion has...generates thrust primarily from electrical energy through a number of different mechanisms. In general, electric thrusters provide superior...specific impulse and thrust associated with several types of electric propulsion systems. In addition to superior propellant mass efficiency, electric

  13. Progress in NASA Rotorcraft Propulsion

    NASA Technical Reports Server (NTRS)

    DellaCorte, Christopher; Johnson, Susan M.

    2008-01-01

    This presentation reviews recent progress made under NASA s Subsonic Rotary Wing (SRW) propulsion research activities. Advances in engines, drive systems and optimized propulsion systems are discussed. Progress in wide operability compressors, modeling of variable geometry turbine performance, foil gas bearings and multi-speed transmissions are presented.

  14. Chin augmentation - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100009.htm Chin augmentation - series—Normal anatomy To use the sharing features ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  15. Breast augmentation - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100205.htm Breast augmentation - series—Normal anatomy To use the sharing features ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  16. The NASA Electric Propulsion Program

    NASA Technical Reports Server (NTRS)

    Callahan, Lisa Wood; Curran, Francis M.

    1996-01-01

    Nearly all space missions require on-board propulsion systems and these systems typically have a major impact on spacecraft mass and cost. Electric propulsion systems offer major performance advantages over conventional chemical systems for many mission functions and the NASA Office of Space Access and Technology (OSAT) supports an extensive effort to develop the technology for high-performance, on-board electric propulsion system options to enhance and enable near- and far-term US space missions. This program includes research and development efforts on electrothermal, electrostatic, and electromagnetic propulsion system technologies to cover a wide range of potential applications. To maximize expectations of technology transfer, the program emphasizes strong interaction with the user community through a variety of cooperative and contracted approaches. This paper provides an overview of the OSAT electric propulsion program with an emphasis on recent progress and future directions.

  17. Mechanical efficiency of two commercial lever-propulsion mechanisms for manual wheelchair locomotion.

    PubMed

    Lui, Jordon; MacGillivray, Megan K; Sheel, A William; Jeyasurya, Jeswin; Sadeghi, Mahsa; Sawatzky, Bonita Jean

    2013-01-01

    The purpose of this study was to (1) evaluate the mechanical efficiency (ME) of two commercially available lever-propulsion mechanisms for wheelchairs and (2) compare the ME of lever propulsion with hand rim propulsion within the same wheelchair. Of the two mechanisms, one contained a torsion spring while the other used a roller clutch design. We hypothesized that the torsion spring mechanism would increase the ME of propulsion due to a passive recovery stroke enabled by the mechanism. Ten nondisabled male participants with no prior manual wheeling experience performed submaximal exercise tests using both lever-propulsion mechanisms and hand rim propulsion on two different wheelchairs. Cardiopulmonary parameters including oxygen uptake (VO2), heart rate (HR), and energy expenditure (En) were determined. Total external power (Pext) was measured using a drag test protocol. ME was determined by the ratio of Pext to En. Results indicated no significant effect of lever-propulsion mechanism for all physiological measures tested. This suggests that the torsion spring did not result in a physiological benefit compared with the roller clutch mechanism. However, both lever-propulsion mechanisms showed decreased VO2 and HR and increased ME (as a function of slope) compared with hand rim propulsion (p < 0.001). This indicates that both lever-propulsion mechanisms tested are more mechanically efficient than conventional hand rim propulsion, especially when slopes are encountered.

  18. Advanced transportation system studies. Alternate propulsion subsystem concepts: Propulsion database

    NASA Technical Reports Server (NTRS)

    Levack, Daniel

    1993-01-01

    The Advanced Transportation System Studies alternate propulsion subsystem concepts propulsion database interim report is presented. The objective of the database development task is to produce a propulsion database which is easy to use and modify while also being comprehensive in the level of detail available. The database is to be available on the Macintosh computer system. The task is to extend across all three years of the contract. Consequently, a significant fraction of the effort in this first year of the task was devoted to the development of the database structure to ensure a robust base for the following years' efforts. Nonetheless, significant point design propulsion system descriptions and parametric models were also produced. Each of the two propulsion databases, parametric propulsion database and propulsion system database, are described. The descriptions include a user's guide to each code, write-ups for models used, and sample output. The parametric database has models for LOX/H2 and LOX/RP liquid engines, solid rocket boosters using three different propellants, a hybrid rocket booster, and a NERVA derived nuclear thermal rocket engine.

  19. Media-Augmented Exercise Machines

    NASA Astrophysics Data System (ADS)

    Krueger, T.

    2002-01-01

    Cardio-vascular exercise has been used to mitigate the muscle and cardiac atrophy associated with adaptation to micro-gravity environments. Several hours per day may be required. In confined spaces and long duration missions this kind of exercise is inevitably repetitive and rapidly becomes uninteresting. At the same time, there are pressures to accomplish as much as possible given the cost- per-hour for humans occupying orbiting or interplanetary. Media augmentation provides a the means to overlap activities in time by supplementing the exercise with social, recreational, training or collaborative activities and thereby reducing time pressures. In addition, the machine functions as an interface to a wide range of digital environments allowing for spatial variety in an otherwise confined environment. We hypothesize that the adoption of media augmented exercise machines will have a positive effect on psycho-social well-being on long duration missions. By organizing and supplementing exercise machines, data acquisition hardware, computers and displays into an interacting system this proposal increases functionality with limited additional mass. This paper reviews preliminary work on a project to augment exercise equipment in a manner that addresses these issues and at the same time opens possibilities for additional benefits. A testbed augmented exercise machine uses a specialty built cycle trainer as both input to a virtual environment and as an output device from it using spatialized sound, and visual displays, vibration transducers and variable resistance. The resulting interactivity increases a sense of engagement in the exercise, provides a rich experience of the digital environments. Activities in the virtual environment and accompanying physiological and psychological indicators may be correlated to track and evaluate the health of the crew.

  20. Integrated Flight-propulsion Control Concepts for Supersonic Transport Airplanes

    NASA Technical Reports Server (NTRS)

    Burcham, Frank W., Jr.; Gilyard, Glenn B.; Gelhausen, Paul A.

    1990-01-01

    Integration of propulsion and flight control systems will provide significant performance improvements for supersonic transport airplanes. Increased engine thrust and reduced fuel consumption can be obtained by controlling engine stall margin as a function of flight and engine operating conditions. Improved inlet pressure recovery and decreased inlet drag can result from inlet control system integration. Using propulsion system forces and moments to augment the flight control system and airplane stability can reduce the flight control surface and tail size, weight, and drag. Special control modes may also be desirable for minimizing community noise and for emergency procedures. The overall impact of integrated controls on the takeoff gross weight for a generic high speed civil transport is presented.

  1. Propulsive Forces of a Biomimetic Undulating Fin

    NASA Astrophysics Data System (ADS)

    Kalumuck, Kenneth; Brandt, Alan; Armand, Mehran

    2007-11-01

    Understanding gained from much recent work on force production mechanisms of aquatic organisms holds great promise for improved undersea vehicle propulsion and maneuvering. One class of fish locomotion is that of the median fin utilized by animals such as squid, cuttlefish, knifefish, and seahorse. It is characterized by undulatory motion that creates traveling waves along the fin. Results of experiments conducted on a submerged mechanical underwater undulating fin test bed are presented. The 0.5 m long fin is mounted to a cylindrical body and consists of a flexible skin attached to ribs driven by an adjustable cam mechanism and variable speed motor that enables changing the characteristics of the undulating wave(s). Forces produced were measured in a captive mode under quiescent conditions as well in the presence of an ambient current. Propulsive forces are characterized as a function of the fin width, oscillation frequency, amplitude, and wavelength. Free swimming experiments were also conducted to determine the point of self propulsion. Flow field structure visualization using dye tracers is presented for selected cases. Estimates of performance and applications for use with larger scale vehicles are discussed.

  2. Main Propulsion for the Ares Projects

    NASA Technical Reports Server (NTRS)

    Sumrall, Phil

    2009-01-01

    The goal of this slide presentation is to provide an update on the status of the Ares propulsion systems. The Ares I is the vehicle to launch the crew and the Ares V is a heavy lift vehicle that is being designed to launch cargo into Low Earth Orbit (LEO) and transfer cargo and crews to the moon. The Ares propulsion systems are based on the heritage hardware and experiences from the Apollo project to the Space Shuttle and also to current expendable launch vehicles (ELVs). The presentation compares the various launch vehicles from the Saturn V to the space shuttle, including the planned details of the Ares I and V. There are slides detailing the elements of the Ares I and the Ares V, including views of the J2X upper stage engine that is to serve both the Ares I and V. The extent of the progress is reviewed.

  3. Pulsed plasmoid electric propulsion

    NASA Technical Reports Server (NTRS)

    Bourque, Robert F.; Parks, Paul B.; Tamano, Teruo

    1990-01-01

    A method of electric propulsion is explored where plasmoids such as spheromaks and field reversed configurations (FRC) are formed and then allowed to expand down a diverging conducting shell. The plasmoids contain a toroidal electric current that provides both heating and a confining magnetic field. They are free to translate because there are no externally supplied magnetic fields that would restrict motion. Image currents in the diverging conducting shell keep the plasmoids from contacting the wall. Because these currents translate relative to the wall, losses due to magnetic flux diffusion into the wall are minimized. During the expansion of the plasma in the diverging cone, both the inductive and thermal plasma energy are converted to directed kinetic energy producing thrust. Specific impulses can be in the 4000 to 20000 sec range with thrusts from 0.1 to 1000 Newtons, depending on available power.

  4. Anatomy of Nanoscale Propulsion.

    PubMed

    Yadav, Vinita; Duan, Wentao; Butler, Peter J; Sen, Ayusman

    2015-01-01

    Nature supports multifaceted forms of life. Despite the variety and complexity of these forms, motility remains the epicenter of life. The applicable laws of physics change upon going from macroscales to microscales and nanoscales, which are characterized by low Reynolds number (Re). We discuss motion at low Re in natural and synthetic systems, along with various propulsion mechanisms, including electrophoresis, electrolyte diffusiophoresis, and nonelectrolyte diffusiophoresis. We also describe the newly uncovered phenomena of motility in non-ATP-driven self-powered enzymes and the directional movement of these enzymes in response to substrate gradients. These enzymes can also be immobilized to function as fluid pumps in response to the presence of their substrates. Finally, we review emergent collective behavior arising from interacting motile species, and we discuss the possible biomedical applications of the synthetic nanobots and microbots.

  5. Space station propulsion

    NASA Technical Reports Server (NTRS)

    Jones, Robert E.; Morren, W. Earl; Sovey, James S.; Tacina, Robert R.

    1987-01-01

    Two propulsion systems have been selected for the space station: gaseous H/O rockets for high thrust applications and the multipropellant resistojets for low thrust needs. These two thruster systems integrate very well with the fluid systems on the space station, utilizing waste fluids as their source of propellant. The H/O rocket will be fueled by electrolyzed water and the resistojets will use waste gases collected from the environmental control system and the various laboratories. The results are presented of experimental efforts with H/O and resistojet thrusters to determine their performance and life capability, as well as results of studies to determine the availability of water and waste gases.

  6. Propulsion Systems Lab

    NASA Image and Video Library

    2015-04-14

    NASA Glenn’s Propulsion Systems Lab (PSL) is conducting research to characterize ice crystal clouds that can create a hazard to aircraft engines in certain conditions. With specialized equipment, scientists can create a simulated ice crystal cloud with the set of bars in the back spraying out a mist. The red area includes lasers, which measure the intensity of the cloud and a series of probes to measure everything from humidity to air pressure. The isokinetic probe (in gold) samples particles and the robotic arm (in orange) has a test tube on the end that catches ice particles for further measuring. NASA Glenn’s PSL is the only place in the world which can create these kind of ice crystal cloud conditions.

  7. Propulsion by directional adhesion

    NASA Astrophysics Data System (ADS)

    Bush, John; Prakash, Manu

    2008-03-01

    The rough, hairy integument of water-walking arthropods is well known to be responsible for their water-repellency; we here consider its additional propulsive role. We demonstrate that the tilted flexible leg hairs of water-walking arthropods render the leg cuticle directionally anisotropic: contact lines advance most readily towards the leg tips. The dynamical role of the resulting unidirectional adhesion is explored, and yields new insight into the manner in which water-walking arthropods generate thrust, glide and leap from the free surface. We thus provide new rationale for the fundamental topological difference in the roughness on plants and insects, and suggest novel directions for biomimetic design of smart, hydrophobic surfaces.

  8. Z-Pinch Pulsed Plasma Propulsion Technology Development

    NASA Technical Reports Server (NTRS)

    Polsgrove, Tara; Adams, Robert B.; Fabisinski, Leo; Fincher, Sharon; Maples, C. Dauphne; Miernik, Janie; Percy, Tom; Statham, Geoff; Turner, Matt; Cassibry, Jason; Cortez, Ross; Santarius, John

    2010-01-01

    Fusion-based propulsion can enable fast interplanetary transportation. Magneto-inertial fusion (MIF) is an approach which has been shown to potentially lead to a low cost, small reactor for fusion break even. The Z-Pinch/dense plasma focus method is an MIF concept in which a column of gas is compressed to thermonuclear conditions by an axial current (I approximates 100 MA). Recent advancements in experiments and the theoretical understanding of this concept suggest favorable scaling of fusion power output yield as I(sup 4). This document presents a conceptual design of a Z-Pinch fusion propulsion system and a vehicle for human exploration. The purpose of this study is to apply Z-Pinch fusion principles to the design of a propulsion system for an interplanetary spacecraft. This study took four steps in service of that objective; these steps are identified below. 1. Z-Pinch Modeling and Analysis: There is a wealth of literature characterizing Z-Pinch physics and existing Z-Pinch physics models. In order to be useful in engineering analysis, simplified Z-Pinch fusion thermodynamic models are required to give propulsion engineers the quantity of plasma, plasma temperature, rate of expansion, etc. The study team developed these models in this study. 2. Propulsion Modeling and Analysis: While the Z-Pinch models characterize the fusion process itself, propulsion models calculate the parameters that characterize the propulsion system (thrust, specific impulse, etc.) The study team developed a Z-Pinch propulsion model and used it to determine the best values for pulse rate, amount of propellant per pulse, and mixture ratio of the D-T and liner materials as well as the resulting thrust and specific impulse of the system. 3. Mission Analysis: Several potential missions were studied. Trajectory analysis using data from the propulsion model was used to determine the duration of the propulsion burns, the amount of propellant expended to complete each mission considered. 4

  9. Solar Thermal Propulsion Test Facility

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Researchers at the Marshall Space Flight Center (MSFC) have designed, fabricated and tested the first solar thermal engine, a non-chemical rocket engine that produces lower thrust but has better thrust efficiency than a chemical combustion engine. MSFC turned to solar thermal propulsion in the early 1990s due to its simplicity, safety, low cost, and commonality with other propulsion systems. Solar thermal propulsion works by acquiring and redirecting solar energy to heat a propellant. This photograph, taken at MSFC's Solar Thermal Propulsion Test Facility, shows a concentrator mirror, a combination of 144 mirrors forming this 18-ft diameter concentrator, and a vacuum chamber that houses the focal point. The 20- by 24-ft heliostat mirror (not shown in this photograph) has a dual-axis control that keeps a reflection of the sunlight on the 18-foot diameter concentrator mirror, which then focuses the sunlight to a 4-in focal point inside the vacuum chamber. The focal point has 10 kilowatts of intense solar power. As part of MSFC's Space Transportation Directorate, the Propulsion Research Center serves as a national resource for research of advanced, revolutionary propulsion technologies. The mission is to move the Nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft-like access to Earth-orbit, rapid travel throughout the solar system, and exploration of interstellar space.

  10. Augmented-plane-wave forces

    NASA Astrophysics Data System (ADS)

    Soler, José M.; Williams, Arthur R.

    1990-11-01

    Results are presented that demonstrate the effectiveness of a calculational method of electronic-structure theory. The method combines the power (tractable basis-set size) and flexibility (transition and first-row elements) of the augmented-plane-wave method with the computational efficiency of the Car-Parrinello method of molecular dynamics and total-energy minimization. Equilibrium geometry and vibrational frequencies in agreement with experiment are presented for Si, to demonstrate agreement with existing methods and for Cu, N2, and H2O to demonstrate the broader applicability of the approach.

  11. Propulsion Options For Interstellar Exploration

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Leifer, Stephanie

    2000-01-01

    NASA is considering missions to explore near-interstellar space (40 - 250 Astronomical Units) early in the next decade as the first step toward a vigorous interstellar exploration program. A key enabling technology for such an ambitious science and exploration effort is a propulsion system capable of providing fast trip times, yet which has low enough mass to allow for the use of inexpensive launch vehicles. Advanced propulsion technologies that might support the First interstellar precursor mission by the end of the first decade of the new millennium include solar sails and nuclear electric propulsion. Solar sails and electric propulsion are two technology areas that may hold promise for the next generation of interstellar precursor missions as well - perhaps a thousand astronomical units traveled in a professional lifetime. Future missions to far beyond the Heliosphere will require the development of propulsion technologies that are only at the conceptual stage today. For years, the scientific community has been interested in solar sail and electric propulsion technologies to support robotic exploration of the solar system. Progress in thin-film materials fabrication and handling, and advancement in technologies that may enable the deployment of large sails in space are only now maturing to the point where ambitious interstellar precursor missions using sails can be considered. Xenon ion propulsion is now being demonstrated for planetary exploration by the Deep Space 1 mission. The primary issues for the adaptation of electric propulsion to interstellar precursor applications include the development of low specific mass nuclear power systems, engine lifetime, and high power operation. Recent studies of interstellar precursor mission scenarios that use these propulsion systems will be described, and the range of application of each technology will be explored.

  12. Augmenting computer networks

    NASA Technical Reports Server (NTRS)

    Bokhari, S. H.; Raza, A. D.

    1984-01-01

    Three methods of augmenting computer networks by adding at most one link per processor are discussed: (1) A tree of N nodes may be augmented such that the resulting graph has diameter no greater than 4log sub 2((N+2)/3)-2. Thi O(N(3)) algorithm can be applied to any spanning tree of a connected graph to reduce the diameter of that graph to O(log N); (2) Given a binary tree T and a chain C of N nodes each, C may be augmented to produce C so that T is a subgraph of C. This algorithm is O(N) and may be used to produce augmented chains or rings that have diameter no greater than 2log sub 2((N+2)/3) and are planar; (3) Any rectangular two-dimensional 4 (8) nearest neighbor array of size N = 2(k) may be augmented so that it can emulate a single step shuffle-exchange network of size N/2 in 3(t) time steps.

  13. Enabling Electric Propulsion for Flight

    NASA Technical Reports Server (NTRS)

    Ginn, Starr Renee

    2015-01-01

    Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project, sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

  14. Enabling Electric Propulsion for Flight

    NASA Technical Reports Server (NTRS)

    Ginn, Starr

    2014-01-01

    Description of current ARMD projects; Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project (new ARMD reorg), sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

  15. NASA's Nuclear Thermal Propulsion Project

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Mitchell, Doyce P.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Clement, Steven; Borowski, Stanley K.; Scott, John; Power, Kevin P.

    2015-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation NTP system could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of a first generation NTP in the development of advanced nuclear propulsion systems could be analogous to the role of the DC- 3 in the development of advanced aviation. Progress made under the NTP project could also help enable high performance fission power systems and Nuclear Electric Propulsion (NEP).

  16. NASA research in aircraft propulsion

    NASA Technical Reports Server (NTRS)

    Beheim, M. A.

    1982-01-01

    A broad overview of the scope of research presently being supported by NASA in aircraft propulsion is presented with emphasis on Lewis Research Center activities related to civil air transports, CTOL and V/STOL systems. Aircraft systems work is performed to identify the requirements for the propulsion system that enhance the mission capabilities of the aircraft. This important source of innovation and creativity drives the direction of propulsion research. In a companion effort, component research of a generic nature is performed to provide a better basis for design and provides an evolutionary process for technological growth that increases the capabilities of all types of aircraft. Both are important.

  17. Combined microwave science and propulsion

    SciTech Connect

    Palaszewski, B.

    1989-01-01

    The combined use of high-power active science instruments and high-power electric propulsion is investigated with a view to new science opportunities and measurements on future planetary missions. An example of a comet rendezvous mission that could benefit from this combination is discussed. It was found that, with electric propulsion, the launch mass of the comet spacecraft could be reduced by 61-68 percent over the chemical propulsion baseline mission. This high-power spacecraft is also capable of delivering a significant high-power radar science payload to the comet. 28 references.

  18. Advanced Space Fission Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Borowski, Stanley K.

    2010-01-01

    Fission has been considered for in-space propulsion since the 1940s. Nuclear Thermal Propulsion (NTP) systems underwent extensive development from 1955-1973, completing 20 full power ground tests and achieving specific impulses nearly twice that of the best chemical propulsion systems. Space fission power systems (which may eventually enable Nuclear Electric Propulsion) have been flown in space by both the United States and the Former Soviet Union. Fission is the most developed and understood of the nuclear propulsion options (e.g. fission, fusion, antimatter, etc.), and fission has enjoyed tremendous terrestrial success for nearly 7 decades. Current space nuclear research and technology efforts are focused on devising and developing first generation systems that are safe, reliable and affordable. For propulsion, the focus is on nuclear thermal rockets that build on technologies and systems developed and tested under the Rover/NERVA and related programs from the Apollo era. NTP Affordability is achieved through use of previously developed fuels and materials, modern analytical techniques and test strategies, and development of a small engine for ground and flight technology demonstration. Initial NTP systems will be capable of achieving an Isp of 900 s at a relatively high thrust-to-weight ratio. The development and use of first generation space fission power and propulsion systems will provide new, game changing capabilities for NASA. In addition, development and use of these systems will provide the foundation for developing extremely advanced power and propulsion systems capable of routinely and affordably accessing any point in the solar system. The energy density of fissile fuel (8 x 10(exp 13) Joules/kg) is more than adequate for enabling extensive exploration and utilization of the solar system. For space fission propulsion systems, the key is converting the virtually unlimited energy of fission into thrust at the desired specific impulse and thrust

  19. Electric propulsion and interstellar flight

    SciTech Connect

    Matloff, G.L.

    1987-01-01

    Two general classes of interstellar space-flights are defined: endothermic and exothermic. Endothermic methods utilize power sources external to the vehicle and associated technology. Faster exothermic methods utilize on-board propulsive power sources or energy-beam technology. Various proposed endothermic electric propulsion methods are described. These include solar electric rockets, mass drivers, and ramjets. A review of previously suggested exothermic electric propulsion methods is presented. Following this review is a detailed discussion of possible near future application of the beamed-laser ramjet, mainly for ultimate relativistic travel. Electric/magnetic techniques offer an excellent possibility for decelerating an interstellar vehicle, regardless of the acceleration technique. 20 references.

  20. MSFC Nuclear Propulsion Materials Development

    NASA Technical Reports Server (NTRS)

    Rogers, J. R.; Cook, B.

    2004-01-01

    Nuclear propulsion systems for spacecraft applications present numerous technical challenges for propulsion systems. They have been the focus of a recent NRA. Challenges inclue: a nuclear reactor subsystem to produce thermal energy; a power conversion subsystem to convert the thermal energy into electrical energy; a propulsion subsystem that utilizes Hall effect thrusters; thruster technologies and high temperature materials to support subsystems. The MSFC Electrostatic Levitation (ESL) Facility provides an ideal platform for the study of high temperature and reactive materials. An overview of the facility and its capabilities will be presented.

  1. Human Performance Assessments when Using Augmented Reality for Navigation

    DTIC Science & Technology

    2006-06-01

    Human performance executing search and rescue type of navigation is one area that can benefit from augmented reality technology when the proper...landmarks. We briefly report on an experiment that demonstrated the benefits of augmented reality in a search and rescue task. Specifically, 120...participants, equally divided by gender, were tested in speed and accuracy using augmented reality in a search and rescue task. Accuracy performance was

  2. NASA Office of Aeronautics and Space Technology Summer Workshop. Volume 5: Propulsion technology panel, part 1

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Payload experiments which could be carried out in near earth space using the shuttle orbiter, its payload bay, the Spacelab, and/or some free-flying device that might be used for long duration testing were identified. Specific areas examined in terms of user requirements include: chemical propulsion, nuclear propulsion (fission, fussion, radioisotopes), and collected energy (coherent energy and solar electromagnetic energy). Cost reduction objectives for advanced propulsion technology development were also developed.

  3. Numerical comparison of convective heat transfer augmentation devices used in cooling channels of hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    Maldonado, Jaime J.

    1994-01-01

    Hypersonic vehicles are exposed to extreme thermal conditions compared to subsonic aircraft; therefore, some level of thermal management is required to protect the materials used. Normally, hypersonic vehicles experience the highest temperatures in the nozzle throat, and aircraft and propulsion system leading edges. Convective heat transfer augmentation techniques can be used in the thermal management system to increase heat transfer of the cooling channels in those areas. The techniques studied in this report are pin-fin, offset-fin, ribbed and straight roughened channel. A smooth straight channel is used as the baseline for comparing the techniques. SINDA '85, a lumped parameter finite difference thermal analyzer, is used to model the channels. Subroutines are added to model the fluid flow assuming steady one dimensional compressible flow with heat addition and friction. Correlations for convective heat transfer and friction are used in conjunction with the fluid flow analysis mentioned. As expected, the pin-fin arrangement has the highest heat transfer coefficient and the largest pressure drop. All the other devices fall in between the pin-fin and smooth straight channel. The selection of the best heat augmentation method depends on the design requirements. A good approach may be a channel using a combination of the techniques. For instance, several rows of pin-fins may be located at the region of highest heat flux, surrounded by some of the other techniques. Thus, the heat transfer coefficient is maximized at the region of highest heat flux while the pressure drop is not excessive.

  4. Safe, Compact Nuclear Propulsion: Solid Core Nuclear Propulsion Concept

    DTIC Science & Technology

    1988-10-01

    Tables E-l and E-2 for the USA. There are several major types of electric propulsion systems that can be broadly categorized into electrothermal ...electrostatic, and electromagnetic classes. Electrothermal thrusters simply heat a propellant fluid and then accelerate it through a nozzle, in a process very... electrothermal thrusters range no higher than 1500 sec and represent the low ena of the range attainable with electric propulsion. Flight-qualified E

  5. Mixing of Supersonic Jets in a RBCC Strutjet Propulsion System

    NASA Technical Reports Server (NTRS)

    Muller, S.; Hawk, Clark W.; Bakker, P. G.; Parkinson, D.; Turner, M.

    1998-01-01

    The Strutjet approach to Rocket Based Combined Cycle (RBCC) propulsion depends upon fuel-rich flows from the rocket nozzles and turbine exhaust products mixing with the ingested air for successful operation in the ramjet and scramjet modes. It is desirable to delay this mixing process in the air-augmented mode of operation present during take-off and low speed flight. A scale model of the Strutjet device was built and tested to investigate the mixing of the streams as a function of distance from the Strut exit plane in simulated sea level take-off conditions. The Planar Laser Induced Fluorescence (PLIF) diagnostic method has been employed to observe the mixing of the turbine exhaust gas with the gases from both the primary rockets and the ingested air. The ratio of the pressure in the turbine exhaust to that in the rocket nozzle wall at the point where the two jets meet, is the independent variable in these experiments. Tests were accomplished at values of 1.0 (the original design point), 1.5 and 2.0 for this parameter at 8 locations downstream of the rocket nozzle exit. The results illustrate the development of the mixing zone from the exit plane of the strut to a distance of about 18 equivalent rocket nozzle exit diameters downstream (18"). These images show the turbine exhaust to be confined until a short distance downstream. The expansion into the ingested air is more pronounced at a pressure ratio of 1.0 and 1.5 and shows that mixing with this air would likely begin at a distance of 2" downstream of the nozzle exit plane. Of the pressure ratios tested in this research, 2.0 is the best value for delaying the mixing at the operating conditions considered.

  6. Mixing of Supersonic Jets in a RBCC Strutjet Propulsion System

    NASA Technical Reports Server (NTRS)

    Muller, S.; Hawk, Clark W.; Bakker, P. G.; Parkinson, D.; Turner, M.

    1998-01-01

    The Strutjet approach to Rocket Based Combined Cycle (RBCC) propulsion depends upon fuel-rich flows from the rocket nozzles and turbine exhaust products mixing with the ingested air for successful operation in the ramjet and scramjet modes. It is desirable to delay this mixing process in the air-augmented mode of operation present during take-off and low speed flight. A scale model of the Strutjet device was built and tested to investigate the mixing of the streams as a function of distance from the Strut exit plane in simulated sea level take-off conditions. The Planar Laser Induced Fluorescence (PLIF) diagnostic method has been employed to observe the mixing of the turbine exhaust gas with the gases from both the primary rockets and the ingested air. The ratio of the pressure in the turbine exhaust to that in the rocket nozzle wall at the point where the two jets meet, is the independent variable in these experiments. Tests were accomplished at values of 1.0 (the original design point), 1.5 and 2.0 for this parameter at 8 locations downstream of the rocket nozzle exit. The results illustrate the development of the mixing zone from the exit plane of the strut to a distance of about 18 equivalent rocket nozzle exit diameters downstream (18"). These images show the turbine exhaust to be confined until a short distance downstream. The expansion into the ingested air is more pronounced at a pressure ratio of 1.0 and 1.5 and shows that mixing with this air would likely begin at a distance of 2" downstream of the nozzle exit plane. Of the pressure ratios tested in this research, 2.0 is the best value for delaying the mixing at the operating conditions considered.

  7. 46 CFR 130.120 - Propulsion control.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Propulsion control. 130.120 Section 130.120 Shipping... MISCELLANEOUS EQUIPMENT AND SYSTEMS Vessel Control § 130.120 Propulsion control. (a) Each vessel must have— (1) A propulsion-control system operable from the pilothouse; and (2) A means at each propulsion...

  8. 46 CFR 130.120 - Propulsion control.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Propulsion control. 130.120 Section 130.120 Shipping... MISCELLANEOUS EQUIPMENT AND SYSTEMS Vessel Control § 130.120 Propulsion control. (a) Each vessel must have— (1) A propulsion-control system operable from the pilothouse; and (2) A means at each propulsion...

  9. 46 CFR 130.120 - Propulsion control.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Propulsion control. 130.120 Section 130.120 Shipping... MISCELLANEOUS EQUIPMENT AND SYSTEMS Vessel Control § 130.120 Propulsion control. (a) Each vessel must have— (1) A propulsion-control system operable from the pilothouse; and (2) A means at each propulsion...

  10. 46 CFR 130.120 - Propulsion control.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Propulsion control. 130.120 Section 130.120 Shipping... MISCELLANEOUS EQUIPMENT AND SYSTEMS Vessel Control § 130.120 Propulsion control. (a) Each vessel must have— (1) A propulsion-control system operable from the pilothouse; and (2) A means at each propulsion...

  11. 1998 JANNAF Propulsion Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Eggleston, Debra S. (Editor)

    1998-01-01

    This volume, the first of four volumes, is a collection of 40 unclassified/unlimited-distribution papers which were presented at the 1998 Joint Army-Navy-NASA-Air Force (JANNAF) Propulsion Meeting (JPM), held 15-17 July 1998 at the Cleveland Marriott Downtown at Key Center and the Celebreeze Federal Building in Cleveland, Ohio. The 1998 JPM was co-located with the 1998 American Institute of Aeronautics and Astronautics Joint Propulsion Conference. Specific subjects discussed include reusable liquid boosters, controllable solid propulsion, advanced propellants for the 2.75' rocket system, air-turbo-rocket propulsion, issues in gun propulsion, electric propulsion, liquid engine turbomachinery, and new liquid propulsion technology.

  12. Unsteady propulsion in ground effects

    NASA Astrophysics Data System (ADS)

    Park, Sung Goon; Kim, Boyoung; Sung, Hyung Jin

    2016-11-01

    Many animals in nature experience hydrodynamic benefits by swimming or flying near the ground, and this phenomenon is commonly called 'ground effect'. A flexible fin flapping near the ground was modelled, inspired by animals swimming. A transverse heaving motion was prescribed at the leading edge, and the posterior parts of the fin were passively fluttering by the fin-fluid interaction. The fin moved freely horizontally in a quiescent flow, by which the swimming speed was dynamically determined. The fin-fluid interaction was considered by using the penalty immersed boundary method. The kinematics of the flexible fin was altered by flapping near the ground, and the vortex structures generated in the wake were deflected upward, which was qualitatively analyzed by using the vortex dipole model. The swimming speed and the thrust force of the fin increased by the ground effects. The hydrodynamic changes from flapping near the ground affected the required power input in two opposite ways; the increased and decreased hydrodynamic pressures beneath the fin hindered the flapping motion, increasing the power input, while the transversely reduced flapping motion induced the decreased power input. The Froude propulsive efficiency was increased by swimming in the ground effects Creative Research Initiatives (No. 2016-004749) program of the National Research Foundation of Korea (MSIP).

  13. Basic processes of plasma propulsion

    NASA Astrophysics Data System (ADS)

    Schrade, H. O.

    1985-02-01

    The acceleration mechanisms and the electrode effects in self magnetic pulsed and continuous MPD-arc thrusters were investigated. The magnetic thrust of a MPD-arc propulsion device increases with the square of current. An explanation is put foreward which also accounts for the electrode and insulator erosion. A plasma instability leads to a deviation off the axisymmetrical current distribution and hence to a current concentration on the anode surface. A simplified rotationally symmetric, two dimensional numerical methods to calculate the flow pressure and current density field for different thruster geometries was set up. The current contour and constant pressure lines of such a numerical calculation for the MPD-Thruster assuring isothermal conditions for the electrons and an isotropic behavior of the heavy particles are shown. To gain a better understanding of the cathode phenomenon and to minimize the erosion rate in MPD-arcs an experiment was initiated. The experimental set up is shown and is placed in a vacuum test vessel which allow pressure variations between 10 to the minus 3rd power and 10,000 Pa for different gases. The electrode system is energized by a pulse forming network of electrolytic capacitors delivering a rectangular current pulse lasting about 2 ns with currents which can be varied between several hundred amperes up to 101A. The test apparatus will determine the cathode attachment behavior, the mass loss, erosion rate and surface damage for different cathode materials under various aperating conditions.

  14. Propulsion by passive filaments and active flagella near boundaries

    NASA Astrophysics Data System (ADS)

    Evans, Arthur A.; Lauga, Eric

    2010-10-01

    Confinement and wall effects are known to affect the kinematics and propulsive characteristics of swimming microorganisms. When a solid body is dragged through a viscous fluid at constant velocity, the presence of a wall increases fluid drag, and thus the net force required to maintain speed has to increase. In contrast, recent optical trapping experiments have revealed that the propulsive force generated by human spermatozoa is decreased by the presence of boundaries. Here, we use a series of simple models to analytically elucidate the propulsive effects of a solid boundary on passively actuated filaments and model flagella. For passive flexible filaments actuated periodically at one end, the presence of the wall is shown to increase the propulsive forces generated by the filaments in the case of displacement-driven actuation, while it decreases the force in the case of force-driven actuation. In the case of active filaments as models for eukaryotic flagella, we demonstrate that the manner in which a solid wall affects propulsion cannot be known a priori, but is instead a nontrivial function of the flagellum frequency, wavelength, its material characteristics, the manner in which the molecular motors self-organize to produce oscillations (prescribed activity model or self-organized axonemal beating model), and the boundary conditions applied experimentally to the tethered flagellum. In particular, we show that in some cases, the increase in fluid friction induced by the wall can lead to a change in the waveform expressed by the flagella, which results in a decrease in their propulsive force.

  15. Implementation of an Online Database for Chemical Propulsion Systems

    NASA Technical Reports Server (NTRS)

    David B. Owen, II; McRight, Patrick S.; Cardiff, Eric H.

    2009-01-01

    The Johns Hopkins University, Chemical Propulsion Information Analysis Center (CPIAC) has been working closely with NASA Goddard Space Flight Center (GSFC); NASA Marshall Space Flight Center (MSFC); the University of Alabama at Huntsville (UAH); The Johns Hopkins University, Applied Physics Laboratory (APL); and NASA Jet Propulsion Laboratory (JPL) to capture satellite and spacecraft propulsion system information for an online database tool. The Spacecraft Chemical Propulsion Database (SCPD) is a new online central repository containing general and detailed system and component information on a variety of spacecraft propulsion systems. This paper only uses data that have been approved for public release with unlimited distribution. The data, supporting documentation, and ability to produce reports on demand, enable a researcher using SCPD to compare spacecraft easily, generate information for trade studies and mass estimates, and learn from the experiences of others through what has already been done. This paper outlines the layout and advantages of SCPD, including a simple example application with a few chemical propulsion systems from various NASA spacecraft.

  16. The Nuclear Cryogenic Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Borowski, Stanley K.; Scott, John

    2014-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progres made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP).

  17. SSME propulsion performance reconstruction techniques

    NASA Technical Reports Server (NTRS)

    Temple, Enoch C.

    1988-01-01

    In view of the complex flight operation of the Space Shuttle propulsion system together with an expected launch rate increase, the flight performance reconstruction process needs to be performed by automated computer programs. These programs must have the capability to quickly and reliably determine the true behavior of the various components of the propulsion system. For the flight reconstruction, measured values from the solid rocket motors, liquid engines, and trajectory are appraised through the Kalman filter technique to identify the most likely flight propulsion performance. A more detailed data collection program for the single SSME engine captive test firing evaluation is scheduled for startup in September of 1988. Engine performance evaluation for the captive test firing requires a reconstruction process that is similar to the process that is used for the flight reconstruction. Analytical tools that may be used to reconstruct a propulsion system's true performance under flight and/or test conditions are described.

  18. Propulsion issues, options and trades

    NASA Technical Reports Server (NTRS)

    Forsythe, Doug J.

    1986-01-01

    Several different types of propulsion concepts are discussed: pulsed fission; continuous nuclear fission; chemical; and chemical boost with advanced nuclear fission. Some of the key characteristics of each type are provided, and typical concepts of each are shown.

  19. Environmental benefits of chemical propulsion

    NASA Technical Reports Server (NTRS)

    Hayes, Joyce A.; Goldberg, Benjamin E.; Anderson, David M.

    1995-01-01

    This paper identifies the necessity of chemical propulsion to satellite usage and some of the benefits accrued through monitoring global resources and patterns, including the Global Climate Change Model (GCM). The paper also summarized how the satellite observations are used to affect national and international policies. Chemical propulsion, like all environmentally conscious industries, does provide limited, controlled pollutant sources through its manufacture and usage. However, chemical propulsion is the sole source which enables mankind to launch spacecraft and monitor the Earth. The information provided by remote sensing directly affects national and international policies designed to protect the environment and enhance the overall quality of life on Earth. The resultant of chemical propulsion is the capability to reduce overall pollutant emissions to the benefit of mankind.

  20. Vehicle Integrated Propulsion Research Tests

    NASA Technical Reports Server (NTRS)

    Lekki, John D.; Hunter, Gary W.; Simon, Don; Meredith, Roger; Wrbanek, John; Woike, Mark; Tokars, Roger; Guffanti, Marianne; Lyall, Eric

    2013-01-01

    Overview of the Vehicle Integrated Propulsion Research Tests in the Vehicle Systems Safety Technologies project. This overview covers highlights of the completed VIPR I and VIPR II tests and also covers plans for the VIPR III test.

  1. Trajectory correction propulsion for TOPS

    NASA Technical Reports Server (NTRS)

    Long, H. R.; Bjorklund, R. A.

    1972-01-01

    A blowdown-pressurized hydrazine propulsion system was selected to provide trajectory correction impulse for outer planet flyby spacecraft as the result of cost/mass/reliability tradeoff analyses. Present hydrazine component and system technology and component designs were evaluated for application to the Thermoelectric Outer Planet Spacecraft (TOPS); while general hydrazine technology was adequate, component design changes were deemed necessary for TOPS-type missions. A prototype hydrazine propulsion system was fabricated and fired nine times for a total of 1600 s to demonstrate the operation and performance of the TOPS propulsion configuration. A flight-weight trajectory correction propulsion subsystem (TCPS) was designed for the TOPS based on actual and estimated advanced components.

  2. An Analysis of Engagement in a Combination Indoor/Outdoor Augmented Reality Educational Game

    ERIC Educational Resources Information Center

    Folkestad, James; O'Shea, Patrick

    2011-01-01

    This paper describes the results of a qualitative analysis of video captured during a dual indoor/outdoor Augmented Reality experience. Augmented Reality is the layering of virtual information on top of the physical world. This Augmented Reality experience asked students to interact with the San Diego Museum of Art and the Botanical Gardens in San…

  3. Propulsion Flight-Test Fixture

    NASA Technical Reports Server (NTRS)

    Palumbo, Nate; Vachon, M. Jake; Richwine, Dave; Moes, Tim; Creech, Gray

    2003-01-01

    NASA Dryden Flight Research Center s new Propulsion Flight Test Fixture (PFTF), designed in house, is an airborne engine-testing facility that enables engineers to gather flight data on small experimental engines. Without the PFTF, it would be necessary to obtain such data from traditional wind tunnels, ground test stands, or laboratory test rigs. Traditionally, flight testing is reserved for the last phase of engine development. Generally, engines that embody new propulsion concepts are not put into flight environments until their designs are mature: in such cases, either vehicles are designed around the engines or else the engines are mounted in or on missiles. However, a captive carry capability of the PFTF makes it possible to test engines that feature air-breathing designs (for example, designs based on the rocket-based combined cycle) economically in subscale experiments. The discovery of unknowns made evident through flight tests provides valuable information to engine designers early in development, before key design decisions are made, thereby potentially affording large benefits in the long term. This is especially true in the transonic region of flight (from mach 0.9 to around 1.2), where it can be difficult to obtain data from wind tunnels and computational fluid dynamics. In January 2002, flight-envelope expansion to verify the design and capabilities of the PFTF was completed. The PFTF was flown on a specially equipped supersonic F-15B research testbed airplane, mounted on the airplane at a center-line attachment fixture, as shown in Figure 1. NASA s F-15B testbed has been used for several years as a flight-research platform. Equipped with extensive research air-data, video, and other instrumentation systems, the airplane carries externally mounted test articles. Traditionally, the majority of test articles flown have been mounted at the centerline tank-attachment fixture, which is a hard-point (essentially, a standardized weapon-mounting fixture

  4. Nuclear Propulsion in Space (1968)

    ScienceCinema

    None

    2016-07-12

    Project NERVA was an acronym for Nuclear Engine for Rocket Vehicle Application, a joint program of the U.S. Atomic Energy Commission and NASA managed by the Space Nuclear Propulsion Office (SNPO) at the Nuclear Rocket Development Station in Jackass Flats, Nevada U.S.A. Between 1959 and 1972, the Space Nuclear Propulsion Office oversaw 23 reactor tests, both the program and the office ended at the end of 1972.

  5. Theory for Plasma Rocket Propulsion

    NASA Astrophysics Data System (ADS)

    Grabbe, Crockett

    2009-11-01

    Electrical propulsion of rockets is developing potentially into the use of 3 different thrusters for future long-distance space missions that primarily involve plasma dynamics. These are the Magnetoplasmadynamic (MPD) Thruster, the Plasma Induction Thruster (PID), and the VASIMIR Thruster. The history of the development of electrical propulsion into these prospects and the current research of particularly the VASIMIR Thruster are reviewed. Theoretical questions that need to be addressed in that development are explored.

  6. Propulsion Induced Effects Test Program

    NASA Technical Reports Server (NTRS)

    Cappuccio, Gelsomina; Won, Mark; Bencze, Dan

    1999-01-01

    The objective of this milestone is to assess the propulsion/airframe integration characteristics of the Technology Concept Airplane and design variations through computational analysis and experimental subsonic through supersonic wind tunnel testing. The Milestone will generate a comprehensive CFD and wind tunnel data base of the baseline, and design variations. Emphasis will be placed on establishing the propulsion induced effects on the flight performance of the Technology Concept Airplane with all appropriate wind tunnel corrections.

  7. Nuclear Propulsion in Space (1968)

    SciTech Connect

    2012-06-23

    Project NERVA was an acronym for Nuclear Engine for Rocket Vehicle Application, a joint program of the U.S. Atomic Energy Commission and NASA managed by the Space Nuclear Propulsion Office (SNPO) at the Nuclear Rocket Development Station in Jackass Flats, Nevada U.S.A. Between 1959 and 1972, the Space Nuclear Propulsion Office oversaw 23 reactor tests, both the program and the office ended at the end of 1972.

  8. Hybrid Propulsion Technology Program

    NASA Technical Reports Server (NTRS)

    Jensen, G. E.; Holzman, A. L.

    1990-01-01

    Future launch systems of the United States will require improvements in booster safety, reliability, and cost. In order to increase payload capabilities, performance improvements are also desirable. The hybrid rocket motor (HRM) offers the potential for improvements in all of these areas. The designs are presented for two sizes of hybrid boosters, a large 4.57 m (180 in.) diameter booster duplicating the Advanced Solid Rocket Motor (ASRM) vacuum thrust-time profile and smaller 2.44 m (96 in.), one-quater thrust level booster. The large booster would be used in tandem, while eight small boosters would be used to achieve the same total thrust. These preliminary designs were generated as part of the NASA Hybrid Propulsion Technology Program. This program is the first phase of an eventual three-phaes program culminating in the demonstration of a large subscale engine. The initial trade and sizing studies resulted in preferred motor diameters, operating pressures, nozzle geometry, and fuel grain systems for both the large and small boosters. The data were then used for specific performance predictions in terms of payload and the definition and selection of the requirements for the major components: the oxidizer feed system, nozzle, and thrust vector system. All of the parametric studies were performed using realistic fuel regression models based upon specific experimental data.

  9. Asymmetrical Capacitors for Propulsion

    NASA Technical Reports Server (NTRS)

    Canning, Francis X.; Melcher, Cory; Winet, Edwin

    2004-01-01

    Asymmetrical Capacitor Thrusters have been proposed as a source of propulsion. For over eighty years, it has been known that a thrust results when a high voltage is placed across an asymmetrical capacitor, when that voltage causes a leakage current to flow. However, there is surprisingly little experimental or theoretical data explaining this effect. This paper reports on the results of tests of several Asymmetrical Capacitor Thrusters (ACTs). The thrust they produce has been measured for various voltages, polarities, and ground configurations and their radiation in the VHF range has been recorded. These tests were performed at atmospheric pressure and at various reduced pressures. A simple model for the thrust was developed. The model assumed the thrust was due to electrostatic forces on the leakage current flowing across the capacitor. It was further assumed that this current involves charged ions which undergo multiple collisions with air. These collisions transfer momentum. All of the measured data was consistent with this model. Many configurations were tested, and the results suggest general design principles for ACTs to be used for a variety of purposes.

  10. The Rosetta Propulsion System

    NASA Astrophysics Data System (ADS)

    Stramaccioni, D.

    2004-10-01

    Rosetta is the European Space Agency's mission which is aimed to comet Churyumov-Gerasimenko to perform a close inspection of its nucleus and of its coma. Its propulsion system is a bi-propellant system capable of providing both functions of attitude control and of V manoeuvring. The system is capable to deliver pure torques and pure forces for manoeuvring around the comet with a very weak gravitational field. The system operates mainly in blow-down mode, but it can be re- pressurised in flight twice for delivering with high efficiency and constant performance a total V of 2,300 m/s. This large V is required to rendezvous the comet and be inserted into its orbit. The wide range of operating conditions presented technical challenges from the standpoint of thrusters design as well as system configuration. In addition to the technical aspects, the programme presented also very challenging AIT aspects due to the one-year launch delay that imposed a re-scheduling of the entire mission.

  11. Pollution reducing aircraft propulsion

    SciTech Connect

    Tamura, R.

    1980-07-29

    An aircraft pollution reducing propulsion airfoil system comprising a wing having upper and lower surfaces comprising wing skin plates extending longitudinally on the wing and being spaced one from another in chordwise directions, spars extending into the wing between the surfaces, stringer ducts extending along internal sides of the wing surfaces, the stringers having relatively rigid surface-supporting structure and having outward directed openings extending across the wing surfaces, interrupting the wing surfaces between edges of the wing skin plates, the ducts thereby forming stringer structural elements supporting the wing skin plates, the outward directed openings of the stringer ducts being arranged perpendicularly to the wing surfaces in a leading portion of the wing and tangential to the wing surfaces in a trailing portion of the wing surfaces, suction means connected to the stringer ducts with perpendicular opening for drawing gas into the ducts through those openings and blowing means connected to the ducts with tangential openings for flowing gas out of the tangential openings, combustion means connected to the suction means and to the blowing meanas for accelerating gas through the means.

  12. Mars Rocket Propulsion System

    NASA Technical Reports Server (NTRS)

    Zubrin, Robert; Harber, Dan; Nabors, Sammy

    2008-01-01

    A report discusses the methane and carbon monoxide/LOX (McLOx) rocket for ascent from Mars as well as other critical space propulsion tasks. The system offers a specific impulse over 370 s roughly 50 s higher than existing space-storable bio-propellants. Current Mars in-situ propellant production (ISPP) technologies produce impure methane and carbon monoxide in various combinations. While separation and purification of methane fuel is possible, it adds complexity to the propellant production process and discards an otherwise useful fuel product. The McLOx makes such complex and wasteful processes unnecessary by burning the methane/CO mixtures produced by the Mars ISPP systems without the need for further refinement. Despite the decrease in rocket-specific impulse caused by the CO admixture, the improvement offered by concomitant increased propellant density can provide a net improvement in stage performance. One advantage is the increase of the total amount of propellant produced, but with a decrease in mass and complexity of the required ISPP plant. Methane/CO fuel mixtures also may be produced by reprocessing the organic wastes of a Moon base or a space station, making McLOx engines key for a human Lunar initiative or the International Space Station (ISS) program. Because McLOx propellant components store at a common temperature, very lightweight and compact common bulkhead tanks can be employed, improving overall stage performance further.

  13. Nuclear Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Mitchell, Sonny; Houts, Michael G.; Kim, Tony

    2015-01-01

    Development efforts in the United States for nuclear thermal propulsion (NTP) systems began with Project Rover (1955-1973) which completed 22 high-power rocket reactor tests. Results indicated that an NTP system with a high thrust-to-weight ratio and a specific impulse greater than 900 s would be feasible. John F. Kennedy, in his historic special address to Congress on the importance of Space on May 25, 1961, said, "First, I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to the Earth..." This was accomplished. He also said, "Secondly ... accelerate development of the Rover nuclear rocket. This gives promise of someday providing a means for even more exciting and ambitious exploration of space... to the very end of the solar system itself." The current NTP project focuses on demonstrating the affordability and viability of a fully integrated NTP system with emphasis on fuel fabrication and testing and an affordable development and qualification strategy. The goal is to enable NTP to be considered a mainstream option for supporting human Mars and other missions beyond Earth orbit.

  14. Solar Thermal Propulsion Test Facility

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Researchers at the Marshall Space Flight Center (MSFC) have designed, fabricated, and tested the first solar thermal engine, a non-chemical rocket engine that produces lower thrust but has better thrust efficiency than a chemical combustion engine. MSFC turned to solar thermal propulsion in the early 1990s due to its simplicity, safety, low cost, and commonality with other propulsion systems. Solar thermal propulsion works by acquiring and redirecting solar energy to heat a propellant. This photograph shows a fully assembled solar thermal engine placed inside the vacuum chamber at the test facility prior to testing. The 20- by 24-ft heliostat mirror (not shown in this photograph) has a dual-axis control that keeps a reflection of the sunlight on the 18-ft diameter concentrator mirror, which then focuses the sunlight to a 4-in focal point inside the vacuum chamber. The focal point has 10 kilowatts of intense solar power. As part of MSFC's Space Transportation Directorate, the Propulsion Research Center serves as a national resource for research of advanced, revolutionary propulsion technologies. The mission is to move theNation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft-like access to Earth orbit, rapid travel throughout the solar system, and exploration of interstellar space.

  15. Space and transatmospheric propulsion technology

    NASA Technical Reports Server (NTRS)

    Merkle, Charles; Stangeland, Maynard L.; Brown, James R.; Mccarty, John P.; Povinelli, Louis A.; Northam, G. Burton; Zukoski, Edward E.

    1994-01-01

    This report focuses primarily on Japan's programs in liquid rocket propulsion and propulsion for spaceplane and related transatmospheric areas. It refers briefly to Japan's solid rocket programs and to new supersonic air-breathing propulsion efforts. The panel observed that the Japanese had a carefully thought-out plan, a broad-based program, and an ambitious but achievable schedule for propulsion activity. Japan's overall propulsion program is behind that of the United States at the time of this study, but the Japanese are gaining rapidly. The Japanese are at the forefront in such key areas as advanced materials, enjoying a high level of project continuity and funding. Japan's space program has been evolutionary in nature, while the U.S. program has emphasized revolutionary advances. Projects have typically been smaller in Japan than in the United States, focusing on incremental advances in technology, with an excellent record of applying proven technology to new projects. This evolutionary approach, coupled with an ability to take technology off the shelf from other countries, has resulted in relatively low development costs, rapid progress, and enhanced reliability. Clearly Japan is positioned to be a world leader in space and transatmospheric propulsion technology by the year 2000.

  16. An Electronic Workshop on the Performance Seeking Control and Propulsion Controlled Aircraft Results of the F-15 Highly Integrated Digital Electronic Control Flight Research Program

    NASA Technical Reports Server (NTRS)

    Powers, Sheryll Goecke (Compiler)

    1995-01-01

    Flight research for the F-15 HIDEC (Highly Integrated Digital Electronic Control) program was completed at NASA Dryden Flight Research Center in the fall of 1993. The flight research conducted during the last two years of the HIDEC program included two principal experiments: (1) performance seeking control (PSC), an adaptive, real-time, on-board optimization of engine, inlet, and horizontal tail position on the F-15; and (2) propulsion controlled aircraft (PCA), an augmented flight control system developed for landings as well as up-and-away flight that used only engine thrust (flight controls locked) for flight control. In September 1994, the background details and results of the PSC and PCA experiments were presented in an electronic workshop, accessible through the Dryden World Wide Web (http://www.dfrc.nasa.gov/dryden.html) and as a compact disk.

  17. Augmentative & Alternative Communication

    ERIC Educational Resources Information Center

    Murphy, Patti

    2007-01-01

    There is no definitive recipe for augmentative and alternative communication (AAC) success, but its universal ingredients can be found at home. The main ones are: (1) Understanding that all children need to express themselves, however outgoing or shy they may be; (2) Willingness to embrace the technology that may help your child regardless of your…

  18. Augmented Reality Binoculars.

    PubMed

    Oskiper, Taragay; Sizintsev, Mikhail; Branzoi, Vlad; Samarasekera, Supun; Kumar, Rakesh

    2015-05-01

    In this paper we present an augmented reality binocular system to allow long range high precision augmentation of live telescopic imagery with aerial and terrain based synthetic objects, vehicles, people and effects. The inserted objects must appear stable in the display and must not jitter and drift as the user pans around and examines the scene with the binoculars. The design of the system is based on using two different cameras with wide field of view and narrow field of view lenses enclosed in a binocular shaped shell. Using the wide field of view gives us context and enables us to recover the 3D location and orientation of the binoculars much more robustly, whereas the narrow field of view is used for the actual augmentation as well as to increase precision in tracking. We present our navigation algorithm that uses the two cameras in combination with an inertial measurement unit and global positioning system in an extended Kalman filter and provides jitter free, robust and real-time pose estimation for precise augmentation. We have demonstrated successful use of our system as part of information sharing example as well as a live simulated training system for observer training, in which fixed and rotary wing aircrafts, ground vehicles, and weapon effects are combined with real world scenes.

  19. Augmented thermal bus

    NASA Technical Reports Server (NTRS)

    Schrage, Dean S. (Inventor)

    1993-01-01

    The present invention is directed to an augmented thermal bus. In the present design a plurity of thermo-electric heat pumps are used to couple a source plate to a sink plate. Each heat pump is individually controlled by a model based controller. The controller coordinates the heat pump to maintain isothermality in the source.

  20. Augmented Thermal Bus

    NASA Technical Reports Server (NTRS)

    Schrage, Dean S. (Inventor)

    1996-01-01

    The present invention is directed to an augmented thermal bus. In the present design a plurality of thermo-electric heat pumps are used to couple a source plate to a sink plate. Each heat pump is individually controlled by a model based controller. The controller coordinates the heat pumps to maintain isothermality in the source.