Science.gov

Sample records for converter station design

  1. Weather satellite picture receiving stations, APT digital scan converter

    NASA Technical Reports Server (NTRS)

    Vermillion, C. H.; Kamowski, J. C.

    1975-01-01

    The automatic picture transmission digital scan converter is used at ground stations to convert signals received from scanning radiometers to data compatible with ground equipment designed to receive signals from vidicons aboard operational meteorological satellites. Information necessary to understand the circuit theory, functional operation, general construction and calibration of the converter is provided. Brief and detailed descriptions of each of the individual circuits are included, accompanied by a schematic diagram contained at the end of each circuit description. Listings of integral parts and testing equipment required as well as an overall wiring diagram are included. This unit will enable the user to readily accept and process weather photographs from the operational meteorological satellites.

  2. Space Station design integration

    NASA Technical Reports Server (NTRS)

    Carlisle, Richard F.

    1988-01-01

    This paper discusses the top Program level design integration process which involves the integration of a US Space Station manned base that consists of both US and international Elements. It explains the form and function of the Program Requirements Review (PRR), which certifies that the program is ready for preliminary design, the Program Design Review (PDR), which certifies the program is ready to start the detail design, and the Critical Design Review (CDR), which certifies that the program is completing a design that meets the Program objectives. The paper also discusses experience, status to date, and plans for continued system integration through manufacturing, testing and final verification of the Space Station system performance.

  3. Space Station galley design

    NASA Technical Reports Server (NTRS)

    Trabanino, Rudy; Murphy, George L.; Yakut, M. M.

    1986-01-01

    An Advanced Food Hardware System galley for the initial operating capability (IOC) Space Station is discussed. Space Station will employ food hardware items that have never been flown in space, such as a dishwasher, microwave oven, blender/mixer, bulk food and beverage dispensers, automated food inventory management, a trash compactor, and an advanced technology refrigerator/freezer. These new technologies and designs are described and the trades, design, development, and testing associated with each are summarized.

  4. Power Station Design

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Kuljian Corporation provides design engineering and construction management services for power generating plants in more than 20 countries. They used WASP (Calculating Water and Steam Properties), a COSMIC program to optimize power station design. This enabled the company to substantially reduce lead time and software cost in a recent design project.

  5. Designing a Weather Station

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    The collection and analysis of weather data is crucial to the location of alternate energy systems like solar and wind. This article presents a design challenge that gives students a chance to design a weather station to collect data in advance of a large wind turbine installation. Data analysis is a crucial part of any science or engineering…

  6. New cat converter design for compressors cuts service time

    SciTech Connect

    Not Available

    1993-04-19

    GPM Gas Corp., Houston, has begun replacing its catalytic converters on compressor engines with a converter that saves time and effort in inspection and maintenance, especially for converters that are elevated and difficult to access. The replacement is the Hatchbak converter designed and patented by Johnson Matthey Environmental Products Group, Wayne, PA. Its removable hatch, secured by only eight bolts, eliminates the need to remove the entire converter from the exhaust piping and thereby significantly cuts down time. Of approximately 285 engines at 75 booster stations and 4 gas processing sites, more than 40 are equipped with catalytic converters, many elevated as much as 20 ft. GPM has replaced more than half its previous catalytic converters atop the engines with the new design. The paper briefly describes the maintenance headaches and the new design.

  7. Space Station Engineering Design Issues

    NASA Technical Reports Server (NTRS)

    Mcruer, Duane T.; Boehm, Barry W.; Debra, Daniel B.; Green, C. Cordell; Henry, Richard C.; Maycock, Paul D.; Mcelroy, John H.; Pierce, Chester M.; Stafford, Thomas P.; Young, Laurence R.

    1989-01-01

    Space Station Freedom topics addressed include: general design issues; issues related to utilization and operations; issues related to systems requirements and design; and management issues relevant to design.

  8. Modelling, analyses and design of switching converters

    NASA Technical Reports Server (NTRS)

    Cuk, S. M.; Middlebrook, R. D.

    1978-01-01

    A state-space averaging method for modelling switching dc-to-dc converters for both continuous and discontinuous conduction mode is developed. In each case the starting point is the unified state-space representation, and the end result is a complete linear circuit model, for each conduction mode, which correctly represents all essential features, namely, the input, output, and transfer properties (static dc as well as dynamic ac small-signal). While the method is generally applicable to any switching converter, it is extensively illustrated for the three common power stages (buck, boost, and buck-boost). The results for these converters are then easily tabulated owing to the fixed equivalent circuit topology of their canonical circuit model. The insights that emerge from the general state-space modelling approach lead to the design of new converter topologies through the study of generic properties of the cascade connection of basic buck and boost converters.

  9. Efficient Design in a DC to DC Converter Unit

    NASA Technical Reports Server (NTRS)

    Bruemmer, Joel E.; Williams, Fitch R.; Schmitz, Gregory V.

    2002-01-01

    Space Flight hardware requires high power conversion efficiencies due to limited power availability and weight penalties of cooling systems. The International Space Station (ISS) Electric Power System (EPS) DC-DC Converter Unit (DDCU) power converter is no exception. This paper explores the design methods and tradeoffs that were utilized to accomplish high efficiency in the DDCU. An isolating DC to DC converter was selected for the ISS power system because of requirements for separate primary and secondary grounds and for a well-regulated secondary output voltage derived from a widely varying input voltage. A flyback-current-fed push-pull topology or improved Weinberg circuit was chosen for this converter because of its potential for high efficiency and reliability. To enhance efficiency, a non-dissipative snubber circuit for the very-low-Rds-on Field Effect Transistors (FETs) was utilized, redistributing the energy that could be wasted during the switching cycle of the power FETs. A unique, low-impedance connection system was utilized to improve contact resistance over a bolted connection. For improved consistency in performance and to lower internal wiring inductance and losses a planar bus system is employed. All of these choices contributed to the design of a 6.25 KW regulated dc to dc converter that is 95 percent efficient. The methodology used in the design of this DC to DC Converter Unit may be directly applicable to other systems that require a conservative approach to efficient power conversion and distribution.

  10. Thermophotovoltaic Converter Design for Radioisotope Power Systems

    SciTech Connect

    Crowley, Christopher J.; Elkouh, Nabil A.; Murray, Susan; Murray, Christopher

    2004-02-04

    The development of lightweight, efficient power for emerging NASA missions and recent advances in thermophotovoltaic (TPV) conversion technology have renewed interest in combining radioisotope heat sources with photovoltaic energy conversion. Thermophotovoltaic power conversion uses advanced materials able to utilize a broader, spectrally tuned range of wavelengths for more efficient power conversion than solar cells. Spectral control, including selective emitters, TPV module, and filters, are key to high-efficiency operation. This paper outlines the mechanical, thermal, and optical designs for the converter, including the heat source, the selective emitter, filters, photovoltaic (PV) cells, and optical cavity components. Focus is on the emitter type and the band-gap of InGaAs PV cells in developing the design. Any component and converter data available at the time of publication will also be presented.

  11. Stability of large DC power systems using switching converters, with application to the International Space Station

    SciTech Connect

    Gholdston, E.W.; Karimi, K.; Lee, F.C.; Rajagopalan, J.; Panov, Y.; Manners, B.

    1996-12-31

    As space direct current (dc) power systems continue to grow in size, switching power converters are playing an ever larger role in power conditioning and control. When designing a large dc system using power converters are playing an ever larger role in power conditioning and control.When designing a large dc system using power converters of this type, special attention must be placed on the electrical stability of the system and of the individual loads on the system. In the design of the electric power system (EPS) of the International Space Station (ISS), the National Aeronautics and Space Administration (NASA) and its contractor team led by Boeing Defense and Space Group has placed a great deal of emphasis on designing for system and load stability. To achieve this goal, the team has expended considerable effort deriving a clear concept on defining system stability in both a general sense and specifically with respect to the space station. The ISS power system presents numerous challenges with respect to system stability, such as high power, complex sources and undefined loads. As a result, the program has derived an impedance specification approach for system stability. This approach is based on the significant relationship between source and load impedances and the effect of this relationship on system stability. This approach is limited in its applicability by the theoretical and practical limits on component designs as presented by each system segment. As a result, the overall approach to system stability implemented by the ISS program consists of specific hardware requirements coupled with extensive system analysis and hardware testing.

  12. Stability of large DC power systems using switching converters, with application to the international space station

    NASA Technical Reports Server (NTRS)

    Manners, B.; Gholdston, E. W.; Karimi, K.; Lee, F. C.; Rajagopalan, J.; Panov, Y.

    1996-01-01

    As space direct current (dc) power systems continue to grow in size, switching power converters are playing an ever larger role in power conditioning and control. When designing a large dc system using power converters of this type, special attention must be placed on the electrical stability of the system and of the individual loads on the system. In the design of the electric power system (EPS) of the International Space Station (ISS), the National Aeronautics and Space Administration (NASA) and its contractor team led by Boeing Defense & Space Group has placed a great deal of emphasis on designing for system and load stability. To achieve this goal, the team has expended considerable effort deriving a dear concept on defining system stability in both a general sense and specifically with respect to the space station. The ISS power system presents numerous challenges with respect to system stability, such as high power, complex sources and undefined loads. To complicate these issues, source and load components have been designed in parallel by three major subcontractors (Boeing, Rocketdyne, and McDonnell Douglas) with interfaces to both sources and loads being designed in different countries (Russia, Japan, Canada, Europe, etc.). These issues, coupled with the program goal of limiting costs, have proven a significant challenge to the program. As a result, the program has derived an impedance specification approach for system stability. This approach is based on the significant relationship between source and load impedances and the effect of this relationship on system stability. This approach is limited in its applicability by the theoretical and practical limits on component designs as presented by each system segment. As a result, the overall approach to system stability implemented by the ISS program consists of specific hardware requirements coupled with extensive system analysis and hardware testing. Following this approach, the ISS program plans to begin

  13. Load converter interactions with the secondary system in the Space Station Freedom power management and distribution DC test bed

    NASA Astrophysics Data System (ADS)

    Lebron, Ramon C.

    1992-08-01

    The NASA LeRC in Cleveland, Ohio, is responsible for the design, development, and assembly of the Space Station Freedom (SSF) Electrical Power System (EPS). In order to identify and understand system level issues during the SSF Program design and development phases, a system Power Management and Distribution (PMAD) DC test bed was assembled. Some of the objectives of this test bed facility are the evaluation of, system efficiency, power quality, system stability, and system protection and reconfiguration schemes. In order to provide a realistic operating scenario, dc Load Converter Units are used in the PMAD dc test bed to characterize the user interface with the power system. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. This final regulation is required on the actual space station because the majority of user loads will require voltage levels different from the secondary bus voltage. This paper describes the testing of load converters in an end to end system environment (from solar array to loads) where their interactions and compatibility with other system components are considered. Some of the system effects of interest that are presented include load converters transient behavior interactions with protective current limiting switchgear, load converters ripple effects, and the effects of load converter constant power behavior with protective features such as foldback.

  14. Load converter interactions with the secondary system in the Space Station Freedom power management and distribution DC test bed

    NASA Technical Reports Server (NTRS)

    Lebron, Ramon C.

    1992-01-01

    The NASA LeRC in Cleveland, Ohio, is responsible for the design, development, and assembly of the Space Station Freedom (SSF) Electrical Power System (EPS). In order to identify and understand system level issues during the SSF Program design and development phases, a system Power Management and Distribution (PMAD) DC test bed was assembled. Some of the objectives of this test bed facility are the evaluation of, system efficiency, power quality, system stability, and system protection and reconfiguration schemes. In order to provide a realistic operating scenario, dc Load Converter Units are used in the PMAD dc test bed to characterize the user interface with the power system. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. This final regulation is required on the actual space station because the majority of user loads will require voltage levels different from the secondary bus voltage. This paper describes the testing of load converters in an end to end system environment (from solar array to loads) where their interactions and compatibility with other system components are considered. Some of the system effects of interest that are presented include load converters transient behavior interactions with protective current limiting switchgear, load converters ripple effects, and the effects of load converter constant power behavior with protective features such as foldback.

  15. Load converter interactions with the secondary system in the Space Station Freedom power management and distribution dc test bed

    NASA Technical Reports Server (NTRS)

    Lebron, Ramon C.

    1992-01-01

    The NASA LeRC in Cleveland, Ohio, is responsible for the design, development, and assembly of the Space Station Freedom (SSF) Electrical Power System (EPS). In order to identify and understand system level issues during the SSF program design and development phases, a system Power Management and Distribution (PMAD) dc test bed was assembled. Some of the objectives of this test bed facility are the evaluation of, system efficiency, power quality, system stability, and system protection and reconfiguration schemes. In order to provide a realistic operating scenario, dc Load Converter Units are used in the PMAD dc test bed to characterize the user interface with the power system. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. This final regulation is required on the actual space station because the majority of user loads will require voltage levels different from the secondary bus voltage. This paper describes the testing of load converters in an end to end system environment (from solar array to loads) where their interactions and compatibility with other system components are considered. Some of the system effects of interest that are presented include load converters transient behavior interactions with protective current limiting switchgear, load converters ripple effects, and the effects of load converter constant power behavior with protective features such as foldback.

  16. Space Station Freedom Solar Array design development

    SciTech Connect

    Winslow, C. )

    1993-01-01

    The design of Space Station Freedom's Solar Array (SSFSA) is reviewed highlighting the key design performance goals, challenges, design description, and development testing objectives, results and plans. Study results are discussed which illustrate many of the more important design decision.

  17. Design knowledge capture for the space station

    NASA Technical Reports Server (NTRS)

    Crouse, K. R.; Wechsler, D. B.

    1987-01-01

    The benefits of design knowledge availability are identifiable and pervasive. The implementation of design knowledge capture and storage using current technology increases the probability for success, while providing for a degree of access compatibility with future applications. The space station design definition should be expanded to include design knowledge. Design knowledge should be captured. A critical timing relationship exists between the space station development program, and the implementation of this project.

  18. DC-DC power converter research for Orbiter/Station power exchange

    NASA Technical Reports Server (NTRS)

    Ehsani, M.

    1993-01-01

    This project was to produce innovative DC-DC power converter concepts which are appropriate for the power exchange between the Orbiter and the Space Station Freedom (SSF). The new converters must interface three regulated power buses on SSF, which are at different voltages, with three fuel cell power buses on the Orbiter which can be at different voltages and should be tracked independently. Power exchange is to be bi-directional between the SSF and the Orbiter. The new converters must satisfy the above operational requirements with better weight, volume, efficiency, and reliability than is available from the present conventional technology. Two families of zero current DC-DC converters were developed and successfully adapted to this application. Most of the converters developed are new and are presented.

  19. Spallation neutron source target station design, development, and commissioning

    NASA Astrophysics Data System (ADS)

    Haines, J. R.; McManamy, T. J.; Gabriel, T. A.; Battle, R. E.; Chipley, K. K.; Crabtree, J. A.; Jacobs, L. L.; Lousteau, D. C.; Rennich, M. J.; Riemer, B. W.

    2014-11-01

    The spallation neutron source target station is designed to safely, reliably, and efficiently convert a 1 GeV beam of protons to a high flux of about 1 meV neutrons that are available at 24 neutron scattering instrument beam lines. Research and development findings, design requirements, design description, initial checkout testing, and results from early operation with beam are discussed for each of the primary target subsystems, including the mercury target, neutron moderators and reflector, surrounding vessels and shielding, utilities, remote handling equipment, and instrumentation and controls. Future plans for the mercury target development program are also briefly discussed.

  20. Space Station Freedom natural environment design models

    NASA Technical Reports Server (NTRS)

    Suggs, Robert M.

    1993-01-01

    The Space Station Freedom program has established a series of natural environment models and databases for utilization in design and operations planning activities. The suite of models and databases that have either been selected from among internationally recognized standards or developed specifically for spacecraft design applications are presented. The models have been integrated with an orbit propagator and employed to compute environmental conditions for planned operations altitudes of Space Station Freedom.

  1. Design of a photovoltaic central power station

    SciTech Connect

    Not Available

    1984-02-01

    Photovoltaic central power station designs have been developed for both high-efficiency flat-panel arrays and two-axis tracking concentrator arrays. Both designs are based on a site adjacent to the Saguaro Power Station of Arizona Public Service. The plants are 100 MW each, made of 5 MW subfields. The site specific designs allow detailed cost estimate for site preparation, installation, and engineering. These designs are summarized and cost estimates analyzed. Provided also are recommendations for future work to reduce system cost for each plant design.

  2. Space station prototype Sabatier reactor design verification testing

    NASA Technical Reports Server (NTRS)

    Cusick, R. J.

    1974-01-01

    A six-man, flight prototype carbon dioxide reduction subsystem for the SSP ETC/LSS (Space Station Prototype Environmental/Thermal Control and Life Support System) was developed and fabricated for the NASA-Johnson Space Center between February 1971 and October 1973. Component design verification testing was conducted on the Sabatier reactor covering design and off-design conditions as part of this development program. The reactor was designed to convert a minimum of 98 per cent hydrogen to water and methane for both six-man and two-man reactant flow conditions. Important design features of the reactor and test conditions are described. Reactor test results are presented that show design goals were achieved and off-design performance was stable.

  3. German Point Of Load Converter Initiative To Design A Pol Converter Demonstrator For Space Application

    NASA Astrophysics Data System (ADS)

    Heyer, Heinz-Volker; Scheytt, Christoph; Scholz, Stefan; Teply, Florian; Sorge, Roland; Hasan, Arif; Ma, Yan; Grau, Gunter

    2011-10-01

    In satellites supporting broadcast and remote sensing the number of digital users with new CMOS technologies and decreased supply voltages is growing. The low voltages in digital devices (FPGAs, processors etc.) lead to high currents in the supply lines with the drawback of high voltage dropouts in the supply lines and bad dynamic behavior. The solution is the use of so-called Point-of-Load converters (POL) directly at the digital load with radiation hardness characteristics. The mixed signal ASIC technology of IHP (SGB25V) with LDMOS option will be used for designing the new POL converter that provided acceptable results from radiation tests at ATLAS [1, 2]. Some key components needed for radiation hardness of this technology are designed by advICo and thus both design teams will work together under research contract of an efficient buck or step down converter for POL applications from German Space Agency (DLR).

  4. Space station preliminary design report

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The results of a 3 month preliminary design and analysis effort is presented. The configuration that emerged consists of a very stiff deployable truss structure with an overall triangular cross section having universal modules attached at the apexes. Sufficient analysis was performed to show feasibility of the configuration. An evaluation of the structure shows that desirable attributes of the configuration are: (1) the solar cells, radiators, and antennas will be mounted to stiff structure to minimize control problems during orbit maintenance and correction, docking, and attitude control; (2) large flat areas are available for mounting and servicing of equipment; (3) Large mass items can be mounted near the center of gravity of the system to minimize gravity gradient torques; (4) the trusses are lightweight structures and can be transported into orbit in one Shuttle flight; (5) the trusses are expandable and will require a minimum of EVA; and (6) the modules are anticipated to be structurally identical except for internal equipment to minimize cost.

  5. Orbital Maneuvering Vehicle space station communications design

    NASA Technical Reports Server (NTRS)

    Arndt, D.; Novosad, S. W.; Tu, K.; Loh, Y. C.; Kuo, Y. S.

    1988-01-01

    The authors present an Orbital Maneuvering Vehicle space station communications systems design approach which is intended to satisfy the stringent link requirements. The operational scenario, system configuration, signal design, antenna system management, and link performance analysis are discussed in detail. It is shown that the return link can transmit up to 21.6 Mb/s and maintain at least a 3-dB link margin through proper power and antenna management control at a maximum distance of 37 km. It is suggested that the proposed system, which is compatible with the space station multiple-access system, can be a model for other space station interoperating elements or users to save the development cost and reduce the technical and schedule risks.

  6. Space station design - Innovation and compromise

    NASA Technical Reports Server (NTRS)

    Powell, L. E.; Cohen, A.; Craig, M.

    1984-01-01

    The NASA manned space station will consist of three main elements: habitable modules, solar collectors, and their interconnecting hardware. The most arduous of the requirements to be met by this configuration is the simultaneous integration of terrestrial, solar, and celestial viewing instruments, since omnidirectional simultaneous viewing is made difficult by the station's large solar energy collection devices. The space station also imposes unique design conditions on individual subsystems, such as the power distribution and energy storage hardware. In particular, the thermal control subsystem must be designed to meet a variety of mission, payload, and housekeeping tasks that demand a large heat rejection capacity. Novel environmental control and life support subsystem technology will be indispensable.

  7. Technical Design Report, Second Target Station

    SciTech Connect

    Galambos, John D.; Anderson, David E.; Bechtol, D.; Bethea, Katie L.; Brown, N.; Carden, W. F.; Chae, Steven M.; Clark, A.; Counce, Deborah M.; Craft, K.; Crofford, Mark T.; Collins, Richard M.; Cousineau, Sarah M.; Curry, Douglas E.; Cutler, Roy I.; Dayton, Michael J.; Dean, Robert A.; Deibele, Craig E.; Doleans, Marc; Dye, T.; Eason, Bob H.; Eckroth, James A.; Fincrock, C.; Fritts, S.; Gallmeier, Franz X.; Gawne, Ken R.; Hartman, Steven M.; Herwig, Kenneth W.; Hess, S.; Holmes, Jeffrey A.; Horak, Charlie M.; Howell, Matthew P.; Iverson, Erik B.; Jacobs, Lorelei L.; Jones, Larry C.; Johnson, B.; Johnson, S.; Kasemir, Kay; Kim, Sang-Ho; Laughon, Gregory J.; Lu, W.; Mahoney, Kelly L.; Mammosser, John; McManamy, T.; Michilini, M.; Middendorf, Mark E.; O'Neal, Ed; Nemec, B.; Peters, Roy Cecil; Plum, Michael A.; Reagan, G.; Remec, Igor; Rennich, Mark J.; Riemer, Bernie; Saethre, Robert B.; Schubert, James Phillip; Shishlo, Andrei P.; Smith, C. Craig; Strong, William Herb; Tallant, Kathie M.; Tennant, David Alan; Thibadeau, Barbara M.; Trumble, S.; Trotter, Steven M.; Wang, Z.; Webb, Steven B.; Williams, Derrick C.; White, Karen S.; Zhao, Jinkui

    2015-01-01

    The Second Target Station (STS) is a proposed upgrade for SNS. It includes a doubling of the accelerator power and an additional instrument hall. The new instrument hall will receive a 467 kW 10 Hz beam. The parameters and preliminary design aspects of the STS are presented for the accelerator, target systems, instrument hall, instruments and civil construction aspects.

  8. Space Station battery system design and development

    NASA Technical Reports Server (NTRS)

    Haas, R. J.; Chawathe, A. K.; Van Ommering, G.

    1988-01-01

    The Space Station Electric Power System will rely on nickel-hydrogen batteries in its photovoltaic power subsystem for energy storage to support eclipse and contingency operations. These 81-Ah batteries will be designed for a 5-year life capability and are configured as orbital replaceable units (ORUs), permitting replacement of worn-out batteries over the anticipated 30-year Station life. This paper describes the baseline design and the development plans for the battery assemblies, the battery ORUs and the battery system. Key elements reviewed are the cells, mechanical and thermal design of the assembly, the ORU approach and interfaces, and the electrical design of the battery system. The anticipated operational approach is discussed, covering expected performance as well as the processor-controlled charge management and discharge load allocation techniques. Development plans cover verification of materials, cells, assemblies and ORUs, as well as system-level test and analyses.

  9. Design and operation of a thermionic converter in air

    SciTech Connect

    Horner, M.H.; Begg, L.L.; Smith, J.N. Jr.; Geller, C.B.; Kallnowski, J.E.

    1995-01-01

    An electrically heated thermionic converter has been designed, built and successfully tested in air. Several unique features were incorporated in this converter: an integral cesium reservoir, innovative ceramic-to-metal seals, a heat rejection system coupling the collector to a low temperature heat sink and an innovative cylindrical heater filament. The converter was operated for extended periods of time with the emitter at about 1900 K. the collector at about 700 K, and a power density of over 2 w(e)/sq. cm. Input power transients were run between 50% and 100% thermal power, at up to 1% per second, without instabilities in performance.

  10. Designing A Mode Converter For Use With A Gyrotron

    NASA Technical Reports Server (NTRS)

    Hoppe, Daniel J.

    1995-01-01

    Report describes process of designing corrugated, circular-cross-section length of waveguide converting input electromagnetic radiation at frequency of 34.5 GHz in TM(11) mode to output radiation in HE(11) mode. TM(11)-mode input radiation supplied by gyrotron generating continuous-wave power of 200 kW at 34.5 GHz in TE(01) mode followed by TE(01)-to-TM(11) mode converter. Together, gyrotron and mode converters constitute prototype high-power transmitter for long-distance free-space communication.

  11. Space station proximity operations and window design

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1988-01-01

    On-orbit proximity operations (PROX-OPS) consist of all extravehicular activity (EVA) within 1 km of the space station. Because of the potentially large variety of PROX-OPS, very careful planning for space station windows is called for and must consider a great many human factors. The following topics are discussed: (1) basic window design philosophy and assumptions; (2) the concept of the local horizontal - local vertical on-orbit; (3) window linear dimensions; (4) selected anthropomorphic considerations; (5) displays and controls relative to windows; and (6) full window assembly replacement.

  12. Thermophotovoltaic Converter Design for Radioisotope Power Systems

    NASA Astrophysics Data System (ADS)

    Murray, Christopher S.; Crowley, Christopher J.; Murray, Susan; Elkouh, Nabil A.; Hill, Roger W.; Chubb, Donald E.

    2004-11-01

    The development of lightweight, efficient power for emerging NASA missions and recent advances in thermophotovoltaic (TPV) conversion technology have renewed interest in the possibility of combining radioisotope heat sources with photovoltaic energy conversion. Thermophotovoltaic power conversion uses advanced materials able to utilize a broader, spectrally tuned range of wavelengths. Spectral control, including the combination of emitter, TPV module, and filter, is key to high-efficiency operation. This paper summarizes the performance characteristics of monolithic integrated module (MIM) PV cells and arrays, tandem filters, and tungsten emitters fabricated for the present studies. The current, voltage, quantum efficiency, and diode efficiency of multi-junction 0.60 eV bandgap devices are presented for individual PV cells and strings of several cells. This paper discusses the design considerations for mechanical layout of PV cell arrays and integration with filters. The vacuum facility to be used to test these PV cell arrays is also described.

  13. Operator Station Design System - A computer aided design approach to work station layout

    NASA Technical Reports Server (NTRS)

    Lewis, J. L.

    1979-01-01

    The Operator Station Design System is resident in NASA's Johnson Space Center Spacecraft Design Division Performance Laboratory. It includes stand-alone minicomputer hardware and Panel Layout Automated Interactive Design and Crew Station Assessment of Reach software. The data base consists of the Shuttle Transportation System Orbiter Crew Compartment (in part), the Orbiter payload bay and remote manipulator (in part), and various anthropometric populations. The system is utilized to provide panel layouts, assess reach and vision, determine interference and fit problems early in the design phase, study design applications as a function of anthropometric and mission requirements, and to accomplish conceptual design to support advanced study efforts.

  14. Guide for Identifying and Converting High-Potential Petroleum Brownfield Sites to Alternative Fuel Stations

    SciTech Connect

    Johnson, C.; Hettinger, D.; Mosey, G.

    2011-05-01

    Former gasoline stations that are now classified as brownfields can be good sites to sell alternative fuels because they are in locations that are convenient to vehicles and they may be seeking a new source of income. However, their success as alternative fueling stations is highly dependent on location-specific criteria. First, this report outlines what these criteria are, how to prioritize them, and then applies that assessment framework to five of the most popular alternative fuels--electricity, natural gas, hydrogen, ethanol, and biodiesel. The second part of this report delves into the criteria and tools used to assess an alternative fuel retail site at the local level. It does this through two case studies of converting former gasoline stations in the Seattle-Eugene area into electric charge stations. The third part of this report addresses steps to be taken after the specific site has been selected. This includes choosing and installing the recharging equipment, which includes steps to take in the permitting process and key players to include.

  15. Habitability design elements for a space station

    NASA Technical Reports Server (NTRS)

    Dalton, M. C.

    1983-01-01

    Habitability in space refers to the components, characteristics, conditions, and design parameters that go beyond but include the basic life sustaining requirements. Elements of habitability covered include internal environment, architecture, mobility and restraint, food, clothing, personal hygiene, housekeeping, communications, and crew activities. All elements are interrelated and need to be treated as an overall discipline. Designing for a space station is similar to designing on earth but with 'space rules' instead of ground rules. It is concluded that some habitability problems require behavioral science solutions.

  16. Space station orbit design using dynamic programming

    NASA Astrophysics Data System (ADS)

    Lin, Kun-Peng; Luo, Ya-Zhong; Tang, Guo-Jin

    2013-08-01

    A space station orbit design mission is characterized by a long-duration and multi-step decision process. First, the long-duration design process is divided into multiple planning periods, each of which consists of five basic flight segments. Second, each planning period is modeled as a multi-step decision process, and the orbital altitude strategies of different flight segments have interaction effects on each other. Third, a dynamic programming method is used to optimize the total propellant consumption of a planning period while considering interaction effects. The step cost of each decision segment is the propellant for orbital-decay maintenance or lifting altitude, and is calculated by approximate analytical equations and combining a shooting iteration method. The proposed approach is demonstrated for a typical orbit design problem of a space station. The results show that the proposed approach can effectively optimize the design of altitude strategies, and can save considerable propellant consumption for the space station than previous public studies.

  17. Combustor design tool for a gas fired thermophotovoltaic energy converter

    SciTech Connect

    Lindler, K.W.; Harper, M.J.

    1995-07-01

    Recently, there has been a renewed interest in thermophotovoltaic (TPV) energy conversion. A TPV device converts radiant energy from a high temperature incandescent emitter directly into electricity by photovoltaic cells. The current Department of Energy sponsored research involves the design, construction and demonstration of a prototype TPV converter that uses a hydrocarbon fuel (such as natural gas) as the energy source. As the photovoltaic cells are designed to efficiently convert radiant energy at a prescribed wavelength, it is important that the temperature of the emitter be nearly constant over its entire surface. The US Naval Academy has been tasked with the development of a small emitter (with a high emissivity) that can be maintained at 1,756 K (2,700 F). This paper describes the computer spreadsheet model that was developed as a tool to be used for the design of the high temperature emitter.

  18. Combustor design tool for a gas fired thermophotovoltaic energy converter

    SciTech Connect

    Lindler, K.W.; Harper, M.J.

    1995-12-31

    Recently, there has been a renewed interest in thermophotovoltaic (TPV) energy conversion. A TPV device converts radiant energy from a high temperature incandescent emitter directly into electricity by photovoltaic cells. The current Department of Energy sponsored research involves the design, construction and demonstration of a prototype TPV converter that uses a hydrocarbon fuel (such as natural gas) as the energy source. As the photovoltaic cells are designed to efficiently convert radiant energy at a prescribed wavelength, it is important that the temperature of the emitter be nearly constant over its entire surface. The U. S. Naval Academy has been tasked with the development of a small emitter (with a high emissivity) that can be maintained at 1756 K (2700 F). This paper describes the computer spreadsheet model that was developed as a tool to be used for the design of the high temperature emitter.

  19. Space Station Freedom photovoltaic power module design status

    NASA Technical Reports Server (NTRS)

    Jimenez, Amador P.; Hoberecht, Mark A.

    1989-01-01

    Electric power generation for the Space Station Freedom will be provided by four photovoltaic (PV) power modules using silicon solar cells during phase I operation. Each PV power module requires two solar arrays with 32,800 solar cells generating 18.75 kW of dc power for a total of 75 kW. A portion of this power will be stored in nickel-hydrogen batteries for use during eclipse, and the balance will be processed and converted to 20 kHz ac power for distribution to end users through the power management and distribution system. The design incorporates an optimized thermal control system, pointing and tracking provision with the application of gimbals, and the use of orbital replacement units to achieve modularization. The design status of the PV power module, as derived from major trade studies, is discussed at hardware levels ranging from component to system. Details of the design are presented where appropriate.

  20. Space Station Freedom photovoltaic power module design status

    NASA Technical Reports Server (NTRS)

    Jimenez, Amador P.; Hoberecht, Mark A.

    1989-01-01

    Electric power generation for Space Station Freedom will be provided by four photovoltaic (PV) power modules using silicon solar cells during Phase 1 operation. Each PV power module requires two solar arrays with 32,800 solar cells generating 18.75 kW of dc power for a total of 75 kW. A portion of this power will be stored in nickel-hydrogen batteries for use during eclipse, and the balance will be processed and converted to 20 kHz ac power for distribution to end users through the power management and distribution system. The design incorporates an optimized thermal control system, pointing and tracking provision with the application of gimbals, and the use of orbital replacement units (ORU's) to achieve modularization. Design status of the PV power module, as derived from major trade studies, is discussed at hardware levels ranging from component to system. Details of the design are presented where appropriate.

  1. Design of Compact Multi-Megawatt Mode Converter

    SciTech Connect

    Dolgashev, V.A.; Tantawi, S.G.; Nantista, C.D.; /SLAC

    2006-03-21

    Experience gained during recent operation of high power 11.424 GHz rf sources for accelerators led to new, more strict requirements on system components. One of the basic components of such a system is a mode converter that transforms the rectangular waveguide mode into the TE{sub 01} mode in circular waveguide. With such a converter, it is possible to minimize the use of WR90 rectangular waveguide which was shown to be a weak part of the previous system at power levels higher than 100 MW and pulse lengths on the order of a microsecond. We used several methods to design a mode converter with extremely low parasitic mode conversion and compact size. These methods employ HFSS[4] and include multi-parameter searches, concurrent optimization with a mode-matching code Cascade[2], cascading of resulting S-matrices, and tolerance analysis using perturbation techniques. This report describes the design methods and presents results.

  2. Space Station body mounted radiator design

    NASA Technical Reports Server (NTRS)

    Fleming, M. L.; Duschatko, R. J.

    1987-01-01

    Consideration has been given to utilizing the external area of the Space Station common modules or resource nodes to provide heat rejection. A program was undertaken to define the best body mounted radiator design, to define and build a full size test article and to conduct testing to verify performance. Trade studies were conducted and a preferred design selected. The selected design employed high performance grooved heat pipes of an off-the-shelf design. Twenty panels, each about 1.2 m wide by 5.6 m long are installed on each module rejecting a total of about 12 kW. The radiators are interfaced with the module thermal control loop by use of a refrigerant 21 loop with an on-orbit operable disconnect at each panel. A one-panel test article has been designed and is currently being fabricated. Testing is scheduled to be conducted in June of 1987.

  3. Processing and circuit design enhance a data converter's radiation tolerance

    SciTech Connect

    Heuner, R.; Zazzu, V.; Pennisi, L.

    1988-12-01

    Rad-hard CMOS/SOS processing has been applied to a novel comparator-inverter circuit design to develop 6 and 8-bit parallel (flash) ADC (analog-to-digital converter) circuits featuring high-speed operation, low power consumption, and total-dose radiation tolerances up to 1 Mrad(Si).

  4. Aiding Design of Wave Energy Converters via Computational Simulations

    NASA Astrophysics Data System (ADS)

    Jebeli Aqdam, Hejar; Ahmadi, Babak; Raessi, Mehdi; Tootkaboni, Mazdak

    2015-11-01

    With the increasing interest in renewable energy sources, wave energy converters will continue to gain attention as a viable alternative to current electricity production methods. It is therefore crucial to develop computational tools for the design and analysis of wave energy converters. A successful design requires balance between the design performance and cost. Here an analytical solution is used for the approximate analysis of interactions between a flap-type wave energy converter (WEC) and waves. The method is verified using other flow solvers and experimental test cases. Then the model is used in conjunction with a powerful heuristic optimization engine, Charged System Search (CSS) to explore the WEC design space. CSS is inspired by charged particles behavior. It searches the design space by considering candidate answers as charged particles and moving them based on the Coulomb's laws of electrostatics and Newton's laws of motion to find the global optimum. Finally the impacts of changes in different design parameters on the power takeout of the superior WEC designs are investigated. National Science Foundation, CBET-1236462.

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

    NASA Technical Reports Server (NTRS)

    Haines, R. F.

    1975-01-01

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

  6. Test and evaluation of load converter topologies used in the Space Station Freedom Power Management and distribution DC test bed

    NASA Technical Reports Server (NTRS)

    Lebron, Ramon C.; Oliver, Angela C.; Bodi, Robert F.

    1991-01-01

    Power components hardware in support of the Space Station Freedom dc Electrical Power System were tested. One type of breadboard hardware tested is the dc Load Converter Unit, which constitutes the power interface between the electric power system and the actual load. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. Three load converters were tested: a series resonant converter, a series inductor switchmode converter, and a switching full-bridge forward converter. The topology, operation principles, and tests results are described, in general. A comparative analysis of the three units is given with respect to efficiency, regulation, short circuit behavior (protection), and transient characteristics.

  7. Test and evaluation of load converter topologies used in the Space Station Freedom power management and distribution dc test bed

    NASA Technical Reports Server (NTRS)

    Lebron, Ramon C.; Oliver, Angela C.; Bodi, Robert F.

    1991-01-01

    Power components hardware in support of the Space Station freedom dc Electric Power System were tested. One type of breadboard hardware tested is the dc Load Converter Unit, which constitutes the power interface between the electric power system and the actual load. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. Three load converters were tested: a series resonant converter, a series inductor switch-mode converter, and a switching full-bridge forward converter. The topology, operation principles, and test results are described, in general. A comparative analysis of the three units is given with respect to efficiency, regulation, short circuit behavior (protection), and transient characteristics.

  8. Design and evaluation of cellular power converter architectures

    NASA Astrophysics Data System (ADS)

    Perreault, David John

    Power electronic technology plays an important role in many energy conversion and storage applications, including machine drives, power supplies, frequency changers and UPS systems. Increases in performance and reductions in cost have been achieved through the development of higher performance power semiconductor devices and integrated control devices with increased functionality. Manufacturing techniques, however, have changed little. High power is typically achieved by paralleling multiple die in a sing!e package, producing the physical equivalent of a single large device. Consequently, both the device package and the converter in which the device is used continue to require large, complex mechanical structures, and relatively sophisticated heat transfer systems. An alternative to this approach is the use of a cellular power converter architecture, which is based upon the parallel connection of a large number of quasi-autonomous converters, called cells, each of which is designed for a fraction of the system rating. The cell rating is chosen such that single-die devices in inexpensive packages can be used, and the cell fabricated with an automated assembly process. The use of quasi-autonomous cells means that system performance is not compromised by the failure of a cell. This thesis explores the design of cellular converter architectures with the objective of achieving improvements in performance, reliability, and cost over conventional converter designs. New approaches are developed and experimentally verified for highly distributed control of cellular converters, including methods for ripple cancellation and current-sharing control. The performance of these techniques are quantified, and their dynamics are analyzed. Cell topologies suitable to the cellular architecture are investigated, and their use for systems in the 5-500 kVA range is explored. The design, construction, and experimental evaluation of a 6 kW cellular switched-mode rectifier is also addressed

  9. Practical design considerations for photovoltaic power station

    NASA Astrophysics Data System (ADS)

    Swanson, T. D.

    Aspects of photovoltaic (PV) technology are discussed along with generic PV design considerations, taking into account the resource sunlight, PV modules and their reliability, questions of PV system design, the support structure subsystem, and a power conditioning unit subsystem. A description is presented of two recent projects which demonstrate the translation of an idea into actual working PV systems. A privately financed project in Denton, Maryland, went on line in early December, 1982, and began providing power to the local utility grid. It represents the first intermediate size, grid-connected, privately financed power station in the U.S. Based on firm quotes, the actual cost of this system is about $13/W peak. The other project, called the PV Breeder, is an energy independent facility which utilizes solar power to make new solar cells. It is also the first large industrial structure completely powered by the sun.

  10. Conceptual design of a submerged power station

    SciTech Connect

    Herring, J.S.

    1992-08-01

    Providing safe and sustainable energy to the world`s increasing population will be one of the major challenges of the 21st century. At the INEL we are developing the concept of a passively safe submerged power station (SPS), shown. The reactor is located in the forward part of the vessel, while the turbine and generator are mounted in the middle section and the control and crew quarters are located at the opposite end of the vessel. The SPS would be operated in 20 to 100 m of water at a distance of 10 to 30 km from the shore and would generate 600 MWe. Power would be transmitted to shore by AC cables, similar to submarine cables in use today. The SPS would be manufactured in a central shipyard and towed or transported to its operational location. The reactor is designed to operate on a five-year cycle with a capacity factor of 70 percent, after which the station would be returned to a central facility for refueling and maintenance. Thus the SPS has the advantages of centralized fabrication and maintenance.

  11. Conceptual design of a submerged power station

    SciTech Connect

    Herring, J.S.

    1992-01-01

    Providing safe and sustainable energy to the world's increasing population will be one of the major challenges of the 21st century. At the INEL we are developing the concept of a passively safe submerged power station (SPS), shown. The reactor is located in the forward part of the vessel, while the turbine and generator are mounted in the middle section and the control and crew quarters are located at the opposite end of the vessel. The SPS would be operated in 20 to 100 m of water at a distance of 10 to 30 km from the shore and would generate 600 MWe. Power would be transmitted to shore by AC cables, similar to submarine cables in use today. The SPS would be manufactured in a central shipyard and towed or transported to its operational location. The reactor is designed to operate on a five-year cycle with a capacity factor of 70 percent, after which the station would be returned to a central facility for refueling and maintenance. Thus the SPS has the advantages of centralized fabrication and maintenance.

  12. Development, Evaluation, and Design Applications of an AMTEC Converter Model

    NASA Astrophysics Data System (ADS)

    Spence, Cliff A.; Schuller, Michael; Lalk, Tom R.

    2003-01-01

    Issues associated with the development of an alkali metal thermal-to-electric conversion (AMTEC) converter model that serves as an effective design tool were investigated. The requirements and performance prediction equations for the model were evaluated, and a modeling methodology was established. It was determined by defining the requirements and equations for the model and establishing a methodology that Thermal Desktop, a recently improved finite-difference software package, could be used to develop a model that serves as an effective design tool. Implementing the methodology within Thermal Desktop provides stability, high resolution, modular construction, easy-to-use interfaces, and modeling flexibility.

  13. Severe Accident Test Station Design Document

    SciTech Connect

    Snead, Mary A.; Yan, Yong; Howell, Michael; Keiser, James R.; Terrani, Kurt A.

    2015-09-01

    The purpose of the ORNL severe accident test station (SATS) is to provide a platform for evaluation of advanced fuels under projected beyond design basis accident (BDBA) conditions. The SATS delivers the capability to map the behavior of advanced fuels concepts under accident scenarios across various temperature and pressure profiles, steam and steam-hydrogen gas mixtures, and thermal shock. The overall facility will include parallel capabilities for examination of fuels and irradiated materials (in-cell) and non-irradiated materials (out-of-cell) at BDBA conditions as well as design basis accident (DBA) or loss of coolant accident (LOCA) conditions. Also, a supporting analytical infrastructure to provide the data-needs for the fuel-modeling components of the Fuel Cycle Research and Development (FCRD) program will be put in place in a parallel manner. This design report contains the information for the first, second and third phases of design and construction of the SATS. The first phase consisted of the design and construction of an out-of-cell BDBA module intended for examination of non-irradiated materials. The second phase of this work was to construct the BDBA in-cell module to test irradiated fuels and materials as well as the module for DBA (i.e. LOCA) testing out-of-cell, The third phase was to build the in-cell DBA module. The details of the design constraints and requirements for the in-cell facility have been closely captured during the deployment of the out-of-cell SATS modules to ensure effective future implementation of the in-cell modules.

  14. International Space Station Crew Restraint Design

    NASA Technical Reports Server (NTRS)

    Whitmore, M.; Norris, L.; Holden, K.

    2005-01-01

    With permanent human presence onboard the International Space Station (ISS), crews will be living and working in microgravity, dealing with the challenges of a weightless environment. In addition, the confined nature of the spacecraft environment results in ergonomic challenges such as limited visibility and access to the activity areas, as well as prolonged periods of unnatural postures. Without optimum restraints, crewmembers may be handicapped for performing some of the on-orbit tasks. Currently, many of the tasks on ISS are performed with the crew restrained merely by hooking their arms or toes around handrails to steady themselves. This is adequate for some tasks, but not all. There have been some reports of discomfort/calluses on the top of the toes. In addition, this type of restraint is simply insufficient for tasks that require a large degree of stability. Glovebox design is a good example of a confined workstation concept requiring stability for successful use. They are widely used in industry, university, and government laboratories, as well as in the space environment, and are known to cause postural limitations and visual restrictions. Although there are numerous guidelines pertaining to ventilation, seals, and glove attachment, most of the data have been gathered in a 1-g environment, or are from studies that were conducted prior to the early 1980 s. Little is known about how best to restrain a crewmember using a glovebox in microgravity. In 2004, The Usability Testing and Analysis Facility (UTAF) at the NASA Johnson Space Center completed development/evaluation of several design concepts for crew restraints to meet the various needs outlined above. Restraints were designed for general purpose use, for teleoperation (Robonaut) and for use with the Life Sciences Glovebox. All design efforts followed a human factors engineering design lifecycle, beginning with identification of requirements followed by an iterative prototype/test cycle. Anthropometric

  15. A three-phase series-parallel resonant converter -- analysis, design, simulation and experimental results

    SciTech Connect

    Bhat, A.K.S.; Zheng, L.

    1995-12-31

    A three-phase dc-to-dc series-parallel resonant converter is proposed and its operating modes for 180{degree} wide gating pulse scheme are explained. A detailed analysis of the converter using constant current model and Fourier series approach is presented. Based on the analysis, design curves are obtained and a design example of 1 kW converter is given. SPICE simulation results for the designed converter and experimental results for a 500 W converter are presented to verify the performance of the proposed converter for varying load conditions. The converter operates in lagging PF mode for the entire load range and requires a narrow variation in switching frequency.

  16. An approach to design knowledge capture for the space station

    NASA Technical Reports Server (NTRS)

    Wechsler, D. B.; Crouse, K. R.

    1986-01-01

    The design of NASA's space station has begun. During the design cycle, and after activation of the space station, the reoccurring need will exist to access not only designs, but also deeper knowledge about the designs, which is only hinted in the design definition. Areas benefiting from this knowledge include training, fault management, and onboard automation. NASA's Artificial Intelligence Office at Johnson Space Center and The MITRE Corporation have conceptualized an approach for capture and storage of design knowledge.

  17. Transportation node space station conceptual design

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A number of recent studies have addressed the problem of a transportation node space station. How things would change or what addition facilities would be needed to support a major lunar or Mars initiative is a much often asked question. The support of a lunar base, requiring stacks on the order of 200 metric tons each to land 25 m tons on the lunar surface with reusable vehicles is addressed. The problem of maintaining and reusing large single stage Orbit Transfer Vehicles (OTVs) and single stage lander/launchers in space are examined. The required people and equipment needed, to maintain these vehicles are only vaguely known at present. The people and equipment needed depend on how well the OTV and lander/launcher can be designed for easy reuse. Since the OTV and lander/launcher are only conceptually defined at present, the real maintenance and refurbishment requirements are unobtainable. An estimate of what is needed, based on previous studies and obvious requirements was therefore made. An attempt was made to err on the conservative side.

  18. Zinc Oxide Surge Arresters and HVDC 125kV-upgrade 500kV Converter Stations

    NASA Astrophysics Data System (ADS)

    Shirakawa, Shingo; Kobayashi, Takayuki; Matsushita, Yoshinao; Sakai, Takehisa; Suzuki, Hironori; Ozaki, Yuzo

    Gapless Metal (Zinc) Oxide Surge Arresters for a.c. systems contribute to the insulation co-ordination based on the suppression of lightning surges and switching surges. These gapless metal oxide surge arresters using ZnO elements are effective to HVDC systems. This paper describes basic characteristics of ZnO (zinc oxide) elements for d.c. systems and applications of gapless surge arresters to HVDC 125kV frequency converters, HVDC 250kV, upgrade HVDC 500kV converter stations, and HVDC 500kV cables of Japan through the experience of developments and applications of gapless metal oxide surge arresters.

  19. A design optimization process for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Chamberlain, Robert G.; Fox, George; Duquette, William H.

    1990-01-01

    The Space Station Freedom Program is used to develop and implement a process for design optimization. Because the relative worth of arbitrary design concepts cannot be assessed directly, comparisons must be based on designs that provide the same performance from the point of view of station users; such designs can be compared in terms of life cycle cost. Since the technology required to produce a space station is widely dispersed, a decentralized optimization process is essential. A formulation of the optimization process is provided and the mathematical models designed to facilitate its implementation are described.

  20. Design and Analysis of the Main AC/DC Converter System for ITER

    NASA Astrophysics Data System (ADS)

    Sheng, Zhicai; Xu, Liuwei; Fu, Peng

    2012-04-01

    A design of the main AC/DC converter system for ITER is described and the configuration of the main AC/DC converters is presented. To reduce the reactive power absorbed from the converter units, the main AC/DC converters are designed to be series-connected and work in a sequential mode. The structure of the regulator of the converter system is described. A simulation model was built up for the PSCAD/EMTDC code, and the design was validated accordingly. Harmonic analysis and reactive power calculation of the converters units are presented. The results reveal the advantage of sequential control in reducing reactive power and harmonics.

  1. Apollo experience report: Crew station integration. Volume 1: Crew station design and development

    NASA Technical Reports Server (NTRS)

    Allen, L. D.; Nussman, D. A.

    1976-01-01

    An overview of the evolution of the design and development of the Apollo command module and lunar module crew stations is given, with emphasis placed on the period from 1964 to 1969. The organizational planning, engineering techniques, and documentation involved are described, and a detailed chronology of the meetings, reviews, and exercises is presented. Crew station anomalies for the Apollo 7 to 11 missions are discussed, and recommendations for the solution of recurring problems of crew station acoustics, instrument glass failure, and caution and warning system performance are presented. Photographs of the various crew station configurations are also provided.

  2. Converting Limbo Lands to Energy-Generating Stations: Renewable Energy Technologies on Underused, Formerly Contaminated Sites

    SciTech Connect

    Mosey, G.; Heimiller, D.; Dahle, D.; Vimmerstedt, L.; Brady-Sabeff, L.

    2007-10-01

    This report addresses the potential for using 'Limbo Lands' (underused, formerly contaminated sites, landfills, brownfields, abandoned mine lands, etc. ) as sites for renewable energy generating stations.

  3. Design, status and first operations of the spallation neutron source polyphase resonant converter modulator system

    SciTech Connect

    Reass, W. A.; Apgar, S. E.; Baca, D. M.; Doss, James D.; Gonzales, J.; Gribble, R. F.; Hardek, T. W.; Lynch, M. T.; Rees, D. E.; Tallerico, P. J.; Trujillo, P. B.; Anderson, D. E.; Heidenreich, D. A.; Hicks, J. D.; Leontiev, V. N.

    2003-01-01

    The Spallation Neutron Source (SNS) is a new 1.4 MW average power beam, 1 GeV accelerator being built at Oak Ridge National Laboratory. The accelerator requires 15 converter-modulator stations each providing between 9 and 11 MW pulses with up to a 1 .I MW average power. The converter-modulator can be described as a resonant 20 kHz polyphase boost inverter. Each converter modulator derives its buss voltage from a standard substation cast-core transformer. Each substation is followed by an SCR pre-regulator to accommodate voltage changes from no load to full load, in addition to providing a soft-start function. Energy storage is provided by self-clearing metallized hazy polypropylene traction capacitors. These capacitors do not fail short, but clear any internal anomaly. Three 'H-Bridge' IGBT transistor networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are time-gated to generate the desired klystron pulse width. Pulse width modulation of the individual 20 lcHz pulses is utilized to provide regulated output waveforms with DSP based adaptive feedforward and feedback techniques. The boost transformer design utilizes nanocrystalline alloy that provides low core loss at design flux levels and switching frequencies. Capacitors are used on the transformer secondary networks to resonate the leakage inductance. The transformers are wound for a specific leakage inductance, not turns ratio. This design technique generates multiple secondary volts per turn as compared to the primary. With the appropriate tuning conditions, switching losses are minimized. The resonant topology has the added benefit of being deQed in a klystron fault condition, with little energy deposited in the arc. This obviates the need of crowbars or other related networks. A review of these design parameters, operational performance, production status, and OWL installation and performance to date will be presented.

  4. Telescope Array Radar (TARA) Remote Station Design and Development

    NASA Astrophysics Data System (ADS)

    Kunwar, Samridha

    2014-03-01

    The TARA project is a novel attempt utilizing a bi - static radar configuration in conjunction with a set of conventional cosmic ray detectors in the low - noise environment in Millard County, Utah, to detect Ultra - High Energy Cosmic Ray induced Extensive Air Showers. We present the design and development of the remote radar receiver system using a technique where the Doppler-shifted reflected signal off of the ionization trail from the cosmic ray is de - chirped. The approach is based on an analog frequency mixing technique whereby the input signal is mixed with a delayed copy of itself i.e s (t) ⊗ s (t - τ) , resulting in a beat frequency, f, which is proportional to the delay time multiplied by the cosmic ray-induced RF chirp rate. With appropriate filtering, the problem of chirp detection is ultimately reduced to that of detecting the down - converted monotone. In contrast to conventional signal processing via digital matched filtering, this is a mostly analog data acquisition system and has lower power consumption at a cost which is also comparatively inexpensive. The remote station is also subject to less radio interference, and adds stereoscopic measurement capabilities which allows unique determination of cosmic ray geometry and core location.

  5. Designing a Reference Station for the Information Age.

    ERIC Educational Resources Information Center

    Becket, Margaret; Smith, Henry Bradford

    1986-01-01

    Relates experiences of University of Rochester's main library during complete renovation of the central reference department including the addition of a full-service reference station. Topics covered include planning the reference station, solutions to seven design requirements, increase in staffing and reference questions after one year, and…

  6. Converting Limbo Lands to Energy-Generating Stations: Renewable Energy Technologies on Underused, Formerly Contaminated Sites

    EPA Science Inventory

    This report addresses the potential for using "Limbo Lands" as sites for renewable energy generating stations. Limbo Lands are considered as underused, formerly contaminated sites, and include former Superfund sites, landfills, brownfields, abandoned mine lands, former industrial...

  7. DESIGN NOTE: A compact catalytic converter for the production of para-hydrogen

    NASA Astrophysics Data System (ADS)

    Juarez, A. M.; Cubric, D.; King, G. C.

    2002-05-01

    The design and operation of a compact converter to produce a constant flow of para-hydrogen from normal hydrogen is described. The converter features a paramagnetic compound (nickel sulfate) that catalyses the conversion of ortho- to para-hydrogen at temperatures of 14-21 K. The converter has been tested by measuring rotationally resolved photoelectron spectra in the para-hydrogen produced. The percentage of the para-hydrogen species in the converted gas was determined to be >97%.

  8. Design and analysis of VCSEL based twodimension wavelength converter.

    PubMed

    Liu, H; Shum, P; Kao, M

    2003-07-14

    A novel two-dimensional vertical cavity surface emission laser (VCSEL) based wavelength converter is proposed. We developed a twodimensional transmission line laser model (TLLM) to analyze the proposed wavelength converter. This model takes into account Bragg reflectors by using the modified connecting matrix. Therefore, accurate and efficient modeling of the VCSEL structure is achieved. Extinction ratio of the output signal is investigated by considering input signal power, wavelength, facet reflectivity and cavity diameter. PMID:19466044

  9. Design of a DC Busbar for the ITER PF Converter

    NASA Astrophysics Data System (ADS)

    Guo, Bin; Song, Zhiquan; Xu, Liuwei; Zhang, Ming; Li, Jinchao; Jiang, Li; Fu, Peng; Wang, Min; Dong, Lin

    2014-04-01

    The DC busbar is an important component for the ITER PF converter module to connect the converter and the reactor. This paper analyzes different cross-sections and different thermodynamic properties under natural-cooling and water-cooling conditions, and simulation is carried out by the software of the finite element method (FEM). The result of the analysis shows that the water-cooling method is the better choice for the DC busbar.

  10. Design of the space station Freedom power system

    SciTech Connect

    Thomas, R.L. . Lewis Research Center); Hallinan, G.J. . Rocketdyne Div.)

    1990-01-01

    The design of space station freedom's electric power system is reviewed highlighting the key design goals of performance, low cost, reliability and safety. Trade study results are discussed which illustrate the competing factors responsible for many of the more important design decisions.

  11. A three-phase series-parallel resonant converter -- analysis, design, simulation, and experimental results

    SciTech Connect

    Bhat, A.K.S.; Zheng, R.L.

    1996-07-01

    A three-phase dc-to-dc series-parallel resonant converter is proposed /and its operating modes for a 180{degree} wide gating pulse scheme are explained. A detailed analysis of the converter using a constant current model and the Fourier series approach is presented. Based on the analysis, design curves are obtained and a design example of a 1-kW converter is given. SPICE simulation results for the designed converter and experimental results for a 500-W converter are presented to verify the performance of the proposed converter for varying load conditions. The converter operates in lagging power factor (PF) mode for the entire load range and requires a narrow variation in switching frequency, to adequately regulate the output power.

  12. Hybrid Rocket Experiment Station for Capstone Design

    NASA Technical Reports Server (NTRS)

    Conley, Edgar; Hull, Bethanne J.

    2012-01-01

    Portable hybrid rocket motors and test stands can be seen in many papers but none have been reported on the design or instrumentation at such a small magnitude. The design of this hybrid rocket and test stand is to be small and portable (suitcase size). This basic apparatus will be used for demonstrations in rocket propulsion. The design had to include all of the needed hardware to operate the hybrid rocket unit (with the exception of the external Oxygen tank). The design of this project includes making the correlation between the rocket's thrust and its size, the appropriate transducers (physical size, resolution, range, and cost), compatability with a laptop analog card, the ease of setup, and its portability.

  13. Genesis Halo Orbit Station Keeping Design

    NASA Technical Reports Server (NTRS)

    Lo, M.; Williams, K.; Wilson, R.; Howell, K.; Barden, B.

    2000-01-01

    As the fifth mission of NASA's Directory Program, Genesis is designed to collect solar wind samples for approximately two years in a halo orbit near the Sun-Earth L(sub 1) Lagrange point for return to the Earth.

  14. Design of photovoltaic central power station concentrator array

    SciTech Connect

    Not Available

    1984-02-01

    A design for a photovoltaic central power station using tracking concentrators has been developed. The 100 MW plant is assumed to be located adjacent to the Saguaro Power Station of Arizona Public Service. The design assumes an advanced Martin Marietta two-axis tracking fresnel lens concentrator. The concentrators are arrayed in 5 MW subfields, each with its own power conditioning unit. The photovoltaic plant output is connected to the existing 115 kV switchyard. The site specific design allows detailed cost estimates for engineering, site preparation, and installation. Collector and power conditioning costs have been treated parametrically.

  15. Design of deployable-truss masts for Space Station

    NASA Technical Reports Server (NTRS)

    Bowden, Mary; Benton, Max

    1993-01-01

    This paper presents an overview of three deployable-truss designs that were considered for use on Space Station Freedom to deploy the solar array wings. The first design chosen early in the program was a nut-deployed coilable longeron mast which has the advantage of being lightweight and reliable, with considerable flight history. Subsequently, because of the restructure of Space Station, a second design was chosen: a lanyard-deployed FASTMast (Folding Articulated Square Truss Mast), which has improved strength and redundancy characteristics for a given stowed volume. After further definition of the load requirements during deployment, however, it became necessary to modify the deployment system, resulting in the third mast design for space station solar arrays: a nut-deployed FASTMast, which was ultimately selected to provide increased stiffness and strength during deployment. This paper presents a brief review of these mast designs and their associated deployment systems, emphasizing the trade-offs involved in selecting between them. In addition, some innovative features of the FASTMast design as it stands currently for Space Station are described, and a brief review of the test program that is underway to qualify this design for flight is included.

  16. Space station electric power system requirements and design

    NASA Technical Reports Server (NTRS)

    Teren, Fred

    1987-01-01

    An overview of the conceptual definition and design of the space station Electric Power System (EPS) is given. Responsibilities for the design and development of the EPS are defined. The EPS requirements are listed and discussed, including average and peak power requirements, contingency requirements, and fault tolerance. The most significant Phase B trade study results are summarized, and the design selections and rationale are given. Finally, the power management and distribution system architecture is presented.

  17. Optimum Design of CMOS DC-DC Converter for Mobile Applications

    NASA Astrophysics Data System (ADS)

    Katayama, Yasushi; Edo, Masaharu; Denta, Toshio; Kawashima, Tetsuya; Ninomiya, Tamotsu

    In recent years, low output power CMOS DC-DC converters which integrate power stage MOSFETs and a PWM controller using CMOS process have been used in many mobile applications. In this paper, we propose the calculation method of CMOS DC-DC converter efficiency and report optimum design of CMOS DC-DC converter based on this method. By this method, converter efficiencies are directly calculated from converter specifications, dimensions of power stage MOSFET and device parameters. Therefore, this method can be used for optimization of CMOS DC-DC converter design, such as dimensions of power stage MOSFET and switching frequency. The efficiency calculated by the proposed method agrees well with the experimental results.

  18. Integrated Station Executive requirements and systems design approach

    NASA Technical Reports Server (NTRS)

    Berger, Eugene L.; Morris, C. Doug

    1992-01-01

    The Avionics Office of the Space Station Projects Office at Johnson Space Center (JSC) is working to define and integrate end-to-end requirements for the Space Station Freedom Program (SSFP) space-ground operations. As part of these efforts, the project office has had the MITRE Corporation perform assessments and analyses in areas where they had particular concern. These areas include the changing concepts for test methodologies, the operation and performance of the communication protocols, end-to-end network management, and the Master Objects Data Base (MODB). Since the recent restructure of the space station design, a new software application, the Integrated Station Executive (ISE), has been established. This application is to act as an executive agent along with the crew and ground controllers, while replacing (or absorbing) many of the system management functions that required a home when distributed element management was eliminated. This document summarizes the current state of the ISE requirements and assesses the characteristics of the current design. MITRE's goals in this assessment and analysis is twofold: first, identify any internal inconsistencies in either the requirements or in the current design; and second, to examine the applicability of the Open System Interconnection (OSI) management standards. Inasmuch as the ISE has been defined as the executive or operations manager application within the integrated avionics of the space station, special attention is given to adapting OSI management for the specification of the ISE functions.

  19. Space Station Freedom pressurized element interior design process

    NASA Technical Reports Server (NTRS)

    Hopson, George D.; Aaron, John; Grant, Richard L.

    1990-01-01

    The process used to develop the on-orbit working and living environment of the Space Station Freedom has some very unique constraints and conditions to satisfy. The goal is to provide maximum efficiency and utilization of the available space, in on-orbit, zero G conditions that establishes a comfortable, productive, and safe working environment for the crew. The Space Station Freedom on-orbit living and working space can be divided into support for three major functions: (1) operations, maintenance, and management of the station; (2) conduct of experiments, both directly in the laboratories and remotely for experiments outside the pressurized environment; and (3) crew related functions for food preparation, housekeeping, storage, personal hygiene, health maintenance, zero G environment conditioning, and individual privacy, and rest. The process used to implement these functions, the major requirements driving the design, unique considerations and constraints that influence the design, and summaries of the analysis performed to establish the current configurations are described. Sketches and pictures showing the layout and internal arrangement of the Nodes, U.S. Laboratory and Habitation modules identify the current design relationships of the common and unique station housekeeping subsystems. The crew facilities, work stations, food preparation and eating areas (galley and wardroom), and exercise/health maintenance configurations, waste management and personal hygiene area configuration are shown. U.S. Laboratory experiment facilities and maintenance work areas planned to support the wide variety and mixtures of life science and materials processing payloads are described.

  20. Integrated Station Executive requirements and systems design approach

    NASA Astrophysics Data System (ADS)

    Berger, Eugene L.; Morris, C. Doug

    1992-11-01

    The Avionics Office of the Space Station Projects Office at Johnson Space Center (JSC) is working to define and integrate end-to-end requirements for the Space Station Freedom Program (SSFP) space-ground operations. As part of these efforts, the project office has had the MITRE Corporation perform assessments and analyses in areas where they had particular concern. These areas include the changing concepts for test methodologies, the operation and performance of the communication protocols, end-to-end network management, and the Master Objects Data Base (MODB). Since the recent restructure of the space station design, a new software application, the Integrated Station Executive (ISE), has been established. This application is to act as an executive agent along with the crew and ground controllers, while replacing (or absorbing) many of the system management functions that required a home when distributed element management was eliminated. This document summarizes the current state of the ISE requirements and assesses the characteristics of the current design. MITRE's goals in this assessment and analysis is twofold: first, identify any internal inconsistencies in either the requirements or in the current design; and second, to examine the applicability of the Open System Interconnection (OSI) management standards. Inasmuch as the ISE has been defined as the executive or operations manager application within the integrated avionics of the space station, special attention is given to adapting OSI management for the specification of the ISE functions.

  1. Space station proximity operations windows: Human factors design guidelines

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1987-01-01

    Proximity operations refers to all activities outside the Space Station which take place within a 1-km radius. Since there will be a large number of different operations involving manned and unmanned vehicles, single- and multiperson crews, automated and manually controlled flight, a wide variety of cargo, and construction/repair activities, accurate and continuous human monitoring of these operations from a specially designed control station on Space Station will be required. Total situational awareness will be required. This paper presents numerous human factors design guidelines and related background information for control windows which will support proximity operations. Separate sections deal with natural and artificial illumination geometry; all basic rendezvous vector approaches; window field-of-view requirements; window size; shape and placement criteria; window optical characteristics as they relate to human perception; maintenance and protection issues; and a comprehensive review of windows installed on U.S. and U.S.S.R. manned vehicles.

  2. Design of a base station for MEMS CCR localization in an optical sensor network.

    PubMed

    Park, Chan Gook; Jeon, Hyun Cheol; Kim, Hyoun Jin; Kim, Jae Yoon

    2014-01-01

    This paper introduces a design and implementation of a base station, capable of positioning sensor nodes using an optical scheme. The base station consists of a pulse laser module, optical detectors and beam splitter, which are mounted on a rotation-stage, and a Time to Digital Converter (TDC). The optical pulse signal transmitted to the sensor node with a Corner Cube Retro-reflector (CCR) is reflected to the base station, and the Time of Flight (ToF) data can be obtained from the two detectors. With the angle and flight time data, the position of the sensor node can be calculated. The performance of the system is evaluated by using a commercial CCR. The sensor nodes are placed at different angles from the base station and scanned using the laser. We analyze the node position error caused by the rotation and propose error compensation methods, namely the outlier sample exception and decreasing the confidence factor steadily using the recursive least square (RLS) methods. Based on the commercial CCR results, the MEMS CCR is also tested to demonstrate the compatibility between the base station and the proposed methods. The result shows that the localization performance of the system can be enhanced with the proposed compensation method using the MEMS CCR. PMID:24815681

  3. Design of a Base Station for MEMS CCR Localization in an Optical Sensor Network

    PubMed Central

    Park, Chan Gook; Jeon, Hyun Cheol; Kim, Hyoun Jin; Kim, Jae Yoon

    2014-01-01

    This paper introduces a design and implementation of a base station, capable of positioning sensor nodes using an optical scheme. The base station consists of a pulse laser module, optical detectors and beam splitter, which are mounted on a rotation-stage, and a Time to Digital Converter (TDC). The optical pulse signal transmitted to the sensor node with a Corner Cube Retro-reflector (CCR) is reflected to the base station, and the Time of Flight (ToF) data can be obtained from the two detectors. With the angle and flight time data, the position of the sensor node can be calculated. The performance of the system is evaluated by using a commercial CCR. The sensor nodes are placed at different angles from the base station and scanned using the laser. We analyze the node position error caused by the rotation and propose error compensation methods, namely the outlier sample exception and decreasing the confidence factor steadily using the recursive least square (RLS) methods. Based on the commercial CCR results, the MEMS CCR is also tested to demonstrate the compatibility between the base station and the proposed methods. The result shows that the localization performance of the system can be enhanced with the proposed compensation method using the MEMS CCR. PMID:24815681

  4. Optimum Design of LLC Resonant Converter using Inductance Ratio (Lm/Lr)

    NASA Astrophysics Data System (ADS)

    Palle, Kowstubha; Krishnaveni, K.; Ramesh Reddy, Kolli

    2016-07-01

    The main benefits of LLC resonant dc/dc converter over conventional series and parallel resonant converters are its light load regulation, less circulating currents, larger bandwidth for zero voltage switching, and less tuning of switching frequency for controlled output. An unique analytical tool, called fundamental harmonic approximation with peak gain adjustment is used for designing the converter. In this paper, an optimum design of the converter is proposed by considering three different design criterions with different values of inductance ratio (Lm/Lr) to achieve good efficiency at high input voltage. The optimum design includes the analysis in operating range, switching frequency range, primary side losses of a switch and stability. The analysis is carried out with simulation using the software tools like MATLAB and PSIM. The performance of the optimized design is demonstrated for a design specification of 12 V, 5 A output operating with an input voltage range of 300-400 V using FSFR 2100 IC of Texas instruments.

  5. Space Station external thermal control system design and operational overview

    NASA Technical Reports Server (NTRS)

    Raetz, John; Dominick, Jeff

    1992-01-01

    The driving design requirements and resulting design characteristics for a two-phase ammonia system of the Space Shuttle are reviewed with particular attention given to operational and station assembly issues related to system activation and steady-state operation. Design is described at an overall system level and an orbit replaceable unit level. It is concluded that a system flow network must be designed and ammonia pressures must be controlled to acquire waste heat efficiently from all contributing heat sources at a controlled temperature.

  6. Preliminary design of the Space Station internal thermal control system

    NASA Technical Reports Server (NTRS)

    Herrin, Mark T.; Patterson, David W.; Turner, Larry D.

    1987-01-01

    The baseline preliminary design configuration of the Internal Thermal Control system (ITCS) of the U.S. Space Station pressurized elements (i.e., the Habitation and U.S. Laboratory modules, pressurized logistics carrier, and resources nodes) is defined. The ITCS is composed of both active and passive components. The subsystems which comprise the ITCS are identified and their functional descriptions are provided. The significant trades and analyses, which were performed during Phase B (i.e., the preliminary design phase) that resulted in the design described herein, are discussed. The ITCS interfaces with the station's central Heat Rejection and Transport System (HRTS), other systems, and externally attached pressurized payloads are described. Requirements on the ITCS with regard to redundancy and experiment support are also addressed.

  7. Design, fabrication, and testing of an external fuel (UO2), full-length thermionic converter

    NASA Technical Reports Server (NTRS)

    Schock, A.; Raab, B.

    1971-01-01

    The development of a full-length external-fuel thermionic converter for in-pile testing is described. The development program includes out-of-pile performance testing of the fully fueled-converter, using RF-induction heating, before its installation in the in-pile test capsule. The external-fuel converter is cylindrical in shape, and consists of an inner, centrally cooled collector, and an outer emitter surrounded by nuclear fuel. The term full-length denotes that the converter is long enough to extend over the full height of the reactor core. Thus, the converter is not a scaled-down test device, but a full-scale fuel element of the thermionic reactor. The external-fuel converter concept permits a number of different design options, particularly with respect to the fuel composition and shape, and the collector cooling arrangement. The converter described was developed for the Jet Propulsion Laboratory, and is based on their concept for a thermionic reactor with uninsulated collector cooling as previously described. The converter is double-ended, with through-flow cooling, and with ceramic seals and emitter and collector power take-offs at both ends. The design uses a revolver-shaped tungsten emitter body, with the central emitter hole surrounded by six peripheral fuel holes loaded with cylindrical UO2 pellets.

  8. QMI: Rising to the Space Station Design Challenge

    NASA Astrophysics Data System (ADS)

    Carswell, W. E.; Farmer, J.; Coppens, C.; Breeding, S.; Rose, F.

    2002-01-01

    The Quench Module Insert (QMI) materials processing furnace is being designed to operate for 8000 hours over four years on the International Space Station as part of the first Materials Science Research Rack of the Materials Science Research Facility. The Bridgman-type furnace is being built for the directional solidification processing of metals and alloys in the microgravity environment of space. Most notably it will be used for processing aluminum and related alloys. Designing for the space station environment presents intriguing design challenges in the form of a ten-year life requirement coupled with both limited opportunities for maintenance and resource constraints in the form of limited power and space. The long life requirement has driven the design of several features in the furnace, including the design of the heater core, the selection and placement of the thermocouples, overall performance monitoring, and the design of the chill block. The power and space limitations have been addressed through a compact furnace design using efficient vacuum insulation. Details on these design features, as well as development test performance results to date, are presented.

  9. QMI: Rising to the Space Station Design Challenge

    NASA Technical Reports Server (NTRS)

    Carswell, W. E.; Farmer, J.; Coppens, C.; Breeding, S.; Rose, F.; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    The Quench Module Insert (QMI) materials processing furnace is being designed to operate for 8000 hours over four years on the International Space Station (ISS) as part of the first Materials Science Research Rack (MSRR-1) of the Materials Science Research Facility (MSRF). The Bridgman-type furnace is being built for the directional solidification processing of metals and alloys in the microgravity environment of space. Most notably it will be used for processing aluminum and related alloys. Designing for the space station environment presents intriguing design challenges in the form of a ten-year life requirement coupled with both limited opportunities for maintenance and resource constraints in the form of limited power and space. The long life requirement has driven the design of several features in the furnace, including the design of the heater core, the selection and placement of the thermocouples, overall performance monitoring, and the design of the chill block. The power and space limitations have been addressed through a compact furnace design using efficient vacuum insulation. Details on these design features, as well as development test performance results to date, are presented.

  10. Space Station Freedom ECLSS design configuration - A post restructure update

    NASA Technical Reports Server (NTRS)

    Bacskay, Allen S.; Dalee, Robert C.

    1991-01-01

    The Space Station Freedom Program (SSFP) has undergone major design changes within the last year due to reduced budget appropriations imposed by Congress. This paper outlines the impacts of the design changes on the Environmental Control and Life Support System (ECLSS), with emphasis on the system aspects of the ECLSS. Brief descriptions of design impacts to all six ECLSS subsystems are provided in addition to interactions with other distributed systems such as Data Management, Electrical Power, and Man Systems. The assembly sequence for SSF is addressed with emphasis on key flights with respect to the ECLSS.

  11. Design of a resistojet for Space Station Freedom

    NASA Astrophysics Data System (ADS)

    Garza, Jose; Reisman, Jill; Tapia, Jose; Wright, Anthony

    1993-05-01

    In the mid 1990's, NASA will begin assembly of Space Station Freedom, a permanent outpost in a low-earth orbit. For the station to remain in that orbit, an altitude control system must be developed to resist the effects of atmospheric drag. One system being considered by NASA is called a resistojet, and it uses highly pressurized waste gases heated by electrical resistance to provide thrust on the order of 1 Newton. An additional function of the resistojet is to vent waste gases used by the station and its inhabitants. This report focuses on resolving the issues of system performance, flow and heater control, and materials selection and designing test procedures to resolve, by experimentation, any remaining issues. The conceptual model of the resistojet consists of a shell wrapped by a resistive coil with gases flowing internally through the tube with additional components such as regulators, transducers, and thermocouples. For system performance, the major parameters were calculated from the desired thrust range, the pressure within the resistojet and the cold flow mode of operation; waste gases were analyzed at 100 percent capacity and between 58.95 kPa and 552 kPa. The design team found that any ventilation under all conditions would produce thrust, and therefore, it was decided to limit the design of the ventilation function. The design team proceeded with a simplified model to determine the nozzle throat diameter and chamber diameter.

  12. Design of a resistojet for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Garza, Jose; Reisman, Jill; Tapia, Jose; Wright, Anthony

    1993-01-01

    In the mid 1990's, NASA will begin assembly of Space Station Freedom, a permanent outpost in a low-earth orbit. For the station to remain in that orbit, an altitude control system must be developed to resist the effects of atmospheric drag. One system being considered by NASA is called a resistojet, and it uses highly pressurized waste gases heated by electrical resistance to provide thrust on the order of 1 Newton. An additional function of the resistojet is to vent waste gases used by the station and its inhabitants. This report focuses on resolving the issues of system performance, flow and heater control, and materials selection and designing test procedures to resolve, by experimentation, any remaining issues. The conceptual model of the resistojet consists of a shell wrapped by a resistive coil with gases flowing internally through the tube with additional components such as regulators, transducers, and thermocouples. For system performance, the major parameters were calculated from the desired thrust range, the pressure within the resistojet and the cold flow mode of operation; waste gases were analyzed at 100 percent capacity and between 58.95 kPa and 552 kPa. The design team found that any ventilation under all conditions would produce thrust, and therefore, it was decided to limit the design of the ventilation function. The design team proceeded with a simplified model to determine the nozzle throat diameter and chamber diameter.

  13. Space Station Freedom external fluid utilities system design and integration

    NASA Astrophysics Data System (ADS)

    Reinhard, Dawn M.

    1993-02-01

    This paper presents the current Space Station Freedom External Fluid System Design, which is an integrated design of numerous criteria, such as safety, reliability, availability, manufacturability, commonality and compatibility with Extravehicular Activity (EVA). McDonnell Douglas engineers are working to meet a Critical Design Review (CDR) in 1993 and to begin production of fluid system hardware for first launch in 1996, with successive launches continuing through the decade. The fluid system design hardware, such as the 316L Stainless Steel tubing, Inconel, flexible metal hoses, tee fittings, clamping systems and quick disconnect couplings will be presented, with special emphasis on how they were selected in the early phases of the design process. Fabrication and assembly of the Space Station Freedom fluid utility system, using the Numerically Controlled (NC) tube bender and Orbital Welder will be discussed. The Extravehicular Activity (EVA) on-orbit assembly and maintenance techniques of this system will also be briefly explained. Recommendations which have contributed to the success of this design effort include: Consistent communications between groups. a centralized computer-aided drafting/Computer-aided manufacturing (CAD/CAM) system with Electronic Development Fixture (EDF) capability, and technical review boards to control and minimize changes to the design baseline.

  14. Assessment of Space Station design and operation through bioastronautics

    NASA Technical Reports Server (NTRS)

    Klein, K. E.; Wegmann, H. M.; Bluth, B. J.

    1986-01-01

    The main elements which affect human well-being and productivity during a mission on the Space Station are reviewed. These include: the physical environment, the nature of operations the crew is required to perform, man's physiological response to microgravity, and the psychological and social conditions. The individual components of each of these elements are presented, and special design and support needs are identified. Particular attention is given to noise pollution, ionizing radiation, and behavioral factors.

  15. Space crew productivity: A driving factor in space station design

    NASA Technical Reports Server (NTRS)

    Wolbers, H. L.

    1985-01-01

    The criteria of performance, cost, and mission success probability (program confidence) are the principal factors that program or project managers and system engineers use in selecting the optimum design approach for meeting mission objectives. A frame of reference is discussed in which the interrelationships of these pertinent parameters can be made visible, and from which rational or informed decisions can be derived regarding the potential impact of adjustments in crew productivity on total Space Station System effectiveness.

  16. Preliminary space station solar array structural design study

    NASA Technical Reports Server (NTRS)

    Dorsey, J. T.; Bush, H. G.; Mikulas, M. M., Jr.

    1984-01-01

    Structurally efficient ways to support the large solar arrays (3,716 square meters which are currently considered for space station use) are examined. An erectable truss concept is presented for the on orbit construction of winged solar arrays. The means for future growth, maintenance, and repair are integrally designed into this concept. Results from parametric studies, which highlight the physical and structural differences between various configuration options are presented. Consideration is given to both solar blanket and hard panel arrays.

  17. Design and analysis of a chip-scale photonic analog-to-digital converter

    NASA Astrophysics Data System (ADS)

    Sharkawy, Ahmed; Chen, Caihua; Miao, BingLin; Shi, Shouyuan; Prather, Dennis

    2009-05-01

    In this paper, we present novel designs for all optical analog-to-digital converters simulated and realized in photonic crystal platforms. The designs presented were implemented on both photonic bandgap based structures as well as self collimation based structures. Numerical simulation results as well as fabrication results are also included. Characterization results validate the designs presented for a functional all optical two bit analog to digital converters in photonic crystals. The design presented can be further scaled to higher resolution conversion as well as to no optical frequencies if necessary.

  18. Oak Ridge Spallation Neutron Source (ORSNS) target station design integration

    SciTech Connect

    McManamy, T.; Booth, R.; Cleaves, J.; Gabriel, T.

    1996-06-01

    The conceptual design for a 1- to 3-MW short pulse spallation source with a liquid mercury target has been started recently. The design tools and methods being developed to define requirements, integrate the work, and provide early cost guidance will be presented with a summary of the current target station design status. The initial design point was selected with performance and cost estimate projections by a systems code. This code was developed recently using cost estimates from the Brookhaven Pulsed Spallation Neutron Source study and experience from the Advanced Neutron Source Project`s conceptual design. It will be updated and improved as the design develops. Performance was characterized by a simplified figure of merit based on a ratio of neutron production to costs. A work breakdown structure was developed, with simplified systems diagrams used to define interfaces and system responsibilities. A risk assessment method was used to identify potential problems, to identify required research and development (R&D), and to aid contingency development. Preliminary 3-D models of the target station are being used to develop remote maintenance concepts and to estimate costs.

  19. Project EGRESS: Earthbound Guaranteed Reentry from Space Station. the Design of an Assured Crew Recovery Vehicle for the Space Station

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Unlike previously designed space-based working environments, the shuttle orbiter servicing the space station will not remain docked the entire time the station is occupied. While an Apollo capsule was permanently available on Skylab, plans for Space Station Freedom call for a shuttle orbiter to be docked at the space station for no more than two weeks four times each year. Consideration of crew safety inspired the design of an Assured Crew Recovery Vehicle (ACRV). A conceptual design of an ACRV was developed. The system allows the escape of one or more crew members from Space Station Freedom in case of emergency. The design of the vehicle addresses propulsion, orbital operations, reentry, landing and recovery, power and communication, and life support. In light of recent modifications in space station design, Project EGRESS (Earthbound Guaranteed ReEntry from Space Station) pays particular attention to its impact on space station operations, interfaces and docking facilities, and maintenance needs. A water-landing medium-lift vehicle was found to best satisfy project goals of simplicity and cost efficiency without sacrificing safety and reliability requirements. One or more seriously injured crew members could be returned to an earth-based health facility with minimal pilot involvement. Since the craft is capable of returning up to five crew members, two such permanently docked vehicles would allow a full evacuation of the space station. The craft could be constructed entirely with available 1990 technology, and launched aboard a shuttle orbiter.

  20. Space Station Freedom - Approaching the critical design phase

    NASA Technical Reports Server (NTRS)

    Kohrs, Richard H.; Huckins, Earle, III

    1992-01-01

    The status and future developments of the Space Station Freedom are discussed. To date detailed design drawings are being produced to manufacture SSF hardware. A critical design review (CDR) for the man-tended capability configuration is planned to be performed in 1993 under the SSF program. The main objective of the CDR is to enable the program to make a full commitment to proceed to manufacture parts and assemblies. NASA recently signed a contract with the Russian space company, NPO Energia, to evaluate potential applications of various Russian space hardware for on-going NASA programs.

  1. High power density dc/dc converter: Component selection and design

    NASA Technical Reports Server (NTRS)

    Divan, Deepakraj M.

    1989-01-01

    Further work pertaining to design considerations for the new high power, high frequency dc/dc converters is discussed. The goal of the project is the development of high power, high power density dc/dc converters at power levels in the multi-kilowatt to megawatt range for aerospace applications. The prototype converter is rated for 50 kW at a switching frequency of 50 kHz, with an input voltage of 200 Vdc and an output of 2000 Vdc. The overall power density must be in the vicinity of 0.2 to 0.3 kg/kW.

  2. Design of Energy Storage Reactors for Dc-To-Dc Converters. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Chen, D. Y.

    1975-01-01

    Two methodical approaches to the design of energy-storage reactors for a group of widely used dc-to-dc converters are presented. One of these approaches is based on a steady-state time-domain analysis of piecewise-linearized circuit models of the converters, while the other approach is based on an analysis of the same circuit models, but from an energy point of view. The design procedure developed from the first approach includes a search through a stored data file of magnetic core characteristics and results in a list of usable reactor designs which meet a particular converter's requirements. Because of the complexity of this procedure, a digital computer usually is used to implement the design algorithm. The second approach, based on a study of the storage and transfer of energy in the magnetic reactors, leads to a straightforward design procedure which can be implemented with hand calculations. An equation to determine the lower-bound volume of workable cores for given converter design specifications is derived. Using this computer lower-bound volume, a comparative evaluation of various converter configurations is presented.

  3. Verification of Space Station Secondary Power System Stability Using Design of Experiment

    NASA Technical Reports Server (NTRS)

    Karimi, Kamiar J.; Booker, Andrew J.; Mong, Alvin C.; Manners, Bruce

    1998-01-01

    This paper describes analytical methods used in verification of large DC power systems with applications to the International Space Station (ISS). Large DC power systems contain many switching power converters with negative resistor characteristics. The ISS power system presents numerous challenges with respect to system stability such as complex sources and undefined loads. The Space Station program has developed impedance specifications for sources and loads. The overall approach to system stability consists of specific hardware requirements coupled with extensive system analysis and testing. Testing of large complex distributed power systems is not practical due to size and complexity of the system. Computer modeling has been extensively used to develop hardware specifications as well as to identify system configurations for lab testing. The statistical method of Design of Experiments (DoE) is used as an analysis tool for verification of these large systems. DOE reduces the number of computer runs which are necessary to analyze the performance of a complex power system consisting of hundreds of DC/DC converters. DoE also provides valuable information about the effect of changes in system parameters on the performance of the system. DoE provides information about various operating scenarios and identification of the ones with potential for instability. In this paper we will describe how we have used computer modeling to analyze a large DC power system. A brief description of DoE is given. Examples using applications of DoE to analysis and verification of the ISS power system are provided.

  4. A pointing system design concept for Space Station attached payloads

    NASA Technical Reports Server (NTRS)

    Wong, Edward; Rathbun, Dave; Smith, Kenneth

    1989-01-01

    A study has been conducted to recommend a pointing system design and architecture that can accommodate the articulated pointing requirements levied on the Space Station Freedom Attached Payload Pointing System. A conceptual design of a control system is developed using classical rate and position control techniques. A high fidelity simulation testbed has been developed as the principal tool for the pointing performance evaluation. Techniques of model reduction are applied to reduce the model order to a manageable size for incorporation into the testbed. The disturbance rich space station environment has been modeled, and nonlinearities such as bearing friction, motor and sensor noise are also considered. Simulations were performed with representatie payloads at nominal pointing orientations. The results show that the tight instrument pointing requirements and the severe Space Station disturbance environment render a marginal performance for a conventional (direct drive and hardmount) gimbal pointing system, particularly for lightweight payloads. A gimbal system that incorporates a passive base isolator and reactionless actuation appears to provide a significant imporvement in pointing performance over the conventional pointing systems.

  5. A tactical, permanent telemetered volcano monitoring station design

    NASA Astrophysics Data System (ADS)

    Lockhart, A. B.; LaFevers, M.; Couchman, M. R.

    2012-12-01

    The USGS-USAID Volcano Disaster Assistance Program (VDAP) designs, constructs and installs telemetered volcano-monitoring stations for use in developing countries, at a wide range of latitudes and elevations, weather and environmental conditions. The stations typically house seismometers, GPS and webcams, singly or in combination. They are frequently installed quickly during a volcanic crisis, but are expected to function over the long term as permanent stations. The primary design goal is for a simple, highly portable station that can be installed in less than a day, but not require maintenance until the natural end of battery life, usually 2-5 years. The station consists of a pair of aluminum boxes (43x46x71cm, approx.) placed on the ground facing each other, 2-3m apart, forming the lower part of a metal framework made of 2" pipe to mount solar panels and antennae. Vertical sections of 2" pipe, 3-4m long, are clamped to each end of both the boxes, the lower ends buried into cement-filled holes. This makes 4 masts on a rectangular footprint of 1m X 3-4m. Two horizontal crosspieces of 2" pipe 3-4m long are clamped across the masts. Solar panels are laid across the crosspieces, mounted with 2" angle aluminum extending from the high crosspiece to the low one. Relative height of the crosspieces controls the angle of the solar panels. The crosspieces can be lengthened to increase mounting space for additional solar panels. Inside the aluminum boxes, the radios and electronics are housed in plastic boxes. All external cables are protected by flexible aluminum conduit. Important elements of the design include: -Redundant dual solar power supplies of expandable capacity for loads from 1W to 10W or more. -Robust lightning protection afforded by grounded metal footlockers and framework, and a built-in common grounding point. -Strongly resistant to ice loads. -Waterproof, insect-proof plastic boxes for radios and electronics. -Aluminum boxes are easily fabricated, fit within

  6. Using computer graphics to design Space Station Freedom viewing

    NASA Technical Reports Server (NTRS)

    Goldsberry, B. S.; Lippert, B. O.; Mckee, S. D.; Lewis, J. L., Jr.; Mount, F. E.

    1989-01-01

    An important aspect of planning for Space Station Freedom at the United States National Aeronautics and Space Administration (NASA) is the placement of the viewing windows and cameras for optimum crewmember use. Researchers and analysts are evaluating the placement options using a three-dimensional graphics program called PLAID. This program, developed at the NASA Johnson Space Center (JSC), is being used to determine the extent to which the viewing requirements for assembly and operations are being met. A variety of window placement options in specific modules are assessed for accessibility. In addition, window and camera placements are analyzed to insure that viewing areas are not obstructed by the truss assemblies, externally-mounted payloads, or any other station element. Other factors being examined include anthropometric design considerations, workstation interfaces, structural issues, and mechanical elements.

  7. Design and realization of an automatic weather station at island

    NASA Astrophysics Data System (ADS)

    Chen, Yong-hua; Li, Si-ren

    2011-10-01

    In this paper, the design and development of an automatic weather station monitoring is described. The proposed system consists of a set of sensors for measuring meteorological parameters (temperature, wind speed & direction, rain fall, visibility, etc.). To increase the reliability of the system, wind speed & direction are measured redundantly with duplicate sensors. The sensor signals are collected by the data logger CR1000 at several analog and digital inputs. The CR1000 and the sensors form a completely autonomous system which works with the other systems installed in the container. Communication with the master PC is accomplished over the method of Code Division Multiple Access (CDMA) with the Compact Caimore6550P CDMA DTU. The data are finally stored in tables on the CPU as well as on the CF-Card. The weather station was built as an efficient autonomous system which operates with the other systems to provide the required data for a fully automatic measurement system.

  8. Fire Protection Engineering Design Brief Template. Hydrogen Refueling Station.

    SciTech Connect

    LaFleur, Angela Christine; Muna, Alice Baca; Groth, Katrina M.

    2015-08-01

    Building a hydrogen infrastructure system is critical to supporting the development of alternate- fuel vehicles. This report provides a methodology for implementing a performance-based design of an outdoor hydrogen refueling station that does not meet specific prescriptive requirements in NFPA 2, The Hydrogen Technologies Code . Performance-based designs are a code-compliant alternative to meeting prescriptive requirements. Compliance is demonstrated by comparing a prescriptive-based fueling station design with a performance-based design approach using Quantitative Risk Assessment (QRA) methods and hydrogen risk assessment tools. This template utilizes the Sandia-developed QRA tool, Hydrogen Risk Analysis Models (HyRAM), which combines reduced-order deterministic models that characterize hydrogen release and flame behavior with probabilistic risk models to quantify risk values. Each project is unique and this template is not intended to account for site-specific characteristics. Instead, example content and a methodology are provided for a representative hydrogen refueling site which can be built upon for new hydrogen applications.

  9. Natural environment design criteria for the Space Station definition and preliminary design

    NASA Technical Reports Server (NTRS)

    Vaughan, W. W.; Green, C. E.

    1985-01-01

    The natural environment design criteria for the Space Station Program (SSP) definition and preliminary design are presented. Information on the atmospheric, dynamic and thermodynamic environments, meteoroids, radiation, magnetic fields, physical constants, etc. is provided with the intension of enabling all groups involved in the definition and preliminary design studies to proceed with a common and consistent set of natural environment criteria requirements. The space station program elements (SSPE) shall be designed with no operational sensitivity to natural environment conditions during assembly, checkout, stowage, launch, and orbital operations to the maximum degree practical.

  10. A New Design of Seismic Stations Deployed in South Tyrol

    NASA Astrophysics Data System (ADS)

    Melichar, P.; Horn, N.

    2007-05-01

    When designing the seismic network in South Tyrol, the seismic service of Austria and the Civil defense in South Tyrol combined more that 10 years experience in running seismic networks and private communication systems. In recent years the high data return rate of > 99% and network uptime of > 99.% is achieved by the combination of high quality station design and equipment, and the use of the Antelope data acquisition and processing software which comes with suite of network monitoring & alerting tools including Nagios, etc. The new Data Center is located in city of Bolzano and is connected to the other Data Centers in Austria, Switzerland, and Italy for data back up purposes. Each Data Center uses also redundant communication system if the primary system fails. When designing the South Tyrol network, new improvements were made in seismometer installations, grounding, lighting protection and data communications in order to improve quality of data recorded as well as network up-time, and data return. The new 12 stations are equipped with 6 Channels Q330+PB14f connected to STS2 + EpiSensor sensor. One of the key achievements was made in the grounding concept for the whole seismic station - and aluminum boxes were introduced which delivered Faraday cage isolation. Lightning protection devices are used for the equipment inside the aluminum housing where seismometer and data logger are housed. For the seismometer cables a special shielding was introduced. The broadband seismometer and strong-motion sensor are placed on a thick glass plate and therefore isolated from the ground. The precise seismometer orientation was done by a special groove on the glass plate and in case of a strong earthquake; the seismometer is tide up to the base plate. Temperature stability was achieved by styrofoam sheets inside the seismometer aluminum protection box.

  11. Design and experiment of a cross-shaped mode converter for high-power microwave applications

    SciTech Connect

    Peng, Shengren Yuan, Chengwei; Zhong, Huihuang; Fan, Yuwei

    2013-12-15

    A compact mode converter, which is capable of converting a TM{sub 01} mode into a circularly polarized TE{sub 11} mode, was developed and experimentally studied with high-power microwaves. The converter, consisting of two turnstile junctions, is very short along the wave propagation direction, and therefore is suitable for designing compact and axially aligned high-power microwave radiation systems. In this paper, the principle of a converter working at 1.75 GHz is demonstrated, as well as the experimental results. The experimental and simulation results are in good agreement. At the center frequency, the conversion efficiency is more than 95%, the measured axial ratio is about 0.4 dB, and the power-handing capacity is excess of 1.9 GW.

  12. Design feasibility study of a Space Station Freedom truss

    NASA Astrophysics Data System (ADS)

    Armand, Sasan C.; Dohogne, Caroline A.

    1992-04-01

    Here, the focus is on the design and configuration feasibility of the short spacer for the Space Station Program in its launch configuration. The product of this study is being used by Rockwell International (Rocketdyne Division) as they continue their design concept of the current short spacer configuration. It is anticipated that the launch loads will dominate the on-orbit loads and dictate the design configuration of the short spacer. At the present time, the on-orbit loads have not been generated. The structural analysis discussed herein is based on the transient events derived from the Space Transportation System (STS) Interface Control Document (ICD). The transient loading events consist of liftoff loads, landing loads, and emergency landing loads. The quasi-static loading events have been neglected, since the magnitude of the acceleration factors are lower than the transient acceleration factors. The normal mode analyses presented herein are based on the most feasible configurations with acceptable stress ranges.

  13. Target Station Design for the Mu2e Experiment

    SciTech Connect

    Pronskikh, Vitaly; Ambrosio, Giorgio; Campbell, Michael; Coleman, Richard; Ginther, George; Kashikhin, Vadim; Krempetz, Kurt; Lamm, Michael; Lee, Ang; Leveling, Anthony; Mokhov, Nikolai; Nagaslaev, Vladimir; Stefanik, Andrew; Striganov, Sergei; Werkema, Steven; Bartoszek, Larry; Densham, Chris; Loveridge, Peter; Lynch, Kevin; Popp, James

    2014-07-01

    The Mu2e experiment at Fermilab is devoted to search for the conversion of a negative muon into an electron in the field of a nucleus without emission of neutrinos. One of the main parts of the Mu2e experimental setup is its Target Station in which negative pions are generated in interactions of the 8-GeV primary proton beam with a tungsten target. A large-aperture 5-T superconducting production solenoid (PS) enhances pion collection, and an S-shaped transport solenoid (TS) delivers muons and pions to the Mu2e detector. The heat and radiation shield (HRS) protects the PS and the first TS coils. A beam dump absorbs the spent beam. In order for the PS superconducting magnet to operate reliably the sophisticated HRS was designed and optimized for performance and cost. The beam dump was designed to absorb the spent beam and maintaining its temperature and air activation in the hall at the allowable level. Comprehensive MARS15 simulations have been carried out to optimize all the parts while maximizing muon yield. Results of simulations of critical radiation quantities and their implications on the overall Target Station design and integration will be reported.

  14. Spacecraft Station-Keeping Trajectory and Mission Design Tools

    NASA Technical Reports Server (NTRS)

    Chung, Min-Kun J.

    2009-01-01

    Two tools were developed for designing station-keeping trajectories and estimating delta-v requirements for designing missions to a small body such as a comet or asteroid. This innovation uses NPOPT, a non-sparse, general-purpose sequential quadratic programming (SQP) optimizer and the Two-Level Differential Corrector (T-LDC) in LTool (Libration point mission design Tool) to design three kinds of station-keeping scripts: vertical hovering, horizontal hovering, and orbiting. The T-LDC is used to differentially correct several trajectory legs that join hovering points. In a vertical hovering, the maximum and minimum range points must be connected smoothly while maintaining the spacecrafts range from a small body, all within the law of gravity and the solar radiation pressure. The same is true for a horizontal hover. A PatchPoint is an LTool class that denotes a space-time event with some extra information for differential correction, including a set of constraints to be satisfied by T-LDC. Given a set of PatchPoints, each with its own constraint, the T-LDC differentially corrects the entire trajectory by connecting each trajectory leg joined by PatchPoints while satisfying all specified constraints at the same time. Vertical and horizontal hover both are needed to minimize delta-v spent for station keeping. A Python I/F to NPOPT has been written to be used from an LTool script. In vertical hovering, the spacecraft stays along the line joining the Sun and a small body. An instantaneous delta-v toward the anti- Sun direction is applied at the closest approach to the small body for station keeping. For example, the spacecraft hovers between the minimum range (2 km) point and the maximum range (2.5 km) point from the asteroid 1989ML. Horizontal hovering buys more time for a spacecraft to recover if, for any reason, a planned thrust fails, by returning almost to the initial position after some time later via a near elliptical orbit around the small body. The mapping or

  15. A new approach to the minimum weight/loss design of switching power converters

    NASA Technical Reports Server (NTRS)

    Lee, F. C.; Rahman, S.; Wu, C. J.; Kolacki, J.

    1981-01-01

    A new technique using the mathematical nonlinear programming ALAG is proposed to facilitate design optimizations of switching power converters. This computer-aided approach provides a minimum weight (or loss) design down to the details of component level and concurrently satisfies all related power-circuit performance requirements. It also provides such design insights as tradeoffs between power loss and system weight as the switching frequency is increased.

  16. Conceptual Design of the Space Station Fluids Module

    NASA Technical Reports Server (NTRS)

    Rohn, Dennis W.; Morilak, Daniel P.; Rhatigan, Jennifer L.; Peterson, Todd T.

    1994-01-01

    The purpose of this paper is to describe the conceptual design of the Fluids Module for the International Space Station Alpha (ISSA). This module is part of the Space Station Fluids/Combustion Facility (SS FCF) under development at the NASA Lewis Research Center. The Fluids/Combustion Facility is one of several science facilities which are being developed to support microgravity science investigations in the US Laboratory Module of the ISSA. The SS FCF will support a multitude of fluids and combustion science investigations over the lifetime of the ISSA and return state-of-the-art science data in a timely and efficient manner to the scientific communities. This will be accomplished through modularization of hardware, with planned, periodic upgrades; modularization of like scientific investigations that make use of common facility functions; and use of orbital replacement units (ORU's) for incorporation of new technology and new functionality. Portions of the SS FCF are scheduled to become operational on-orbit in 1999. The Fluids Module is presently scheduled for launch to orbit and integration with the Fluids/Combustion Facility in 2001. The objectives of this paper are to describe the history of the Fluids Module concept, the types of fluids science investigations which will be accommodated by the module, the hardware design heritage, the hardware concept, and the hardware breadboarding efforts currently underway.

  17. Conceptual design of the Space Station combustion module

    NASA Technical Reports Server (NTRS)

    Morilak, Daniel P.; Rohn, Dennis W.; Rhatigan, Jennifer L.

    1994-01-01

    The purpose of this paper is to describe the conceptual design of the Combustion Module for the International Space Station Alpha (ISSA). This module is part of the Space Station Fluids/Combustion Facility (SS FCF) under development at the NASA Lewis Research Center. The Fluids/Combustion Facility is one of several science facilities which are being developed to support microgravity science investigations in the US Laboratory Module of the ISSA. The SS FCF will support a multitude of fluids and combustion science investigations over the lifetime of the ISSA and return state-of-the-art science data in a timely and efficient manner to the scientific communities. This will be accomplished through modularization of hardware, with planned, periodic upgrades; modularization of like scientific investigations that make use of common facility functions; and through the use of orbital replacement units (ORU's) for incorporation of new technology and new functionality. The SS FCF is scheduled to become operational on-orbit in 1999. The Combustion Module is presently scheduled for launch to orbit and integration with the Fluids/Combustion Facility in 1999. The objectives of this paper are to describe the history of the Combustion Module concept, the types of combustion science investigations which will be accommodated by the module, the hardware design heritage, the hardware concept, and the hardware breadboarding efforts currently underway.

  18. Design and performance of radioisotope space power systems based on OSC multitube AMTEC converter designs

    SciTech Connect

    Schock, A.; Noravian, H.; Or, C.

    1997-12-31

    This paper extends the analytical procedure described in another paper in these proceedings to analyze a variety of compact and light-weight OSC-designed radioisotope-heated generators. Those generators employed General Purpose Heat Source (GPHS) modules and a converter containing sixteen AMTEC cells of OSC`s revised five-tube design with enhanced cell wall reflectivity described in a companion paper in these proceedings. OSC found that the performance of the generator is primarily a function of the thermal insulation between the outside of the generator`s 16 cells and the inside of its wall. After examining a variety of insulation options, it was found that the generator`s performance is optimized by employing a hybrid insulation system, in which the space between the cells is filled with fibrous Min-K insulation, and the generator walls are lined with tapered (i.e., graded-length) multifoil insulation. The OSC design results in a very compact generator, with eight AMTEC cells on each end of the heat source stack. The choice of the five-tube cells makes it possible to expand the BASE tube diameter without increasing the cell diameter. This is important because the eight cells mate well with the stacked GPHS modules. The OSC generator design includes a compliant heat source support and preload arrangement, to hold the heat source modules together during launch, and to maintain thermal contact conductance at the generator`s interfaces despite creep relaxation of its housing. The BOM and EOM (up to 15 years) performances of the revised generators were analyzed for two and three GPHS modules, both for fresh fuel and for aged fuel left over from a spare RTG (Radioisotope Thermoelectric Generator) fueled in 1982. The resulting power outputs were compared with JPL`s latest EOM power demand goals for the Pluto Express and Europa Orbiter missions, and with the generic goals of DOE`s Advanced Radioisotope Power System (ARPS) study. The OSC AMTEC designs yielded system

  19. H2FIRST Reference Station Design Task: Project Deliverable 2-2

    SciTech Connect

    Pratt, Joseph; Terlip, Danny; Ainscough, Chris; Kurtz, Jennifer; Elgowainy, Amgad

    2015-04-20

    This report presents near-term station cost results and discusses cost trends of different station types. It compares various vehicle rollout scenarios and projects realistic near-term station utilization values using the station infrastructure rollout in California as an example. It describes near-term market demands and matches those to cost-effective station concepts. Finally, the report contains detailed designs for five selected stations, which include piping and instrumentation diagrams, bills of materials, and several site-specific layout studies that incorporate the setbacks required by NFPA 2, the National Fire Protection Association Hydrogen Technologies Code. This work identified those setbacks as a significant factor affecting the ability to site a hydrogen station, particularly liquid stations at existing gasoline stations. For all station types, utilization has a large influence on the financial viability of the station.

  20. A 10kW series resonant converter design, transistor characterization, and base-drive optimization

    NASA Technical Reports Server (NTRS)

    Robson, R.; Hancock, D.

    1981-01-01

    Transistors are characterized for use as switches in resonant circuit applications. A base drive circuit to provide the optimal base drive to these transistors under resonant circuit conditions is developed and then used in the design, fabrication and testing of a breadboard, spaceborne type 10 kW series resonant converter.

  1. Instructional Design Considerations in Converting Non-CBT Materials into CBT Courses.

    ERIC Educational Resources Information Center

    Ng, Raymond

    Instructional designers who are asked to convert existing training materials into computer-based training (CBT) must take special precautions to avoid making the product into a sophisticated page turner. Although conversion may save considerable time on subject research and analysis, courses to be delivered through microcomputers may require…

  2. Space station integrated wall design and penetration damage control

    NASA Technical Reports Server (NTRS)

    Coronado, A. R.; Gibbins, M. N.; Wright, M. A.; Stern, P. H.

    1987-01-01

    The analysis code BUMPER executes a numerical solution to the problem of calculating the probability of no penetration (PNP) of a spacecraft subject to man-made orbital debris or meteoroid impact. The codes were developed on a DEC VAX 11/780 computer that uses the Virtual Memory System (VMS) operating system, which is written in FORTRAN 77 with no VAX extensions. To help illustrate the steps involved, a single sample analysis is performed. The example used is the space station reference configuration. The finite element model (FEM) of this configuration is relatively complex but demonstrates many BUMPER features. The computer tools and guidelines are described for constructing a FEM for the space station under consideration. The methods used to analyze the sensitivity of PNP to variations in design, are described. Ways are suggested for developing contour plots of the sensitivity study data. Additional BUMPER analysis examples are provided, including FEMs, command inputs, and data outputs. The mathematical theory used as the basis for the code is described, and illustrates the data flow within the analysis.

  3. Space Station Human Factors: Designing a Human-Robot Interface

    NASA Technical Reports Server (NTRS)

    Rochlis, Jennifer L.; Clarke, John Paul; Goza, S. Michael

    2001-01-01

    The experiments described in this paper are part of a larger joint MIT/NASA research effort and focus on the development of a methodology for designing and evaluating integrated interfaces for highly dexterous and multifunctional telerobot. Specifically, a telerobotic workstation is being designed for an Extravehicular Activity (EVA) anthropomorphic space station telerobot called Robonaut. Previous researchers have designed telerobotic workstations based upon performance of discrete subsets of tasks (for example, peg-in-hole, tracking, etc.) without regard for transitions that operators go through between tasks performed sequentially in the context of larger integrated tasks. The experiments presented here took an integrated approach to describing teleoperator performance and assessed how subjects operating a full-immersion telerobot perform during fine position and gross position tasks. In addition, a Robonaut simulation was also developed as part of this research effort, and experimentally tested against Robonaut itself to determine its utility. Results show that subject performance of teleoperated tasks using both Robonaut and the simulation are virtually identical, with no significant difference between the two. These results indicate that the simulation can be utilized as both a Robonaut training tool, and as a powerful design platform for telepresence displays and aids.

  4. Improved design of a polarization converter based on semiconductor optical waveguide bends.

    PubMed

    Obayya, S S; Rahman, B M; Grattan, K T; El-Mikati, H A

    2001-10-20

    By using an efficient vector finite-element-based beam-propagation method, we present an improved design of a polarization converter. This design relies on the use of a single-section deeply etched bent semiconductor waveguide with slanted sidewalls. By careful adjustment of the bend radius, the waveguide width, and the sidewall angle we obtained a nearly 100% polarization conversion ratio with no appreciable radiation loss and a bending angle of less than 180 degrees . PMID:18364819

  5. System design and development of a low data rate voice (1200 bps) rate converter

    NASA Astrophysics Data System (ADS)

    Hauser, J. P.

    1992-09-01

    This report presents both a high level and a detailed design for a low data rate voice Rate Converter (RC). On the transmit side, converter reduces 2400 bps voice generated by an Advanced Narrowband Digital Voice Terminal (ANDVT) to a 1200 bps bit stream. On the receive Bide it converts the 1200 bps bit stream back to a 2400 bps stream in ANDVT format. Rate reduction is accomplished with little degradation to the inherent voice quality of the ANDVT. This primary focus is upon the real-time software design which is implemented using VxWorks, a real-time, multi-tasking operating system and development environment. The high level design defines four tasks, each having its own execution thread and its own pipe to facilitate inter-task communication. The Supervisor Task performs initialization and managers input of commands and data to the RC. The Compressor Task reduces a 2400 bps bit stream to 1200 bps while the Decompressor Task converts from 1200 bps back to 2400 bps. The Output Task manages the output of data from the RC. Latter sections of this report describe the software in detail.

  6. Design and Analysis for a Floating Oscillating Surge Wave Energy Converter: Preprint

    SciTech Connect

    Yu, Y. H.; Li, Y.; Hallett, K.; Hotimsky, C.

    2014-03-01

    This paper presents a recent study on the design and analysis of an oscillating surge wave energy converter. A successful wave energy conversion design requires the balance between the design performance and cost. The cost of energy is often used as the metric to judge the design of the wave energy conversion system. It is often determined based on the device power performance, the cost for manufacturing, deployment, operation and maintenance, as well as the effort to ensure the environmental compliance. The objective of this study is to demonstrate the importance of a cost driven design strategy and how it can affect a WEC design. Three oscillating surge wave energy converter (OSWEC) designs were used as the example. The power generation performance of the design was modeled using a time-domain numerical simulation tool, and the mass properties of the design were determined based on a simple structure analysis. The results of those power performance simulations, the structure analysis and a simple economic assessment were then used to determine the cost-efficiency of selected OSWEC designs. Finally, a discussion on the environmental barrier, integrated design strategy and the key areas that need further investigation is also presented.

  7. Design and real time implementation of single phase boost power factor correction converter.

    PubMed

    Bouafassa, Amar; Rahmani, Lazhar; Mekhilef, Saad

    2015-03-01

    This paper presents a real time implementation of the single-phase power factor correction (PFC) AC-DC boost converter. A combination of higher order sliding mode controller based on super twisting algorithm and predictive control techniques are implemented to improve the performance of the boost converter. Due to the chattering effects, the higher order sliding mode control (HOSMC) is designed. Also, the predictive technique is modified taking into account the large computational delays. The robustness of the controller is verified conducting simulation in MATLAB, the results show good performances in both steady and transient states. An experiment is conducted through a test bench based on dSPACE 1104. The experimental results proved that the proposed controller enhanced the performance of the converter under different parameters variations. PMID:25457043

  8. Modeling and controller design of a wind energy conversion system including a matrix converter

    NASA Astrophysics Data System (ADS)

    Barakati, S. Masoud

    and combined to enable steady-state and transient simulations of the overall system. In addition, the constraint constant V/f strategy is included in the final dynamic model. The model is intended to be useful for controller design purposes. The dynamic behavior of the model is investigated by simulating the response of the overall model to step changes in selected input variables. Moreover, a linearized model of the system is developed at a typical operating point, and stability, controllability, and observability of the system are investigated. Two control design methods are adopted for the design of the closed-loop controller: a state-feedback controller and an output feedback controller. The state-feedback controller is designed based on the Linear Quadratic method. An observer block is used to estimate the states in the state-feedback controller. Two other controllers based on transfer-function techniques and output feedback are developed for the wind turbine system. Finally, a maximum power point tracking method, referred to as mechanical speed-sensorless power signal feedback, is developed for the wind turbine system under study to control the matrix converter control variables in order to capture the maximum wind energy without measuring the wind velocity or the turbine shaft speed.

  9. Conceptual design for the space station Freedom modular combustion facility

    NASA Technical Reports Server (NTRS)

    1989-01-01

    A definition study and conceptual design for a combustion science facility that will be located in the Space Station Freedom's baseline U.S. Laboratory module is being performed. This modular, user-friendly facility, called the Modular Combustion Facility, will be available for use by industry, academic, and government research communities in the mid-1990's. The Facility will support research experiments dealing with the study of combustion and its byproducts. Because of the lack of gravity-induced convection, research into the mechanisms of combustion in the absence of gravity will help to provide a better understanding of the fundamentals of the combustion process. The background, current status, and future activities of the effort are covered.

  10. Design and optimization of GaAs photovoltaic converter for laser power beaming

    NASA Astrophysics Data System (ADS)

    Shan, Tiqiang; Qi, Xinglin

    2015-07-01

    GaAs photovoltaic (PV) converters are useful for the conversion of monochromatic light into electrical power in numerous military and industrial applications. The work of this paper is to design a monochromatic GaAs PV converter for coupling to laser beams in the wavelength of 790-840 nm and optimize its structure, layer thicknesses, doping levels of the emitter and base, and antireflection coating. Modeling calculations of the GaAs PV converter optimization are carried out using PC-1D. From the highest efficiency point of view, the best wavelength is 840 nm at which the optimized structure gives an efficiency of 61.8% theoretically. Experiment results under 808 nm laser power beaming show that high optical-to-electrical conversion efficiency of 53.23% at 5 W/cm2 is achieved using the optimized GaAs PV laser converter. Finally, accurate extraction of the key parameters, viz. the ideality factor, reverse saturation current, series resistance and shunt resistance is introduced. Variations of these parameters with illumination intensity are also investigated analytically based on the one diode model, which are necessary for the design of a high performance PV generation system.

  11. Design of an MSAT-X mobile transceiver and related base and gateway stations

    NASA Technical Reports Server (NTRS)

    Fang, Russell J. F.; Bhaskar, Udaya; Hemmati, Farhad; Mackenthun, Kenneth M.; Shenoy, Ajit

    1987-01-01

    This paper summarizes the results of a design study of the mobile transceiver, base station, and gateway station for NASA's proposed Mobile Satellite Experiment (MSAT-X). Major ground segment system design issues such as frequency stability control, modulation method, linear predictive coding vocoder algorithm, and error control technique are addressed. The modular and flexible transceiver design is described in detail, including the core, RF/IF, modem, vocoder, forward error correction codec, amplitude-companded single sideband, and input/output modules, as well as the flexible interface. Designs for a three-carrier base station and a 10-carrier gateway station are also discussed, including the interface with the controllers and with the public-switched telephone networks at the gateway station. Functional specifications are given for the transceiver, the base station, and the gateway station.

  12. Design and performance of the ESA Optical Ground Station

    NASA Astrophysics Data System (ADS)

    Reyes Garcia-Talavera, Marcos; Rodriguez, Jose A.; Viera, Teodora; Moreno-Arce, Heidi; Rasilla, Jose L.; Gago, Fernando; Rodriguez, Luis F.; Gomez, Panchita; Ballesteros Ramirez, Ezequiel

    2002-04-01

    The European Space Agency (ESA) has undertaken the development of Optical Data Relay payloads, aimed at establishing free space optical communication links between satellites. The first of such systems put into orbit is the SILEX project, in which an experimental link between a GEO satellite (ARTEMIS) and a LEO satellite (SPOT IV) will be used to relay earth observation data. In order to perform In Orbit Testing (IOT) of these and future optical communications systems, ESA and the Instituto de Astrofisica de Canarias (IAC) reached an agreement for the building of the Optical Ground Station (OGS) in the IAC Teide Observatory, which consists basically of a 1-meter telescope and the suitable instrumentation for establishing and testing bi-directional optical links with satellites. The presence of the atmosphere in the data path posses particular problems, with an impact on the instrumentation design. The transmission, reception and measurement functions, along with the overall control of the instruments, are performed at OGS by the Focal Plane Control Electronics (FPCE). The design and performance of this instrumentation is presented, emphasizing the Pointing, Acquisition and Tracking, the Tuneable Laser and the Master Control.

  13. Flywheel Energy Storage System Designed for the International Space Station

    NASA Technical Reports Server (NTRS)

    Delventhal, Rex A.

    2002-01-01

    Following successful operation of a developmental flywheel energy storage system in fiscal year 2000, researchers at the NASA Glenn Research Center began developing a flight design of a flywheel system for the International Space Station (ISS). In such an application, a two-flywheel system can replace one of the nickel-hydrogen battery strings in the ISS power system. The development unit, sized at approximately one-eighth the size needed for ISS was run at 60,000 rpm. The design point for the flight unit is a larger composite flywheel, approximately 17 in. long and 13 in. in diameter, running at 53,000 rpm when fully charged. A single flywheel system stores 2.8 kW-hr of useable energy, enough to light a 100-W light bulb for over 24 hr. When housed in an ISS orbital replacement unit, the flywheel would provide energy storage with approximately 3 times the service life of the nickel-hydrogen battery currently in use.

  14. Structural design feasibility study of Space Station long spacer truss

    NASA Technical Reports Server (NTRS)

    Armand, Sasan C.; Funk, Gregory P.; Dohogne, Caroline A.

    1994-01-01

    The structural design and configuration feasibility of the long spacer truss assembly that will be used as part of the Space Station Freedom is the focus of this study. The structural analysis discussed herein is derived from the transient loading events presented in the Space Transportation System Interface Control Document (STS ICD). The transient loading events are liftoff, landing, and emergency landing loads. Quasi-static loading events were neglected in this study since the magnitude of the quasi-static acceleration factors is lower than that of the transient acceleration factors. Structural analysis of the proposed configuration of the long spacer truss with four longerons indicated that negative safety margins are possible. As a result, configuration changes were proposed. The primary configuration change suggested was to increase the number of truss longerons to six. The six-longeron truss appears to be a more promising structure than the four-longeron truss because it offers a positive margin of safety and more volume in its second bay (BAY2). This additional volume can be used for resupply of some of the orbital replacement units (such as a battery box). Note that the design effort on the long spacer truss has not fully begun and that calculations and reports of the negative safety margins are, to date, based on concept only.

  15. Structural design feasibility study of Space Station long spacer truss

    NASA Astrophysics Data System (ADS)

    Armand, Sasan C.; Funk, Gregory P.; Dohogne, Caroline A.

    1994-02-01

    The structural design and configuration feasibility of the long spacer truss assembly that will be used as part of the Space Station Freedom is the focus of this study. The structural analysis discussed herein is derived from the transient loading events presented in the Space Transportation System Interface Control Document (STS ICD). The transient loading events are liftoff, landing, and emergency landing loads. Quasi-static loading events were neglected in this study since the magnitude of the quasi-static acceleration factors is lower than that of the transient acceleration factors. Structural analysis of the proposed configuration of the long spacer truss with four longerons indicated that negative safety margins are possible. As a result, configuration changes were proposed. The primary configuration change suggested was to increase the number of truss longerons to six. The six-longeron truss appears to be a more promising structure than the four-longeron truss because it offers a positive margin of safety and more volume in its second bay (BAY2). This additional volume can be used for resupply of some of the orbital replacement units (such as a battery box). Note that the design effort on the long spacer truss has not fully begun and that calculations and reports of the negative safety margins are, to date, based on concept only.

  16. Resilient design of recharging station networks for electric transportation vehicles

    SciTech Connect

    Kris Villez; Akshya Gupta; Venkat Venkatasubramanian

    2011-08-01

    As societies shift to 'greener' means of transportation using electricity-driven vehicles one critical challenge we face is the creation of a robust and resilient infrastructure of recharging stations. A particular issue here is the optimal location of service stations. In this work, we consider the placement of battery replacing service station in a city network for which the normal traffic flow is known. For such known traffic flow, the service stations are placed such that the expected performance is maximized without changing the traffic flow. This is done for different scenarios in which roads, road junctions and service stations can fail with a given probability. To account for such failure probabilities, the previously developed facility interception model is extended. Results show that service station failures have a minimal impact on the performance following robust placement while road and road junction failures have larger impacts which are not mitigated easily by robust placement.

  17. Engineering design criteria for an image intensifier/image converter camera

    NASA Technical Reports Server (NTRS)

    Sharpsteen, J. T.; Lund, D. L.; Stoap, L. J.; Solheim, C. D.

    1976-01-01

    The design, display, and evaluation of an image intensifier/image converter camera which can be utilized in various requirements of spaceshuttle experiments are described. An image intensifier tube was utilized in combination with two brassboards as power supply and used for evaluation of night photography in the field. Pictures were obtained showing field details which would have been undistinguishable to the naked eye or to an ordinary camera.

  18. Ergonomic implementation and work station design for quilt manufacturing unit

    PubMed Central

    Vinay, Deepa; Kwatra, Seema; Sharma, Suneeta; Kaur, Nirmal

    2012-01-01

    improve the work posture of the worker. The average working heart rate values were found to reduced by performing the activity using improved technology followed by energy expenditure (6.99 kj/min), total cardiac cost of work (1037.95 beats), physiological cost of work (103.79 beats) and rate of perceived rate of exertion to the score of 2.6 Results of postural analysis that is change in motion at cervical region reveal that range of motion in case of extension was found beyond the normal range in existing setup where as it reduced to normal range in improved work station. Conclusion: The finding of the study concludes that to ensure safety and to reduce occupational health hazards while performing the activity, an ergonomically designed work station by introduction of improved technology option will be a right choice which also enhances the productivity. PMID:23580839

  19. 49 CFR 192.163 - Compressor stations: Design and construction.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., each main compressor building of a compressor station must be located on property under the control of... property. There must be enough open space around the main compressor building to allow the free movement of fire-fighting equipment. (b) Building construction. Each building on a compressor station site must...

  20. 49 CFR 192.163 - Compressor stations: Design and construction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., each main compressor building of a compressor station must be located on property under the control of... property. There must be enough open space around the main compressor building to allow the free movement of fire-fighting equipment. (b) Building construction. Each building on a compressor station site must...

  1. 49 CFR 192.163 - Compressor stations: Design and construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., each main compressor building of a compressor station must be located on property under the control of... property. There must be enough open space around the main compressor building to allow the free movement of fire-fighting equipment. (b) Building construction. Each building on a compressor station site must...

  2. 49 CFR 192.163 - Compressor stations: Design and construction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., each main compressor building of a compressor station must be located on property under the control of... property. There must be enough open space around the main compressor building to allow the free movement of fire-fighting equipment. (b) Building construction. Each building on a compressor station site must...

  3. Space Station Cathode Design, Performance, and Operating Specifications

    NASA Technical Reports Server (NTRS)

    Patterson, Michael J.; Verhey, Timothy R.; Soulas, George; Zakany, James

    1998-01-01

    A plasma contactor system was baselined for the International Space Station (ISS) to eliminate/mitigate damaging interactions with the space environment. The system represents a dual-use technology which is a direct outgrowth of the NASA electric propulsion program and, in particular, the technology development efforts on ion thruster systems. The plasma contactor includes a hollow cathode assembly (HCA), a power electronics unit, and a xenon gas feed system. Under a pre-flight development program, these subsystems were taken to the level of maturity appropriate for transfer to U.S. industry for final development. NASA's Lewis Research Center was subsequently requested by ISS to manufacture and deliver the engineering model, qualification model, and flight HCA units. To date, multiple units have been built. One cathode has demonstrated approximately 28,000 hours lifetime, two development unit HCAs have demonstrated over 10,000 hours lifetime, and one development unit HCA has demonstrated more than 32,000 ignitions. All 8 flight HCAs have been manufactured, acceptance tested, and are ready for delivery to the flight contractor. This paper discusses the requirements, mechanical design, performance, operating specifications, and schedule for the plasma contactor flight HCAs.

  4. International Space Station Crew Quarters Ventilation and Acoustic Design Implementation

    NASA Technical Reports Server (NTRS)

    Broyan, James L., Jr.; Cady, Scott M; Welsh, David A.

    2010-01-01

    The International Space Station (ISS) United States Operational Segment has four permanent rack sized ISS Crew Quarters (CQs) providing a private crew member space. The CQs use Node 2 cabin air for ventilation/thermal cooling, as opposed to conditioned ducted air-from the ISS Common Cabin Air Assembly (CCAA) or the ISS fluid cooling loop. Consequently, CQ can only increase the air flow rate to reduce the temperature delta between the cabin and the CQ interior. However, increasing airflow causes increased acoustic noise so efficient airflow distribution is an important design parameter. The CQ utilized a two fan push-pull configuration to ensure fresh air at the crew member's head position and reduce acoustic exposure. The CQ ventilation ducts are conduits to the louder Node 2 cabin aisle way which required significant acoustic mitigation controls. The CQ interior needs to be below noise criteria curve 40 (NC-40). The design implementation of the CQ ventilation system and acoustic mitigation are very inter-related and require consideration of crew comfort balanced with use of interior habitable volume, accommodation of fan failures, and possible crew uses that impact ventilation and acoustic performance. Each CQ required 13% of its total volume and approximately 6% of its total mass to reduce acoustic noise. This paper illustrates the types of model analysis, assumptions, vehicle interactions, and trade-offs required for CQ ventilation and acoustics. Additionally, on-orbit ventilation system performance and initial crew feedback is presented. This approach is applicable to any private enclosed space that the crew will occupy.

  5. Design and Operation of Infrasound Stations for Hazardous Weather Detection

    NASA Astrophysics Data System (ADS)

    Pepyne, D.

    2012-04-01

    Each year tornadoes cause property damage and death, some of which could be avoided with increased warning lead time. The year 2011 was particularly severe, with more than 1600 tornadoes causing in excess of 500 deaths in the U.S. It is known that tornadoes and their precursors generate infrasound in the 0.5Hz to 10Hz frequency band, with precursors occurring some 30-60 minutes prior to tornado touch down, which is some 15-45 minutes earlier than the average tornado warning lead time in the U.S. Given the potential of infrasound to improve tornado early warning and emergency response, the Center for Collaborative Adaptive Sensing of the Atmosphere (CASA), in conjunction with its research on small, boundary-layer observing X-band weather radars, has begun a research project whose goal is to combine the passive detection of tornado infrasound with active tracking of the parent storms that carry the tornadoes with its weather radars. In the spring of 2011 CASA conducted an infrasound field-test in Oklahoma, in the heart of the so-called "tornado-alley" where statistically the majority of springtime tornadoes in the U.S. occur. This being CASA's first infrasound experiment, the goal of the field-test was to gain an understanding of the issues involved in the design and operation of infrasound stations for severe weather monitoring and early warning. In this application, it is not so much the ability of infrasound to travel long distances that is of importance, but rather the fact that there can be precursor signals that unlike radar do not require line-of-sight to detect. In fact, for early warning, detection distance would generally need to be less than 100 km, since a propagation delay of much more than 5 minutes would be too late. Challenges encountered included persistent infrasound "clutter" from a nearby large windfarm, accurate bearing detection over a wide bandwidth with a fixed four sensor aperture, and the need to operate in the the high winds that surround

  6. Development of a fuzzy logic controller for dc/dc converters: Design, computer simulation, and experimental evaluation

    SciTech Connect

    So, W.C.; Tse, C.K.; Lee, Y.S.

    1996-01-01

    The design of a fuzzy logic controller for dc/dc converters is described in this paper. A brief review of fuzzy logic and its application to control is first given. Then, the derivation of a fuzzy control algorithm for regulating dc/dc converters is described in detail. The proposed fuzzy control is evaluated by computer simulations as well as experimental measurements of the closed-loop performance of simple dc/dc converters in respect of load regulation and line regulation.

  7. Design of a high efficiency 30 kW boost composite converter

    SciTech Connect

    Kim, Hyeokjin; Chen, Hua; Maksimovic, Dragan; Erickson, Robert W.

    2015-09-20

    An experimental 30 kW boost composite converter is described in this paper. The composite converter architecture, which consists of a buck module, a boost module, and a dual active bridge module that operates as a DC transformer (DCX), leads to substantial reductions in losses at partial power points, and to significant improvements in weighted efficiency in applications that require wide variations in power and conversion ratio. A comprehensive loss model is developed, accounting for semiconductor conduction and switching losses, capacitor losses, as well as dc and ac losses in magnetic components. Based on the developed loss model, the module and system designs are optimized to maximize efficiency at a 50% power point. Experimental results for the 30 kW prototype demonstrate 98.5%peak efficiency, very high efficiency over wide ranges of power and voltage conversion ratios, as well as excellent agreements between model predictions and measured efficiency curves.

  8. Analysis and Design of Crew Sleep Station for ISS

    NASA Technical Reports Server (NTRS)

    Keener, John F.; Paul, Thomas; Eckhardt, Bradley; Smith, Fredrick

    2002-01-01

    This paper details the analysis and design of the Temporary Sleep Station (TeSS) environmental control system for International Space Station (ISS). The TeSS will provide crewmembers with a private and personal space, to accommodate sleeping, donning and doffing of clothing, personal communication and performance of recreational activities. The need for privacy to accommodate these activities requires adequate ventilation inside the TeSS. This study considers whether temperature, carbon dioxide, and humidity within the TeSS remain within crew comfort and safety levels for various expected operating scenarios. Evaluation of these scenarios required the use and integration of various simulation codes. An approach was adapted for this study, whereby results from a particular code were integrated with other codes when necessary. Computational Fluid Dynamics (CFD) methods were used to evaluate the flow field inside the TeSS, from which local gradients for temperature, velocity, and species concentration such as CO (sub 2) could be determined. A model of the TeSS, containing a human, as well as equipment such as a laptop computer, was developed in FLUENT, a finite-volume code. Other factors, such as detailed analysis of the heat transfer through the structure, radiation, and air circulation from the TeSS to the US Laboratory Aisle, where the TeSS is housed, were considered in the model. A complementary model was developed in G189A, a code which has been used by NASA/JSC for environmental control systems analyses since the Apollo program. Boundary conditions were exchanged between the FLUENT and G189A TeSS models. G189A provides human respiration rates to the FLUENT model, while the FLUENT model provides local convective heat transfer coefficients to G189A model. An additional benefit from using an approach with both a systems simulation and CFD model, is the capability to verify the results of each model by comparison to the results of the other model. The G189A and

  9. 49 CFR 192.163 - Compressor stations: Design and construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... property. There must be enough open space around the main compressor building to allow the free movement of... wall must be mounted to swing outward. (d) Fenced areas. Each fence around a compressor station...

  10. Using computer graphics to design Space Station Freedom viewing

    NASA Technical Reports Server (NTRS)

    Goldsberry, Betty S.; Lippert, Buddy O.; Mckee, Sandra D.; Lewis, James L., Jr.; Mount, Francis E.

    1993-01-01

    Viewing requirements were identified early in the Space Station Freedom program for both direct viewing via windows and indirect viewing via cameras and closed-circuit television (CCTV). These requirements reside in NASA Program Definition and Requirements Document (PDRD), Section 3: Space Station Systems Requirements. Currently, analyses are addressing the feasibility of direct and indirect viewing. The goal of these analyses is to determine the optimum locations for the windows, cameras, and CCTV's in order to meet established requirements, to adequately support space station assembly, and to operate on-board equipment. PLAID, a three-dimensional computer graphics program developed at NASA JSC, was selected for use as the major tool in these analyses. PLAID provides the capability to simulate the assembly of the station as well as to examine operations as the station evolves. This program has been used successfully as a tool to analyze general viewing conditions for many Space Shuttle elements and can be used for virtually all Space Station components. Additionally, PLAID provides the ability to integrate an anthropometric scale-modeled human (representing a crew member) with interior and exterior architecture.

  11. Man/machine interface for a nuclear cask remote handling control station: system design requirements

    SciTech Connect

    Clarke, M.M.; Kreifeldt, J.G.; Draper, J.V.

    1984-07-09

    Design requirements are presented for a control station of a proposed semi-automated facility for remote handling of nuclear waste casks. Functional and operational man/machine interface: controls, displays, software format, station architecture, and work environment. In addition, some input is given to the design of remote sensing systems in the cask handling areas. 18 references, 9 figures, 12 tables.

  12. The hydraulic design of pump turbine for Xianyou pumped storage power station

    NASA Astrophysics Data System (ADS)

    Zheng, J. S.; Liu, W. C.; Fu, Z. Y.; Shi, Q. H.

    2012-11-01

    This paper presents the hydraulic design of pump turbines for Xianyou pumped storage power station. The method of improving the hydraulic performance of pump turbine with CFD analysis is given. The results of model test indicate that the final hydraulic design of pump turbine for Xianyou pumped storage power station is of high efficiencies, good

  13. Design and simulation of a fast-charging station for plug-in hybrid electric vehicle (PHEV) batteries

    NASA Astrophysics Data System (ADS)

    de Leon, Nathalie Pulmones

    2011-12-01

    With the increasing interest in green technologies in transportation, plug-in hybrid electric vehicles (PHEV) have proven to be the best short-term solution to minimize greenhouse gas emissions. Despite such interest, conventional vehicle drivers are still reluctant in using such a new technology, mainly because of the long duration (4-8 hours) required to charge PHEV batteries with the currently existing Level I and II chargers. For this reason, Level III fast-charging stations capable of reducing the charging duration to 10-15 minutes are being considered. The present thesis focuses on the design of a fast-charging station that uses, in addition to the electrical grid, two stationary energy storage devices: a flywheel energy storage and a supercapacitor. The power electronic converters used for the interface of the energy sources with the charging station are designed. The design also focuses on the energy management that will minimize the PHEV battery charging duration as well as the duration required to recharge the energy storage devices. For this reason, an algorithm that minimizes durations along with its mathematical formulation is proposed, and its application in fast charging environment will be illustrated by means of two scenarios.

  14. Crew Restraint Design for the International Space Station

    NASA Technical Reports Server (NTRS)

    Norris, Lena; Holden, Kritina; Whitmore, Mihriban

    2006-01-01

    With permanent human presence onboard the International Space Station (ISS), crews will be living and working in microgravity, dealing with the challenges of a weightless environment. In addition, the confined nature of the spacecraft environment results in ergonomic challenges such as limited visibility and access to the activity areas, as well as prolonged periods of unnatural postures. Without optimum restraints, crewmembers may be handicapped for performing some of the on-orbit tasks. Currently, many of the tasks on ISS are performed with the crew restrained merely by hooking their arms or toes around handrails to steady themselves. This is adequate for some tasks, but not all. There have been some reports of discomfort/calluses on the top of the toes. In addition, this type of restraint is simply insufficient for tasks that require a large degree of stability. Glovebox design is a good example of a confined workstation concept requiring stability for successful use. They are widely used in industry, university, and government laboratories, as well as in the space environment, and are known to cause postural limitations and visual restrictions. Although there are numerous guidelines pertaining to ventilation, seals, and glove attachment, most of the data have been gathered in a 1-g environment, or are from studies that were conducted prior to the early 1980 s. Little is known about how best to restrain a crewmember using a glovebox in microgravity. Another ISS task that requires special consideration with respect to restraints is robotic teleoperation. The Robot Systems Technology Branch at the NASA Johnson Space Center is developing a humanoid robot astronaut, or Robonaut. It is being designed to perform extravehicular activities (EVAs) in the hazardous environment of space. An astronaut located inside the ISS will remotely operate Robonaut through a telepresence control system. Essentially, the robot mimics every move the operator makes. This requires the

  15. Design of photon converter and photoneutron target for High power electron accelerator based BNCT.

    PubMed

    Rahmani, Faezeh; Seifi, Samaneh; Anbaran, Hossein Tavakoli; Ghasemi, Farshad

    2015-12-01

    An electron accelerator, ILU-14, with current of 10 mA and 100 kW in power has been considered as one of the options for neutron source in Boron Neutron Capture Therapy (BNCT). The final design of neutron target has been obtained using MCNPX to optimize the neutron production. Tungsten in strip shape and D2O in cylindrical form have been proposed as the photon converter and the photoneutron target, respectively. In addition calculation of heat deposition in the photon target design has been considered to ensure mechanical stability of target. The results show that about 8.37×10(12) photoneutron/s with average energy of 615 keV can be produced by this neutron source design. In addition, using an appropriate beam shaping assembly an epithermal neutron flux of the order of 1.24×10(8) cm(-2) s(-1) can be obtained for BNCT applications. PMID:26278347

  16. Target station design for a 1 MW pulsed spallation neutron source

    SciTech Connect

    Russell, G.J.; Baker, G.D.; Brewton, R.J.

    1993-12-31

    Target stations are vital components of the 1 MW, next generation spallation neutron source proposed for LANSCE. By and large, target stations design determines the overall performance of the facility. Many traditional concepts will probably have to be rethought, and many new concepts will have to be put forward to meet the 1 MW challenge. This article gives a brief overview of the proposed neutron spallation source from the target station viewpoint, as well as the general philosophy adopted for the design of the LANSCE-II target stations. Some of the saliant concepts and features envisioned for LANSCE-II are briefly described.

  17. Incorporation of privacy elements in space station design

    NASA Technical Reports Server (NTRS)

    Harrison, Albert A.; Caldwell, Barrett; Struthers, Nancy J.

    1988-01-01

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

  18. Artificial gravity studies and design considerations for Space Station centrifuges

    NASA Technical Reports Server (NTRS)

    Halstead, T. W.; Brown, A. H.; Fuller, C. A.; Oyama, J.

    1984-01-01

    The requirements to and capabilities of a Space Station biological facility centrifuge are discussed on the basis of an assessment of the objectives and subjects of future microgravity biological experiments. It is argued that the facility should be capable of both acute and extended chronic exposure of test subjects and biological materials to altered-g loading. In addition, the experimental approaches and equipment for microgravity studies on a Space Station are outlined. Finally, the engineering requirements of such a centrifuge are examined, with consideration of radial gravity gradients, size, and physical access to animals.

  19. Electrical power system design for the US space station

    NASA Technical Reports Server (NTRS)

    Nored, Donald L.; Bernatowicz, Daniel T.

    1986-01-01

    The multipurpose, manned, permanent space station will be our next step toward utilization of space. A multikilowatt electrical power system will be critical to its success. The power systems for the space station manned core and platforms that have been selected in definition studies are described. The system selected for the platforms uses silicon arrays and Ni-H2 batteries. The power system for the manned core is a hybrid employing arrays and batteries identical to those on the platform along with solar dynamic modules using either Brayton or organic Rankine engines. The power system requirements, candidate technologies, and configurations that were considered, and the basis for selection, are discussed.

  20. International interface design for Space Station Freedom - Challenges and solutions

    NASA Technical Reports Server (NTRS)

    Mayo, Richard E.; Bolton, Gordon R.; Laurini, Daniele

    1988-01-01

    The definition of interfaces for the International Space Station is discussed, with a focus on negotiations between NASA and ESA. The program organization and division of responsibilities for the Space Station are outlined; the basic features of physical and functional interfaces are described; and particular attention is given to the interface management and documentation procedures, architectural control elements, interface implementation and verification, and examples of Columbus interface solutions (including mechanical, ECLSS, thermal-control, electrical, data-management, standardized user, and software interfaces). Diagrams, drawings, graphs, and tables listing interface types are provided.

  1. Design and development of electric vehicle charging station equipped with RFID

    NASA Astrophysics Data System (ADS)

    Panatarani, C.; Murtaddo, D.; Maulana, D. W.; Irawan, S.; Joni, I. M.

    2016-02-01

    This paper reports the development of electric charging station from distributed renewable for electric vehicle (EV). This designed refer to the input voltage standard of IEC 61851, plugs features of IEC 62196 and standard communication of ISO 15118. The developed electric charging station used microcontroller ATMEGA8535 and RFID as controller and identifier of the EV users, respectively. The charging station successfully developed as desired features for electric vehicle from renewable energy resources grid with solar panel, wind power and batteries storage.

  2. The Space Station program definition and preliminary systems design - Recent developments

    NASA Technical Reports Server (NTRS)

    Freitag, R. F.

    1985-01-01

    It is pointed out that space stations represent a major vehicle for accomplishing many things mankind envisions for space activities. Thus, space stations have become necessary stepping-off points for deep-space expeditions, and it is expected that they will lead eventually to the permanent occupancy of another planet. The present paper provides a report regarding planning activities in the U.S. and in other countries which have made significant progress in making a permanent Space Station a reality. The Space Station will consist of a manned base and associated platforms, as well as collateral support equipment. The purpose of the program definition and preliminary design activities (Phase B) is to arrive at the baseline configuration before initiating actual hardware development. Details of the program plan are discussed along with user considerations in design, the commercialization of space, design issues, operations, and Space Station evolution.

  3. The design and development of a mobile transporter system for the Space Station Remote Manipulator System

    NASA Technical Reports Server (NTRS)

    Carroll, Thomas W.

    1987-01-01

    The analyses, selection process, and conceptual design of potential candidate Mobile Transporter (MT) systems to move the Space Station Remote Manipulator System (SSRMS) about the exposed faces of the Space Station truss structure are described. The actual requirements for a manipulator system on the space station are discussed, including potential tasks to be performed. The SSRMS operating environment and control methods are analyzed with potential design solutions highlighted. Three general categories of transporter systems are identified and analyzed. Several design solution have emerged that will satisfy these requirements. Their relative merits are discussed, and unique variations in each system are rated for functionality.

  4. Early engineering designs of space stations in the United States: A memoir

    NASA Astrophysics Data System (ADS)

    Kramer, Saunders B.

    1993-05-01

    Inspired by the Soviet Union's orbiting of Sputnik 1, in April 1958 the author began to study the possibilities of manned flight into space by the end of the coming decade. Efforts were pointed towards the design of several manned space stations to be placed in low Earth orbit. This paper describes concepts that evolved from an initial space station design prepared in 1958 to more mature approaches appearing in 1960 and in 1962. Variation in design concepts, efforts to resolve problems affecting on-board crews, and the need to assemble stations from many separate modules are among the subjects considered.

  5. User's manual: Computer-aided design programs for inductor-energy-storage dc-to-dc electronic power converters

    NASA Technical Reports Server (NTRS)

    Huffman, S.

    1977-01-01

    Detailed instructions on the use of two computer-aided-design programs for designing the energy storage inductor for single winding and two winding dc to dc converters are provided. Step by step procedures are given to illustrate the formatting of user input data. The procedures are illustrated by eight sample design problems which include the user input and the computer program output.

  6. Designing acoustic-electric strain-gauge converters for sensitive diaphragm elements

    NASA Astrophysics Data System (ADS)

    Chernyak, M. G.; Kovalenko, T. V.

    Analytic expressions and nomograms are obtained to estimate the sensitivity of differential acoustic-electric measuring pressure converter with an error no more than 5% and to choose such an arrangement of strain-gauge converters on its sensitive diaphragm element that would ensure an additive temperature error of the measuring pressure converter less than 10-4 K-1

  7. Design of piezoelectric transformer for DC/DC converter with stochastic optimization method

    NASA Astrophysics Data System (ADS)

    Vasic, Dejan; Vido, Lionel

    2016-04-01

    Piezoelectric transformers were adopted in recent year due to their many inherent advantages such as safety, no EMI problem, low housing profile, and high power density, etc. The characteristics of the piezoelectric transformers are well known when the load impedance is a pure resistor. However, when piezoelectric transformers are used in AC/DC or DC/DC converters, there are non-linear electronic circuits connected before and after the transformer. Consequently, the output load is variable and due to the output capacitance of the transformer the optimal working point change. This paper starts from modeling a piezoelectric transformer connected to a full wave rectifier in order to discuss the design constraints and configuration of the transformer. The optimization method adopted here use the MOPSO algorithm (Multiple Objective Particle Swarm Optimization). We start with the formulation of the objective function and constraints; then the results give different sizes of the transformer and the characteristics. In other word, this method is looking for a best size of the transformer for optimal efficiency condition that is suitable for variable load. Furthermore, the size and the efficiency are found to be a trade-off. This paper proposes the completed design procedure to find the minimum size of PT in need. The completed design procedure is discussed by a given specification. The PT derived from the proposed design procedure can guarantee both good efficiency and enough range for load variation.

  8. Obese humans as economically designed feed converters: symmorphosis and low oxidative capacity skeletal muscle.

    PubMed

    Hudson, Nicholas J; Lehnert, Sigrid A; Harper, Gregory S

    2008-01-01

    Human obesity is considered a consequence of a thrifty or economic metabolism. In this hypothesis, we apply an established economic design theory, called symmorphosis, to help explain the known association between obesity and low oxidative capacity skeletal muscle. Symmorphosis reflects an engineering principle, and predicts that physiological systems are most economically designed when unnecessary spare capacity is eliminated. This is because the structural/functional adaptations accounting for spare capacity themselves bear energetic costs of construction, maintenance and load. As oxidation of feed energy occurs in mitochondria, and because skeletal muscle accounts for 30% of resting metabolism, we focus on skeletal muscle mitochondria. In the same way that the most economically designed elevator is supported by a cable that is strong enough, but not too strong, symmorphosis predicts that the most economically designed feed converters should have enough, but not too much mitochondrial oxidative (fuel burning) capacity. While ATP demand is clearly more efficiently met by oxidative (38 molecules of ATP) rather than glycolytic (2 molecules of ATP) metabolism, symmorphosis predicts that having excess oxidative capacity actually reduces feed efficiency. This inefficiency is manifest by having to maintain, ultimately using feed energy, the expensive inner mitochondrial proton gradient in the superfluous mitochondria. On this basis, we predict that established molecular controllers of mitochondrial biogenesis and oxidative capacity such as eNOS, SIN3 co-repressor, TFAM and PPARgamma may yield useful DNA markers and therapeutic targets for issues relating to frugal energetics, namely predisposition to obesity and starvation resilience. PMID:17664046

  9. Designing a new post-hole seismological station on Antarctica inlandsis (Concordia station)

    NASA Astrophysics Data System (ADS)

    Bès de Berc, M.; Maggi, A.; Leveque, J. J.; Thore, J. Y.

    2015-12-01

    Concordia (75°S 123°E) is a scientific base operated by French and Italian polar institutes IPEV (Institut Paul-Emile Victor) and PNRA (Programma Nazionale di Ricerche in Antartide, and is located on the inlandsis of the East Antarctica plateau. It hosts a seismological station CCD which has provided observatory quality data since the year 2000, has been integrated into the Geoscope network since 2008 and whose data are now available in real-time from IRIS. The current seismic vault is located 800m from Concordia base, as far away as is deemed logistically possible by IPEV, at a depth of 12m. The vault is thermally very stable, but given the close distance to the base, suffers from increased diurnal noise (up to 40 dB) at frequencies above 1Hz, especially in the summer season. Anthropic noise is trapped in the firn (snow) layer, which forms an 100-110m thick waveguide, and is picked up very easily in the seismic vault. The vault is made from steel containers buried vertically in the snow. The hydrostatic pressure of the snow is deforming them: we see container cracking events on the seismograms, and also visual evidence of container deformation inside the vault. In the near future, this deformation will create a security problem.We have decided to progressively abandon our current vault, and construct a new post-hole seismological installation nearby. We plan to drill to 130m depth, which would place us below the firn layer waveguide and also below the ice pinch-out depth. To be able to run the station for several years and change or service the instrumentation if required, we need to keep the hole open, to avoid any hydrostatic movement, and to maintain good coupling between the sensor and the surrounding hard ice. To achieve these goals, we shall install a casing in the fin layer and then drill a few meters more without casing in hard ice. After installing the instrument, we shall then fill the whole hole with a drilling fluid whose density is similar to that

  10. The Long Wavelength Array -- LWA Prototype Station Design

    NASA Astrophysics Data System (ADS)

    Gausiran, T. L., II; Kerkhoff, A.; York, J.; Slack, C.

    2005-12-01

    This paper describes the current vision of the Long Wavelength Demonstrator Array (LWDA) as well as some thoughts on the LWA as of September 2004. This concept is certain to evolve as we work towards the actual construction of the LWDA and the LWA. As envisioned, the LWA will provide unprecedented sensitivity and angular resolution in low frequency bands to radio astronomers allowing observations that were previously unavailable. We will investigate the LWDA by starting at the station level and working down to the component level of detail. This treatment should provide persons new to the LWA the ``big picture'' first and then move towards the details.

  11. Design and characterization of silicon-on-insulator passive polarization converter with finite-element analysis

    NASA Astrophysics Data System (ADS)

    Deng, Henghua

    In this dissertation; the silicon-on-insulator (SOI) technology is introduced to the design and fabrication of passive polarization rotators (PR). Efficient and accurate full-vectorial finite-element eigenmode solvers as well as propagation schemes for characterizing novel SOI PRs are developed because commercial software packages based on finite-difference techniques are inefficient in dealing with arbitrary waveguide geometries. A novel configuration with asymmetric external waveguiding layers is proposed, which is advantageous for fabrication procedure, manufacturing tolerance, single-mode region, and conversion efficiency. By etching along the crystallographic plane, the angled-facet can be perfectly fabricated. Completely removing external waveguiding layer beside the sloped sidewall not only simplifies production procedures but also enhances fabrication tolerances. To accurately and efficiently characterize asymmetric slanted-angle SOI polarization converters, adaptive mesh generation procedures are incorporated into our finite-clement method (FEM) analysis. In addition, anisotropic perfectly-matched-layer (PML) boundary condition (BC) is employed in the beam propagation method (BPM) in order to effectively suppress reflections from the edges of the computation window. For the BPM algorithm, the power conservation is strictly monitored, the non-unitarity is thoroughly analyzed, and the inherent numerical dissipation is reduced by adopting the quasi-Crank-Nicholson scheme and adaptive complex reference index. Advantages of SOI polarization rotators over III-V counterparts are studied through comprehensive research on power exchange, single-mode condition, fabrication tolerance, wavelength stability, bending characteristics, loss and coupling properties. The performance of SOI PRs is stable for wavelengths in the ITU-T C-band and L-band, making such devices quite suitable for DWDM applications. Due to the flexible cross-section of SOI polarization converters

  12. Status of the Space Station environmental control and life support system design concept

    NASA Technical Reports Server (NTRS)

    Ray, C. D.; Humphries, W. R.

    1986-01-01

    The current status of the Space Station (SS) environmental control and life support system (ECLSS) design is outlined. The concept has been defined at the subsystem level. Data supporting these definitions are provided which identify general configuratioons for all modules. Requirements, guidelines and assumptions used in generating these configurations are detailed. The basic 2 US module 'core' Space Station is addressed along with system synergism issues and early man-tended and future growth considerations. Along with these basic studies, also addressed here are options related to variation in the 'core' module makeup and more austere Station concepts such as commonality, automation and design to cost.

  13. Considerations in the design of life sciences research facilities for the Space Station

    NASA Technical Reports Server (NTRS)

    Heinrich, M.; Rudiger, C. E.

    1985-01-01

    The facilities required for life science research on a permanent Space Station are examined. Specifications important to the designing of facilities and planning of activities on the Space Shuttle are: (1) the species to be tested, (2) the number and procedure for testing, (3) the number of specimens at each sampling time, (4) the analyses required, (5) the methods of preserving samples, instruments, and supplies, and (6) the amount of crew time required. Experiments which are relevant to understanding the effects of microgravity on living systems are to be performed on the Space Station. The design and instruments of a Space Station laboratory and specimen centrifuge are described.

  14. Space Station Freedom power supply commonality via modular design

    NASA Technical Reports Server (NTRS)

    Krauthamer, S.; Gangal, M. D.; Das, R.

    1990-01-01

    At mature operations, Space Station Freedom will need more than 2000 power supplies to feed housekeeping and user loads. Advanced technology power supplies from 20 to 250 W have been hybridized for terrestrial, aerospace, and industry applications in compact, efficient, reliable, lightweight packages compatible with electromagnetic interference requirements. The use of these hybridized packages as modules, either singly or in parallel, to satisfy the wide range of user power supply needs for all elements of the station is proposed. Proposed characteristics for the power supplies include common mechanical packaging, digital control, self-protection, high efficiency at full and partial loads, synchronization capability to reduce electromagnetic interference, redundancy, and soft-start capability. The inherent reliability is improved compared with conventional discrete component power supplies because the hybrid circuits use high-reliability components such as ceramic capacitors. Reliability is further improved over conventional supplies because the hybrid packages, which may be treated as a single part, reduce the parts count in the power supply.

  15. Design of A 5-Bit Fully Parallel Analog to Digital Converter Using Common Gate Differrential Mos Pair-Based Comparator

    NASA Astrophysics Data System (ADS)

    Aytar, Oktay

    2015-09-01

    This paper presents a novel comparator structure based on the common gate differential MOS pair. The proposed comparator has been applied to fully parallel analog to digital converter (A/D converter). Furthermore, this article presents 5 bit fully parallel A/D Converter design using the cadence IC5141 design platform and NCSU(North Carolina State University) design kit with 0.18 μm CMOS technology library. The proposed fully parallel A/D converter consist of resistor array block, comparator block, 1-n decoder block and programmable logic array. The 1-n decoder block includes latch block and thermometer code circuit that is implemented using transmission gate based multiplexer circuit. Thus, sampling frequency and analog bandwidth are increased. The INL and DNL of the proposed fully parallel A/D converter are (0/ + 0.63) LSB and (-0.26/ + 0.31) LSB at a sampling frequency of 5 GS/s with an input signal of 50 MHz, respectively. The proposed fully parallel A/D Converter consumes 340 mW from 1.8 V supply.

  16. Manipulator arm design for the Extravehicular Teleoperator Assist Robot (ETAR): Applications on the space station

    NASA Technical Reports Server (NTRS)

    Clarke, Margaret M.; Divona, Charles J.; Thompson, William M.

    1987-01-01

    The preliminary conceptual design of a new teleoperator robot manipulator system for space station maintenance missions has been completed. The system consists of a unique pair of arms that is part of a master-slave, force-reflecting servomanipulator. This design allows greater dexterity and greater volume coverage than that available in current designs and concepts. The teleoperator manipulator is specifically designed for space applications and is a valuable extension of the current state-of-the-art earthbound manipulators marketed today. The manipulator and its potential application on the space station are described.

  17. Preliminary Design of Monitoring and Control Subsystem for GNSS Ground Station

    NASA Astrophysics Data System (ADS)

    Jeong, Seongkyun; Lee, Jae-Eun; Park, Hanearl; Lee, Sanguk; Kim, Jaehoon

    2008-06-01

    GNSS (Global Navigation Satellite System) Ground Station monitors navigation satellite signal, analyzes navigation result, and uploads correction information to satellite. GNSS Ground Station is considered as a main object for constructing GNSS infra-structure and applied in various fields. ETRI (Electronics and Telecommunications Research Institute) is developing Monitoring and Control subsystem, which is subsystem of GNSS Ground Station. Monitoring and Control subsystem acquires GPS and Galileo satellite signal and provides signal monitoring data to GNSS control center. In this paper, the configurations of GNSS Ground Station and Monitoring and Control subsystem are introduced and the preliminary design of Monitoring and Control subsystem is performed. Monitoring and Control subsystem consists of data acquisition module, data formatting and archiving module, data error correction module, navigation solution determination module, independent quality monitoring module, and system operation and maintenance module. The design process uses UML (Unified Modeling Language) method which is a standard for developing software and consists of use-case modeling, domain design, software structure design, and user interface structure design. The preliminary design of Monitoring and Control subsystem enhances operation capability of GNSS Ground Station and is used as basic material for detail design of Monitoring and Control subsystem.

  18. The Electromagnetic Compatibility (EMC) Design Challenge for Scientific Spacecraft Powered by a Stirling Power Converter

    NASA Technical Reports Server (NTRS)

    Sargent, Noel B.

    2001-01-01

    A 55 We free-piston Stirling Technology Demonstration Convertor (TDC) has been tested as part of an evaluation to determine its feasibility as a means for significantly reducing the amount of radioactive material required compared to Radioisotope Thermoelectric Generators (RTGs) to support long-term space science missions. Measurements were made to quantify the low frequency magnetic and electric fields radiated from the Stirling's 80 Hertz (Hz) linear alternator and control electronics in order to determine the magnitude of reduction that will be required to protect sensitive field sensors aboard some science missions. One identified "Solar Probe" mission requires a 100 dB reduction in the low frequency magnetic field over typical military standard design limits, to protect its plasma wave sensor. This paper discusses the electromagnetic interference (EMI) control options relative to the physical design impacts for this power system, composed of 3 basic electrical elements. They are (1) the Stirling Power Convertor with its linear alternator, (2) the power switching and control electronics to convert the 90 V, 80 Hz alternator output to DC for the use of the spacecraft, and (3) the interconnecting wiring including any instrumentation to monitor and control items 1 and 2.

  19. SDTM - SYSTEM DESIGN TRADEOFF MODEL FOR SPACE STATION FREEDOM RELEASE 1.1

    NASA Technical Reports Server (NTRS)

    Chamberlin, R. G.

    1994-01-01

    Although extensive knowledge of space station design exists, the information is widely dispersed. The Space Station Freedom Program (SSFP) needs policies and procedures that ensure the use of consistent design objectives throughout its organizational hierarchy. The System Design Tradeoff Model (SDTM) produces information that can be used for this purpose. SDTM is a mathematical model of a set of possible designs for Space Station Freedom. Using the SDTM program, one can find the particular design which provides specified amounts of resources to Freedom's users at the lowest total (or life cycle) cost. One can also compare alternative design concepts by changing the set of possible designs, while holding the specified user services constant, and then comparing costs. Finally, both costs and user services can be varied simultaneously when comparing different designs. SDTM selects its solution from a set of feasible designs. Feasibility constraints include safety considerations, minimum levels of resources required for station users, budget allocation requirements, time limitations, and Congressional mandates. The total, or life cycle, cost includes all of the U.S. costs of the station: design and development, purchase of hardware and software, assembly, and operations throughout its lifetime. The SDTM development team has identified, for a variety of possible space station designs, the subsystems that produce the resources to be modeled. The team has also developed formulas for the cross consumption of resources by other resources, as functions of the amounts of resources produced. SDTM can find the values of station resources, so that subsystem designers can choose new design concepts that further reduce the station's life cycle cost. The fundamental input to SDTM is a set of formulas that describe the subsystems which make up a reference design. Most of the formulas identify how the resources required by each subsystem depend upon the size of the subsystem. Some of

  20. Report on the findings of the Japanese Investigative Team on US Space Station Design (Keidanren)

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The objectives, itinerary and results of the Japanese Investigative Team on U.S. Space Station Design (Keidanren), consisting of members of the Space Development Promotion Council and representatives of Japanese industries involved in Japan's space station development effort are presented. This team visited NASA facilities in February, 1985. The objectives of the study team are to gather information on preliminary design efforts toward space station planning in Japan and the promotion of Japanese space related industries, as well as the evaluation of the present status of space environment exploitation in the U.S. This report is intended to be a basic reference for government agencies and industry in addressing the course of action to be taken in the future development of Japan's space station participation.

  1. Life support and internal thermal control system design for the Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Humphries, R.; Mitchell, K.; Reuter, J.; Carrasquillo, R.; Beverly, B.

    1991-01-01

    A Review of the Space Station Freedom Environmental Control and Life Support System (ECLSS) as well as the Internal Thermal Control System (ITCS) design, including recent changes resulting from an activity to restructure the program, is provided. The development state of the original Space Station Freedom ECLSS through the restructured configuration is considered and the selection of regenerative subsystems for oxygen and water reclamation is addressed. A survey of the present ground development and verification program is given.

  2. 9 CFR 72.16 - Designated dipping stations to be approved by the Administrator, APHIS on recommendations of...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... CATTLE § 72.16 Designated dipping stations to be approved by the Administrator, APHIS on recommendations... points at which cattle of the quarantined area of the State in which said station is located may...

  3. 9 CFR 72.16 - Designated dipping stations to be approved by the Administrator, APHIS on recommendations of...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... CATTLE § 72.16 Designated dipping stations to be approved by the Administrator, APHIS on recommendations... points at which cattle of the quarantined area of the State in which said station is located may...

  4. 9 CFR 72.16 - Designated dipping stations to be approved by the Administrator, APHIS on recommendations of...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CATTLE § 72.16 Designated dipping stations to be approved by the Administrator, APHIS on recommendations... points at which cattle of the quarantined area of the State in which said station is located may...

  5. 9 CFR 72.16 - Designated dipping stations to be approved by the Administrator, APHIS on recommendations of...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... CATTLE § 72.16 Designated dipping stations to be approved by the Administrator, APHIS on recommendations... points at which cattle of the quarantined area of the State in which said station is located may...

  6. Space station Simulation Computer System (SCS) study for NASA/MSFC. Volume 4: Conceptual design report

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The Simulation Computer System (SCS) is the computer hardware, software, and workstations that will support the Payload Training Complex (PTC) at Marshall Space Flight Center (MSFC). The PTC will train the space station payload scientists, station scientists, and ground controllers to operate the wide variety of experiments that will be onboard the Space Station Freedom. In the first step of this task, a methodology was developed to ensure that all relevant design dimensions were addressed, and that all feasible designs could be considered. The development effort yielded the following method for generating and comparing designs in task 4: (1) Extract SCS system requirements (functions) from the system specification; (2) Develop design evaluation criteria; (3) Identify system architectural dimensions relevant to SCS system designs; (4) Develop conceptual designs based on the system requirements and architectural dimensions identified in step 1 and step 3 above; (5) Evaluate the designs with respect to the design evaluation criteria developed in step 2 above. The results of the method detailed in the above 5 steps are discussed. The results of the task 4 work provide the set of designs which two or three candidate designs are to be selected by MSFC as input to task 5-refine SCS conceptual designs. The designs selected for refinement will be developed to a lower level of detail, and further analyses will be done to begin to determine the size and speed of the components required to implement these designs.

  7. Crew factors in the design of the Space Station

    NASA Technical Reports Server (NTRS)

    Robinson, Judith L.

    1987-01-01

    The designing of Space Shuttle modules and equipment in order to provide a stimulating and efficient work atmosphere and a pleasant living environment is examined. The habitation module for the eight crew members is divided into four areas: ceiling, floor, port, and starboard. The module is to consist of crew quarters, a wardroom, a galley, a personal hygiene facility, a health maintenance facility, and stowage areas. There is a correlation between the function of the module and its location; for example the galley will be near the wardroom and the personal hygiene facility near the crew quarters. The designs of the equipment for crew accommodation and of the equipment to be maintained and repaired by the crew will be standarized. The design and functions of the crew and equipment restraints, crew mobility aids, racks to contain equipment, and functional units are described.

  8. Design of a photovoltaic central power station: flat-plate array

    SciTech Connect

    Not Available

    1984-02-01

    A design for a photovoltaic central power station using fixed flat-panel arrays has been developed. The 100 MW plant is assumed to be located adjacent to the Saguaro Power Station of Arizona Public Service. The design assumes high-efficiency photovoltaic modules using dendritic web cells. The modules are arranged in 5 MW subfields, each with its own power conditioning unit. The photovoltaic output is connected to the existing 115 kV utility switchyard. The site specific design allows detailed cost estimates for engineering, site preparation, and installation. Collector and power conditioning costs have been treated parametrically.

  9. International Space Station EXPRESS Pallet. Ground Demonstration Baseline Design Review

    NASA Technical Reports Server (NTRS)

    Schaffer, James R.

    1995-01-01

    This publication is comprised of the viewgraphs from the presentations of the EXPRESS Pallet Baseline Design Review meeting held July 20, 1995. Individual presentations addressed general requirements and objectives; mechanical, electrical, and data systems; software; operations and KSC (Kennedy Space Center) integration; payload candidates; thermal considerations; ground vs. flight demo; and recommended actions.

  10. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2004-01-01

    During the period October 1, 2003-December 31, 2003, Allegheny Energy Supply Co., LLC (Allegheny) continued with demonstration operations at the Willow Island Generating Station and improvements to the Albright Generating Station cofiring systems. The demonstration operations at Willow Island were designed to document integration of biomass cofiring into commercial operations, including evaluating new sources of biomass supply. The Albright improvements were designed to increase the resource base for the projects, and to address issues that came up during the first year of operations. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations.

  11. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2003-07-01

    During the period April 1, 2003--June 30, 2003, Allegheny Energy Supply Co., LLC (Allegheny) proceeded with demonstration operations at the Willow Island Generating Station and improvements to the Albright Generating Station cofiring systems. The demonstration operations at Willow Island were designed to document integration of biomass cofiring into commercial operations. The Albright improvements were designed to increase the resource base for the projects, and to address issues that came up during the first year of operations. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations.

  12. Design and experiment study of compact circular-rectangular waveguide mode converter

    NASA Astrophysics Data System (ADS)

    Zhao, Xuhao; Yuan, Chengwei; Zhang, Qiang; Zhao, Lishan

    2016-07-01

    A compact mode converter that transforms TM01 circular waveguide mode to TE10 rectangular waveguide mode is investigated. It consists of a circular waveguide with a short circuit terminal and a rectangular waveguide which is perpendicular to the circular waveguide. Simulation results show that conversion efficiency of the mode converter is about 99.8% at central frequency of 1.75 GHz, and the total return loss is approximately -30 dB. The experimental results are well consistent with the computer simulation, which demonstrates the feasibility and high power handling capacity of the mode converter.

  13. From the nurses' station to the health team hub: how can design promote interprofessional collaboration?

    PubMed

    Gum, Lyn Frances; Prideaux, David; Sweet, Linda; Greenhill, Jennene

    2012-01-01

    Interprofessional practice implies that health professionals are able to contribute patient care in a collaborative environment. In this paper, it is argued that in a hospital the nurses' station is a form of symbolic power. The term could be reframed as a "health team hub," which fosters a place for communication and interprofessional working. Studies have found that design of the Nurses' Station can impact on the walking distance of hospital staff, privacy for patients and staff, jeopardize patient confidentiality and access to resources. However, no studies have explored the implications of nurses' station design on interprofessional practice. A multi-site collective case study of three rural hospitals in South Australia explored the collaborative working culture of each hospital. Of the cultural concepts being studied, the physical design of nurses' stations and the general physical environment were found to have a major influence on an effective collaborative practice. Communication barriers were related to poor design, lack of space, frequent interruptions and a lack of privacy; the name "nurses' station" denotes the space as the primary domain of nurses rather than a workspace for the healthcare team. Immersive work spaces could encourage all members of the healthcare team to communicate more readily with one another to promote interprofessional collaboration. PMID:22233364

  14. Design and Performance of the Acts Gigabit Satellite Network High Data-Rate Ground Station

    NASA Technical Reports Server (NTRS)

    Hoder, Doug; Kearney, Brian

    1995-01-01

    The ACTS High Data-Rate Ground stations were built to support the ACTS Gigabit Satellite Network (GSN). The ACTS GSN was designed to provide fiber-compatible SONET service to remote nodes and networks through a wideband satellite system. The ACTS satellite is unique in its extremely wide bandwidth, and electronically controlled spot beam antennas. This paper discusses the requirements, design and performance of the RF section of the ACTS High Data-Rate Ground Stations and constituent hardware. The ACTS transponder systems incorporate highly nonlinear hard limiting. This introduced a major complexity in to the design and subsequent modification of the ground stations. A discussion of the peculiarities of the A CTS spacecraft transponder system and their impact is included.

  15. Design and operation of a Loran-C time reference station

    NASA Technical Reports Server (NTRS)

    Putkovich, K.

    1974-01-01

    Some of the practical questions that arise when one decides to use Loran-C in a time reference system are explored. An extensive effort is made to provide basic, practical information on establishing and operating a reference station. Four areas were covered: (1) the design, configuration and operational concepts which should be considered prior to establishing and operating a reference station using Loran-C, (2) the options and tradeoffs available regarding capabilities, cost, size, versatility, ease of operation, etc., that are available to the designer, (3) what measurements are made, how they are made and what they mean, and (4) the experience the U.S. Naval Observatory Time Service Division has had in the design and operation of such stations.

  16. Design, processing, and testing of lsi arrays for space station

    NASA Technical Reports Server (NTRS)

    Lile, W. R.; Hollingsworth, R. J.

    1972-01-01

    The design of a MOS 256-bit Random Access Memory (RAM) is discussed. Technological achievements comprise computer simulations that accurately predict performance; aluminum-gate COS/MOS devices including a 256-bit RAM with current sensing; and a silicon-gate process that is being used in the construction of a 256-bit RAM with voltage sensing. The Si-gate process increases speed by reducing the overlap capacitance between gate and source-drain, thus reducing the crossover capacitance and allowing shorter interconnections. The design of a Si-gate RAM, which is pin-for-pin compatible with an RCA bulk silicon COS/MOS memory (type TA 5974), is discussed in full. The Integrated Circuit Tester (ICT) is limited to dc evaluation, but the diagnostics and data collecting are under computer control. The Silicon-on-Sapphire Memory Evaluator (SOS-ME, previously called SOS Memory Exerciser) measures power supply drain and performs a minimum number of tests to establish operation of the memory devices. The Macrodata MD-100 is a microprogrammable tester which has capabilities of extensive testing at speeds up to 5 MHz. Beam-lead technology was successfully integrated with SOS technology to make a simple device with beam leads. This device and the scribing are discussed.

  17. Conceptual design and integration of a space station resistojet propulsion assembly

    NASA Technical Reports Server (NTRS)

    Tacina, Robert R.

    1987-01-01

    The resistojet propulsion module is designed as a simple, long life, low risk system offering operational flexibility to the space station program. It can dispose of a wide variety of typical space station waste fluids by using them as propellants for orbital maintenance. A high temperature mode offers relatively high specific impulse with long life while a low temperature mode can propulsively dispose of mixtures that contain oxygen or hydrocarbons without reducing thruster life or generating particulates in the plume. A low duty cycle and a plume that is confined to a small aft region minimizes the impacts on the users. Simple interfaces with other space station systems facilitate integration. It is concluded that there are no major obstacles and many advantages to developing, installing, and operating a resistojet propulsion module aboard the Initial Operational Capability (IOC) space station.

  18. Conceptual design and integration of a Space Station resistojet propulsion assembly

    NASA Technical Reports Server (NTRS)

    Tacina, R. R.

    1987-01-01

    The resistojet propulsion module is designed as a simple, long life, low risk system offering operational flexibility to the space station program. It can dispose of a wide variety of typical space station waste fluids by using them as propellants for orbital maintenance. A high temperature mode offers relatively high specific impulse with long life while a low temperature mode can propulsively dispose of mixtures that contain oxygen or hydrocarbons without reducing thruster life or generating particulates in the plume. A low duty cycle and a plume that is confined to a small aft region minimizes the impacts on the users. Simple interfaces with other space station systems facilitate integration. It is concluded that there are no major obstacles and many advantages to developing, installing, and operating a resistojet propulsion module aboard the Initial Operational Capability (IOC) space station.

  19. Analysis, design and implementation of an interleaved three-level PWM DC/DC ZVS converter

    NASA Astrophysics Data System (ADS)

    Lin, Bor-Ren; Liu, Chien-Hung

    2016-02-01

    This paper presents a new parallel three-level soft switching pulse-width modulation (PWM) converter. The proposed converter has two circuit cells operated by the interleaved PWM modulation. Thus, the ripple currents at input and output sides are reduced. Each circuit cell has two three-level zero voltage switching circuits sharing the same power switches. Therefore, the current and power rating of the secondary side components are reduced. Current double rectifier topology is selected on the secondary side to decrease output ripple current. The main advantages of the proposed converter are soft switching of power switches, low ripple current on the output side and low-voltage rating of power switches for medium-power applications. Finally, the performance of the proposed converter is verified by experiments with 1 kW prototype circuit.

  20. Space station integrated wall design and penetration damage control

    NASA Technical Reports Server (NTRS)

    Coronado, A. R.; Gibbins, M. N.; Wright, M. A.; Stern, P. H.

    1987-01-01

    A methodology was developed to allow a designer to optimize the pressure wall, insulation, and meteoroid/debris shield system of a manned spacecraft for a given spacecraft configuration and threat environment. The threat environment consists of meteoroids and orbital debris, as specified for an arbitrary orbit and expected lifetime. An overall probability of no penetration is calculated, as well as contours of equal threat that take into account spacecraft geometry and orientation. Techniques, tools, and procedures for repairing an impacted and penetrated pressure wall were developed and tested. These techniques are applied from the spacecraft interior and account for the possibility of performing the repair in a vacuum. Hypervelocity impact testing was conducted to: (1) develop and refine appropriate penetration functions, and (2) determine the internal effects of a penetration on personnel and equipment.

  1. Advanced ceramic fabric body mounted radiator for Space Station Freedom Phase O design

    SciTech Connect

    Webb, B.J.; Antoniak, Z.I.; Pauley, K.A.

    1990-06-01

    A body mounted radiator concept constructed of advanced ceramic fabric materials for use with the Phase 0 design of Space Station Freedom is described. The radiator is expected to weigh between 1.4 and 3.5 kg/m{sup 2} of single sided radiating surface, use ammonia working fluid, be highly deployable, and exhibit good reliability characteristics. This compares well with the 11.8 kg/m{sup 2} for two sided radiators proposed for the current space station design.

  2. EVA operational guidelines and considerations for use during the Space Station Freedom design review process

    NASA Technical Reports Server (NTRS)

    Trevino, Robert

    1992-01-01

    The EVA hardware interfaces, standards, and considerations are examined, as are guidelines that EVA operations engineer will use when reviewing the design packages from the EVA operational point of view. By utilizing both the EVA and robotics interfaces standards, design requirements, and the EVA operational guidelines and considerations, the Space Station Freedom program design can be more cost effective in the long term and also more compatible and friendly for on-orbit assembly and on-orbit maintenance and repair.

  3. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2003-04-30

    During the period January 1, 2003--March 31, 2003, Allegheny Energy Supply Co., LLC (Allegheny) proceeded with improvements to both the Willow Island and Albright Generating Station cofiring systems. These improvements were designed to increase the resource base for the projects, and to address issues that came up during the first year of operations. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations.

  4. Design Methodology And Qualification Tests Results For A Highly Integrated And Space Qualified Point Of Load Converter

    NASA Astrophysics Data System (ADS)

    Vassal, Marie-Cecile; Dubus, Patrick; Fiant, Nicolas

    2011-10-01

    3D Plus developed a highly miniaturized and Space qualified Point of Load (POL) Converter to power modern fast digital electronics such as ASICs, FPGAs and Memory devices that require low voltages with a high precision regulation and excellent dynamic performances under large load transients. The POL Converter is hardened by design thanks to specific radiation effects mitigation techniques and space design de-rating rules. It is built with a space qualified 3D System-In-Package (SIP) technology and embeds 113 add-on parts spread over 3 stacked layers. Thanks to the unique 3D Plus technology, the device size is limited to 25 x 26.5 x 10 mm. This paper discuss the converter topology trade-offs and highlight some final design solutions implemented to achieve the best compromise between efficiency, dynamic performance, protection/flexibility and radiation hardening level. The product implementation and its electrical test results are presented. Also, the radiation hardening strategy, the Total Ionizing Dose (TID), Single Event Latch-up (SEL) and Single Event Effect (SEE) test methodology and the results are described. A special focus is done on SEE tests for which the POL Converter was rebuilt with "decap" add-on parts and exposed under the beam for detailed SEE behavior measurements.

  5. Magnetorheological converters

    SciTech Connect

    Zal'tsgendler, E.A.; Kolomentsev, A.V.; Kordonskii, V.I.; Madorskii, L.S.

    1986-04-01

    The authors study the problems of constructing an electrohydraulic converter functioning based on the magnetoheological effect: the magnetorheological throttle (MR throttle). Requirements are listed that must be taken into account in developing the MR throttle. The paper attempts to calculate the flow-rate characteristics of the MR throttle. The rheological equation which describes sufficiently the mechanical properties of the magnetoheological suspensions is presented. The paper examines the calculation of the magnetic inductor for the example of a toroidal core with a gap, which simultaneously functions as the slot throttling channel. The use of the designs described enabled the development of bridge converters, which have a flat amplitude-frequency characteristic in the range 200-250 Hz and which have good energy indicators. Typical experimental logarithmic amplitude-frequency and phase-frequency characteristics of a bridge converter are shown.

  6. From 2001 to 1994: Political environment and the design of NASA's Space Station system

    NASA Technical Reports Server (NTRS)

    Fries, Sylvia Doughty

    1988-01-01

    The U.S. civilian space station, a hope of numerous NASA engineers since before the agency was founded in 1958 and promoted by NASA as the country's 'next logical step' into space, provides an excellent case study of the way public-sector research and development agencies continuously redefine new technologies in the absence of the market discipline that governs private-sector technological development. The number of space station design studies conducted since 1959, both internally by NASA or contracted by the agency to the aerospace industry, easily exceeds a hundred. Because of this, three clearly distinguishable examples are selected from the almost thirty-year history of space station design in NASA. Together these examples illustrate the difficulty of defining a new technological system in the public sector as that system becomes increasingly subject, for its development, to the vagaries of federal research and development politics.

  7. Preliminary design of a cargo return vehicle for Space Station Freedom

    NASA Astrophysics Data System (ADS)

    Cook, Stephen; Vano, Andrew

    1990-09-01

    The design of an unmanned, reusable cargo return vehicle (CRV) incorporated as a class project at the University of Minnesota under NASA auspices is presented. Two configurations are considered, a winged and a biconic with a parafoil advanced recovery system. Three inline liquid rocket boosters would propel the CRV into a low earth orbit with onboard orbital maneuvering system engines used to reach station orbit and dock to the station. The main objective of the courses was to develop the design skills of the students while allowing them to work together in teams with NASA and industry engineers on a specific NASA project. The final conclusion of the study was that the winged CRV was the best vehicle for space station resupply.

  8. Robust H infinity control design for the space station with structured parameter uncertainty

    NASA Technical Reports Server (NTRS)

    Byun, Kuk-Whan; Wie, Bong; Geller, David; Sunkel, John

    1992-01-01

    A robust H-infinity control design methodology and its application to a Space Station attitude and momentum control problem are presented. This new approach incorporates nonlinear multi-parameter variations in the state-space formulation of H-infinity control theory. An application of this robust H-infinity control synthesis technique to the Space Station control problem yields a remarkable result in stability robustness with respect to the moments-of-inertia variation of about 73% in one of the structured uncertainty directions. The performance and stability of this new robust H-infinity controller for the Space Station are compared to those of other controllers designed using a standard linear-quadratic-regulator synthesis technique.

  9. Robust H(infinity) control design for the Space Station with structured parameter uncertainty

    NASA Technical Reports Server (NTRS)

    Byun, Kuk-Whan; Wie, Bong; Geller, David; Sunkel, John

    1990-01-01

    A robust H(infinity) control design methodology and its application to a Space Station attitude and momentum control problem are presented. This new approach incorporates nonlinear multiparameter variations in the state-space formulation of H(infinity) control theory. An application of this robust control synthesis technique tothe Space Station control problem yields a remarkable result in stability robustness with respect to the moments-of-inertia variation of about 73 percent in one of the structured uncertainty directions. The performance and stability of this new robust H(infinity) controller for the Space Station are compared to those of other controllers designed using a standard linear-quadratic-regulator synthesis technique.

  10. Multifunctional gold nanoparticles for targeted imaging of angiotensin converting enzyme design, characterization, and application

    NASA Astrophysics Data System (ADS)

    Ghann, William Emmanuel

    Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality in the United States with approximately one in every three death being attributed to these diseases. The overarching problem with heart diseases is that once a person has suffered from an attack, there is a high likelihood of a recurrent attack. According to the American Heart Association, approximately 785,000 Americans per year suffer from heart attacks for the first time and about half of the aforementioned experience an ensuing attack. The second attack is often fatal, and therefore relapse prevention is crucial. One of the possible ways of averting the recurrence of such an attack is through the precise monitoring of the preceding biomarkers or risk indicators. This project encompasses the design, synthesis, characterization, and application of nanoparticle-based contrast agents that can potentially be used in the monitoring of the reemergence of a biomarker expressed after a person has suffered myocardial infarction. The overexpression of this biomarker, angiotensin converting enzyme (ACE), is also associated with development of cardiac and pulmonary fibrosis. To this end, highly concentrated gold nanoparticles have been synthesized and conjugated to Lisinopril, an ACE inhibitor, for the molecular imaging of ACE using X-ray CT. Various stabilities studies were conducted to verify the resistance of this gold nanoprobe in biological relevant media. They have also been successfully used in X-ray computed tomography to visualize tissue ACE and thus render them potentially versatile in the monitoring of cardiovascular diseases. An MRI tag was also conjugated to the gold nanoparticle affording the opportunity for bimodal imaging of ACE. This contrast agent could further be used for the quantification using K-edge CT of the relationship between the amount of the said marker and its role in predicting the possibility of a successive heart attack. The prepared nanoparticle-based contrast

  11. Concept design, modeling and station-keeping attitude control of an earth observation platform

    NASA Astrophysics Data System (ADS)

    Yang, Yueneng; Wu, Jie; Zheng, Wei

    2012-11-01

    The stratosphere airship provides a unique and promising platform for earth observation. Researches on the project design and control scheme for earth observation platforms are still rarely documented. Nonlinear dynamics, model uncertainties, and external disturbances contribute to the difficulty in maneuvering the stratosphere airship. A key technical challenge for the earth observation platform is station keeping, or the ability to remain fixed over a geo-location. This paper investigates the conceptual design, modeling and station-keeping attitude control of the near-space earth observation platform. A conceptual design of the earth observation platform is presented. The dynamics model of the platform is derived from the Newton-Euler formulation, and the station-keeping control system of the platform is formulated. The station-keeping attitude control approach for the platform is proposed. The multi-input multi-output nonlinear control system is decoupled into three single-input single-output linear subsystems via feedback linearization, the attitude controller design is carried out on the new linear systems using terminal sliding mode control, and the global stability of the closed-loop system is proven by using the Lyapunov theorem. The performance of the designed control system is simulated by using the variable step Runge-Kutta integrator. Simulation results show that the control system tracks the commanded attitude with an error of zero, which verify the effectiveness and robustness of the designed control system in the presence of parametric uncertainties. The near-space earth observation platform has several advantages over satellites, such as high resolution, fast to deploy, and convenient to retrieve, and the proposed control scheme provides an effective approach for station-keeping attitude control of the earth observation platform.

  12. Design, definition, and manufacture participation for the SAR Electronic Power Converter (EPC) breadboard

    NASA Astrophysics Data System (ADS)

    Klaassens, J. B.; Schwarz, F. C.

    1983-05-01

    A principle of fine regulation applied to the high voltage line supplying a pulsed load (radar tube) is presented. The high voltage power supply system is a combination of a single series resonant converter and a capacitor multiplier in the output stages. The electronic power conversion system uses a Schwarz converter employing a series resonant circuit for the transfer and control of power. An internal frequency of 35 kHz enhances the power density of the converter model. This model provides 16 kV for the helix-cathode circuit of a klystron with an accuracy of 0.5 per mill and 11 kV for the collector-cathode circuit with an accuracy of 5%. Experiments suggest that the improved power supply should alleviate problems associated with high voltage transformers and ensure the high accuracy required for the voltage control for the helix-cathode circuit to avoid distortion in the returning signal of a spaceborne radar system.

  13. Design considerations for a thermophotovoltaic energy converter using heat pipe radiators

    SciTech Connect

    Ashcroft, J.; DePoy, D.

    1997-06-01

    The purpose of this paper is to discuss concepts for using high temperature heat pipes to transport energy from a heat source to a thermophotovoltaic (TPV) converter. Within the converter, the condenser portion of each heat pipe acts as a photon radiator, providing a radiant flux to adjacent TPV cells, which in turn create electricity. Using heat pipes in this way could help to increase the power output and the power density of TPV systems. TPV systems with radiator temperatures in the range of 1,500 K are expected to produce as much as 3.6 W/cm{sup 3} of heat exchanger volume at an efficiency of 20% or greater. Four different arrangements of heat pipe-TPV energy converters are considered. Performance and sizing calculations for each of the concepts are presented. Finally, concerns with this concept and issues which remain to be considered are discussed.

  14. Project EGRESS: The design of an assured crew return vehicle for the space station

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Keeping preliminary studies by NASA in mind, an Assured Crew Return Vehicle (ACRV) was developed. The system allows the escape of one or more crew members from Space Station Freedom in case of emergency. The design of the vehicle addresses propulsion, orbital operations, reentry, landing and recovery, power and communication, and life support. In light of recent modifications in Space Station design, Project EGRESS (Earthbound Guaranteed ReEntry from Space Station) pays particular attention to its impact on Space Station operations, interfaces and docking facilities, and maintenance needs. A water landing, medium lift vehicle was found to best satisfy project goals of simplicity and cost efficiency without sacrificing the safety and reliability requirements. With a single vehicle, one injured crew member could be returned to Earth with minimal pilot involvement. Since the craft is capable of returning up to five crew members, two such permanently docked vehicles would allow full evacuation of the Space Station. The craft could be constructed entirely with available 1990 technology and launched aboard a shuttle orbiter.

  15. An investigation of the needs and the design of an orbiting space station with growth capabilities

    NASA Technical Reports Server (NTRS)

    Dossey, J. R.; Trotti, G.

    1977-01-01

    An architectural approach to the evolutionary growth of an orbiting space station from a small manned satellite to a fully independent, self-sustainable space colony facility is presented. Social and environmental factors, ease of transportation via the space shuttle, and structural design are considered.

  16. Implications of Privacy Needs and Interpersonal Distancing Mechanisms for Space Station Design

    NASA Technical Reports Server (NTRS)

    Harrison, A. A.; Sommer, R.; Struthers, N.; Hoyt, K.

    1986-01-01

    The literature on privacy needs, personal space, interpersonal distancing, and crowding is reveiwed with special reference to spaceflight and spaceflight analogous conditions. A quantitative model is proposed for understanding privacy, interpersonal distancing, and performance. The implications for space station design is described.

  17. 76 FR 40345 - Information on Surplus Land at a Military Installation Designated for Disposal: Naval Station...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-08

    ... (the Act). On May 10, 2006, Navy published a Notice in the Federal Register (71 FR 27237 and 27238... Department of the Navy Information on Surplus Land at a Military Installation Designated for Disposal: Naval Station Pascagoula, Mississippi AGENCY: Department of the Navy, DoD. ACTION: Notice. SUMMARY: This...

  18. Natural environment design criteria for the space station program definition phase

    NASA Technical Reports Server (NTRS)

    Vaughan, W. W.

    1984-01-01

    The natural environment design criteria requirements for use in the Space Station and its Elements (SSPE) definition phase studies are presented. The atmospheric dynamic and thermodynamic environments, meteoroids, radiation, physical constants are addressed. It is intended to enable all groups involved in the definition phase studies to proceed with a common and consistent set of natural environment criteria requirements.

  19. Mechanical design of a low concentration ratio solar array for a space station application

    NASA Technical Reports Server (NTRS)

    Biss, M. S.; Hsu, L.

    1983-01-01

    This paper describes a preliminary study and conceptual design of a low concentration ratio solar array for a space station application with approximately a 100 kW power requirement. The baseline design calls for a multiple series of inverted, truncated, pyramidal optical elements with a geometric concentration ratio (GCR) of 6. It also calls for low life cycle cost, simple on-orbit maintainability, 1984 technology readiness date, and gallium arsenide (GaAs) of silicon (Si) solar cell interchangeability. Due to the large area needed to produce the amount of power required for the baseline space station, a symmetrical wing design, making maximum use of the commonality of parts approach, was taken. This paper will describe the mechanical and structural design of a mass-producible solar array that is very easy to tailor to the needs of the individual user requirement.

  20. The space station: Key to living in space. [design concepts for Manned Orbiting Laboratory and Skylab

    NASA Technical Reports Server (NTRS)

    Lord, D. R.

    1973-01-01

    Design and scientific equipment for the Manned Orbiting Laboratory and Skylab are elaborated. Multideck designs accommodate both zero gravity and artificial gravity conditions as well as a core module potentially useful as a planetary mission module for a 12-man crew. Artificial gravity approaches consider assembly rotation and differential spin rates for the various decks. Counterrotation systems are projected to go from a station to a 50-man space base concept.

  1. Truss Climbing Robot for Space Station: Design, Analysis, and Motion Control

    NASA Astrophysics Data System (ADS)

    Chung, Wing Kwong

    The application of space robots has become more popular in performing tasks such as Intra and Extra Vehicular Activities (EVA) in Low Earth Orbit. For EVA, space robots were always designed as a chain-like manipulator with a joint configuration similar to on the earth robotic arm. Based on their joint configuration, they can be classified into two main categories. The first one is the six degrees of freedom (DOF) robotic arm including Shuttle Remote Manipulator System (SRMS), Engineering Test Satellite No. 7 (ETS-VII), the Main Arm (MA) and the Small Fine Arm (SFA) of Module Remote Manipulator System (JEMRMS). The other group is the seven-DOF space robotic arm which includes European Robotic Arm (ERA) and Space Station Remote Manipulator System (SSRMS), or Canadarm2. They not only perform manipulation tasks, but also be able to navigate on the exterior of the International Space Station (ISS). In a free floating environment, motions of a space robotic arm cause the attitude change of a space station because of their dynamic coupling effect. Hence, the stabilization of the space station attitude is important to maintain the electrical energy generated by the solar panels and the signal strength for communication. Most of research in this area focuses on the motion control of a space manipulator through the study of Generalized Jacobian Matrix. Little research has been conducted specifically on the design of locomotion mechanism of a space manipulator. This dissertation proposes a novel methodology for the locomotion on a space station which aims to lower the disturbance on a space station. Without modifying the joint configuration of conventional space manipulators, the use of a new gripping mechanism is proposed which combines the advantages of active wheels and conventional grippers. To realize the proposed gripping mechanism, this dissertation also presents the design of a novel frame climbing robot (Frambot) which is equipped with the new gripping mechanism

  2. A novel design of DC-AC electrical machine rotary converter for hybrid solar and wind energy applications

    NASA Astrophysics Data System (ADS)

    Mohammed, K. G.; Ramli, A. Q.; Amirulddin, U. A. U.

    2013-06-01

    This paper proposes the design of a new bi-directional DC-AC rotary converter machine to convert a d.c. voltage to three-phase voltage and vice-versa using a two-stage energy conversion machine. The rotary converter consists of two main stages which are combined into single frame. These two stages are constructed from three main electromagnetic components. The first inner electromagnetic component represents the input stage that enables the DC power generated by solar energy from photo-voltaic cells to be transformed by the second and third components electro-magnetically to produce multi-phase voltages at the output stage. At the same time, extra kinetic energy from wind, which is sufficiently available, can be added to existing torque on the second electromagnetic component. Both of these input energies will add up to the final energy generated at the output terminals. Therefore, the machine will be able to convert solar and wind energies to the output terminals simultaneously. If the solar energy is low, the available wind energy will be able to provide energy to the output terminals and at the same time charges the batteries which are connected as backup system. At this moment, the machine behaves as wind turbine. The energy output from the machine benefits from two energy sources which are solar and wind. At night when the solar energy is not available and also the load is low, the wind energy is able to charge the batteries and at the same time provides output electrical power to the remaining the load. Therefore, the proposed system will have high usage of available renewable energy as compared to separated wind or solar systems. MATLAB codes are used to calculate the required dimensions, the magnetic and electrical circuits parameters to design of the new bi-directional rotary converter machine.

  3. An intelligent control and virtual display system for evolutionary space station workstation design

    NASA Technical Reports Server (NTRS)

    Feng, Xin; Niederjohn, Russell J.; Mcgreevy, Michael W.

    1992-01-01

    Research and development of the Advanced Display and Computer Augmented Control System (ADCACS) for the space station Body-Ported Cupola Virtual Workstation (BP/VCWS) were pursued. The potential applications were explored of body ported virtual display and intelligent control technology for the human-system interfacing applications is space station environment. The new system is designed to enable crew members to control and monitor a variety of space operations with greater flexibility and efficiency than existing fixed consoles. The technologies being studied include helmet mounted virtual displays, voice and special command input devices, and microprocessor based intelligent controllers. Several research topics, such as human factors, decision support expert systems, and wide field of view, color displays are being addressed. The study showed the significant advantages of this uniquely integrated display and control system, and its feasibility for human-system interfacing applications in the space station command and control environment.

  4. Design, construction and utilization of a space station assembled from 5-meter erectable struts

    NASA Technical Reports Server (NTRS)

    Mikulas, M. M., Jr.; Bush, H. G.

    1986-01-01

    Presented are the primary characteristics of the 5-meter erectable truss designated for the space station. The relatively large 5-meter truss dimension was chosen to provide a deep beam for high bending stiffness yet provide convenient mounting locations for space shuttle cargo bay size payloads which are 14.5 ft. (4.4 m) in diameter. Truss nodes and quick-attachment erectable joints are described which provide for evolutionary three-dimensional growth and for simple maintenance and repair. A mobile remote manipulator system is described which is provided to assist in station construction and maintenance. A discussion is also presented of the construction of the space station and the associated EVA time.

  5. Advanced EVA system design requirements study: EVAS/space station system interface requirements

    NASA Technical Reports Server (NTRS)

    Woods, T. G.

    1985-01-01

    The definition of the Extravehicular Activity (EVA) systems interface requirements and accomodations for effective integration of a production EVA capability into the space station are contained. A description of the EVA systems for which the space station must provide the various interfaces and accomodations are provided. The discussion and analyses of the various space station areas in which the EVA interfaces are required and/or from which implications for EVA system design requirements are derived, are included. The rationale is provided for all EVAS mechanical, fluid, electrical, communications, and data system interfaces as well as exterior and interior requirements necessary to facilitate EVA operations. Results of the studies supporting these discussions are presented in the appendix.

  6. Design and assembly sequence analysis of option 3 for CETF reference space station

    NASA Technical Reports Server (NTRS)

    Garrett, L. Bernard; Andersen, Gregory C.; Hall, John B., Jr.; Allen, Cheryl L.; Scott, A. D., Jr.; So, Kenneth T.

    1987-01-01

    A design and assembly sequence was conducted on one option of the Dual Keel Space Station examined by a NASA Critical Evaluation Task Force to establish viability of several variations of that option. A goal of the study was to produce and analyze technical data to support Task Force decisions to either examine particular Option 3 variations in more depth or eliminate them from further consideration. An analysis of the phasing assembly showed that use of an Expendable Launch Vehicle in conjunction with the Space Transportation System (STS) can accelerate the buildup of the Station and ease the STS launch rate constraints. The study also showed that use of an Orbital Maneuvering Vehicle on the first flight can significantly benefit Station assembly and, by performing Station subsystem functions, can alleviate the need for operational control and reboost systems during the early flights. In addition to launch and assembly sequencing, the study assessed stability and control, and analyzed node-packaging options and the effects of keel removal on the structural dynamics of the Station. Results of these analyses are presented and discussed.

  7. Spaceborne computer executive routine functional design specification. Volume 2: Computer executive design for space station/base

    NASA Technical Reports Server (NTRS)

    Kennedy, J. R.; Fitzpatrick, W. S.

    1971-01-01

    The computer executive functional system design concepts derived from study of the Space Station/Base are presented. Information Management System hardware configuration as directly influencing the executive design is reviewed. The hardware configuration and generic executive design requirements are considered in detail in a previous report (System Configuration and Executive Requirements Specifications for Reusable Shuttle and Space Station/Base, 9/25/70). This report defines basic system primitives and delineates processes and process control. Supervisor states are considered for describing basic multiprogramming and multiprocessing systems. A high-level computer executive including control of scheduling, allocation of resources, system interactions, and real-time supervisory functions is defined. The description is oriented to provide a baseline for a functional simulation of the computer executive system.

  8. Impacting Space Station Freedom design with operations and safety requirements - An availability process

    NASA Technical Reports Server (NTRS)

    Garegnani, Jerry J.; Schondorf, Steven Y.

    1990-01-01

    The unusually long mission duration of Space Station Freedom leads to operations costs that have significant impacts on life-cycle cost relative to previous manned space programs. Maintaining an affordable program requires that operations costs be considered throughout the design process. An appropriate means of impacting the design with operations concerns is to specify requirements that ensure operational effectiveness when implemented. The Space Station Freedom Program has developed a process defining such requirements. It focuses on specifying functional profiles and allocating resources such that designers gain a better understanding of the operational envelope in which their systems must perform. This paper examines the details of the process, where it came from, and why it is effective.

  9. Multi-stage design of an optimal momentum management controller for the Space Station

    NASA Technical Reports Server (NTRS)

    Sunkel, J. W.; Shieh, L. S.

    1990-01-01

    This paper presents a multistage design scheme for determining an optimal control-moment-gyro momentum-management and attitude-control system for the Space Station Freedom. The Space Station equations of motion are linearized and block-decomposed into two block-decoupled subsystems using the matrix-sign algorithm. A sequential procedure is utilized for designing a linear-quadratic regulator for each subsystem, which optimally places the eigenvalues of the closed-loop subsystem in the region of an open sector, bounded by lines inclined at + or - pi/2k (for k = 2 or 3) from the negative real axis, and the left-hand side of a line parallel to the imaginary axis in the s-plane. Simulation results are presented to compare the resultant designs.

  10. Bio-Medical Factors and External Hazards in Space Station Design

    NASA Technical Reports Server (NTRS)

    Olling, E. H.

    1966-01-01

    The design of space-station configurations is influenced by many factors. Probably the most demanding and critical are the biomedical and external hazards requirements imposed to provide the proper environment and supporting facilities for the crew and the adequate protective measures necessary to provide a configuration'in which the crew can live and work efficiently in relative comfort and safety. The major biomedical factors, such as physiology, psychology, nutrition, personal hygiene, waste management, and recreation, all impose their own peculiar requirements. The commonality and integration of these requirements demand the utmost ingenuity and inventiveness be exercised in order to achieve effective configuration compliance. The relationship of biomedical factors for the internal space-station environment will be explored with respect to internal atmospheric constituency, atmospheric pressure levels, oxygen positive pressure, temperature, humidity, CO2 concentration, and atmospheric contamination. The range of these various parameters and the recommended levels for design use will be analyzed. Requirements and criteria for specific problem areas such as zero and artificial gravity and crew private quarters will be reviewed and the impact on the design of representative solutions will be presented. In the areas of external hazards, the impact of factors such as meteoroids, radiation, vacuum, temperature extremes, and cycling on station design will be evaluated. Considerations with respect to operational effectiveness and crew safety will be discussed. The impact of such factors on spacecraft design to achieve acceptable launch and reentry g levels, crew rotation intervals, etc., will be reviewed.

  11. Design of a compact mode and polarization converter in three-dimensional photonic crystals.

    PubMed

    Wang, Jian; Qi, Minghao

    2012-08-27

    A mode and polarization converter is proposed and optimized for 3D photonic integrated circuits based on photonic crystals (PhCs). The device converts the index-guided TE mode of a W1 solid-core (SC) waveguide to the band-gap-guided TM mode of a W1 hollow-core (HC) waveguide in 3D PhCs, and vice versa. The conversion is achieved based on contra-directional mode coupling. For a 25 μm-long device, simulations show that the power conversion efficiency is over 98% across a wavelength range of 16 nm centered at 1550 nm, whereas the reflection remains below -20 dB. The polarization extinction ratio of the conversion is in principle infinitely high because both W1 waveguides operate in the single-mode regimes in this wavelength range. PMID:23037086

  12. Design and implementation of a novel synchronous-rectifier forward converter with improved performance

    NASA Astrophysics Data System (ADS)

    Liu, Tian-Hua; Wang, Kuan-Sheng

    2010-08-01

    This article proposes two new methods for improving the performance of a synchronous-rectifier forward converter. A synchronous-rectifier converter produces a reverse current in the inductor due to the bidirectional characteristic of MOSFETs while the converter is turned off. This reverse current causes voltage spikes which may damage the power devices. This article proposes two methods to reduce the voltage spikes: method 1 and method 2. Method 1 uses the enable signal detection method. An enable signal is generated from the remote control of the system when the main power is turned off. Then, the proposed circuit of method 1 turns off the free-wheeling switch before the reverse current is produced. As a result, the voltage spike can be avoided. Method 2 uses a transformer winding to detect the turn-off time of the input power. Then, the circuit turns off the free-wheeling switch to break the resonant loop and end the reverse current. The cost analysis of method 1 and 2 is included. In addition, several experimental results are provided to validate the correctness and feasibility of the theoretical analysis.

  13. Progress in design of advanced LIDT station in HiLASE project

    NASA Astrophysics Data System (ADS)

    Vanda, Jan

    2015-01-01

    Laser induced damage threshold is a key component characteristic while building high-performance laser system, establishing maximum achievable energy and consequently average power of the laser. Reliable and stable laser sources are desirable both in academic and industrial areas. To assure these quality criteria, involved components have to be tested and proved at certain values. The goal of HiLASE project is to develop and provide such highly progressive laser systems, and consequently advance in related areas, as high-energy laser components. Together with laser system is developed LIDT station to provide necessary background for components reliability and later application potential for final beamlines. Such station, however, has to meet certain criteria as well, to ensure reliability of conducted measurements and credibility of obtained results. ISO 21254 standard series describes methods of damage detection and principles of ensuring reliability of damage threshold measurement. Nevertheless, unique nature of HiLASE lasers allows new approach, which makes design of proper measuring station state-of-the-art challenge. Following paper reports recent progress in design of laser induced damage threshold station developed within HiLASE project.

  14. Converting a C-130 Hercules into a Compound Helicopter: A Conceptual Design Study

    NASA Technical Reports Server (NTRS)

    Kottapalli, Anjaney P.; Harris, Franklin D.

    2010-01-01

    This study presents the performance and weight changes for a Compound C-130 as compared to the Baseline C-130H Hercules, using NDARC as the primary analysis tool. First, the C-130H was modeled within NDARC, from which performance at various conditions and a parametric weight statement were generated. Then, the C-130H NDARC file was modified to represent the Compound C-130, which was then put through the same performance analysis as the C-130H. A parametric weight statement was also calculated for the Compound C-130, which allowed for comparison to the C-130H. As part of the modeling of the Compound C-130, a Rotor Design Spreadsheet was created that would allow the direct calculation of the weight of the main rotors being added. Using composite materials led to considerable weight savings for both the rotor system and the hub weights. These weight savings are reflected in the NDARC Technology Factors which were determined to be 0.71 and 0.5 for the rotor blades and the hub/hinge system, respectively. Such Technology Factors suggest that using composites for other components could drastically lighten the Operating Empty Weight of the aircraft. The weight statements show the weights for each of the components on each aircraft. It is quite evident that the Compound C-130 has a higher Operating Empty Weight due to the addition of the two main rotors and a drive system to connect each engine group on the wing tips. Upon further analysis, the main weight driver is the drive system. While the main rotor/hub/hinge weight increase is to be expected, the weight increase due to the transmission drive and gear boxes are cause for concern. Unless a method can be found of reducing the weight of the drive system, the weight penalty makes the Compound a C-130 an inefficient aircraft in terms of payload/fuel capacity. Possible solutions are either off-loading some of the power requirements through the drive system or using composite materials in the construction of the drive system

  15. Space Station Furnace Facility. Volume 2: Requirements definition and conceptual design study

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Space Station Freedom Furnace (SSFF) Project is divided into two phases: phase 1, a definition study phase, and phase 2, a design and development phase. TBE was awarded a research study entitled, 'Space Station Furnace Facility Requirements Definition and Conceptual Design Study' on June 2, 1989. This report addresses the definition study phase only. Phase 2 is to be complete after completion of phase 1. The contract encompassed a requirements definition study and culminated in hardware/facility conceptual designs and hardware demonstration development models to test these conceptual designs. The study was divided into two parts. Part 1 (the basic part of the effort) encompassed preliminary requirements definition and assessment; conceptional design of the SSFF Core; fabrication of mockups; and preparation for the support of a conceptional design review (CoDR). Part 2 (the optional part of the effort) included detailed definition of the engineering and design requirements, as derived from the science requirements; refinement of the conceptual design of the SSFF Core; fabrication and testing of the 'breadboards' or development models; and preparation for and support of a requirements definition review.

  16. Space Station Furnace Facility. Volume 2: Requirements definition and conceptual design study

    NASA Astrophysics Data System (ADS)

    1992-05-01

    The Space Station Freedom Furnace (SSFF) Project is divided into two phases: phase 1, a definition study phase, and phase 2, a design and development phase. TBE was awarded a research study entitled, 'Space Station Furnace Facility Requirements Definition and Conceptual Design Study' on June 2, 1989. This report addresses the definition study phase only. Phase 2 is to be complete after completion of phase 1. The contract encompassed a requirements definition study and culminated in hardware/facility conceptual designs and hardware demonstration development models to test these conceptual designs. The study was divided into two parts. Part 1 (the basic part of the effort) encompassed preliminary requirements definition and assessment; conceptional design of the SSFF Core; fabrication of mockups; and preparation for the support of a conceptional design review (CoDR). Part 2 (the optional part of the effort) included detailed definition of the engineering and design requirements, as derived from the science requirements; refinement of the conceptual design of the SSFF Core; fabrication and testing of the 'breadboards' or development models; and preparation for and support of a requirements definition review.

  17. Computer-aided designing of automatic process control systems for thermal power stations

    NASA Astrophysics Data System (ADS)

    Trofimov, A. V.

    2009-10-01

    The structure of modern microprocessor systems for automated control of technological processes at cogeneration stations is considered. Methods for computer-aided designing of the lower (sensors and actuators) and upper (cabinets of computerized automation equipment) levels of an automated process control system are proposed. The composition of project documents, the structures of a project database and database of a computer-aided design system, and the way they interact with one another in the course of developing the project of an automated process control system are described. Elements of the interface between a design engineer and computer program are shown.

  18. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2003-10-01

    During the period July 1, 2003-September 30, 2003, Allegheny Energy Supply Co., LLC (Allegheny) proceeded with demonstration operations at the Willow Island Generating Station and improvements to the Albright Generating Station cofiring systems. The demonstration operations at Willow Island were designed to document integration of bio mass cofiring into commercial operations, including evaluating new sources of biomass supply. The Albright improvements were designed to increase the resource base for the projects, and to address issues that came up during the first year of operations. During this period, a major presentation summarizing the program was presented at the Pittsburgh Coal Conference. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations.

  19. Development of a physically-based planar inductors VHDL-AMS model for integrated power converter design

    NASA Astrophysics Data System (ADS)

    Ammouri, Aymen; Ben Salah, Walid; Khachroumi, Sofiane; Ben Salah, Tarek; Kourda, Ferid; Morel, Hervé

    2014-05-01

    Design of integrated power converters needs prototype-less approaches. Specific simulations are required for investigation and validation process. Simulation relies on active and passive device models. Models of planar devices, for instance, are still not available in power simulator tools. There is, thus, a specific limitation during the simulation process of integrated power systems. The paper focuses on the development of a physically-based planar inductor model and its validation inside a power converter during transient switching. The planar inductor model remains a complex device to model, particularly when the skin, the proximity and the parasitic capacitances effects are taken into account. Heterogeneous simulation scheme, including circuit and device models, is successfully implemented in VHDL-AMS language and simulated in Simplorer platform. The mixed simulation results has been favorably tested and compared with practical measurements. It is found that the multi-domain simulation results and measurements data are in close agreement.

  20. Issues in the design of an executive controller shell for Space Station automation

    NASA Technical Reports Server (NTRS)

    Erickson, William K.; Cheeseman, Peter C.

    1986-01-01

    A major goal of NASA's Systems Autonomy Demonstration Project is to focus research in artificial intelligence, human factors, and dynamic control systems in support of Space Station automation. Another goal is to demonstrate the use of these technologies in real space systems, for both round-based mission support and on-board operations. The design, construction, and evaluation of an intelligent autonomous system shell is recognized as an important part of the Systems Autonomy research program. His paper describes autonomous systems and executive controllers, outlines how these intelligent systems can be utilized within the Space Station, and discusses a number of key design issues that have been raised during some preliminary work to develop an autonomous executive controller shell at NASA Ames Research Center.

  1. U.S. Space Station Freedom Supplemental Reboost System (SRS) design and operational impacts

    NASA Astrophysics Data System (ADS)

    Winters, Brian A.; Winters, Donna M.

    1992-07-01

    Current designs of the U.S. Space Station Freedom Propulsion System require the capability to perform reboost, attitude control, and other orbit adjustment maneuvers as part of normal operations. In order to reduce the quantity of hydrazine consumed by the Primary Propulsion System, the propulsion system includes the capability to propulsively dispose waste gases that are generated by various station systems and experiments. The impulses generated by the Supplemental Reboost System (SRS) are used to offset orbital decay due to atmospheric drag and reduce propellant requirements. This paper presents the designs of the SRS including schematics of the waste gas collection architecture, various system and component characteristics, and methods of system operation. Estimates of waste gas quantities, propellant savings, and operational altitude impacts are provided.

  2. Proposed CTV design reference missions in support of Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Saucillo, Rudy J.; Cirillo, William M.

    1991-01-01

    Use of design reference missions (DRM's) for the cargo transfer vehicle (CTV) in support of Space Station Freedom (SSF) can provide a common baseline for the design and assessment of CTV systems and mission operations. These DRM's may also provide baseline operations scenarios for integrated CTV, Shuttle, and SSF operations. Proposed DRM's for CTV, SSF, and Shuttle operations envisioned during the early post-PMC time frame and continuing through mature, SSF evolutionary operations are described. These proposed DRM's are outlines for detailed mission definition; by treating these DRM's as top-level input for mission design studies, a range of parametric studies for systems/operations may be performed. Shuttle flight design experience, particularly rendezvous flight design, provides an excellent basis for DRM operations studies. To begin analysis of the DRM's, shuttle trajectory design tools were used in single case analysis to define CTV performance requirements. A summary of these results is presented.

  3. Proposed CTV design reference missions in support of Space Station Freedom

    NASA Astrophysics Data System (ADS)

    Saucillo, Rudy J.; Cirillo, William M.

    Use of design reference missions (DRM's) for the cargo transfer vehicle (CTV) in support of Space Station Freedom (SSF) can provide a common baseline for the design and assessment of CTV systems and mission operations. These DRM's may also provide baseline operations scenarios for integrated CTV, Shuttle, and SSF operations. Proposed DRM's for CTV, SSF, and Shuttle operations envisioned during the early post-PMC time frame and continuing through mature, SSF evolutionary operations are described. These proposed DRM's are outlines for detailed mission definition; by treating these DRM's as top-level input for mission design studies, a range of parametric studies for systems/operations may be performed. Shuttle flight design experience, particularly rendezvous flight design, provides an excellent basis for DRM operations studies. To begin analysis of the DRM's, shuttle trajectory design tools were used in single case analysis to define CTV performance requirements. A summary of these results is presented.

  4. The Space Station Freedom Flight Telerobotic Servicer: the design and evolution of a dexterous space robot

    NASA Technical Reports Server (NTRS)

    McCain, H. G.; Andary, J. F.; Hewitt, D. R.; Haley, D. C.

    1991-01-01

    The Flight Telerobotic Servicer (FTS) Project at the Goddard Space Flight Center is developing an advanced telerobotic system to assist in and reduce crew extravehicular activity (EVA) for Space Station) Freedom (SSF). The FTS will provide a telerobotic capability to the Freedom Station in the early assembly phases of the program and will be employed for assembly, maintenance, and inspection applications throughout the lifetime of the space station. Appropriately configured elements of the FTS will also be employed for robotic manipulation in remote satellite servicing applications and possibly the Lunar/Mars Program. In mid-1989, the FTS entered the flight system design and implementation phase (Phase C/D) of development with the signing of the FTS prime contract with Martin Marietta Astronautics Group in Denver, Colorado. The basic FTS design is now established and can be reported on in some detail. This paper will describe the FTS flight system design and the rationale for the specific design approaches and component selections. The current state of space technology and the nature of the FTS task dictate that the FTS be designed with sophisticated teleoperation capabilities for its initial primary operating mode. However, there are technologies, such as advanced computer vision and autonomous planning techniques currently in research and advanced development phases which would greatly enhance the FTS capabilities to perform autonomously in less structured work environments. Therefore, a specific requirement on the initial FTS design is that it has the capability to evolve as new technology becomes available. This paper will describe the FTS design approach for evolution to more autonomous capabilities. Some specific task applications of the FTS and partial automation approaches of these tasks will also be discussed in this paper.

  5. The Space Station Freedom Flight Telerobotic Servicer: the design and evolution of a dexterous space robot.

    PubMed

    McCain, H G; Andary, J F; Hewitt, D R; Haley, D C

    1991-01-01

    The Flight Telerobotic Servicer (FTS) Project at the Goddard Space Flight Center is developing an advanced telerobotic system to assist in and reduce crew extravehicular activity (EVA) for Space Station) Freedom (SSF). The FTS will provide a telerobotic capability to the Freedom Station in the early assembly phases of the program and will be employed for assembly, maintenance, and inspection applications throughout the lifetime of the space station. Appropriately configured elements of the FTS will also be employed for robotic manipulation in remote satellite servicing applications and possibly the Lunar/Mars Program. In mid-1989, the FTS entered the flight system design and implementation phase (Phase C/D) of development with the signing of the FTS prime contract with Martin Marietta Astronautics Group in Denver, Colorado. The basic FTS design is now established and can be reported on in some detail. This paper will describe the FTS flight system design and the rationale for the specific design approaches and component selections. The current state of space technology and the nature of the FTS task dictate that the FTS be designed with sophisticated teleoperation capabilities for its initial primary operating mode. However, there are technologies, such as advanced computer vision and autonomous planning techniques currently in research and advanced development phases which would greatly enhance the FTS capabilities to perform autonomously in less structured work environments. Therefore, a specific requirement on the initial FTS design is that it has the capability to evolve as new technology becomes available. This paper will describe the FTS design approach for evolution to more autonomous capabilities. Some specific task applications of the FTS and partial automation approaches of these tasks will also be discussed in this paper. PMID:11540062

  6. Design and development of a Space Station proximity operations research and development mockup

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1986-01-01

    Proximity operations (Prox-Ops) on-orbit refers to all activities taking place within one km of the Space Station. Designing a Prox-Ops control station calls for a comprehensive systems approach which takes into account structural constraints, orbital dynamics including approach/departure flight paths, myriad human factors and other topics. This paper describes a reconfigurable full-scale mock-up of a Prox-Ops station constructed at Ames incorporating an array of windows (with dynamic star field, target vehicle(s), and head-up symbology), head-down perspective display of manned and unmanned vehicles, voice- actuated 'electronic checklist', computer-generated voice system, expert system (to help diagnose subsystem malfunctions), and other displays and controls. The facility is used for demonstrations of selected Prox-Ops approach scenarios, human factors research (work-load assessment, determining external vision envelope requirements, head-down and head-up symbology design, voice synthesis and recognition research, etc.) and development of engineering design guidelines for future module interiors.

  7. Thermal Control Subsystem Design for the Avionics of a Space Station Payload

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.

    1996-01-01

    A case study of the thermal control subsystem development for a space based payload is presented from the concept stage through preliminary design. This payload, the Space Acceleration Measurement System 2 (SAMS-2), will measure the acceleration environment at select locations within the International Space Station. Its thermal control subsystem must maintain component temperatures within an acceptable range over a 10 year life span, while restricting accessible surfaces to touch temperature limits and insuring fail safe conditions in the event of loss of cooling. In addition to these primary design objectives, system level requirements and constraints are imposed on the payload, many of which are driven by multidisciplinary issues. Blending these issues into the overall system design required concurrent design sessions with the project team, iterative conceptual design layouts, thermal analysis and modeling, and hardware testing. Multiple tradeoff studies were also performed to investigate the many options which surfaced during the development cycle.

  8. Design and testing of the Space Station Freedom Propellant Tank Assembly

    NASA Technical Reports Server (NTRS)

    Dudley, D. D.; Thonet, T. A.; Goforth, A. M.

    1992-01-01

    Propellant storage and management functions for the Propulsion Module of the U.S. Space Station Freedom are provided by the Propellant Tank Assembly (PTA). The PTA consists of a surface-tension type propellant acquisition device contained within a welded titanium pressure vessel. The PTA design concept was selected with high reliability and low program risk as primary goals in order to meet stringent NASA structural, expulsion, fracture control and reliability requirements. The PTA design makes use of Shuttle Orbital Maneuvering System and Peacekeeper Propellant Storage Assembly design and analysis techniques. This paper summarizes the PTA design solution and discusses the underlying detailed analyses. In addition, design verification and qualification test activities are discussed.

  9. A novel design project for space solar power station (SSPS-OMEGA)

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Zhang, Yiqun; Duan, Baoyan; Wang, Dongxu; Li, Xun

    2016-04-01

    The space solar power station (SSPS) capable of providing earth with primary power has been researched for 50 years. The SSPS is a tremendous design involving optics, mechanics, electromagnetism, thermology, control, and other disciplines. This paper presents a novel design project for SSPS named OMEGA. The space segment of the proposed GEO-based SSPS is composed of four main parts, such as spherical solar power collector, hyperboloid photovoltaic (PV) cell array, power management and distribution (PMAD) and microwave transmitting antenna. Principle of optics, structure configuration, wired and wireless power transmissions are presented.

  10. Design of a delay-locked-loop-based time-to-digital converter

    NASA Astrophysics Data System (ADS)

    Zhaoxin, Ma; Xuefei, Bai; Lu, Huang

    2013-09-01

    A time-to-digital converter (TDC) based on a reset-free and anti-harmonic delay-locked loop (DLL) circuit for wireless positioning systems is discussed and described. The DLL that generates 32-phase clocks and a cycle period detector is employed to avoid “false locking". Driven by multiphase clocks, an encoder detects pulses and outputs the phase of the clock when the pulse arrives. The proposed TDC was implemented in SMIC 0.18 μm CMOS technology, and its core area occupies 0.7 × 0.55 mm2. The reference frequency ranges from 20 to 150 MHz. An LSB resolution of 521 ps can be achieved by using a reference clock of 60 MHz and the DNL is less than ±0.75 LSB. It dissipates 31.5 mW at 1.8 V supply voltage.