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Sample records for planck-lfi flight model

  1. Planck LFI flight model feed horns

    CERN Document Server

    Villa, F; Pecora, M; Figini, L; Nesti, R; Simonetto, A; Sozzi, C; Sandri, M; Battaglia, P; Guzzi, P; Bersanelli, M; Butler, R C; Mandolesi, N; 10.1088/1748-0221/4/12/T12004

    2010-01-01

    this paper is part of the Prelaunch status LFI papers published on JINST: http://www.iop.org/EJ/journal/-page=extra.proc5/jinst The Low Frequency Instrument is optically interfaced with the ESA Planck telescope through 11 corrugated feed horns each connected to the Radiometer Chain Assembly (RCA). This paper describes the design, the manufacturing and the testing of the flight model feed horns. They have been designed to optimize the LFI optical interfaces taking into account the tight mechanical requirements imposed by the Planck focal plane layout. All the eleven units have been successfully tested and integrated with the Ortho Mode transducers.

  2. The Planck-LFI flight model ortho-mode transducers

    Energy Technology Data Exchange (ETDEWEB)

    D' Arcangelo, O; Simonetto, A; Figini, L; Garavaglia, S; Sozzi, C [Istituto di Fisica del Plasma - CNR, via Cozzi 53, 20125 Milano (Italy); Pagana, E; Villa, F; Butler, R C; Mandolesi, N [Istituto di Astrofisica Spaziale e Fisica Cosmica, INAF, via P. Gobetti 101, 40129 Bologna (Italy); Pecora, M; Battaglia, P; Guzzi, P [Thales Alenia Space Italia, S.S. Padana Superiore 290, 20090 Vimodrone (Italy); Bersanelli, M, E-mail: ocleto@ifp.cnr.i [Universita degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy)

    2009-12-15

    The Low Frequency Instrument (LFI) of the ESA Planck CMB mission is an array of 22 ultra sensitive pseudocorrelation radiometers working at 30, 44, and 70 GHz. LFI has been calibrated and delivered for integration with the satellite to the European Space Agency on November 2006. The aim of Planck is to measure the anisotropy and polarization of the Cosmic Background Radiation with a sensitivity and angular resolution never reached before over the full sky. LFI is intrinsically sensitive to polarization thanks to the use of Ortho-Mode Transducers (OMT) located between the feedhorns and the pseudo-correlation radiometers. The OMTs are microwave passive components that divide the incoming radiation into two linear orthogonal components. A set of 11 OMTs (2 at 30 GHz, 3 at 44 GHz, and 6 at 70 GHz) were produced and tested. This work describes the design, development and performance of the eleven Flight Model OMTs of LFI. The final design was reached after several years of development. At first, Elegant Bread Board OMTs were produced to investigate the manufacturing technology and design requirements. Then, a set of 3 Qualification Model (QM) OMTs were designed, manufactured and tested in order to freeze the design and the manufacturing technology for the flight units. Finally, the Flight Models were produced and tested. It is shown that all the OMT units have been accepted for flight and the electromagnetic performance is at least marginally compliant with the requirements. Mechanically, the units passed all the thermoelastic qualification tests after a reworking necessary after the QM campaign.

  3. The linearity response of the Planck-LFI flight model receivers

    Energy Technology Data Exchange (ETDEWEB)

    Mennella, A; Bersanelli, M [Universita degli Studi di Milano, Dipartimento di Fisica, Via Celoria 16, 20133 Milano (Italy); Villa, F; Terenzi, L; Cuttaia, F; Butler, R C [INAF-IASF Bologna, Via P.Gobetti 101, 40129 Bologna (Italy); Battaglia, P; Franceschet, C; Lapolla, P M [Thales Alenia Space - Italia, S.S. Padana Superiore 290, 20090 Vimodrone, Milano (Italy); D' Arcangelo, O [CNR, Istituto di Fisica del Plasma, Via Roberto Cozzi 53, 20125 Milano (Italy); Artal, E [Departamento de Ingenieria de Comunicaciones, Universidad de Cantabria, Avenida de los Castros s/n. 39005 Santander (Spain); Davis, R; Kettle, D [Jodrell Bank Centre for Astrophysics, University of Manchester, M13 9PL (United Kingdom); Frailis, M; Galeotta, S [INAF - Osservatorio Astronomico di Trieste, Via Tiepolo 11, 34012 Trieste (Italy); Gregorio, A [Universita degli Studi di Trieste, Dipartimenti di fisica Via Valerio 2, 34127 Trieste (Italy); Hughes, N; Jukkala, P; Kilpiae, V-H [DA-Design Oj, Keskuskatu 29, FI-31600 Jokioinen (Finland); Laaninen, M, E-mail: aniello.mennella@fisica.unimi.i [Ylinen Electronics Oy, Teollisuustie 9A, FIN-02700 Kauniainen (Finland)

    2009-12-15

    In this paper we discuss the linearity response of the Planck-LFI receivers, with particular reference to signal compression measured on the 30 and 44 GHz channels. In the article we discuss the various sources of compression and present a model that accurately describes data measured during tests performed with individual radiomeric chains. After discussing test results we present the best parameter set representing the receiver response and discuss the impact of non linearity on in-flight calibration, which is shown to be negligible.

  4. The PLANCK LFI flight model ortho-mode transducers

    CERN Document Server

    D'Arcangelo, O; Figini, L; Pagana, E; Villa, F; Pecora, M; Battaglia, P; Bersanelli, M; Butler, R C; Garavaglia, S; Guzzi, P; Mandolesi, N; Sozzi, C; 10.1088/1748-0221/4/12/T12005

    2009-01-01

    The Low Frequency Instrument (LFI) of the ESA Planck CMB mission is an array of 22 ultra sensitive pseudocorrelation radiometers working at 30, 44, and 70 GHz. LFI has been calibrated and delivered for integration with the satellite to the European Space Agency on November 2006. The aim of Planck is to measure the anisotropy and polarization of the Cosmic Background Radiation with a sensitivity and angular resolution never reached before over the full sky. LFI is intrinsically sensitive to polarization thanks to the use of Ortho-Mode Transducers (OMT) located between the feedhorns and the pseudo-correlation radiometers. The OMTs are microwave passive components that divide the incoming radiation into two linear orthogonal components. A set of 11 OMTs (2 at 30 GHz, 3 at 44 GHz, and 6 at 70 GHz) were produced and tested. This work describes the design, development and performance of the eleven Flight Model OMTs of LFI. The final design was reached after several years of development. At first, Elegant Bread Boar...

  5. Dynamic validation of the Planck/LFI thermal model

    CERN Document Server

    Tomasi, M; Gregorio, A; Colombo, F; Lapolla, M; Terenzi, L; Morgante, G; Bersanelli, M; Butler, R C; Galeotta, S; Mandolesi, N; Maris, M; Mennella, A; Valenziano, L; Zacchei, A; 10.1088/1748-0221/5/01/T01002

    2010-01-01

    The Low Frequency Instrument (LFI) is an array of cryogenically cooled radiometers on board the Planck satellite, designed to measure the temperature and polarization anisotropies of the cosmic microwave backgrond (CMB) at 30, 44 and 70 GHz. The thermal requirements of the LFI, and in particular the stringent limits to acceptable thermal fluctuations in the 20 K focal plane, are a critical element to achieve the instrument scientific performance. Thermal tests were carried out as part of the on-ground calibration campaign at various stages of instrument integration. In this paper we describe the results and analysis of the tests on the LFI flight model (FM) performed at Thales Laboratories in Milan (Italy) during 2006, with the purpose of experimentally sampling the thermal transfer functions and consequently validating the numerical thermal model describing the dynamic response of the LFI focal plane. This model has been used extensively to assess the ability of LFI to achieve its scientific goals: its valid...

  6. Dynamic validation of the Planck-LFI thermal model

    Energy Technology Data Exchange (ETDEWEB)

    Tomasi, M; Bersanelli, M; Mennella, A [Universita degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); Cappellini, B [INAF IASF Milano, Via Bassini, 15, 20133, Milano (Italy); Gregorio, A [University of Trieste, Department of Physics, via Valerio 2, 34127 Trieste (Italy); Colombo, F; Lapolla, M [Thales Alenia Space Italia S.p.A., IUEL - Scientific Instruments, S.S. Padana Superiore 290, 20090 Vimodrone (Mi) (Italy); Terenzi, L; Morgante, G; Butler, R C; Mandolesi, N; Valenziano, L [INAF IASF Bologna, via Gobetti 101, 40129 Bologna (Italy); Galeotta, S; Maris, M; Zacchei, A [LFI-DPC INAF-OATs, via Tiepolo 11, 34131 Trieste (Italy)

    2010-01-15

    The Low Frequency Instrument (LFI) is an array of cryogenically cooled radiometers on board the Planck satellite, designed to measure the temperature and polarization anisotropies of the cosmic microwave background (CMB) at 30, 44 and 70 GHz. The thermal requirements of the LFI, and in particular the stringent limits to acceptable thermal fluctuations in the 20 K focal plane, are a critical element to achieve the instrument scientific performance. Thermal tests were carried out as part of the on-ground calibration campaign at various stages of instrument integration. In this paper we describe the results and analysis of the tests on the LFI flight model (FM) performed at Thales Laboratories in Milan (Italy) during 2006, with the purpose of experimentally sampling the thermal transfer functions and consequently validating the numerical thermal model describing the dynamic response of the LFI focal plane. This model has been used extensively to assess the ability of LFI to achieve its scientific goals: its validation is therefore extremely important in the context of the Planck mission. Our analysis shows that the measured thermal properties of the instrument show a thermal damping level better than predicted, therefore further reducing the expected systematic effect induced in the LFI maps. We then propose an explanation of the increased damping in terms of non-ideal thermal contacts.

  7. Advanced modelling of the Planck-LFI radiometers

    Energy Technology Data Exchange (ETDEWEB)

    Battaglia, P [Thales Alenia Space Italia S.p.A., S.S. Padana Superiore 290, 20090 Vimodrone (Italy); Franceschet, C; Bersanelli, M; Maino, D; Mennella, A [Universita di Milano, Dipartimento di Fisica, Via G. Celoria 16, I-20133 Milano (Italy); Zonca, A [INAF-IASF Milano, Via E. Bassini 15, I-20133 Milano (Italy); Butler, R C; Mandolesi, N [INAF-IASF Bologna, Via P. Gobetti, 101, I-40129 Bologna (Italy); D' Arcangelo, O; Platania, P [IFP-CNR, via Cozzi 53, 20125 Milano (Italy); Davis, R J [Jodrell Bank Centre for Astrophysics, Alan Turing Building, The University of Manchester, Manchester, M13 9PL (United Kingdom); Galeotta, S [INAF-OATs, Via G.B. Tiepolo 11, I-34131, Trieste (Italy); Guzzi, P [Numonyx, R and D Technology Center, Via C. Olivetti 2, 20041 Agrate Brianza (Italy); Hoyland, R [Instituto de AstrofIsica de Canarias, C/ Via Lactea S/N, E-38200, La Laguna (Tenerife) (Spain); Hughes, N; Jukkala, P [DA-Design Oy Jokioinen (Finland); Kettle, D [School of Electrical and Electronic Engineering, University of Manchester, Manchester, M60 1QD (United Kingdom); Laaninen, M [Ylinen Electronics Oy Kauniainen (Finland); Leonardi, R; Meinhold, P, E-mail: paola.battaglia@thalesaleniaspace.co [Department of Physics, University of California, Santa Barbara, CA 93106-9530 (United States)

    2009-12-15

    The Low Frequency Instrument (LFI) is a radiometer array covering the 30-70 GHz spectral range on-board the ESA Planck satellite, launched on May 14th, 2009 to observe the cosmic microwave background (CMB) with unprecedented precision. In this paper we describe the development and validation of a software model of the LFI pseudo-correlation receivers which enables to reproduce and predict all the main system parameters of interest as measured at each of the 44 LFI detectors. These include system total gain, noise temperature, band-pass response, non-linear response. The LFI Advanced RF Model (LARFM) has been constructed by using commercial software tools and data of each radiometer component as measured at single unit level. The LARFM has been successfully used to reproduce the LFI behavior observed during the LFI ground-test campaign. The model is an essential element in the database of LFI data processing center and will be available for any detailed study of radiometer behaviour during the survey.

  8. The Planck-LFI flight model composite waveguides

    CERN Document Server

    D'Arcangelo, O; Simonetto, A; Villa, F; Pecora, M; Battaglia, P; Bersanelli, M; Butler, R C; Cuttaia, F; Garavaglia, S; Guzzi, P; Mandolesi, N; Mennella, A; Morgante, G; Pagan, L; Valenziano, L; 10.1088/1748-0221/4/12/T12007

    2009-01-01

    The Low Frequency Instrument on board the PLANCK satellite is designed to give the most accurate map ever of the CMB anisotropy of the whole sky over a broad frequency band spanning 27 to 77 GHz. It is made of an array of 22 pseudo-correlation radiometers, composed of 11 actively cooled (20 K) Front End Modules (FEMs), and 11 Back End Modules (BEMs) at 300K. The connection between the two parts is made with rectangular Wave Guides. Considerations of different nature (thermal, electromagnetic and mechanical), imposed stringent requirements on the WGs characteristics and drove their design. From the thermal point of view, the WG should guarantee good insulation between the FEM and the BEM sections to avoid overloading the cryocooler. On the other hand it is essential that the signals do not undergo excessive attenuation through the WG. Finally, given the different positions of the FEM modules behind the focal surface and the mechanical constraints given by the surrounding structures, different mechanical design...

  9. Critical Design Decisions of The Planck LFI Level 1 Software

    Science.gov (United States)

    Morisset, N.; Rohlfs, R.; Türler, M.; Meharga, M.; Binko, P.; Beck, M.; Frailis, M.; Zacchei, A.

    2010-12-01

    The PLANCK satellite with two on-board instruments, a Low Frequency Instrument (LFI) and a High Frequency Instrument (HFI) has been launched on May 14th with Ariane 5. The ISDC Data Centre for Astrophysics in Versoix, Switzerland has developed and maintains the Planck LFI Level 1 software for the Data Processing Centre (DPC) in Trieste, Italy. The main tasks of the Level 1 processing are to retrieve the daily available scientific and housekeeping (HK) data of the LFI instrument, the Sorption Cooler and the 4k Cooler data from Mission Operation Centre (MOC) in Darmstadt; to sort them by time and by type (detector, observing mode, etc...); to extract the spacecraft attitude information from auxiliary files; to flag the data according to several criteria; and to archive the resulting Time Ordered Information (TOI), which will then be used to produce maps of the sky in different spectral bands. The output of the Level 1 software are the TOI files in FITS format, later ingested into the Data Management Component (DMC) database. This software has been used during different phases of the LFI instrument development. We started to reuse some ISDC components for the LFI Qualification Model (QM) and we completely rework the software for the Flight Model (FM). This was motivated by critical design decisions taken jointly with the DPC. The main questions were: a) the choice of the data format: FITS or DMC? b) the design of the pipelines: use of the Planck Process Coordinator (ProC) or a simple Perl script? c) do we adapt the existing QM software or do we restart from scratch? The timeline and available manpower are also important issues to be taken into account. We present here the orientation of our choices and discuss their pertinence based on the experience of the final pre-launch tests and the start of real Planck LFI operations.

  10. Planck-LFI radiometers tuning

    Energy Technology Data Exchange (ETDEWEB)

    Cuttaia, F; Stringhetti, L; Terenzi, L; Villa, F; Butler, R C; Franceschi, E [Istituto di Astrofisica Spaziale e Fisica Cosmica, INAF, via P. Gobetti 101, 40129 Bologna (Italy); Mennella, A; Tomasi, M; Bersanelli, M; Cappellini, B; Franceschet, C; Hoyland, R [Universita degli Studi di Milano, via Celoria 16, 20133 Milano (Italy); Maris, M; Frailis, M [INAF / OATS, via Tiepolo 11, 34143 Trieste (Italy); Cuevas, L P [Research and Scientific Support Department of ESA, ESTEC, Noordwijk (Netherlands); D' Arcangelo, O [IFP-CNR, via Cozzi 53, 20013 Milano (Italy); Davis, R; Lowe, S [Jodrell Bank Centre for Astrophysics, Alan Turing Building, The University of Manchester, Manchester, M13 9PL (United Kingdom); Gregorio, A [University of Trieste, Department of Physics, via Valerio 2, 34127 Trieste (Italy); Leonardi, R, E-mail: cuttaia@iasfbo.inaf.i [Department of Physics, University of California, Santa Barbara, CA 93106-9530 (United States)

    2009-12-15

    This paper describes the Planck Low Frequency Instrument tuning activities performed through the ground test campaigns, from Unit to Satellite Levels. Tuning is key to achieve the best possible instrument performance and tuning parameters strongly depend on thermal and electrical conditions. For this reason tuning has been repeated several times during ground tests and it has been repeated in flight before starting nominal operations. The paper discusses the tuning philosophy, the activities and the obtained results, highlighting developments and changes occurred during test campaigns. The paper concludes with an overview of tuning performed during the satellite cryogenic test campaign (Summer 2008) and of the plans for the just started in-flight calibration.

  11. PLANCK LFI Level 1 Processing During Operations

    Science.gov (United States)

    Morisset, N.; Rohlfs, R.; Türler, M.; Meharga, M.; Binko, P.; Beck, M.; Frailis, M.; Zacchei, A.; Galeotta, S.

    2008-08-01

    The PLANCK satellite with two on-board instruments, a Low Frequency Instrument (LFI) and a High Frequency Instrument (HFI) is foreseen to be launched in August 2008 with Ariane 5. The Data Processing Centre (DPC) in Trieste, Italy for LFI is responsible for processing the PLANCK LFI data. The ISDC data centre in Switzerland is responsible for developing/installing and maintaining the software for the LFI Level 1 data processing presented here. The main tasks of the Level 1 processing are to retrieve the daily available consolidated scientific and housekeeping (HK) data of the LFI instrument from the Mission Operation Centre in Darmstadt (MOC); to sort them by time and by type (detector, observing mode, etc...); to extract the spacecraft attitude information from auxiliary files; to flag the data according to several criteria; and to archive the resulting Time Ordered Information (TOI). The TOI data generated by the level 1 pipeline are the input for the more scientific LFI level 2 processing. The TOI are first stored in FITS format and then ingested into the Data Management Component (DMC) system, which is the interface to the LFI DPC database. In addition, the ISDC also developed software tools to display and perform a quick look analysis of the data.

  12. The Planck-LFI Radiometer Electronics Box Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Herreros, J M; Gomez, M F; Rebolo, R; Chulani, H; Rubino-Martin, J A; Hildebrandt, S R [Instituto de Astrofisica de Canarias (IAC), 38200 La Laguna, Tenerife (Spain); Bersanelli, M; Franceschet, C [Universita di Milano, Dipartamento di Fisica, Via G. Celoria 16, 20133 Milano (Italy); Butler, R C [INAF-IASF Bologna, Via P. Gobetti 101, 40129 Bologna (Italy); Miccolis, M [Thales Alenia Space Italia S.p.A., IUEL - Scientific Instruments, S.S. Padana Superiore 290, 20090 Vimodrone (Italy); Pena, A; Pereira, M; Torrero, F; Lopez, M; Alcala, C, E-mail: rrl@iac.e [EADS Astrium CRISA, C/Torres Quevedo, 9, 28760 Tres Cantos (Spain)

    2009-12-15

    The Radiometer Electronics Box Assembly (REBA) is the control and data processing on board computer of the Low Frequency Instrument (LFI) of the Planck mission (ESA). The REBA was designed and built incorporating state of the art processors, communication interfaces and real time operating system software in order to meet the scientific performance of the LFI. We present a technical summary of the REBA, including a physical, functional, electrical, mechanical and thermal description. Aspects of the design and development, the assembly, the integration and the verification of the equipment are provided. A brief description of the LFI on board software is given including the Low-Level Software and the main functionalities and architecture of the Application Software. The compressor module, which has been developed as an independent product, later integrated in the application, is also described in this paper. Two identical engineering models EM and AVM, the engineering qualification model EQM, the flight model FM and flight spare have been manufactured and tested. Low-level and Application software have been developed. Verification activities demonstrated that the REBA hardware and software fulfil all the specifications and perform as required for flight operation.

  13. The Planck/LFI Radiometer Electronics Box Assembly

    CERN Document Server

    Herreros, J M; Rebolo, R; Chulani, H; Rubino-Martin, J A; Hildebrandt, S R; Bersanelli, M; Butler, R C; Miccolis, M; Pena, A; Pereira, M; Torrero, F; Franceschet, C; Lopez, M; Alcala, C; 10.1088/1748-0221/4/12/T12008

    2010-01-01

    The Radiometer Electronics Box Assembly (REBA) is the control and data processing on board computer of the Low Frequency Instrument (LFI) of the Planck mission (ESA). The REBA was designed and built incorporating state of the art processors, communication interfaces and real time operating system software in order to meet the scientific performance of the LFI. We present a technical summary of the REBA, including a physical, functional, electrical, mechanical and thermal description. Aspects of the design and development, the assembly, the integration and the verification of the equipment are provided. A brief description of the LFI on board software is given including the Low-Level Software and the main functionalities and architecture of the Application Software. The compressor module, which has been developed as an independent product, later integrated in the application, is also described in this paper. Two identical engineering models EM and AVM, the engineering qualification model EQM, the flight model ...

  14. Off-line radiometric analysis of Planck-LFI data

    Energy Technology Data Exchange (ETDEWEB)

    Tomasi, M; Mennella, A; Bersanelli, M [Dipartimento di Fisica, Universita degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); Galeotta, S; Maris, M [LFI-DPC INAF-OATs, Via Tiepolo 11, 34131 Trieste (Italy); Lowe, S R [Jodrell Bank Centre for Astrophysics, The University of Manchester, Manchester, M13 9PL (United Kingdom); Mendes, L [Planck Science Office, European Space Agency, ESAC, P.O. box 78, 28691 Villanueva de la Canada, Madrid (Spain); Leonardi, R; Meinhold, P [Department of Physics, University of California, Santa Barbara, CA 93106-9530 (United States); Villa, F; Sandri, M; Cuttaia, F; Terenzi, L; Valenziano, L; Butler, R C [INAF-IASF Bologna, Via Gobetti, 101, 40129, Bologna (Italy); Cappellini, B [INAF-IASF Milano, Via E. Bassini 15, 20133 Milano (Italy); Gregorio, A [Department of Physics, University of Trieste, Via Valerio, 2 Trieste I-34127 (Italy); Salmon, M J [Departamento de IngenierIa de Comunicaciones, Universidad de Cantabria, Avenida de los Castros s/n. 39005 Santander (Spain); Binko, P [ISDC Data Centre for Astrophysics, University of Geneva, ch. d' Ecogia 16, 1290 Versoix (Switzerland); D' Arcangelo, O, E-mail: tomasi@lambrate.inaf.i [IFP-CNR, Via Cozzi 53, Milano (Italy)

    2009-12-15

    The Planck Low Frequency Instrument (LFI) is an array of 22 pseudo-correlation radiometers on-board the Planck satellite to measure temperature and polarization anisotropies in the Cosmic Microwave Background (CMB) in three frequency bands (30, 44 and 70 GHz). To calibrate and verify the performances of the LFI, a software suite named LIFE has been developed. Its aims are to provide a common platform to use for analyzing the results of the tests performed on the single components of the instrument (RCAs, Radiometric Chain Assemblies) and on the integrated Radiometric Array Assembly (RAA). Moreover, its analysis tools are designed to be used during the flight as well to produce periodic reports on the status of the instrument. The LIFE suite has been developed using a multi-layered, cross-platform approach. It implements a number of analysis modules written in RSI IDL, each accessing the data through a portable and heavily optimized library of functions written in C and C++. One of the most important features of LIFE is its ability to run the same data analysis codes both using ground test data and real flight data as input. The LIFE software suite has been successfully used during the RCA/RAA tests and the Planck Integrated System Tests. Moreover, the software has also passed the verification for its in-flight use during the System Operations Verification Tests, held in October 2008.

  15. Noise properties of the Planck-LFI receivers

    Energy Technology Data Exchange (ETDEWEB)

    Meinhold, P; Leonardi, R [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Aja, B; Artal, E; Fuente, M L de la [Departamento de Ingenieria de Comunicaciones, Universidad de Cantabria, Avenida Los Castros s/n. 39005, Santander (Spain); Battaglia, P; Franceschet, C [Thales Alenia Space Italia S.p.A., IUEL - Scientific Instruments, S.S. Padana Superiore 290, 20090 Vimodrone Milano (Italy); Bersanelli, M [Universita degli Studi di Milano, Dipartamento di Fisica, via Celoria 16, 20133, Milano (Italy); Blackhurst, E; Davis, R [Jodrell Bank Centre for Astrophysics, Alan Turing Building, The University of Manchester, Manchester, M13 9PL (United Kingdom); Butler, C R; Cuttaia, F; Franceschi, E [INAF/IASF, via P. Gobetti 101, 40129 Bologna (Italy); Cuevas, L P [ESTEC, Keplerlaan 1, Postbus 299 2200 AG Noordwijk (Netherlands); D' Arcangelo, O [Istituto di Fisica del Plasma CNR, via Cozzi 53, 20125 Milan (Italy); Frailis, M; Galeotta, S [INAF/OATs, via Tiepolo, 11, 34143 Trieste (Italy); Gaier, T [Jet Propulsion Laboratory, Pasadena, CA 91109 (United States); Gregorio, A [University of Trieste, Department of Physics, via Valerio 2, 34127 Trieste (Italy); Hoyland, R, E-mail: peterm@cfi.ucsb.ed [Instituto de AstrofIsica de Canarias, C/ VIa Lactea S/N, E-38200, La Laguna, Tenerife (Spain)

    2009-12-15

    The Planck Low Frequency Instrument (LFI) radiometers have been tested extensively during several dedicated campaigns. The present paper reports the principal noise properties of the LFI radiometers. A brief description of the LFI radiometers is given along with details of the test campaigns relevant to determination of noise properties. Current estimates of flight sensitivities, 1/f parameters, and noise effective bandwidths are presented. The LFI receivers exhibit exceptional 1/f noise, and their white noise performance is sufficient for the science goals of Planck.

  16. Off-line radiometric analysis of Planck/LFI data

    CERN Document Server

    Tomasi, M; Galeotta, S; Lowe, S R; Mendes, L; Leonardi, R; Villa, F; Cappellini, B; Gregorio, A; Meinhold, P; Sandri, M; Cuttaia, F; Terenzi, L; Maris, M; Valenziano, L; Salmon, M J; Bersanelli, M; Binko, P; Butler, R C; D'Arcangelo, O; Fogliani, S; Frailis, M; Franceschi, E; Gasparo, F; Maggio, G; Maino, D; Malaspina, M; Mandolesi, N; Manzato, P; Meharga, M; Morgante, G; Morisset, N; Pasian, F; Perrotta, F; Rohlfs, R; Turler, M; Zacchei, A; Zonca, A; 10.1088/1748-0221/4/12/T12020

    2009-01-01

    The Planck Low Frequency Instrument (LFI) is an array of 22 pseudo-correlation radiometers on-board the Planck satellite to measure temperature and polarization anisotropies in the Cosmic Microwave Background (CMB) in three frequency bands (30, 44 and 70 GHz). To calibrate and verify the performances of the LFI, a software suite named LIFE has been developed. Its aims are to provide a common platform to use for analyzing the results of the tests performed on the single components of the instrument (RCAs, Radiometric Chain Assemblies) and on the integrated Radiometric Array Assembly (RAA). Moreover, its analysis tools are designed to be used during the flight as well to produce periodic reports on the status of the instrument. The LIFE suite has been developed using a multi-layered, cross-platform approach. It implements a number of analysis modules written in RSI IDL, each accessing the data through a portable and heavily optimized library of functions written in C and C++. One of the most important features ...

  17. Thermal susceptibility of the Planck-LFI receivers

    Energy Technology Data Exchange (ETDEWEB)

    Terenzi, L; Morgante, G; Butler, R C; Cuttaia, F [INAF - IASF Bologna, via P. Gobetti 101, 40129 Bologna (Italy); Colin, A [Instituto de Fisica de Cantabria (CSIC-UC), Av. Los Castros s/n. 39005 Santander (Spain); Mennella, A; Tomasi, M; Bersanelli, M [Universita degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); Battaglia, P; Lapolla, M; Franceschet, C [Thales Alenia Space Italia, Sede di Milano, S.S. Padana Superiore 290, 20090, Vimodrone (Italy); D' Arcangelo, O [Istituto di Fisica del Plasma CNR, via Cozzi 53, 20125 Milan (Italy); Davis, R [Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, Manchester, M13 9PL (United Kingdom); Galeotta, S [INAF Osservatorio Astronomico di Trieste, via Tiepolo 11, Trieste 34143 (Italy); Gregorio, A [University of Trieste, Department of Physics, via Valerio 2, Trieste 34127 (Italy); Hughes, N; Jukkala, P [DA-Design Oy, Keskuskatu 29, FI-31600, Jokioinen (Finland); Kettle, D [School of Electrical and Electronic Engineering, University of Manchester, Manchester, M60 1QD (United Kingdom); Laaninen, M [Ylinen Electronics Oy, Teollisuustie 9A, FIN-02700 Kauniainen (Finland); Salmon, M J, E-mail: terenzi@iasfbo.inaf.i

    2009-12-15

    This paper describes the impact of the Planck Low Frequency Instrument front end physical temperature fluctuations on the output signal. The origin of thermal instabilities in the instrument are discussed, and an analytical model of their propagation and impact on the receivers signal is described. The experimental test setup dedicated to evaluate these effects during the instrument ground calibration is reported together with data analysis methods. Finally, main results obtained are discussed and compared to the requirements.

  18. Planck-LFI radiometers' spectral response

    Energy Technology Data Exchange (ETDEWEB)

    Zonca, A [INAF-IASF Milano, Via E. Bassini 15, 20133 Milano (Italy); Franceschet, C; Mennella, A; Bersanelli, M [Universita di Milano, Dipartimento di Fisica, Via G. Celoria 16, 20133 Milano (Italy); Battaglia, P; Silvestri, R [Thales Alenia Space Italia S.p.A., S.S. Padana Superiore 290, 20090 Vimodrone, Milano (Italy); Villa, F; Butler, R C; Cuttaia, F; Mandolesi, N [INAF-IASF Bologna, Via P. Gobetti 101, 40129 Bologna (Italy); D' Arcangelo, O [IFP-CNR, via Cozzi 53, 20125 Milano (Italy); Artal, E [Departamento de IngenierIa de Comunicaciones, Universidad de Cantabria, Avenida de los Castros s/n. 39005 Santander (Spain); Davis, R J [Jodrell Bank Centre for Astrophysics, Alan Turing Building, The University of Manchester, Manchester, M13 9PL (United Kingdom); Galeotta, S; Maris, M [INAF-OATs, Via G.B. Tiepolo 11, I-34131, Trieste (Italy); Hughes, N; Jukkala, P; Kilpiae, V-H [DA-Design Oy, Keskuskatu 29, FI-31600, Jokioinen (Finland); Laaninen, M [Ylinen Electronics Oy, Teollisuustie 9A, FIN-02700, Kauniainen (Finland); Mendes, L, E-mail: andrea.zonca@fisica.unimi.i [ESA - ESAC, Camino bajo del Castillo, s/n, Villanueva de la Canada 28692 Madrid (Spain)

    2009-12-15

    The Low Frequency Instrument (LFI) is an array of pseudo-correlation radiometers on board the Planck satellite, the ESA mission dedicated to precision measurements of the Cosmic Microwave Background. The LFI covers three bands centred at 30, 44 and 70 GHz, with a goal bandwidth of 20% of the central frequency. The characterization of the broadband frequency response of each radiometer is necessary to understand and correct for systematic effects, particularly those related to foreground residuals and polarization measurements. In this paper we present the measured band shape of all the LFI channels and discuss the methods adopted for their estimation. The spectral characterization of each radiometer was obtained by combining the measured spectral response of individual units through a dedicated RF model of the LFI receiver scheme. As a consistency check, we also attempted end-to-end spectral measurements of the integrated radiometer chain in a cryogenic chamber. However, due to systematic effects in the measurement setup, only qualitative results were obtained from these tests. The measured LFI bandpasses exhibit a moderate level of ripple, compatible with the instrument scientific requirements.

  19. Level 1 on-ground telemetry handling in Planck-LFI

    Science.gov (United States)

    Zacchei, A.; Frailis, M.; Maris, M.; Morisset, N.; Rohlfs, R.; Meharga, M.; Binko, P.; Türler, M.; Galeotta, S.; Gasparo, F.; Franceschi, E.; Butler, R. C.; Cuttaia, F.; D'Arcangelo, O.; Fogliani, S.; Gregorio, A.; Leonardi, R.; Lowe, S. R.; Maino, D.; Maggio, G.; Malaspina, M.; Mandolesi, N.; Manzato, P.; Meinhold, P.; Mendes, L.; Mennella, A.; Morgante, G.; Pasian, F.; Perrotta, F.; Sandri, M.; Stringhetti, L.; Terenzi, L.; Tomasi, M.; Zonca, A.

    2009-12-01

    The Planck Low Frequency Instrument (LFI) will observe the Cosmic Microwave Background (CMB) by covering the frequency range 30-70 GHz in three bands. The primary instrument data source are the temperature samples acquired by the 22 radiometers mounted on the Planck focal plane. Such samples represent the scientific data of LFI. In addition, the LFI instrument generates the so called housekeeping data by sampling regularly the on-board sensors and registers. The housekeeping data provides information on the overall health status of the instrument and on the scientific data quality. The scientific and housekeeping data are collected on-board into telemetry packets compliant with the ESA Packet Telemetry standards. They represent the primary input to the first processing level of the LFI Data Processing Centre. In this work we show the software systems which build the LFI Level 1. A real-time assessment system, based on the ESA SCOS 2000 generic mission control system, has the main purpose of monitoring the housekeeping parameters of LFI and detect possible anomalies. A telemetry handler system processes the housekeeping and scientific telemetry of LFI, generating timelines for each acquisition chain and each housekeeping parameter. Such timelines represent the main input to the subsequent processing levels of the LFI DPC. A telemetry quick-look system allows the real-time visualization of the LFI scientific and housekeeping data, by also calculating quick statistical functions and fast Fourier transforms. The LFI Level 1 has been designed to support all the mission phases, from the instrument ground tests and calibration to the flight operations, and developed according to the ESA engineering standards.

  20. Level 1 on-ground telemetry handling in Planck LFI

    CERN Document Server

    Zacchei, A; Maris, M; Morisset, N; Rohlfs, R; Meharga, M; Binko, P; Turler, M; Galeotta, S; Gasparo, F; Franceschi, E; Butler, R C; Cuttaia, F; D'Arcangelo, O; Fogliani, S; Gregorio, A; Leonardi, R; Lowe, S R; Maino, D; Maggio, G; Malaspina, M; Mandolesi, N; Manzato, P; Meinhold, P; Mendes, L; Mennella, A; Morgante, G; Pasian, F; Perrotta, F; Sandri, M; Stringhetti, L; Terenzi, L; Tomasi, M; Zonca, A; 10.1088/1748-0221/4/12/T12019

    2009-01-01

    The Planck Low Frequency Instrument (LFI) will observe the Cosmic Microwave Background (CMB) by covering the frequency range 30-70 GHz in three bands. The primary instrument data source are the temperature samples acquired by the 22 radiometers mounted on the Planck focal plane. Such samples represent the scientific data of LFI. In addition, the LFI instrument generates the so called housekeeping data by sampling regularly the on-board sensors and registers. The housekeeping data provides information on the overall health status of the instrument and on the scientific data quality. The scientific and housekeeping data are collected on-board into telemetry packets compliant with the ESA Packet Telemetry standards. They represent the primary input to the first processing level of the LFI Data Processing Centre. In this work we show the software systems which build the LFI Level 1. A real-time assessment system, based on the ESA SCOS 2000 generic mission control system, has the main purpose of monitoring the hou...

  1. Space Flight Cable Model Development

    Science.gov (United States)

    Spak, Kaitlin

    2013-01-01

    This work concentrates the modeling efforts presented in last year's VSGC conference paper, "Model Development for Cable-Harnessed Beams." The focus is narrowed to modeling of space-flight cables only, as a reliable damped cable model is not yet readily available and is necessary to continue modeling cable-harnessed space structures. New experimental data is presented, eliminating the low-frequency noise that plagued the first year's efforts. The distributed transfer function method is applied to a single section of space flight cable for Euler-Bernoulli and shear beams. The work presented here will be developed into a damped cable model that can be incorporated into an interconnected beam-cable system. The overall goal of this work is to accurately predict natural frequencies and modal damping ratios for cabled space structures.

  2. Efficient Global Aerodynamic Modeling from Flight Data

    Science.gov (United States)

    Morelli, Eugene A.

    2012-01-01

    A method for identifying global aerodynamic models from flight data in an efficient manner is explained and demonstrated. A novel experiment design technique was used to obtain dynamic flight data over a range of flight conditions with a single flight maneuver. Multivariate polynomials and polynomial splines were used with orthogonalization techniques and statistical modeling metrics to synthesize global nonlinear aerodynamic models directly and completely from flight data alone. Simulation data and flight data from a subscale twin-engine jet transport aircraft were used to demonstrate the techniques. Results showed that global multivariate nonlinear aerodynamic dependencies could be accurately identified using flight data from a single maneuver. Flight-derived global aerodynamic model structures, model parameter estimates, and associated uncertainties were provided for all six nondimensional force and moment coefficients for the test aircraft. These models were combined with a propulsion model identified from engine ground test data to produce a high-fidelity nonlinear flight simulation very efficiently. Prediction testing using a multi-axis maneuver showed that the identified global model accurately predicted aircraft responses.

  3. Making Maps from Planck LFI 30GHz Data with Asymmetric Beams and Cooler Noise

    Energy Technology Data Exchange (ETDEWEB)

    The Planck CTP Working Group; Ashdown, M.A.J.; Baccigalupi, C.; Bartlett, J.G.; Borrill, J.; Cantalupo, C.; de Gasperis, G.; Gorski, K.M.; Hivon, E.; Huffenberger, K.; Keihanen, E.; Keskitalo, R.; Kisner, T.; Hurki-Suonio, H.; Lawrence, C.R.; Natoli, P.; Poutanen, T.; Prezeau, G.; Reinecke, M.; Rocha, G.; Sandri, M.; Stompor, R..; Villa, F.; Wandelt, B.; de Troia, G.

    2008-06-19

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. Temperature and polarization frequency maps made from these observations are prime deliverables of the Planck mission. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. They simulated one year long observations of four 30 GHz detectors. The simulated timestreams contained CMB, foreground component (both galactic and extra-galactic), instrument nolise (correlated and white), and the four instrument systematic effects. They made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. They also compared the maps of different mapmaking codes to see how they performed. They used five mapmaking codes (two destripers and three optimal codes). None of their mapmaking codes makes an attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. This is a complicated smoothing, because every map pixel has its own effective beam. Temperature to polarization cross-coupling due to beam mismatch causes a detectable bias in the TE spectrum of the CMB map. The effects of cooler noise and pointing errors did not appear to be major concerns for the 30 GHz channel. The only essential difference found so far between mapmaking codes that affects accuracy (in terms of residual RMS) is baseline length. All optimal codes give essentially indistiguishable results. A destriper gives the same result as the optimal codes when the baseline is set short enough (Madam). For longer baselines destripers (Springtide and Madam) require less computing resources but deliver a noisier map.

  4. Making Maps from Planck LFI 30GHz Data with Asymmetric Beams and Cooler Noise

    CERN Document Server

    Ashdown, M A J; Bartlett, J G; Borrill, J; Cantalupo, C; De Gasperis, G; de Troia, G; Górski, K M; Hivon, E; Huffenberger, Kevin M; Keihanen, E; Keskitalo, R; Kisner, T; Kurki-Suonio, H; Lawrence, C R; Natoli, P; Poutanen, T; Prezeau, G; Reinecke, M; Rocha, G; Sandri, M; Stompor, R; Villa, F; Wandelt, B

    2008-01-01

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. We simulated one year long observations of four 30 GHz detectors. The simulated timestreams contained CMB, foreground components (both galactic and extra-galactic), instrument noise (correlated and white), and the four instrument systematic effects. We made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. We also compared the maps of different mapmaking codes to see how they performed. We used five mapmaking codes (two destripers and three optimal codes). None of our mapmaking codes makes an attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. Temperature to pol...

  5. Making maps from Planck LFI 30 GHz data with asymmetric beams and cooler noise

    Science.gov (United States)

    Ashdown, M. A. J.; Baccigalupi, C.; Bartlett, J. G.; Borrill, J.; Cantalupo, C.; de Gasperis, G.; de Troia, G.; Górski, K. M.; Hivon, E.; Huffenberger, K.; Keihänen, E.; Keskitalo, R.; Kisner, T.; Kurki-Suonio, H.; Lawrence, C. R.; Natoli, P.; Poutanen, T.; Prézeau, G.; Reinecke, M.; Rocha, G.; Sandri, M.; Stompor, R.; Villa, F.; Wandelt, B.; Planck Ctp Working Group

    2009-01-01

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. Temperature and polarization frequency maps made from these observations are prime deliverables of the Planck mission. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. We simulated one-year long observations of four 30 GHz detectors. The simulated timestreams contained cosmic microwave background (CMB) signal, foreground components (both galactic and extra-galactic), instrument noise (correlated and white), and the four instrument systematic effects. We made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. We also compared the maps of different mapmaking codes to see how they performed. We used five mapmaking codes (two destripers and three optimal codes). None of our mapmaking codes makes any attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. This is a complicated smoothing, because each map pixel has its own effective beam. Temperature to polarization cross-coupling due to beam mismatch causes a detectable bias in the TE spectrum of the CMB map. The effects of cooler noise and pointing errors did not appear to be major concerns for the 30 GHz channel. The only essential difference found so far between mapmaking codes that affects accuracy (in terms of residual root-mean-square) is baseline length. All optimal codes give essentially indistinguishable results. A destriper gives the same result as the optimal codes when the baseline is set short enough (Madam). For longer baselines destripers (Springtide and Madam) require less computing resources but deliver a noisier map.

  6. On the modelling of gyroplane flight dynamics

    Science.gov (United States)

    Houston, Stewart; Thomson, Douglas

    2017-01-01

    The study of the gyroplane, with a few exceptions, is largely neglected in the literature which is indicative of a niche configuration limited to the sport and recreational market where resources are limited. However the contemporary needs of an informed population of owners and constructors, as well as the possibility of a wider application of such low-cost rotorcraft in other roles, suggests that an examination of the mathematical modelling requirements for the study of gyroplane flight mechanics is timely. Rotorcraft mathematical modelling has become stratified in three levels, each one defining the inclusion of various layers of complexity added to embrace specific modelling features as well as an attempt to improve fidelity. This paper examines the modelling of gyroplane flight mechanics in the context of this complexity, and shows that relatively simple formulations are adequate for capturing most aspects of gyroplane trim, stability and control characteristics. In particular the conventional 6 degree-of-freedom model structure is suitable for the synthesis of models from flight test data as well as being the framework for reducing the order of the higher levels of modelling. However, a high level of modelling can be required to mimic some aspects of behaviour observed in data gathered from flight experiments and even then can fail to capture other details. These limitations are addressed in the paper. It is concluded that the mathematical modelling of gyroplanes for the simulation and analysis of trim, stability and control presents no special difficulty and the conventional techniques, methods and formulations familiar to the rotary-wing community are directly applicable.

  7. Flight Testing an Iced Business Jet for Flight Simulation Model Validation

    Science.gov (United States)

    Ratvasky, Thomas P.; Barnhart, Billy P.; Lee, Sam; Cooper, Jon

    2007-01-01

    A flight test of a business jet aircraft with various ice accretions was performed to obtain data to validate flight simulation models developed through wind tunnel tests. Three types of ice accretions were tested: pre-activation roughness, runback shapes that form downstream of the thermal wing ice protection system, and a wing ice protection system failure shape. The high fidelity flight simulation models of this business jet aircraft were validated using a software tool called "Overdrive." Through comparisons of flight-extracted aerodynamic forces and moments to simulation-predicted forces and moments, the simulation models were successfully validated. Only minor adjustments in the simulation database were required to obtain adequate match, signifying the process used to develop the simulation models was successful. The simulation models were implemented in the NASA Ice Contamination Effects Flight Training Device (ICEFTD) to enable company pilots to evaluate flight characteristics of the simulation models. By and large, the pilots confirmed good similarities in the flight characteristics when compared to the real airplane. However, pilots noted pitch up tendencies at stall with the flaps extended that were not representative of the airplane and identified some differences in pilot forces. The elevator hinge moment model and implementation of the control forces on the ICEFTD were identified as a driver in the pitch ups and control force issues, and will be an area for future work.

  8. Building A Flight Control System For A Modelled Aircraft

    OpenAIRE

    Garratt, Paul William; Rushton, Andrew; Yilmaz, Esat

    2004-01-01

    Abstract. We modelled an aircraft based on the Airbus A320 and constructed a synthesisable flight control system. The novel feature was the use of C and VHDL, Very High Speed Inte-grated Circuit Design Language, to allow the flight control system to reside in a Field Pro-grammable Gate Array in a model aircraft or an Uninhabited Aerial Vehicle. The simulator models axial, normal, transverse, pitch, roll and yaw movements. The flight control system has automatic manoeuvre envelope protection a...

  9. New modeling approach for bounding flight in birds.

    Science.gov (United States)

    Sachs, Gottfried; Lenz, Jakob

    2011-12-01

    A new modeling approach is presented which accounts for the unsteady motion features and dynamics characteristics of bounding flight. For this purpose, a realistic mathematical model is developed to describe the flight dynamics of a bird with regard to a motion which comprises flapping and bound phases involving acceleration and deceleration as well as, simultaneously, pull-up and push-down maneuvers. Furthermore, a mathematical optimization method is used for determining that bounding flight mode which yields the minimum energy expenditure per range. Thus, it can be shown to what extent bounding flight is aerodynamically superior to continuous flapping flight, yielding a reduction in the energy expenditure in the speed range practically above the maximum range speed. Moreover, the role of the body lift for the efficiency of bounding flight is identified and quantified. Introducing an appropriate non-dimensionalization of the relations describing the bird's flight dynamics, results of generally valid nature are derived for the addressed items.

  10. Modeling human response errors in synthetic flight simulator domain

    Science.gov (United States)

    Ntuen, Celestine A.

    1992-01-01

    This paper presents a control theoretic approach to modeling human response errors (HRE) in the flight simulation domain. The human pilot is modeled as a supervisor of a highly automated system. The synthesis uses the theory of optimal control pilot modeling for integrating the pilot's observation error and the error due to the simulation model (experimental error). Methods for solving the HRE problem are suggested. Experimental verification of the models will be tested in a flight quality handling simulation.

  11. Unsteady aerodynamics modeling for flight dynamics application

    Science.gov (United States)

    Wang, Qing; He, Kai-Feng; Qian, Wei-Qi; Zhang, Tian-Jiao; Cheng, Yan-Qing; Wu, Kai-Yuan

    2012-02-01

    In view of engineering application, it is practicable to decompose the aerodynamics into three components: the static aerodynamics, the aerodynamic increment due to steady rotations, and the aerodynamic increment due to unsteady separated and vortical flow. The first and the second components can be presented in conventional forms, while the third is described using a one-order differential equation and a radial-basis-function (RBF) network. For an aircraft configuration, the mathematical models of 6-component aerodynamic coefficients are set up from the wind tunnel test data of pitch, yaw, roll, and coupled yawroll large-amplitude oscillations. The flight dynamics of an aircraft is studied by the bifurcation analysis technique in the case of quasi-steady aerodynamics and unsteady aerodynamics, respectively. The results show that: (1) unsteady aerodynamics has no effect upon the existence of trim points, but affects their stability; (2) unsteady aerodynamics has great effects upon the existence, stability, and amplitudes of periodic solutions; and (3) unsteady aerodynamics changes the stable regions of trim points obviously. Furthermore, the dynamic responses of the aircraft to elevator deflections are inspected. It is shown that the unsteady aerodynamics is beneficial to dynamic stability for the present aircraft. Finally, the effects of unsteady aerodynamics on the post-stall maneuverability are analyzed by numerical simulation.

  12. Unsteady aerodynamics modeling for flight dynamics application

    Institute of Scientific and Technical Information of China (English)

    Qing Wang; Kai-Feng He; Wei-Qi Qian; Tian-Jiao Zhang; Yan-Qing Cheng; Kai-Yuan Wu

    2012-01-01

    In view of engineering application,it is practicable to decompose the aerodynamics into three components:the static aerodynamics,the aerodynamic increment due to steady rotations,and the aerodynamic increment due to unsteady separated and vortical flow.The first and the second components can be presented in conventional forms,while the third is described using a one-order differential equation and a radial-basis-function (RBF) network. For an aircraft configuration,the mathematical models of 6-component aerodynamic coefficients are set up from the wind tunnel test data of pitch,yaw,roll,and coupled yawroll large-amplitude oscillations.The flight dynamics of an aircraft is studied by the bifurcation analysis technique in the case of quasi-steady aerodynamics and unsteady aerodynamics,respectively.The results show that:(1) unsteady aerodynamics has no effect upon the existence of trim points,but affects their stability; (2) unsteady aerodynamics has great effects upon the existence,stability,and amplitudes of periodic solutions; and (3) unsteady aerodynamics changes the stable regions of trim points obviously.Furthermore,the dynamic responses of the aircraft to elevator deflections are inspected.It is shown that the unsteady aerodynamics is beneficial to dynamic stability for the present aircraft.Finally,the effects of unsteady aerodynamics on the post-stall maneuverability are analyzed by numerical simulation.

  13. The modeling of miniature UAV flight visualization simulation platform

    Science.gov (United States)

    Li, Dong-hui; Li, Xin; Yang, Le-le; Li, Xiong

    2015-12-01

    This paper combines virtual technology with visualization visual simulation theory, construct the framework of visual simulation platform, apply open source software FlightGear simulator combined with GoogleEarth design a small UAV flight visual simulation platform. Using software AC3D to build 3D models of aircraft and complete the model loading based on XML configuration, the design and simulation of visualization modeling visual platform is presented. By using model-driven and data transforming in FlightGear , the design of data transmission module is realized based on Visual Studio 2010 development platform. Finally combined with GoogleEarth it can achieve the tracking and display.

  14. Torsional balloon flight line oscillations: Comparison of modelling to flight data

    Science.gov (United States)

    Aubin, François; Bayman, Benjamin; Hanany, Shaul; Franco, Hugo; Marsh, Justin; Didier, Joy; Miller, Amber D.

    2017-08-01

    During the EBEX2013 long duration flight the payload was free to rotate in azimuth. The observed azimuth motion consisted of a superposition of full rotations with a period of 10-30 min and oscillatory motion with an amplitude of tens of degrees, average period of 79 s, and period dispersion of 12 s. We interpret the full rotations as induced by slow rotations of the balloon and the shorter period oscillatory motion as due to torsional oscillations of the flight line. We derive the torsional stiffness of the flight line using the bifilar pendulum model and apply it to the flight line of the EBEX2013 payload. We find a torsional spring constant of 36 kg m2/s2 corresponding to a period of 58 s. We conclude that the bifilar model, which accounts for the geometry of the flight line but neglects all material properties, predicts a stiffness and period that are 45% larger and 25% shorter than those observed. It is useful to have a simple, easy to use, coarse approximation for the torsional constant of the flight line.

  15. Motion perception modelling in flight simulation

    NARCIS (Netherlands)

    Groen, E.L.; Hosman, R.J.A.W.; Bos, J.E.; Dominicus, J.W.

    2004-01-01

    Motion cueing algorithms are indispensable to transform aircraft motions into simulator motions. Usually, such algorithms apply to the whole flight envelope. Since a motion base should stay within its six degrees of freedom workspace, the parameter settings necessarily involve concessions, which may

  16. Developing a Model for Solving the Flight Perturbation Problem

    Directory of Open Access Journals (Sweden)

    Amirreza Nickkar

    2015-02-01

    Full Text Available Purpose: In the aviation and airline industry, crew costs are the second largest direct operating cost next to the fuel costs. But unlike the fuel costs, a considerable portion of the crew costs can be saved through optimized utilization of the internal resources of an airline company. Therefore, solving the flight perturbation scheduling problem, in order to provide an optimized schedule in a comprehensive manner that covered all problem dimensions simultaneously, is very important. In this paper, we defined an integrated recovery model as that which is able to recover aircraft and crew dimensions simultaneously in order to produce more economical solutions and create fewer incompatibilities between the decisions. Design/methodology/approach: Current research is performed based on the development of one of the flight rescheduling models with disruption management approach wherein two solution strategies for flight perturbation problem are presented: Dantzig-Wolfe decomposition and Lagrangian heuristic. Findings: According to the results of this research, Lagrangian heuristic approach for the DW-MP solved the problem optimally in all known cases. Also, this strategy based on the Dantig-Wolfe decomposition manage to produce a solution within an acceptable time (Under 1 Sec. Originality/value: This model will support the decisions of the flight controllers in the operation centers for the airlines. When the flight network faces a problem the flight controllers achieve a set of ranked answers using this model thus, applying crew’s conditions in the proposed model caused this model to be closer to actual conditions.

  17. Optimization models for flight test scheduling

    Science.gov (United States)

    Holian, Derreck

    with restriction removal is based on heuristic approaches to support the reality of flight test in both solution space and computational time. Exact methods for yielding an optimized solution will be discussed however they are not directly applicable to the flight test problem and therefore have not been included in the system.

  18. Predicting migratory flight altitudes by physiological migration models

    NARCIS (Netherlands)

    Liechti, F.; Klaassen, M.R.J.; Bruderer, B.

    2000-01-01

    Using the altitudinal profiles of wind, temperature, pressure, and humidity in three flight models, we tried to explain the altitudinal distributions of nocturnal migrants recorded by radar above a desert in southern Israel. In the simplest model, only the tailwind component was used as a predictor

  19. PHARAO Laser Source Flight Model: Design and Performances

    CERN Document Server

    Lévèque, Thomas; Esnault, François-Xavier; Delaroche, Christophe; Massonnet, Didier; Grosjean, Olivier; Buffe, Fabrice; Torresi, Patrizia; Bomer, Thierry; Pichon, Alexandre; Béraud, Pascal; Lelay, Jean-Pierre; Thomin, Stéphane; Laurent, Philippe

    2015-01-01

    In this paper, we describe the design and the main performances of the PHARAO laser source flight model. PHARAO is a laser cooled cesium clock specially designed for operation in space and the laser source is one of the main sub-systems. The flight model presented in this work is the first remote-controlled laser system designed for spaceborne cold atom manipulation. The main challenges arise from mechanical compatibility with space constraints, which impose a high level of compactness, a low electric power consumption, a wide range of operating temperature and a vacuum environment. We describe the main functions of the laser source and give an overview of the main technologies developed for this instrument. We present some results of the qualification process. The characteristics of the laser source flight model, and their impact on the clock performances, have been verified in operational conditions.

  20. PHARAO laser source flight model: Design and performances

    Energy Technology Data Exchange (ETDEWEB)

    Lévèque, T., E-mail: thomas.leveque@cnes.fr; Faure, B.; Esnault, F. X.; Delaroche, C.; Massonnet, D.; Grosjean, O.; Buffe, F.; Torresi, P. [Centre National d’Etudes Spatiales, 18 avenue Edouard Belin, 31400 Toulouse (France); Bomer, T.; Pichon, A.; Béraud, P.; Lelay, J. P.; Thomin, S. [Sodern, 20 Avenue Descartes, 94451 Limeil-Brévannes (France); Laurent, Ph. [LNE-SYRTE, CNRS, UPMC, Observatoire de Paris, 61 avenue de l’Observatoire, 75014 Paris (France)

    2015-03-15

    In this paper, we describe the design and the main performances of the PHARAO laser source flight model. PHARAO is a laser cooled cesium clock specially designed for operation in space and the laser source is one of the main sub-systems. The flight model presented in this work is the first remote-controlled laser system designed for spaceborne cold atom manipulation. The main challenges arise from mechanical compatibility with space constraints, which impose a high level of compactness, a low electric power consumption, a wide range of operating temperature, and a vacuum environment. We describe the main functions of the laser source and give an overview of the main technologies developed for this instrument. We present some results of the qualification process. The characteristics of the laser source flight model, and their impact on the clock performances, have been verified in operational conditions.

  1. On numerical modeling of animal swimming and flight

    Science.gov (United States)

    Deng, Hong-Bin; Xu, Yuan-Qing; Chen, Duan-Duan; Dai, Hu; Wu, Jian; Tian, Fang-Bao

    2013-12-01

    Aquatic and aerial animals have developed their superior and complete mechanisms of swimming and flight. These mechanisms bring excellent locomotion performances to natural creatures, including high efficiency, long endurance ability, high maneuverability and low noise, and can potentially provide inspiration for the design of the man-made vehicles. As an efficient research approach, numerical modeling becomes more and more important in studying the mechanisms of swimming and flight. This review is focused on assessing the recent progress in numerical techniques of solving animal swimming and flight problems. According to the complexity of the problems considered, numerical studies are classified into five stages, of which the main characteristics and the numerical strategies are described and discussed. In addition, the body-conformal mesh, Cartesian-mesh, overset-grid, and meshfree methods are briefly introduced. Finally, several open issues in numerical modeling in this field are highlighted.

  2. Modelling of Airship Flight Mechanics by the Projection Equivalent Method

    OpenAIRE

    Frantisek Jelenciak; Michael Gerke; Ulrich Borgolte

    2015-01-01

    This article describes the projection equivalent method (PEM) as a specific and relatively simple approach for the modelling of aircraft dynamics. By the PEM it is possible to obtain a mathematic al model of the aerodynamic forces and momentums acting on different kinds of aircraft during flight. For the PEM, it is a characteristic of it that - in principle - it provides an acceptable regression model of aerodynamic forces and momentums which exhibits reasonable and plausible behaviour from a...

  3. Model Based Analysis and Test Generation for Flight Software

    Science.gov (United States)

    Pasareanu, Corina S.; Schumann, Johann M.; Mehlitz, Peter C.; Lowry, Mike R.; Karsai, Gabor; Nine, Harmon; Neema, Sandeep

    2009-01-01

    We describe a framework for model-based analysis and test case generation in the context of a heterogeneous model-based development paradigm that uses and combines Math- Works and UML 2.0 models and the associated code generation tools. This paradigm poses novel challenges to analysis and test case generation that, to the best of our knowledge, have not been addressed before. The framework is based on a common intermediate representation for different modeling formalisms and leverages and extends model checking and symbolic execution tools for model analysis and test case generation, respectively. We discuss the application of our framework to software models for a NASA flight mission.

  4. UAV Formation Flight Based on Nonlinear Model Predictive Control

    Directory of Open Access Journals (Sweden)

    Zhou Chao

    2012-01-01

    Full Text Available We designed a distributed collision-free formation flight control law in the framework of nonlinear model predictive control. Formation configuration is determined in the virtual reference point coordinate system. Obstacle avoidance is guaranteed by cost penalty, and intervehicle collision avoidance is guaranteed by cost penalty combined with a new priority strategy.

  5. Time-of-flight estimation based on covariance models

    NARCIS (Netherlands)

    van der Heijden, Ferdinand; Tuquerres, G.; Regtien, Paulus P.L.

    We address the problem of estimating the time-of-flight (ToF) of a waveform that is disturbed heavily by additional reflections from nearby objects. These additional reflections cause interference patterns that are difficult to predict. The introduction of a model for the reflection in terms of a

  6. A Maneuvering Flight Noise Model for Helicopter Mission Planning

    Science.gov (United States)

    Greenwood, Eric; Rau, Robert; May, Benjamin; Hobbs, Christopher

    2015-01-01

    A new model for estimating the noise radiation during maneuvering flight is developed in this paper. The model applies the Quasi-Static Acoustic Mapping (Q-SAM) method to a database of acoustic spheres generated using the Fundamental Rotorcraft Acoustics Modeling from Experiments (FRAME) technique. A method is developed to generate a realistic flight trajectory from a limited set of waypoints and is used to calculate the quasi-static operating condition and corresponding acoustic sphere for the vehicle throughout the maneuver. By using a previously computed database of acoustic spheres, the acoustic impact of proposed helicopter operations can be rapidly predicted for use in mission-planning. The resulting FRAME-QS model is applied to near-horizon noise measurements collected for the Bell 430 helicopter undergoing transient pitch up and roll maneuvers, with good agreement between the measured data and the FRAME-QS model.

  7. A Flight Dynamic Model of Aircraft Spinning

    Science.gov (United States)

    1990-06-01

    Australia, Library Australian Airlines, Library Qantas Airways Limited Hawker de Havilland Aust. Pty Ltd, Victoria, Library Hawker de Havilland Aust. Pty...3. MARTIN, C.A. ; Modelling Aircraft Dynamics. ARL-AERO-TECH- MEMO-400 July 1988 4. HULTBERG, R.S. ; Rotary Balance Data and Analysis for the

  8. Video analysis of the flight of a model aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Tarantino, Giovanni; Fazio, Claudio, E-mail: giovanni.tarantino19@unipa.it, E-mail: claudio.fazio@unipa.it [UOP-PERG (University of Palermo Physics Education Research Group), Dipartimento di Fisica, Universita di Palermo, Palermo (Italy)

    2011-11-15

    A video-analysis software tool has been employed in order to measure the steady-state values of the kinematics variables describing the longitudinal behaviour of a radio-controlled model aircraft during take-off, climbing and gliding. These experimental results have been compared with the theoretical steady-state configurations predicted by the phugoid model for longitudinal flight. A comparison with the parameters and performance of the full-size aircraft has also been outlined.

  9. Vestibular models for design and evaluation of flight simulator motion

    Science.gov (United States)

    Bussolari, S. R.; Sullivan, R. B.; Young, L. R.

    1986-01-01

    The use of spatial orientation models in the design and evaluation of control systems for motion-base flight simulators is investigated experimentally. The development of a high-fidelity motion drive controller using an optimal control approach based on human vestibular models is described. The formulation and implementation of the optimal washout system are discussed. The effectiveness of the motion washout system was evaluated by studying the response of six motion washout systems to the NASA/AMES Vertical Motion Simulator for a single dash-quick-stop maneuver. The effects of the motion washout system on pilot performance and simulator acceptability are examined. The data reveal that human spatial orientation models are useful for the design and evaluation of flight simulator motion fidelity.

  10. Modelling of Airship Flight Mechanics by the Projection Equivalent Method

    Directory of Open Access Journals (Sweden)

    Frantisek Jelenciak

    2015-12-01

    Full Text Available This article describes the projection equivalent method (PEM as a specific and relatively simple approach for the modelling of aircraft dynamics. By the PEM it is possible to obtain a mathematic al model of the aerodynamic forces and momentums acting on different kinds of aircraft during flight. For the PEM, it is a characteristic of it that -in principle - it provides an acceptable regression model of aerodynamic forces and momentums which exhibits reasonable and plausible behaviour from a dynamics viewpoint. The principle of this method is based on applying Newton's mechanics, which are then combined with a specific form of the finite element method to cover additional effects. The main advantage of the PEM is that it is not necessary to carry out measurements in a wind tunnel for the identification of the model's parameters. The plausible dynamical behaviour of the model can be achieved by specific correction parameters, which can be determined on the basis of experimental data obtained during the flight of the aircraft. In this article, we present the PEM as applied to an airship as well as a comparison of the data calculated by the PEM and experimental flight data.

  11. Dynamic flight stability of a hovering model dragonfly.

    Science.gov (United States)

    Liang, Bin; Sun, Mao

    2014-05-07

    The longitudinal dynamic flight stability of a model dragonfly at hovering flight is studied, using the method of computational fluid dynamics to compute the stability derivatives and the techniques of eigenvalue and eigenvector analysis for solving the equations of motion. Three natural modes of motion are identified for the hovering flight: one unstable oscillatory mode, one stable fast subsidence mode and one stable slow subsidence mode. The flight is dynamically unstable owing to the unstable oscillatory mode. The instability is caused by a pitch-moment derivative with respect to horizontal velocity. The damping force and moment derivatives (with respect to horizontal and vertical velocities and pitch-rotational velocity, respectively) weaken the instability considerably. The aerodynamic interaction between the forewing and the hindwing does not have significant effect on the stability properties. The dragonfly has similar stability derivatives, hence stability properties, to that of a one-wing-pair insect at normal hovering, but there are differences in how the derivatives are produced because of the highly inclined stroke plane of the dragonfly.

  12. Modelling of Airship Flight Mechanics by the Projection Equivalent Method

    Directory of Open Access Journals (Sweden)

    Frantisek Jelenciak

    2015-12-01

    Full Text Available This article describes the projection equivalent method (PEM as a specific and relatively simple approach for the modelling of aircraft dynamics. By the PEM it is possible to obtain a mathematic al model of the aerodynamic forces and momentums acting on different kinds of aircraft during flight. For the PEM, it is a characteristic of it that - in principle - it provides an acceptable regression model of aerodynamic forces and momentums which exhibits reasonable and plausible behaviour from a dynamics viewpoint. The principle of this method is based on applying Newton's mechanics, which are then combined with a specific form of the finite element method to cover additional effects. The main advantage of the PEM is that it is not necessary to carry out measurements in a wind tunnel for the identification of the model’s parameters. The plausible dynamical behaviour of the model can be achieved by specific correction parameters, which can be determined on the basis of experimental data obtained during the flight of the aircraft. In this article, we present the PEM as applied to an airship as well as a comparison of the data calculated by the PEM and experimental flight data.

  13. Intelligent modeling and identification of aircraft nonlinear flight

    Institute of Scientific and Technical Information of China (English)

    Alireza Roudbari; Fariborz Saghafi

    2014-01-01

    In this paper, a new approach has been proposed to identify and model the dynamics of a highly maneuverable fighter aircraft through artificial neural networks (ANNs). In general, air-craft flight dynamics is considered as a nonlinear and coupled system whose modeling through ANNs, unlike classical approaches, does not require any aerodynamic or propulsion information and a few flight test data seem sufficient. In this study, for identification and modeling of the aircraft dynamics, two known structures of internal and external recurrent neural networks (RNNs) and a proposed structure called hybrid combined recurrent neural network have been used and compared. In order to improve the training process, an appropriate evolutionary method has been applied to simultaneously train and optimize the parameters of ANNs. In this research, it has been shown that six ANNs each with three inputs and one output, trained by flight test data, can model the dynamic behavior of the highly maneuverable aircraft with acceptable accuracy and without any priori knowledge about the system.

  14. Modeling of preventive maintenance changes influence upon flight safety indexes

    Directory of Open Access Journals (Sweden)

    А.В. Гончаренко

    2004-03-01

    Full Text Available  It is considered a simplified model of connection between the catastrophic events flow frequency and both preventive maintenance changes periodicity and diagnosis depth of aviation equipment. It is deduced specific formulas for computing the changes and diagnostics parameters influence upon the values of both the catastrophic events flow frequency and technical-economical control factor criterion of flight safety levels.

  15. Testing of a Buran flight-model fuel cell

    Science.gov (United States)

    Schautz, M.; Dudley, G.; Baron, F.; Popov, V.; Pospelov, B.

    A demonstration test program has been performed at European Space Research & Technology Center (ESTEC) on a flight-model Russian 'Photon' fuel cell. The tests, conducted at various power levels up to 23 kW, included current/voltage characteristics, transient behavior, autothermal startup, and impedance measurements. In addition, the product water and the purge gas were analyzed. All test goals were met and no electrochemical limitations were apparent.

  16. Modeling methods for high-fidelity rotorcraft flight mechanics simulation

    Science.gov (United States)

    Mansur, M. Hossein; Tischler, Mark B.; Chaimovich, Menahem; Rosen, Aviv; Rand, Omri

    1992-01-01

    The cooperative effort being carried out under the agreements of the United States-Israel Memorandum of Understanding is discussed. Two different models of the AH-64 Apache Helicopter, which may differ in their approach to modeling the main rotor, are presented. The first model, the Blade Element Model for the Apache (BEMAP), was developed at Ames Research Center, and is the only model of the Apache to employ a direct blade element approach to calculating the coupled flap-lag motion of the blades and the rotor force and moment. The second model was developed at the Technion-Israel Institute of Technology and uses an harmonic approach to analyze the rotor. The approach allows two different levels of approximation, ranging from the 'first harmonic' (similar to a tip-path-plane model) to 'complete high harmonics' (comparable to a blade element approach). The development of the two models is outlined and the two are compared using available flight test data.

  17. Aircraft automatic flight control system with model inversion

    Science.gov (United States)

    Smith, G. A.; Meyer, George

    1990-01-01

    A simulator study was conducted to verify the advantages of a Newton-Raphson model-inversion technique as a design basis for an automatic trajectory control system in an aircraft with highly nonlinear characteristics. The simulation employed a detailed mathematical model of the aerodynamic and propulsion system performance characteristics of a vertical-attitude takeoff and landing tactical aircraft. The results obtained confirm satisfactory control system performance over a large portion of the flight envelope. System response to wind gusts was satisfactory for various plausible combinations of wind magnitude and direction.

  18. Aircraft automatic flight control system with model inversion

    Science.gov (United States)

    Smith, G. A.; Meyer, George

    1990-01-01

    A simulator study was conducted to verify the advantages of a Newton-Raphson model-inversion technique as a design basis for an automatic trajectory control system in an aircraft with highly nonlinear characteristics. The simulation employed a detailed mathematical model of the aerodynamic and propulsion system performance characteristics of a vertical-attitude takeoff and landing tactical aircraft. The results obtained confirm satisfactory control system performance over a large portion of the flight envelope. System response to wind gusts was satisfactory for various plausible combinations of wind magnitude and direction.

  19. A Method to Identify Flight Obstacles on Digital Surface Model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Min; LIN Xinggang; SUN Shouyu; WANG Youzhi

    2005-01-01

    In modern low-altitude terrain-following guidance, a constructing method of the digital surface model (DSM) is presented in the paper to reduce the threat to flying vehicles of tall surface features for safe flight. The relationship between an isolated obstacle size and the intervals of vertical- and cross-section in the DSM model is established. The definition and classification of isolated obstacles are proposed, and a method for determining such isolated obstacles in the DSM model is given. The simulation of a typical urban district shows that when the vertical- and cross-section DSM intervals are between 3 m and 25 m, the threat to terrain-following flight at low-altitude is reduced greatly, and the amount of data required by the DSM model for monitoring in real time a flying vehicle is also smaller. Experiments show that the optimal results are for an interval of 12.5 m in the vertical- and cross-sections in the DSM model, with a 1:10 000 DSM scale grade.

  20. Time of Flight Transients in the Dipolar Glass Model

    OpenAIRE

    2013-01-01

    Using Monte Carlo simulation we investigated time of flight current transients predicted by the dipolar glass model for a random spatial distribution of hopping centers. Behavior of the carrier drift mobility was studied at room temperature over a broad range of electric field and sample thickness. A flat plateau followed by $j\\propto t^{-2}$ current decay is the most common feature of the simulated transients. Poole-Frenkel mobility field dependence was confirmed over 5 to 200 V/$\\mu$m as we...

  1. Real-Time Onboard Global Nonlinear Aerodynamic Modeling from Flight Data

    Science.gov (United States)

    Brandon, Jay M.; Morelli, Eugene A.

    2014-01-01

    Flight test and modeling techniques were developed to accurately identify global nonlinear aerodynamic models onboard an aircraft. The techniques were developed and demonstrated during piloted flight testing of an Aermacchi MB-326M Impala jet aircraft. Advanced piloting techniques and nonlinear modeling techniques based on fuzzy logic and multivariate orthogonal function methods were implemented with efficient onboard calculations and flight operations to achieve real-time maneuver monitoring and analysis, and near-real-time global nonlinear aerodynamic modeling and prediction validation testing in flight. Results demonstrated that global nonlinear aerodynamic models for a large portion of the flight envelope were identified rapidly and accurately using piloted flight test maneuvers during a single flight, with the final identified and validated models available before the aircraft landed.

  2. MODELING OF THE FLIGHT CREW’S TRAINING PROCESSES ON SIMULATORS IN THE INTERESTS OF GUARANTEED Flight SAFETY

    Directory of Open Access Journals (Sweden)

    I. G. Sokhin

    2014-01-01

    Full Text Available The paper covers the problem how to control flight crew training on simulators to ensure the fulfillment requirements for the quality of their activity in training non-standard situations which can happen in flight. It is shown that the existing methodology of training pilots on simulators does not ensure the quality of their activity in those non-standard situations. The paper puts forward an adaptive control method (АМC-method of the simulator training of flight crews using mathematical modeling the states of their operator competences. The main advantage of the new method is the possibility to obtain statistical quality indicators of flight crew activity in non-standard situations and, thereby, to control the fulfillment of prescribed requirements for safety and reliability of space missions.

  3. Comparison of induced velocity models for helicopter flight mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.E.; Houston, S.S.

    2002-07-01

    Modeling of rotor-induced velocity receives continued attention in the literature as the rotorcraft community addresses limitations in the fidelity of simulations of helicopter stability, control, and handling qualities. A comparison is presented of results obtained using a rigid-blade rotor-fuselage model configured with two induced velocity models: a conventional, first-order, finite state, dynamic inflow model and a wake model that solves a vorticity transport equation on a computational mesh enclosing the rotorcraft. Differences between the two models are quantified by comparing predictions of trimmed rotor blade flap, lag and feather angles, airframe pitch and roll attitudes, cross-coupling derivatives, response to control inputs, and airframe vibration. Results are presented in the context of measurements taken on a Puma aircraft in steady flight from hover to high speed. More accurate predictions of the cross-coupling derivatives, response to control, and airframe vibration obtained using the vorticity transport model suggest that incorporation of real flowfield effects is important to extending the bandwidth of applicability of helicopter simulation models. Unexpectedly small differences in some of the trim predictions obtained using the two wake models suggest that an overall improvement in simulation fidelity may not be achieved without equivalent attention to the rotor dynamic model. (Author)

  4. Identification of a coupled flapping/inflow model for the PUMA helicopter from flight test data

    Science.gov (United States)

    Du Val, Ronald; Bruhis, Ofer; Green, John

    1989-01-01

    A model validation procedure is applied to a coupled flapping/inflow model of a PUMA helicopter blade. The structure of the baseline model is first established. Model structure and flight test data are checked for consistency. Parameters of the model are then identified from the flight test data.

  5. 76 FR 9265 - Special Conditions: Gulfstream Model GVI Airplane; Electronic Flight Control System: Control...

    Science.gov (United States)

    2011-02-17

    ... Model GVI Airplane; Electronic Flight Control System: Control Surface Position Awareness AGENCY: Federal... transport category airplanes. These design features include an electronic flight control system. The... The GVI has an electronic flight control system and no direct coupling from the cockpit controller to...

  6. Constructing a Stochastic Model of Bumblebee Flights from Experimental Data

    CERN Document Server

    Lenz, Friedrich; Klages, Rainer

    2013-01-01

    The movement of organisms is subject to a multitude of influences of widely varying character: from the bio-mechanics of the individual, over the interaction with the complex environment many animals live in, to evolutionary pressure and energy constraints. As the number of factors is large, it is very hard to build comprehensive movement models. Even when movement patterns in simple environments are analysed, the organisms can display very complex behaviours. While for largely undirected motion or long observation times the dynamics can sometimes be described by isotropic random walks, usually the directional persistence due to a preference to move forward has to be accounted for, e.g., by a correlated random walk. In this paper we generalise these descriptions to a model in terms of stochastic differential equations of Langevin type, which we use to analyse experimental search flight data of foraging bumblebees. Using parameter estimates we discuss the differences and similarities to correlated random walks...

  7. Flight Dynamics and Control of Elastic Hypersonic Vehicles Uncertainty Modeling

    Science.gov (United States)

    Chavez, Frank R.; Schmidt, David K.

    1994-01-01

    It has been shown previously that hypersonic air-breathing aircraft exhibit strong aeroelastic/aeropropulsive dynamic interactions. To investigate these, especially from the perspective of the vehicle dynamics and control, analytical expressions for key stability derivatives were derived, and an analysis of the dynamics was performed. In this paper, the important issue of model uncertainty, and the appropriate forms for representing this uncertainty, is addressed. It is shown that the methods suggested in the literature for analyzing the robustness of multivariable feedback systems, which as a prerequisite to their application assume particular forms of model uncertainty, can be difficult to apply on real atmospheric flight vehicles. Also, the extent to which available methods are conservative is demonstrated for this class of vehicle dynamics.

  8. Cryogenic characterization of the Planck sorption cooler system flight model

    Energy Technology Data Exchange (ETDEWEB)

    Morgante, G; Terenzi, L; Butler, C; Mandolesi, N [INAF - IASF Bologna, via P. Gobetti 101, 40129 Bologna (Italy); Pearson, D; Wilson, P; Hernandez, B; Wade, L [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena California 91109 (United States); Melot, F; Stassi, P [Laboratoire de Physique Subatomique et de Cosmologie 53 Avenue des Martyrs, 38026 Grenoble Cedex (France); Gregorio, A [Dipartimento di Fisica, Universita degli Studi di Trieste, via Valerio 2 - I-34127 Trieste (Italy); Bersanelli, M, E-mail: morgante@iasfbo.inaf.i [Dipartimento di Fisica, Universita degli Studi di Milano, via Celoria 16, - I20133 Milano (Italy)

    2009-12-15

    Two continuous closed-cycle hydrogen Joule-Thomson (J-T) sorption coolers have been fabricated and assembled by the Jet Propulsion Laboratory (JPL) for the European Space Agency (ESA) Planck mission. Each refrigerator has been designed to provide a total of {approx} 1W of cooling power at two instrument interfaces: they directly cool the Planck Low Frequency Instrument (LFI) around 20K while providing a pre-cooling stage for a 4 K J-T mechanical refrigerator for the High Frequency Instrument (HFI). After sub-system level validation at JPL, the cryocoolers have been delivered to ESA in 2005. In this paper we present the results of the cryogenic qualification and test campaigns of the Nominal Unit on the flight model spacecraft performed at the CSL (Centre Spatial de Liege) facilities in 2008. Test results in terms of input power, cooling power, temperature, and temperature fluctuations over the flight allowable ranges for these interfaces are reported and analyzed with respect to mission requirements.

  9. Flight Dynamics Simulation Modeling and Control of a Large Flexible Tiltrotor Aircraft

    Science.gov (United States)

    2014-09-01

    TECHNICAL REPORT CR-RDMR-AF-14-01 FLIGHT DYNAMICS SIMULATION MODELING AND CONTROL OF A LARGE FLEXIBLE TILTROTOR AIRCRAFT...September 2014 3. REPORT TYPE AND DATES COVERED Final 4. TITLE AND SUBTITLE Flight Dynamics Simulation Modeling and Control of a Large Flexible...18 298-102 i/ii (Blank) FLIGHT DYNAMICS SIMULATION MODELING AND CONTROL OF A LARGE FLEXIBLE TILTROTOR AIRCRAFT by Ondrej Juhasz Dissertation

  10. Cross-Compiler for Modeling Space-Flight Systems

    Science.gov (United States)

    James, Mark

    2007-01-01

    Ripples is a computer program that makes it possible to specify arbitrarily complex space-flight systems in an easy-to-learn, high-level programming language and to have the specification automatically translated into LibSim, which is a text-based computing language in which such simulations are implemented. LibSim is a very powerful simulation language, but learning it takes considerable time, and it requires that models of systems and their components be described at a very low level of abstraction. To construct a model in LibSim, it is necessary to go through a time-consuming process that includes modeling each subsystem, including defining its fault-injection states, input and output conditions, and the topology of its connections to other subsystems. Ripples makes it possible to describe the same models at a much higher level of abstraction, thereby enabling the user to build models faster and with fewer errors. Ripples can be executed in a variety of computers and operating systems, and can be supplied in either source code or binary form. It must be run in conjunction with a Lisp compiler.

  11. Modeling Flight: The Role of Dynamically Scaled Free-Flight Models in Support of NASA's Aerospace Programs

    Science.gov (United States)

    Chambers, Joseph

    2010-01-01

    The state of the art in aeronautical engineering has been continually accelerated by the development of advanced analysis and design tools. Used in the early design stages for aircraft and spacecraft, these methods have provided a fundamental understanding of physical phenomena and enabled designers to predict and analyze critical characteristics of new vehicles, including the capability to control or modify unsatisfactory behavior. For example, the relatively recent emergence and routine use of extremely powerful digital computer hardware and software has had a major impact on design capabilities and procedures. Sophisticated new airflow measurement and visualization systems permit the analyst to conduct micro- and macro-studies of properties within flow fields on and off the surfaces of models in advanced wind tunnels. Trade studies of the most efficient geometrical shapes for aircraft can be conducted with blazing speed within a broad scope of integrated technical disciplines, and the use of sophisticated piloted simulators in the vehicle development process permits the most important segment of operations the human pilot to make early assessments of the acceptability of the vehicle for its intended mission. Knowledgeable applications of these tools of the trade dramatically reduce risk and redesign, and increase the marketability and safety of new aerospace vehicles. Arguably, one of the more viable and valuable design tools since the advent of flight has been testing of subscale models. As used herein, the term "model" refers to a physical article used in experimental analyses of a larger full-scale vehicle. The reader is probably aware that many other forms of mathematical and computer-based models are also used in aerospace design; however, such topics are beyond the intended scope of this document. Model aircraft have always been a source of fascination, inspiration, and recreation for humans since the earliest days of flight. Within the scientific

  12. Nonlinear Aerodynamic Modeling From Flight Data Using Advanced Piloted Maneuvers and Fuzzy Logic

    Science.gov (United States)

    Brandon, Jay M.; Morelli, Eugene A.

    2012-01-01

    Results of the Aeronautics Research Mission Directorate Seedling Project Phase I research project entitled "Nonlinear Aerodynamics Modeling using Fuzzy Logic" are presented. Efficient and rapid flight test capabilities were developed for estimating highly nonlinear models of airplane aerodynamics over a large flight envelope. Results showed that the flight maneuvers developed, used in conjunction with the fuzzy-logic system identification algorithms, produced very good model fits of the data, with no model structure inputs required, for flight conditions ranging from cruise to departure and spin conditions.

  13. Propeller aircraft interior noise model. II - Scale-model and flight-test comparisons

    Science.gov (United States)

    Willis, C. M.; Mayes, W. H.

    1987-01-01

    A program for predicting the sound levels inside propeller driven aircraft arising from sidewall transmission of airborne exterior noise is validated through comparisons of predictions with both scale-model test results and measurements obtained in flight tests on a turboprop aircraft. The program produced unbiased predictions for the case of the scale-model tests, with a standard deviation of errors of about 4 dB. For the case of the flight tests, the predictions revealed a bias of 2.62-4.28 dB (depending upon whether or not the data for the fourth harmonic were included) and the standard deviation of the errors ranged between 2.43 and 4.12 dB. The analytical model is shown to be capable of taking changes in the flight environment into account.

  14. Modeling and software implementation of flight system for simulator of a new fighter

    Institute of Scientific and Technical Information of China (English)

    SUI Cheng-cheng; YANG Yong-tian; JIA Rong-zhen

    2004-01-01

    Real-time modeling and simulation of flight system are the key parts of simulator. After describing the architecture of simulator for a newer fighter, author presents the composition of flight system and its mathematic models. In this paper, aircraft is regarded as an elastic flight body. And a new integrated algorithm which can remedy the shortcoming of Euler method and four-element method is used to calculate the Eulerian angles of aircraft. Finally, the software implementation of the flight system is given in the paper.

  15. Marshall Space Flight Center surface modeling and grid generation applications

    Science.gov (United States)

    Williams, Robert W.; Benjamin, Theodore G.; Cornelison, Joni W.

    1995-03-01

    The Solid Rocket Motors (SRM) used by NASA to propel the Space Shuttle employ gimballing nozzles as a means for vehicular guidance during launch and ascent. Gimballing a nozzle renders the pressure field of the exhaust gases nonaxisymmetric. This has two effects: (1) it exerts a torque and side load on the nozzle; and (2) the exhaust gases flow circumferentially in the aft-dome region, thermally loading the flexible boot, case-to-nozzle joint, and casing insulation. The use of CFD models to simulate such flows is imperative in order to assess SRM design. The grids for these problems were constructed by obtaining information from drawings and tabulated coordinates. The 2D axisymmetric grids were designed and generated using the EZ-Surf and GEN2D surface and grid generation codes. These 2D grids were solved using codes such as FDNS, GASP, and MINT. These axisymmetric grids were rotated around the center-line to form 3D nongimballed grids. These were then gimballed around the pivot point and the gaps or overlaps resurfaced to obtain the final domains, which contained approximately 366,000 grid points. The 2D solutions were then rotated and manipulated as appropriate for geometry and used as initial guesses in the final solution. The analyses were used in answering questions about flight criteria.

  16. Cryogenic characterization of the Planck sorption cooler system flight model

    CERN Document Server

    Morgante, G; Melot, F; Stassi, P; Terenzi, L; Wilson, P; Hernandez, B; Wade, L; Gregorio, A; Bersanelli, M; Butler, C; Mandolesi, N; 10.1088/1748-0221/4/12/T12016

    2009-01-01

    This paper is part of the Prelaunch status LFI papers published on JINST: http://www.iop.org/EJ/journal/-page=extra.proc5/1748-0221 Two continuous closed-cycle hydrogen Joule-Thomson (J-T) sorption coolers have been fabricated and assembled by the Jet Propulsion Laboratory (JPL) for the European Space Agency (ESA) Planck mission. Each refrigerator has been designed to provide a total of ~ 1W of cooling power at two instrument interfaces: they directly cool the Planck Low Frequency Instrument (LFI) around 20K while providing a pre-cooling stage for a 4 K J-T mechanical refrigerator for the High Frequency Instrument (HFI). After sub-system level validation at JPL, the cryocoolers have been delivered to ESA in 2005. In this paper we present the results of the cryogenic qualification and test campaigns of the Nominal Unit on the flight model spacecraft performed at the CSL (Centre Spatial de Liege) facilities in 2008. Test results in terms of input power, cooling power, temperature, and temperature fluctuations o...

  17. Through the eyes of a bird: modelling visually guided obstacle flight.

    Science.gov (United States)

    Lin, Huai-Ti; Ros, Ivo G; Biewener, Andrew A

    2014-07-01

    Various flight navigation strategies for birds have been identified at the large spatial scales of migratory and homing behaviours. However, relatively little is known about close-range obstacle negotiation through cluttered environments. To examine obstacle flight guidance, we tracked pigeons (Columba livia) flying through an artificial forest of vertical poles. Interestingly, pigeons adjusted their flight path only approximately 1.5 m from the forest entry, suggesting a reactive mode of path planning. Combining flight trajectories with obstacle pole positions, we reconstructed the visual experience of the pigeons throughout obstacle flights. Assuming proportional-derivative control with a constant delay, we searched the relevant parameter space of steering gains and visuomotor delays that best explained the observed steering. We found that a pigeon's steering resembles proportional control driven by the error angle between the flight direction and the desired opening, or gap, between obstacles. Using this pigeon steering controller, we simulated obstacle flights and showed that pigeons do not simply steer to the nearest opening in the direction of flight or destination. Pigeons bias their flight direction towards larger visual gaps when making fast steering decisions. The proposed behavioural modelling method converts the obstacle avoidance behaviour into a (piecewise) target-aiming behaviour, which is better defined and understood. This study demonstrates how such an approach decomposes open-loop free-flight behaviours into components that can be independently evaluated.

  18. Instrumentation and data acquisition electronics for free-flight drop model testing

    Science.gov (United States)

    Carraway, Preston I., III

    1988-01-01

    This paper presents instrumentation and data acquisition electronics techniques used in free-flight drop model testing at the NASA Langley Research Center. Free-flight drop model testing is a technique for conducting complex aircraft controls research using reduced scale models of experimental aircraft. An introduction to the Free-Flight Drop Model Program is presented first. This is followed by a description of the recently upgraded airborne and ground based instrumentation and data acquisition electronics. Lastly current and future development efforts and opportunities are discussed.

  19. The MICROSCOPE Inertial sensors and their flight models electronics

    Science.gov (United States)

    Touboul, Pierre; Boulanger, Damien; Liorzou, Françoise

    2012-07-01

    Dedicated space inertial sensors have been developed for the payload of the MICROSCOPE mission which scientific objective is the test of the universality of free fall at level better than 10-15. This accuracy requires the operation of four inertial sensors on board a specific drag-free satellite, exhibiting resolution of better than 1 femto-g for data integrating period over 20 orbits. Such an outstanding resolution requires the fine electrostatic servo-control of each sensor test mass motion, free of any perturbation along its six degrees of freedom. In addition to a very accurate geometrical sensor core, highly performing electronics architecture is necessary to provide the measurement of the weak electrostatic forces and torques applied to the mass. Capacitive sensing provides the linear and attitude motion of the mass with respect to gold coated electrodes silica parts. Charges are controlled on the electrodes all around the mass to generate adequate electrical field and so electrostatic pressures in order to maintain the mass motionless with respect to the instrument structure. Digital control laws are implemented to deal with both the instrument operation flexibility and the preservation of the weak position sensor noise. The flight model electronics units have been produced and tested. All characteristics have been verified as well as the thermal sensitivities. Description of these units and test results are presented in the paper. These electronics provide not only the scientific data for the General Relativity test but also the data for the satellite orbit and attitude control. The satellite is now under production for a launch in 2016.

  20. Development of an Autonomous Flight Control System for Small Size Unmanned Helicopter Based on Dynamical Model

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    It is devoted to the development of an autonomous flight control system for small size unmanned helicopter based on dynamical model. At first, the mathematical model of a small size helicopter is described. After that simple but effective MTCV control algorithm was proposed. The whole flight control algorithm is composed of two parts:orientation controller based on the model for rotation dynamics and a robust position controller for a double integrator. The MTCV block is also used to achieve translation velocity control. To demonstrate the performance of the presented algorithm, simulation results and results achieved in real flight experiments were presented.

  1. Highly integrated digital electronic control: Digital flight control, aircraft model identification, and adaptive engine control

    Science.gov (United States)

    Baer-Riedhart, Jennifer L.; Landy, Robert J.

    1987-01-01

    The highly integrated digital electronic control (HIDEC) program at NASA Ames Research Center, Dryden Flight Research Facility is a multiphase flight research program to quantify the benefits of promising integrated control systems. McDonnell Aircraft Company is the prime contractor, with United Technologies Pratt and Whitney Aircraft, and Lear Siegler Incorporated as major subcontractors. The NASA F-15A testbed aircraft was modified by the HIDEC program by installing a digital electronic flight control system (DEFCS) and replacing the standard F100 (Arab 3) engines with F100 engine model derivative (EMD) engines equipped with digital electronic engine controls (DEEC), and integrating the DEEC's and DEFCS. The modified aircraft provides the capability for testing many integrated control modes involving the flight controls, engine controls, and inlet controls. This paper focuses on the first two phases of the HIDEC program, which are the digital flight control system/aircraft model identification (DEFCS/AMI) phase and the adaptive engine control system (ADECS) phase.

  2. Modeling flight attendants' exposure to secondhand smoke in commercial aircraft: historical trends from 1955 to 1989.

    Science.gov (United States)

    Liu, Ruiling; Dix-Cooper, Linda; Hammond, S Katharine

    2015-01-01

    Flight attendants were exposed to elevated levels of secondhand smoke (SHS) in commercial aircraft when smoking was allowed on planes. During flight attendants' working years, their occupational SHS exposure was influenced by various factors, including the prevalence of active smokers on planes, fliers' smoking behaviors, airplane flight load factors, and ventilation systems. These factors have likely changed over the past six decades and would affect SHS concentrations in commercial aircraft. However, changes in flight attendants' exposure to SHS have not been examined in the literature. This study estimates the magnitude of the changes and the historic trends of flight attendants' SHS exposure in U.S. domestic commercial aircraft by integrating historical changes of contributing factors. Mass balance models were developed and evaluated to estimate flight attendants' exposure to SHS in passenger cabins, as indicated by two commonly used tracers (airborne nicotine and particulate matter (PM)). Monte Carlo simulations integrating historical trends and distributions of influence factors were used to simulate 10,000 flight attendants' exposure to SHS on commercial flights from 1955 to 1989. These models indicate that annual mean SHS PM concentrations to which flight attendants were exposed in passenger cabins steadily decreased from approximately 265 μg/m(3) in 1955 and 1960 to 93 μg/m(3) by 1989, and airborne nicotine exposure among flight attendants also decreased from 11.1 μg/m(3) in 1955 to 6.5 μg/m(3) in 1989. Using duration of employment as an indicator of flight attendants' cumulative occupational exposure to SHS in epidemiological studies would inaccurately assess their lifetime exposures and thus bias the relationship between the exposure and health effects. This historical trend should be considered in future epidemiological studies.

  3. The Integrated Medical Model: A Decision Support Tool for In-flight Crew Health Care

    Science.gov (United States)

    Butler, Doug

    2009-01-01

    This viewgraph presentation reviews the development of an Integrated Medical Model (IMM) decision support tool for in-flight crew health care safety. Clinical methods, resources, and case scenarios are also addressed.

  4. Scaled Model Technology for Flight Research of General Aviation Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Our proposed future Phase II activities are aimed at developing a scientifically based "tool box" for flight research using scaled models. These tools will be of...

  5. A Stochastic Model for the Landing Dispersion of Hazard Detection and Avoidance Capable Flight Systems

    Science.gov (United States)

    Witte, L.

    2014-06-01

    To support landing site assessments for HDA-capable flight systems and to facilitate trade studies between the potential HDA architectures versus the yielded probability of safe landing a stochastic landing dispersion model has been developed.

  6. LDSD POST2 Modeling Enhancements in Support of SFDT-2 Flight Operations

    Science.gov (United States)

    White, Joseph; Bowes, Angela L.; Dutta, Soumyo; Ivanov, Mark C.; Queen, Eric M.

    2016-01-01

    Program to Optimize Simulated Trajectories II (POST2) was utilized to develop trajectory simulations characterizing all flight phases from drop to splashdown for the Low-Density Supersonic Decelerator (LDSD) project's first and second Supersonic Flight Dynamics Tests (SFDT-1 and SFDT-2) which took place June 28, 2014 and June 8, 2015, respectively. This paper describes the modeling improvements incorporated into the LDSD POST2 simulations since SFDT-1 and presents how these modeling updates affected the predicted SFDT-2 performance and sensitivity to the mission design. The POST2 simulation flight dynamics support during the SFDT-2 launch, operations, and recovery is also provided.

  7. A Direct-Fire Trajectory Model for Supersonic, Transonic, and Subsonic Projectile Flight

    Science.gov (United States)

    2014-07-01

    motions of the projectile about the trajectory due to the angular motion of the projectile . For a stable projectile , these motions are typically small...A Direct-Fire Trajectory Model for Supersonic, Transonic, and Subsonic Projectile Flight by Paul Weinacht ARL-TR-6998 July 2014...Direct-Fire Trajectory Model for Supersonic, Transonic, and Subsonic Projectile Flight Paul Weinacht Weapons and Materials Research Directorate, ARL

  8. Modelling of XCO2 Surfaces Based on Flight Tests of TanSat Instruments

    Directory of Open Access Journals (Sweden)

    Li Li Zhang

    2016-11-01

    Full Text Available The TanSat carbon satellite is to be launched at the end of 2016. In order to verify the performance of its instruments, a flight test of TanSat instruments was conducted in Jilin Province in September, 2015. The flight test area covered a total area of about 11,000 km2 and the underlying surface cover included several lakes, forest land, grassland, wetland, farmland, a thermal power plant and numerous cities and villages. We modeled the column-average dry-air mole fraction of atmospheric carbon dioxide (XCO2 surface based on flight test data which measured the near- and short-wave infrared (NIR reflected solar radiation in the absorption bands at around 760 and 1610 nm. However, it is difficult to directly analyze the spatial distribution of XCO2 in the flight area using the limited flight test data and the approximate surface of XCO2, which was obtained by regression modeling, which is not very accurate either. We therefore used the high accuracy surface modeling (HASM platform to fill the gaps where there is no information on XCO2 in the flight test area, which takes the approximate surface of XCO2 as its driving field and the XCO2 observations retrieved from the flight test as its optimum control constraints. High accuracy surfaces of XCO2 were constructed with HASM based on the flight’s observations. The results showed that the mean XCO2 in the flight test area is about 400 ppm and that XCO2 over urban areas is much higher than in other places. Compared with OCO-2’s XCO2, the mean difference is 0.7 ppm and the standard deviation is 0.95 ppm. Therefore, the modelling of the XCO2 surface based on the flight test of the TanSat instruments fell within an expected and acceptable range.

  9. Modelling of XCO2 Surfaces Based on Flight Tests of TanSat Instruments

    Science.gov (United States)

    Zhang, Li Li; Yue, Tian Xiang; Wilson, John P.; Wang, Ding Yi; Zhao, Na; Liu, Yu; Liu, Dong Dong; Du, Zheng Ping; Wang, Yi Fu; Lin, Chao; Zheng, Yu Quan; Guo, Jian Hong

    2016-01-01

    The TanSat carbon satellite is to be launched at the end of 2016. In order to verify the performance of its instruments, a flight test of TanSat instruments was conducted in Jilin Province in September, 2015. The flight test area covered a total area of about 11,000 km2 and the underlying surface cover included several lakes, forest land, grassland, wetland, farmland, a thermal power plant and numerous cities and villages. We modeled the column-average dry-air mole fraction of atmospheric carbon dioxide (XCO2) surface based on flight test data which measured the near- and short-wave infrared (NIR) reflected solar radiation in the absorption bands at around 760 and 1610 nm. However, it is difficult to directly analyze the spatial distribution of XCO2 in the flight area using the limited flight test data and the approximate surface of XCO2, which was obtained by regression modeling, which is not very accurate either. We therefore used the high accuracy surface modeling (HASM) platform to fill the gaps where there is no information on XCO2 in the flight test area, which takes the approximate surface of XCO2 as its driving field and the XCO2 observations retrieved from the flight test as its optimum control constraints. High accuracy surfaces of XCO2 were constructed with HASM based on the flight’s observations. The results showed that the mean XCO2 in the flight test area is about 400 ppm and that XCO2 over urban areas is much higher than in other places. Compared with OCO-2’s XCO2, the mean difference is 0.7 ppm and the standard deviation is 0.95 ppm. Therefore, the modelling of the XCO2 surface based on the flight test of the TanSat instruments fell within an expected and acceptable range. PMID:27809272

  10. Evaluation of Fast-Time Wake Vortex Models using Wake Encounter Flight Test Data

    Science.gov (United States)

    Ahmad, Nashat N.; VanValkenburg, Randal L.; Bowles, Roland L.; Limon Duparcmeur, Fanny M.; Gloudesman, Thijs; van Lochem, Sander; Ras, Eelco

    2014-01-01

    This paper describes a methodology for the integration and evaluation of fast-time wake models with flight data. The National Aeronautics and Space Administration conducted detailed flight tests in 1995 and 1997 under the Aircraft Vortex Spacing System Program to characterize wake vortex decay and wake encounter dynamics. In this study, data collected during Flight 705 were used to evaluate NASA's fast-time wake transport and decay models. Deterministic and Monte-Carlo simulations were conducted to define wake hazard bounds behind the wake generator. The methodology described in this paper can be used for further validation of fast-time wake models using en-route flight data, and for determining wake turbulence constraints in the design of air traffic management concepts.

  11. A Multiple Agent Model of Human Performance in Automated Air Traffic Control and Flight Management Operations

    Science.gov (United States)

    Corker, Kevin; Pisanich, Gregory; Condon, Gregory W. (Technical Monitor)

    1995-01-01

    A predictive model of human operator performance (flight crew and air traffic control (ATC)) has been developed and applied in order to evaluate the impact of automation developments in flight management and air traffic control. The model is used to predict the performance of a two person flight crew and the ATC operators generating and responding to clearances aided by the Center TRACON Automation System (CTAS). The purpose of the modeling is to support evaluation and design of automated aids for flight management and airspace management and to predict required changes in procedure both air and ground in response to advancing automation in both domains. Additional information is contained in the original extended abstract.

  12. PICASSO VISION instrument design, engineering model test results, and flight model development status

    Science.gov (United States)

    Näsilä, Antti; Holmlund, Christer; Mannila, Rami; Näkki, Ismo; Ojanen, Harri J.; Akujärvi, Altti; Saari, Heikki; Fussen, Didier; Pieroux, Didier; Demoulin, Philippe

    2016-10-01

    PICASSO - A PICo-satellite for Atmospheric and Space Science Observations is an ESA project led by the Belgian Institute for Space Aeronomy, in collaboration with VTT Technical Research Centre of Finland Ltd, Clyde Space Ltd. (UK) and Centre Spatial de Liège (BE). The test campaign for the engineering model of the PICASSO VISION instrument, a miniaturized nanosatellite spectral imager, has been successfully completed. The test results look very promising. The proto-flight model of VISION has also been successfully integrated and it is waiting for the final integration to the satellite platform.

  13. Basic Flight Criteria - Pack Off - Model XC-120

    Science.gov (United States)

    1949-05-01

    uhj,,- ........ ASIC FLIGHT CRITERIA. PAOK O- PJART 11-D-i b. Power On ?or nower on conditions values Of qht will q ve.ry with angle of attack and with...00711 GZ,7 x 0 as CZT 0 from Part II-AP-9-e reference (1) . ŕVT VT_ _____________________________nr_______________T__________ MIL, R 1 11, 1) AIR S’ICt...CH.Kwxl Ply ArPUAVYM MI hATE I May 19.49 Sub)B .... . ASIC TLIGHTT GRIT.•RIA -. PAO 0 ... .. .... REVISED. - , 0" A•- •i , Il-l... I I _ _ .1 !f" • l I 4

  14. Oceanic Area System Improvement Study (OASIS). Volume VIII. Central East Pacific Region Flight Cost Model Results.

    Science.gov (United States)

    1981-09-01

    RI ~ 4, 4, 5 - .4 u.n a a . 5g 4, ~ .4 0 8.41.4 .4 41 __________________________________ U 4, 1 .44,~5 44j~ 1 0 a ~ a 4,~1 4 ~.4N ~𔃾 41 - -4 0 U 4 -4...costs of the uncorrected ’error were somewhat mitigated by the Flight Tracking Model’s resolution of the conflict on the now- congested lower flight

  15. Use of animal models for space flight physiology studies, with special focus on the immune system

    Science.gov (United States)

    Sonnenfeld, Gerald

    2005-01-01

    Animal models have been used to study the effects of space flight on physiological systems. The animal models have been used because of the limited availability of human subjects for studies to be carried out in space as well as because of the need to carry out experiments requiring samples and experimental conditions that cannot be performed using humans. Experiments have been carried out in space using a variety of species, and included developmental biology studies. These species included rats, mice, non-human primates, fish, invertebrates, amphibians and insects. The species were chosen because they best fit the experimental conditions required for the experiments. Experiments with animals have also been carried out utilizing ground-based models that simulate some of the effects of exposure to space flight conditions. Most of the animal studies have generated results that parallel the effects of space flight on human physiological systems. Systems studied have included the neurovestibular system, the musculoskeletal system, the immune system, the neurological system, the hematological system, and the cardiovascular system. Hindlimb unloading, a ground-based model of some of the effects of space flight on the immune system, has been used to study the effects of space flight conditions on physiological parameters. For the immune system, exposure to hindlimb unloading has been shown to results in alterations of the immune system similar to those observed after space flight. This has permitted the development of experiments that demonstrated compromised resistance to infection in rodents maintained in the hindlimb unloading model as well as the beginning of studies to develop countermeasures to ameliorate or prevent such occurrences. Although there are limitations to the use of animal models for the effects of space flight on physiological systems, the animal models should prove very valuable in designing countermeasures for exploration class missions of the future.

  16. A novel flight surgeon training model at a joint military and civilian surgical residency program.

    Science.gov (United States)

    DeSoucy, Erik S; Zakaluzny, Scott A; Galante, Joseph M

    2017-07-01

    Graduating military preliminary interns are often required to fill flight surgeon billets. General surgery preliminary interns get experience evaluating surgical and trauma patients, but receive very little training in primary care and flight medicine. At a joint military and civilian training program, we developed a supplemental curriculum to help transition our interns into flight medicine. From 2013 to 2016, we developed a lecture series focused on aerospace medicine, primary care, and specialty topics including dermatology, ophthalmology, orthopedics, pediatrics, psychiatry, and women's health. During the 2016 iteration attended by 10 interns, pre- and post-participation 10-item Likert scale surveys were administered. Questions focused on perceived preparedness for primary care role and overall enthusiasm for flight medicine. Open-ended surveys from 2013 to 2016 were also used to gauge the effect of the curriculum. The composite number of agreement responses (indicating increased comfort with presented material) increased 63% after course completion. Disagreement responses and neutral responses decreased 78% and 30%, respectively. Open-ended surveys from 14 participants showed an overall positive impression of the curriculum with all indicating it aided their transition to flight medicine. Survey responses indicate an overall perceived benefit from participation in the curriculum with more confidence in primary care topics and improved transition to a flight medicine tour. This model for supplemental aerospace medicine and primary care didactics should be integrated into any residency program responsible for training military preliminary interns who may serve as flight surgeons. Published by Elsevier Inc.

  17. Initial virtual flight test for a dynamically similar aircraft model with control augmentation system

    Directory of Open Access Journals (Sweden)

    Linliang Guo

    2017-04-01

    Full Text Available To satisfy the validation requirements of flight control law for advanced aircraft, a wind tunnel based virtual flight testing has been implemented in a low speed wind tunnel. A 3-degree-of-freedom gimbal, ventrally installed in the model, was used in conjunction with an actively controlled dynamically similar model of aircraft, which was equipped with the inertial measurement unit, attitude and heading reference system, embedded computer and servo-actuators. The model, which could be rotated around its center of gravity freely by the aerodynamic moments, together with the flow field, operator and real time control system made up the closed-loop testing circuit. The model is statically unstable in longitudinal direction, and it can fly stably in wind tunnel with the function of control augmentation of the flight control laws. The experimental results indicate that the model responds well to the operator’s instructions. The response of the model in the tests shows reasonable agreement with the simulation results. The difference of response of angle of attack is less than 0.5°. The effect of stability augmentation and attitude control law was validated in the test, meanwhile the feasibility of virtual flight test technique treated as preliminary evaluation tool for advanced flight vehicle configuration research was also verified.

  18. Development of a Multi-Disciplinary Aerothermostructural Model Applicable to Hypersonic Flight

    Science.gov (United States)

    Kostyk, Chris; Risch, Tim

    2013-01-01

    The harsh and complex hypersonic flight environment has driven design and analysis improvements for many years. One of the defining characteristics of hypersonic flight is the coupled, multi-disciplinary nature of the dominant physics. In an effect to examine some of the multi-disciplinary problems associated with hypersonic flight engineers at the NASA Dryden Flight Research Center developed a non-linear 6 degrees-of-freedom, full vehicle simulation that includes the necessary model capabilities: aerothermal heating, ablation, and thermal stress solutions. Development of the tool and results for some investigations will be presented. Requirements and improvements for future work will also be reviewed. The results of the work emphasize the need for a coupled, multi-disciplinary analysis to provide accurate

  19. Model Used for Dynamic Stability Studies in 5 Foot Free-Flight Tunnel

    Science.gov (United States)

    1938-01-01

    Model mounted in the 5-Foot Free-Flight Tunnel. This wind tunnel was used to study the dynamic stability and control characteristics of aircraft in flight. The test section of the tunnel could be tilted to permit the model to fly without restraint when sufficient lift was produced by its wings. During free-flight tests, the tunnel test technique required two engineers. One engineer stood at the side of the test section and controlled the tunnel airspeed and tilt angle while attempting to maintain the airstream relative to the model. The second engineer controlled the airplane model remotely via small wires attached to control surface actuators. The pilot stood behind the tunnel propeller and viewed the rear of the model in flight and assessed its stability and control characteristics for various test conditions. His control box can be seen at the bottom of the picture. The tunnel was authorized in 1936 and was operational in April 1937. Construction cost was $120,000. This exploratory facility was superseded by a larger 12-ft free-flight tunnel in 1939.

  20. Bird Flight as a Model for a Course in Unsteady Aerodynamics

    Science.gov (United States)

    Jacob, Jamey; Mitchell, Jonathan; Puopolo, Michael

    2014-11-01

    Traditional unsteady aerodynamics courses at the graduate level focus on theoretical formulations of oscillating airfoil behavior. Aerodynamics students with a vision for understanding bird-flight and small unmanned aircraft dynamics desire to move beyond traditional flow models towards new and creative ways of appreciating the motion of agile flight systems. High-speed videos are used to record kinematics of bird flight, particularly barred owls and red-shouldered hawks during perching maneuvers, and compared with model aircraft performing similar maneuvers. Development of a perching glider and associated control laws to model the dynamics are used as a class project. Observations are used to determine what different species and sizes of birds share in their methods to approach a perch under similar conditions. Using fundamental flight dynamics, simplified models capable of predicting position, attitude, and velocity of the flier are developed and compared with the observations. By comparing the measured data from the videos and predicted and measured motions from the glider models, it is hoped that the students gain a better understanding of the complexity of unsteady aerodynamics and aeronautics and an appreciation for the beauty of avian flight.

  1. A queueing model of pilot decision making in a multi-task flight management situation

    Science.gov (United States)

    Walden, R. S.; Rouse, W. B.

    1977-01-01

    Allocation of decision making responsibility between pilot and computer is considered and a flight management task, designed for the study of pilot-computer interaction, is discussed. A queueing theory model of pilot decision making in this multi-task, control and monitoring situation is presented. An experimental investigation of pilot decision making and the resulting model parameters are discussed.

  2. Crime Modeling with Truncated Levy Flights and Effects of Police Patrol

    CERN Document Server

    Pan, Chaohao; Zhang, Yuqi; Geldner, Nathan; Wang, Chuntian; Wang, Li; Bertozzi, Andrea

    2016-01-01

    In this paper, we developed a truncated Levy flight model to study the crime dynamics. In the discrete case, our model allows criminals to perform long jumps in between committing crimes with a speed light. This is a more realistic extension of a pioneering random walk model by Short et. al and a Levy flight model thereafter in Chaturapruek, et al. We also derive a continuum limit and perform a stability analysis to study the formation of crime hotspots. Our model is more realistic than the Levy Flight Model, and provides an alternative to the Random Walk Model when the criminals can perform long jumps in between committing crimes. In the next step, we introduce patrolling police officers to our new model following that in. We examine the effects of police patrol when the police choose to adopt different strategies, including unbiased random walk, biased random walk, and truncated Levy flight. We evaluate the effectiveness of the police patrol with the number of crime events in a given time frame. With spatia...

  3. Cognitive modelling of pilot errors and error recovery in flight management tasks

    NARCIS (Netherlands)

    Lüdtke, A.; Osterloh, J.P.; Mioch, T.; Rister, F.; Looije, R.

    2009-01-01

    This paper presents a cognitive modelling approach to predict pilot errors and error recovery during the interaction with aircraft cockpit systems. The model allows execution of flight procedures in a virtual simulation environment and production of simulation traces. We present traces for the inter

  4. The rhesus monkey as a model for testing the immunological effects of space flight

    Science.gov (United States)

    Sonnenfeld, G.; Schaffar, L.; Schmitt, D. A.; Peres, C.; Miller, E. S.

    1994-08-01

    The Rhesus monkey has been proposed as a model for the effects of space flight on immunity. In order to determine the feasibility of the use of the Rhesus monkey as a model, we studied the use of Rhesus monkey cells for immunological procedures that have been shown to be affected by space flight in both rodents and humans. We have shown that both lymph node cells and peripheral blood leukocytes can be stained with monoclonal antibodies to detect the following surface markers: CD4, CD-8, Ia and surface immunoglobulin. Also, the level of Ia antigen expression was increased by treatment of the cells with human interferon-gamma. In addition, cells were induced to produce interferons and interleukins. Isolated neutrophils also demonstrated increased oxidative burst. These data indicate that the Rhesus monkey will be a useful model for space flight studies of immunity.

  5. Toward a Model-Based Approach to Flight System Fault Protection

    Science.gov (United States)

    Day, John; Murray, Alex; Meakin, Peter

    2012-01-01

    Fault Protection (FP) is a distinct and separate systems engineering sub-discipline that is concerned with the off-nominal behavior of a system. Flight system fault protection is an important part of the overall flight system systems engineering effort, with its own products and processes. As with other aspects of systems engineering, the FP domain is highly amenable to expression and management in models. However, while there are standards and guidelines for performing FP related analyses, there are not standards or guidelines for formally relating the FP analyses to each other or to the system hardware and software design. As a result, the material generated for these analyses are effectively creating separate models that are only loosely-related to the system being designed. Development of approaches that enable modeling of FP concerns in the same model as the system hardware and software design enables establishment of formal relationships that has great potential for improving the efficiency, correctness, and verification of the implementation of flight system FP. This paper begins with an overview of the FP domain, and then continues with a presentation of a SysML/UML model of the FP domain and the particular analyses that it contains, by way of showing a potential model-based approach to flight system fault protection, and an exposition of the use of the FP models in FSW engineering. The analyses are small examples, inspired by current real-project examples of FP analyses.

  6. Digital adaptive model following flight control. [using fighter aircraft mathematical model-following algorithm

    Science.gov (United States)

    Alag, G. S.; Kaufman, H.

    1974-01-01

    Simple mechanical linkages are often unable to cope with the many control problems associated with high performance aircraft maneuvering over a wide flight envelope. One procedure for retaining uniform handling qualities over such an envelope is to implement a digital adaptive controller. Towards such an implementation an explicit adaptive controller, which makes direct use of online parameter identification, has been developed and applied to the linearized equations of motion for a typical fighter aircraft. The system is composed of an online weighted least squares identifier, a Kalman state filter, and a single stage real model following control law. The corresponding control gains are readily adjustable in accordance with parameter changes to ensure asymptotic stability if the conditions for perfect model following are satisfied and stability in the sense of boundedness otherwise.

  7. Development of a Human Motor Model for the Evaluation of an Integrated Alerting and Notification Flight Deck System

    Science.gov (United States)

    Daiker, Ron; Schnell, Thomas

    2010-01-01

    A human motor model was developed on the basis of performance data that was collected in a flight simulator. The motor model is under consideration as one component of a virtual pilot model for the evaluation of NextGen crew alerting and notification systems in flight decks. This model may be used in a digital Monte Carlo simulation to compare flight deck layout design alternatives. The virtual pilot model is being developed as part of a NASA project to evaluate multiple crews alerting and notification flight deck configurations. Model parameters were derived from empirical distributions of pilot data collected in a flight simulator experiment. The goal of this model is to simulate pilot motor performance in the approach-to-landing task. The unique challenges associated with modeling the complex dynamics of humans interacting with the cockpit environment are discussed, along with the current state and future direction of the model.

  8. A computational model for estimating the mechanics of horizontal flapping flight in bats: model description and validation.

    Science.gov (United States)

    Watts, P; Mitchell, E J; Swartz, S M

    2001-08-01

    We combine three-dimensional descriptions of the movement patterns of the shoulder, elbow, carpus, third metacarpophalangeal joint and wingtip with a constant-circulation estimation of aerodynamic force to model the wing mechanics of the grey-headed flying fox (Pteropus poliocephalus) in level flight. Once rigorously validated, this computer model can be used to study diverse aspects of flight. In the model, we partitioned the wing into a series of chordwise segments and calculated the magnitude of segmental aerodynamic forces assuming an elliptical, spanwise distribution of circulation at the middle of the downstroke. The lift component of the aerodynamic force is typically an order of magnitude greater than the thrust component. The largest source of drag is induced drag, which is approximately an order of magnitude greater than body form and skin friction drag. Using this model and standard engineering beam theory, we calculate internal reaction forces, moments and stresses at the humeral and radial midshaft during flight. To assess the validity of our model, we compare the model-derived stresses with our previous in vivo empirical measurements of bone strain from P. poliocephalus in free flapping flight. Agreement between bone stresses from the simulation and those calculated from empirical strain measurements is excellent and suggests that the computer model captures a significant portion of the mechanics and aerodynamics of flight in this species.

  9. On characteristic modeling of a class of flight vehicles’attitude dynamics

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The characteristic modeling problem of flight vehicles’attitude dynamics is considered in this paper.In terms of the affine nonlinear system with triangle form of flight vehicles’attitude dynamics,a general method is presented to compress the dynamics into the characteristic model parameters,by introducing the time scale of nonlinear systems and a class of system states related compress functions.The parameter region and limit of the characteristic model are also given.From the given parameter region it is seen that the bound of the characteristic model parameters is dependent on the sampling period,the modeling error,the system order and the system change rate.The modeling error of the established characteristic model can be arbitrarily small according to the control precision,showing the difference between the characteristic model and other model reduction methods,that is,no system information is lost using this approach.On the basis of this modeling approach,the characteristic model of the flexible satellite attitude is established,as well as the bound and limit of the parameters,which sets a theoretical foundation for characteristic model based control design of flight vehicles.

  10. Control for going from hovering to small speed flight of a model insect

    Institute of Scientific and Technical Information of China (English)

    Jianghao Wu; Mao Sun

    2009-01-01

    The longitudinal steady-state control for going from hovering to small speed flight of a model insect is studied, using the method of computational fluid dynamics to compute the aerodynamic derivatives and the techniques based on the linear theories of stability and control for deter-mining the non-zero equilibrium points. Morphological and certain kinematical data of droneflies are used for the model insect. A change in the mean stroke angle (δφ) results in a horizontal forward or backward flight; a change in the stroke amplitude (δΦ) or a equal change in the down- and upstroke angles of attack (δα1) results in a vertical climb or decent; a proper combination of δφ and δΦ controls (or δφ and δα1 controls) can give a flight of any (small) speed in any desired direction.

  11. Dynamic modeling and ascent flight control of Ares-I Crew Launch Vehicle

    Science.gov (United States)

    Du, Wei

    This research focuses on dynamic modeling and ascent flight control of large flexible launch vehicles such as the Ares-I Crew Launch Vehicle (CLV). A complete set of six-degrees-of-freedom dynamic models of the Ares-I, incorporating its propulsion, aerodynamics, guidance and control, and structural flexibility, is developed. NASA's Ares-I reference model and the SAVANT Simulink-based program are utilized to develop a Matlab-based simulation and linearization tool for an independent validation of the performance and stability of the ascent flight control system of large flexible launch vehicles. A linearized state-space model as well as a non-minimum-phase transfer function model (which is typical for flexible vehicles with non-collocated actuators and sensors) are validated for ascent flight control design and analysis. This research also investigates fundamental principles of flight control analysis and design for launch vehicles, in particular the classical "drift-minimum" and "load-minimum" control principles. It is shown that an additional feedback of angle-of-attack can significantly improve overall performance and stability, especially in the presence of unexpected large wind disturbances. For a typical "non-collocated actuator and sensor" control problem for large flexible launch vehicles, non-minimum-phase filtering of "unstably interacting" bending modes is also shown to be effective. The uncertainty model of a flexible launch vehicle is derived. The robust stability of an ascent flight control system design, which directly controls the inertial attitude-error quaternion and also employs the non-minimum-phase filters, is verified by the framework of structured singular value (mu) analysis. Furthermore, nonlinear coupled dynamic simulation results are presented for a reference model of the Ares-I CLV as another validation of the feasibility of the ascent flight control system design. Another important issue for a single main engine launch vehicle is

  12. Flight dynamics modeling of a small ducted fan aerial vehicle based on parameter identification

    Institute of Scientific and Technical Information of China (English)

    Wang Zhengjie; Liu Zhijun; Fan Ningjun; Guo Meifang

    2013-01-01

    This paper presents a simple and useful modeling method to acquire a dynamics model of an aerial vehicle containing unknown parameters using mechanism modeling, and then to design different identification experiments to identify the parameters based on the sources and features of its unknown parameters. Based on the mathematical model of the aerial vehicle acquired by modeling and identification, a design for the structural parameters of the attitude control system is carried out, and the results of the attitude control flaps are verified by simulation experiments and flight tests of the aerial vehicle. Results of the mathematical simulation and flight tests show that the mathematical model acquired using parameter identification is comparatively accurate and of clear mechanics, and can be used as the reference and basis for the structural design.

  13. High-order state space simulation models of helicopter flight mechanics

    Science.gov (United States)

    Kim, Frederick D.; Celi, Roberto; Tischler, Mark B.

    1993-01-01

    This paper describes the formulation and validation of a high-order linearized mathematical model of helicopter flight mechanics, which includes rotor flap and lag degrees of freedom as well as inflow dynamics. The model is extracted numerically from an existing nonlinear, blade element, real-time simulation model. Extensive modifications in the formulation and solution process of the nonlinear model, required for a theoetically rigorous linearization, are described in detail. The validation results show that the linearized model successfully captures the coupled rotor-fuselage dynamics in the frequency band most critical for the design of advanced flight control systems. Additional results quantify the extent to which the order of the model can be reduced without loss of fidelity.

  14. Polychronous Interpretation of Synoptic, a Domain Specific Modeling Language for Embedded Flight-Software

    CERN Document Server

    Besnard, L; Ouy, J; Talpin, J -P; Bodeveix, J -P; Cortier, A; Pantel, M; Strecker, M; Garcia, G; Rugina, A; Buisson, J; Dagnat, F

    2010-01-01

    The SPaCIFY project, which aims at bringing advances in MDE to the satellite flight software industry, advocates a top-down approach built on a domain-specific modeling language named Synoptic. In line with previous approaches to real-time modeling such as Statecharts and Simulink, Synoptic features hierarchical decomposition of application and control modules in synchronous block diagrams and state machines. Its semantics is described in the polychronous model of computation, which is that of the synchronous language Signal.

  15. MATHEMATICAL MODEL OF AUTOMATIC FLIGHT OF POLIKOPTER UAV NAU PKF "AURORA"

    Directory of Open Access Journals (Sweden)

    Wang Bo

    2016-12-01

    Full Text Available Purpose: Development of mathematical and experimental models of polikopter UAV NAU PKF "Aurora" of oktakopter scheme for experimental flights in manual, semi-automatic and unmanned mode.                  Methods: 14/03/2016 - 21/03/2016 held a serіe of experiental flights (10 flights of 10 rats on altitude 700 meters on polіkopter (oktakopter NAU PKF "Aurora" in germetic kabіn with the study of his somatic,  nevrologіcal status after the flight. Flights also carried out with experimental animals on board for such a safety assessment. Results: The obtained logs of 'black box' of the autopilot indicate very small (almost invisible fluctuations in pitch, roll and yaw during the flight, minor variations on altitude during almost stationary hovering of polikopter at different altitudes, and fully adequate to movements and maneuvers of aircraft vibrations and parameters of these sensors. Discussion: In the course of these studies demonstrated experimentally the possibility of completely safe flight of the mammals (rats on polikopter vehicle, even in the open cockpit. With appropriate refinement possible in the future to raise the issue of the development and construction of passenger polikopter flyers for totally safe air transportation of people [6,7,8]. In terms of adverse mechanical effects on the human body (acceleration overload fluctuations, vibrations polikopter transport is safer and less harmful to the passengers than road transport, which is particularly important in the delivery of patient of neurosurgical, politravmatological, cardiologycal and critical care profile at critical condition in intensive care units and operating hospitals and medical centers.

  16. 78 FR 6195 - Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Flight Envelope Protection...

    Science.gov (United States)

    2013-01-30

    ... jet airplanes designed for corporate flight, fractional, charter, and private owner operations. The... turbofan engines mounted on aft fuselage pylons. Each engine produces approximately 6,540 pounds of thrust... function into the engine of the Model EMB-550 airplane. It has a full authority digital electronic...

  17. Stall Recovery in a Centrifuge-Based Flight Simulator With an Extended Aerodynamic Model

    NARCIS (Netherlands)

    Ledegang, W.D.; Groen, E.L.

    2015-01-01

    We investigated the performance of 12 airline pilots in recovering from an asymmetrical stall in a flight simulator featuring an extended aerodynamic model of a transport-category aircraft, and a centrifuge-based motion platform capable of generating enhanced buffet motion and g-cueing. All pilots h

  18. Prediction and simulator verification of state-space rotor modelling on helicopter manoeuvring flight

    NARCIS (Netherlands)

    Gori, R.; Gennaretti, M.; Pavel, M.D.; Stroosma, O.; Miletovic, I.

    2015-01-01

    Among the many fundamental components of a flight simulator, the mathematical representation of the vehicle dynamics stands out for complexity and importance. This is especially true for helicopters, for which the complex dynamics involved prevents simple models to be sufficiently accurate without t

  19. Unsteady Aerodynamic Models for Flight Control of Agile Micro Air Vehicles

    Science.gov (United States)

    2010-08-13

    AUG 2010 2. REPORT TYPE Final 3. DATES COVERED 01-02-2007 to 30-11-2009 4. TITLE AND SUBTITLE Unsteady Aerodynamic Models for Flight Control...non-physical. First, it is impossible to command in experiments or simulations, because it would correspond to a body instanta- neously dematerializing

  20. Model-Based GN and C Simulation and Flight Software Development for Orion Missions beyond LEO

    Science.gov (United States)

    Odegard, Ryan; Milenkovic, Zoran; Henry, Joel; Buttacoli, Michael

    2014-01-01

    For Orion missions beyond low Earth orbit (LEO), the Guidance, Navigation, and Control (GN&C) system is being developed using a model-based approach for simulation and flight software. Lessons learned from the development of GN&C algorithms and flight software for the Orion Exploration Flight Test One (EFT-1) vehicle have been applied to the development of further capabilities for Orion GN&C beyond EFT-1. Continuing the use of a Model-Based Development (MBD) approach with the Matlab®/Simulink® tool suite, the process for GN&C development and analysis has been largely improved. Furthermore, a model-based simulation environment in Simulink, rather than an external C-based simulation, greatly eases the process for development of flight algorithms. The benefits seen by employing lessons learned from EFT-1 are described, as well as the approach for implementing additional MBD techniques. Also detailed are the key enablers for improvements to the MBD process, including enhanced configuration management techniques for model-based software systems, automated code and artifact generation, and automated testing and integration.

  1. Markov Jump-Linear Performance Models for Recoverable Flight Control Computers

    Science.gov (United States)

    Zhang, Hong; Gray, W. Steven; Gonzalez, Oscar R.

    2004-01-01

    Single event upsets in digital flight control hardware induced by atmospheric neutrons can reduce system performance and possibly introduce a safety hazard. One method currently under investigation to help mitigate the effects of these upsets is NASA Langley s Recoverable Computer System. In this paper, a Markov jump-linear model is developed for a recoverable flight control system, which will be validated using data from future experiments with simulated and real neutron environments. The method of tracking error analysis and the plan for the experiments are also described.

  2. Video Analysis of the Flight of a Model Aircraft

    Science.gov (United States)

    Tarantino, Giovanni; Fazio, Claudio

    2011-01-01

    A video-analysis software tool has been employed in order to measure the steady-state values of the kinematics variables describing the longitudinal behaviour of a radio-controlled model aircraft during take-off, climbing and gliding. These experimental results have been compared with the theoretical steady-state configurations predicted by the…

  3. Video Analysis of the Flight of a Model Aircraft

    Science.gov (United States)

    Tarantino, Giovanni; Fazio, Claudio

    2011-01-01

    A video-analysis software tool has been employed in order to measure the steady-state values of the kinematics variables describing the longitudinal behaviour of a radio-controlled model aircraft during take-off, climbing and gliding. These experimental results have been compared with the theoretical steady-state configurations predicted by the…

  4. Mathematical modeling of the aerodynamic characteristics in flight dynamics

    Science.gov (United States)

    Tobak, M.; Chapman, G. T.; Schiff, L. B.

    1984-01-01

    Basic concepts involved in the mathematical modeling of the aerodynamic response of an aircraft to arbitrary maneuvers are reviewed. The original formulation of an aerodynamic response in terms of nonlinear functionals is shown to be compatible with a derivation based on the use of nonlinear functional expansions. Extensions of the analysis through its natural connection with ideas from bifurcation theory are indicated.

  5. Mathematical model for estimation of meteoroid dark flight trajectory

    Science.gov (United States)

    Vinnikov, V. V.; Gritsevich, M. I.; Turchak, L. I.

    2016-10-01

    This paper is concerned with mathematical model for numerical simulation of meteoroid dynamics. The simulations of bolide ballistics are carried out via hard sphere approximation. System of differential equations for movement and heat transfer is solved in Lagrange variables via Runge-Kutta methods. The drag force of atmospheric air is computed via Henderson formula, valid for wide ranges of Reynolds and Mach numbers. The parameters of surrounding gas are obtained from standard atmosphere model. The impact pressure is computed taking into account entropy jump through bow head shockwave and consequent isentropic deceleration of the flow in the vicinity of streamlined sphere. Meteoroid fragmentation is modeled as sequential division of parent body into two parts using random weighting coefficient for parent mass. The condition for fragmentation event occur when the hemisphere-averaged value of impact pressure exceeds the threshold of relative body strength, which nonlinearly depends on ration of initial meteoroid mass to current mass of considered fragment. To compute trajectory divergence for newly-formed splinters we introduce the repulsive force, dependent on impact pressure, cross sectional areas of mutually repulsing bodies and distances between them. The set of mathematical models is implemented as the program complex. Preliminary computational results show that fragmentation altitude, terminal velocities and maximum splinter masses are in good agreement with corresponding observations and measurements.

  6. Study of Mechanical Model of Sports Ball’S Flight Trajectory and Its Application

    Directory of Open Access Journals (Sweden)

    Xiaoyan Yu

    2013-05-01

    Full Text Available In order to resolve the controversy of ball games the placement problem fined on the other hand, to promote the teaching and training ball flight trajectory. Tennis is the main object of study, use of literature, mathematical statistics and experimental research methods and to establish an appropriate mathematical model, using MATLAB software to accurately determine the trajectory and impact point of the ball's flight, used in teaching, training and competition in. The conclusions show that the law, accurate data analysis using MATLAB software can simulate the flight of the ball moving on sports development has a very good help provide a new way of thinking for the in-depth study the pattern of winning ball games and similar sports teaching, training and selection of athletes is an important complementary and valuable.

  7. A wake bending unsteady dynamic inflow model of tiltrotor in conversion flight of tiltrotor aircraft

    Institute of Scientific and Technical Information of China (English)

    YUE HaiLong; XIA PinQi

    2009-01-01

    The aerodynamics, dynamic responses and aeroelasticity of tiltrotor aircraft in the tilting of rotor i.e.In conversion flight are extraordinarily complicated.The traditional quasi-steady assumption model can not reflect the unsteady aerodynamic problems in the tilting of rotor.The CFD method based on the vortex theory can get better results, but it consumes a lot of computing resources.In this paper, a wake bending dynamic inflow model of tilting rotor was established firstly based on the Peters-He dynamic inflow model used in helicopter.Then combining with the ONERA unsteady aerodynamic model, a wake bending unsteady dynamic inflow model of tilting rotor in conversion flight of tiltrotor aircraft was es-tablished.The wake bending unsteady dynamic inflow model of tilting rotor was verified by using the experimental data of an isolated rotor model in large angle pitching up maneuver and was used to calculate the dynamic responses of tilting rotor in conversion flight of a tiltrotor aircraft model.The calculated results were analyzed to be physically reasonable.

  8. A wake bending unsteady dynamic inflow model of tiltrotor in conversion flight of tiltrotor aircraft

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The aerodynamics, dynamic responses and aeroelasticity of tiltrotor aircraft in the tilting of rotor i.e. in conversion flight are extraordinarily complicated. The traditional quasi-steady assumption model can not reflect the unsteady aerodynamic problems in the tilting of rotor. The CFD method based on the vortex theory can get better results, but it consumes a lot of computing resources. In this paper, a wake bending dynamic inflow model of tilting rotor was established firstly based on the Peters-He dynamic inflow model used in helicopter. Then combining with the ONERA unsteady aerodynamic model, a wake bending unsteady dynamic inflow model of tilting rotor in conversion flight of tiltrotor aircraft was established. The wake bending unsteady dynamic inflow model of tilting rotor was verified by using the experimental data of an isolated rotor model in large angle pitching up maneuver and was used to calculate the dynamic responses of tilting rotor in conversion flight of a tiltrotor aircraft model. The calculated results were analyzed to be physically reasonable.

  9. A model for the human's use of visual field cues in nap-of-the-Earth flight

    Science.gov (United States)

    Hess, R. A.; Chan, K.

    1986-01-01

    A simple model is developed which describes the manner in which the human pilot may use visual field cues in controlling a vehicle in nap-of-the earth flight. The model is based upon the feedforward of information obtained from streamer patterns in the visual field to the inner-most loop of a multi-loop pilot/vehicle model. In this framework, the model is a logical extension of pursuit and preview models of the human operator which have appeared in the literature. Simulation and flight test data involving low-level helicopter flight tasks are applied to model development and validation.

  10. The use of vestibular models for design and evaluation of flight simulator motion

    Science.gov (United States)

    Bussolari, Steven R.; Young, Laurence R.; Lee, Alfred T.

    1989-01-01

    Quantitative models for the dynamics of the human vestibular system are applied to the design and evaluation of flight simulator platform motion. An optimal simulator motion control algorithm is generated to minimize the vector difference between perceived spatial orientation estimated in flight and in simulation. The motion controller has been implemented on the Vertical Motion Simulator at NASA Ames Research Center and evaluated experimentally through measurement of pilot performance and subjective rating during VTOL aircraft simulation. In general, pilot performance in a longitudinal tracking task (formation flight) did not appear to be sensitive to variations in platform motion condition as long as motion was present. However, pilot assessment of motion fidelity by means of a rating scale designed for this purpose, were sensitive to motion controller design. Platform motion generated with the optimal motion controller was found to be generally equivalent to that generated by conventional linear crossfeed washout. The vestibular models are used to evaluate the motion fidelity of transport category aircraft (Boeing 727) simulation in a pilot performance and simulator acceptability study at the Man-Vehicle Systems Research Facility at NASA Ames Research Center. Eighteen airline pilots, currently flying B-727, were given a series of flight scenarios in the simulator under various conditions of simulator motion. The scenarios were chosen to reflect the flight maneuvers that these pilots might expect to be given during a routine pilot proficiency check. Pilot performance and subjective rating of simulator fidelity was relatively insensitive to the motion condition, despite large differences in the amplitude of motion provided. This lack of sensitivity may be explained by means of the vestibular models, which predict little difference in the modeled motion sensations of the pilots when different motion conditions are imposed.

  11. The Cosmic Origins Spectrograph Pre-flight Aperture Model and SIAF.dat File

    Science.gov (United States)

    Lallo, Matthew

    2008-09-01

    This Instrument Science Report documents the derivation of the final pre-flight COS aperture locations and geometries. It also describes the spreadsheet model and SIAF.dat file containing them. These data will provide the operational pointing parameters for initial COS observations during Servicing Mission Orbital Verification 4 (SMOV4). A future report will describe the onorbit calibration results for COS and subsequent revisions to the spreadsheet model.

  12. Flight dynamics and control modelling of damaged asymmetric aircraft

    Science.gov (United States)

    Ogunwa, T. T.; Abdullah, E. J.

    2016-10-01

    This research investigates the use of a Linear Quadratic Regulator (LQR) controller to assist commercial Boeing 747-200 aircraft regains its stability in the event of damage. Damages cause an aircraft to become asymmetric and in the case of damage to a fraction (33%) of its left wing or complete loss of its vertical stabilizer, the loss of stability may lead to a fatal crash. In this study, aircraft models for the two damage scenarios previously mentioned are constructed using stability derivatives. LQR controller is used as a direct adaptive control design technique for the observable and controllable system. Dynamic stability analysis is conducted in the time domain for all systems in this study.

  13. A Comparison of the NAVTOLAND (Navy Vertical Takeoff and Landing) SH-2F Helicopter Model with the Requirements of MIL-H-8501A and with Flight Data.

    Science.gov (United States)

    2014-09-26

    Response in Hover VS. Flight Test Data and M I L-H-8501A Requirements Flight MIL-H-8501A Model Test VFR IFR Pitch attitude in + 3.60 +40 - 1.870 3.00...response than is indicated by the model. Both the model and the flight test results exceed IFR specification re- quirements. Model pitch response for

  14. The Integrated Medical Model: A Risk Assessment and Decision Support Tool for Human Space Flight Missions

    Science.gov (United States)

    Kerstman, Eric L.; Minard, Charles; FreiredeCarvalho, Mary H.; Walton, Marlei E.; Myers, Jerry G., Jr.; Saile, Lynn G.; Lopez, Vilma; Butler, Douglas J.; Johnson-Throop, Kathy A.

    2011-01-01

    This slide presentation reviews the Integrated Medical Model (IMM) and its use as a risk assessment and decision support tool for human space flight missions. The IMM is an integrated, quantified, evidence-based decision support tool useful to NASA crew health and mission planners. It is intended to assist in optimizing crew health, safety and mission success within the constraints of the space flight environment for in-flight operations. It uses ISS data to assist in planning for the Exploration Program and it is not intended to assist in post flight research. The IMM was used to update Probability Risk Assessment (PRA) for the purpose of updating forecasts for the conditions requiring evacuation (EVAC) or Loss of Crew Life (LOC) for the ISS. The IMM validation approach includes comparison with actual events and involves both qualitative and quantitaive approaches. The results of these comparisons are reviewed. Another use of the IMM is to optimize the medical kits taking into consideration the specific mission and the crew profile. An example of the use of the IMM to optimize the medical kits is reviewed.

  15. The Integrated Medical Model: A Risk Assessment and Decision Support Tool for Space Flight Medical Systems

    Science.gov (United States)

    Kerstman, Eric; Minard, Charles; Saile, Lynn; deCarvalho, Mary Freire; Myers, Jerry; Walton, Marlei; Butler, Douglas; Iyengar, Sriram; Johnson-Throop, Kathy; Baumann, David

    2009-01-01

    The Integrated Medical Model (IMM) is a decision support tool that is useful to mission planners and medical system designers in assessing risks and designing medical systems for space flight missions. The IMM provides an evidence based approach for optimizing medical resources and minimizing risks within space flight operational constraints. The mathematical relationships among mission and crew profiles, medical condition incidence data, in-flight medical resources, potential crew functional impairments, and clinical end-states are established to determine probable mission outcomes. Stochastic computational methods are used to forecast probability distributions of crew health and medical resource utilization, as well as estimates of medical evacuation and loss of crew life. The IMM has been used in support of the International Space Station (ISS) medical kit redesign, the medical component of the ISS Probabilistic Risk Assessment, and the development of the Constellation Medical Conditions List. The IMM also will be used to refine medical requirements for the Constellation program. The IMM outputs for ISS and Constellation design reference missions will be presented to demonstrate the potential of the IMM in assessing risks, planning missions, and designing medical systems. The implementation of the IMM verification and validation plan will be reviewed. Additional planned capabilities of the IMM, including optimization techniques and the inclusion of a mission timeline, will be discussed. Given the space flight constraints of mass, volume, and crew medical training, the IMM is a valuable risk assessment and decision support tool for medical system design and mission planning.

  16. The Integrated Medical Model: A Probabilistic Simulation Model Predicting In-Flight Medical Risks

    Science.gov (United States)

    Keenan, Alexandra; Young, Millennia; Saile, Lynn; Boley, Lynn; Walton, Marlei; Kerstman, Eric; Shah, Ronak; Goodenow, Debra A.; Myers, Jerry G., Jr.

    2015-01-01

    The Integrated Medical Model (IMM) is a probabilistic model that uses simulation to predict mission medical risk. Given a specific mission and crew scenario, medical events are simulated using Monte Carlo methodology to provide estimates of resource utilization, probability of evacuation, probability of loss of crew, and the amount of mission time lost due to illness. Mission and crew scenarios are defined by mission length, extravehicular activity (EVA) schedule, and crew characteristics including: sex, coronary artery calcium score, contacts, dental crowns, history of abdominal surgery, and EVA eligibility. The Integrated Medical Evidence Database (iMED) houses the model inputs for one hundred medical conditions using in-flight, analog, and terrestrial medical data. Inputs include incidence, event durations, resource utilization, and crew functional impairment. Severity of conditions is addressed by defining statistical distributions on the dichotomized best and worst-case scenarios for each condition. The outcome distributions for conditions are bounded by the treatment extremes of the fully treated scenario in which all required resources are available and the untreated scenario in which no required resources are available. Upon occurrence of a simulated medical event, treatment availability is assessed, and outcomes are generated depending on the status of the affected crewmember at the time of onset, including any pre-existing functional impairments or ongoing treatment of concurrent conditions. The main IMM outcomes, including probability of evacuation and loss of crew life, time lost due to medical events, and resource utilization, are useful in informing mission planning decisions. To date, the IMM has been used to assess mission-specific risks with and without certain crewmember characteristics, to determine the impact of eliminating certain resources from the mission medical kit, and to design medical kits that maximally benefit crew health while meeting

  17. The Integrated Medical Model: A Probabilistic Simulation Model for Predicting In-Flight Medical Risks

    Science.gov (United States)

    Keenan, Alexandra; Young, Millennia; Saile, Lynn; Boley, Lynn; Walton, Marlei; Kerstman, Eric; Shah, Ronak; Goodenow, Debra A.; Myers, Jerry G.

    2015-01-01

    The Integrated Medical Model (IMM) is a probabilistic model that uses simulation to predict mission medical risk. Given a specific mission and crew scenario, medical events are simulated using Monte Carlo methodology to provide estimates of resource utilization, probability of evacuation, probability of loss of crew, and the amount of mission time lost due to illness. Mission and crew scenarios are defined by mission length, extravehicular activity (EVA) schedule, and crew characteristics including: sex, coronary artery calcium score, contacts, dental crowns, history of abdominal surgery, and EVA eligibility. The Integrated Medical Evidence Database (iMED) houses the model inputs for one hundred medical conditions using in-flight, analog, and terrestrial medical data. Inputs include incidence, event durations, resource utilization, and crew functional impairment. Severity of conditions is addressed by defining statistical distributions on the dichotomized best and worst-case scenarios for each condition. The outcome distributions for conditions are bounded by the treatment extremes of the fully treated scenario in which all required resources are available and the untreated scenario in which no required resources are available. Upon occurrence of a simulated medical event, treatment availability is assessed, and outcomes are generated depending on the status of the affected crewmember at the time of onset, including any pre-existing functional impairments or ongoing treatment of concurrent conditions. The main IMM outcomes, including probability of evacuation and loss of crew life, time lost due to medical events, and resource utilization, are useful in informing mission planning decisions. To date, the IMM has been used to assess mission-specific risks with and without certain crewmember characteristics, to determine the impact of eliminating certain resources from the mission medical kit, and to design medical kits that maximally benefit crew health while meeting

  18. Modeling Pilot Behavior for Assessing Integrated Alert and Notification Systems on Flight Decks

    Science.gov (United States)

    Cover, Mathew; Schnell, Thomas

    2010-01-01

    Numerous new flight deck configurations for caution, warning, and alerts can be conceived; yet testing them with human-in-the-Ioop experiments to evaluate each one would not be practical. New sensors, instruments, and displays are being put into cockpits every day and this is particularly true as we enter the dawn of the Next Generation Air Transportation System (NextGen). By modeling pilot behavior in a computer simulation, an unlimited number of unique caution, warning, and alert configurations can be evaluated 24/7 by a computer. These computer simulations can then identify the most promising candidate formats to further evaluate in higher fidelity, but more costly, Human-in-the-Ioop (HITL) simulations. Evaluations using batch simulations with human performance models saves time, money, and enables a broader consideration of possible caution, warning, and alerting configurations for future flight decks.

  19. Analysis, Modeling and Dynamic Optimization of 3D Time-of-Flight Imaging Systems

    OpenAIRE

    Schmidt, Mirko

    2011-01-01

    The present thesis is concerned with the optimization of 3D Time-of-Flight (ToF) imaging systems. These novel cameras determine range images by actively illuminating a scene and measuring the time until the backscattered light is detected. Depth maps are constructed from multiple raw images. Usually two of such raw images are acquired simultaneously using special correlating sensors. This thesis covers four main contributions: A physical sensor model is presented which enables the analysis a...

  20. Flight Experiments on Swept-Wing Roughness Receptivity: Validation Data for Modeling and Computations

    Science.gov (United States)

    2010-09-22

    Photodetector which is cooled to 70 K with an onboard Stirling motor cooler . The camera has a sensitivity of 0.02 C at a temperature of 30 C...a Kemo VBF44 bandpass filter12. A new coordinate system was developed for studying this unconventional, vertically-mounted airfoil. The aircraft...psid, 16-bit, Pressure Systems scanner. The scanner was imbedded inside the model to reduce pressure lag time within the tubing. For all Cp flights

  1. Integrated Flight Mechanic and Aeroelastic Modelling and Control of a Flexible Aircraft Considering Multidimensional Gust Input

    Science.gov (United States)

    2000-05-01

    INTEGRATED FLIGHT MECHANIC AND AEROELASTIC MODELLING AND CONTROL OF A FLEXIBLE AIRCRAFT CONSIDERING MULTIDIMENSIONAL GUST INPUT Patrick Teufel, Martin Hanel...the lateral separation distance have been developed by ’ = matrix of two dimensional spectrum function Eichenbaum 4 and are described by Bessel...Journal of Aircraft, Vol. 30, No. 5, Sept.-Oct. 1993 Relations to Risk Sensitivity, System & Control Letters 11, [4] Eichenbaum F.D., Evaluation of 3D

  2. Simulacioni model sistema za upravljanje letom protivbrodske rakete / Model for simulating the flight control system of a antiship missile

    Directory of Open Access Journals (Sweden)

    Nebojša N. Gaćeša

    2007-04-01

    Full Text Available U radu je analiziran program za simulaciju sistema za upravljanje letom protivbrodske rakete sa radarskom glavom za samonavođenje. Analiziran je matematički model rakete, model autopilota i model cilja. Ovakvim pristupom dobijen je rezultat koji omogućava uspostavljanje realnijeg procesa praćenja leta konkretne protivbrodske rakete, budući da upravljanje letom rakete na celoj trajektoriji ima znatne prednosti u odnosu na nevođene projektile, pre svega zbog mogućnosti gađanja pokretnih ciljeva. Simulacioni model upravljanja letom rakete pruža mogućnosti za dalje proučavanje ove klase raketa. / The paper analyzes a program for simulating the flight control of an antiship missile with the radar seeker. The paper analyzes a mathematic missile model an autopilot model and a target model. Thus obtained results enable a more realistic process of flight tracking of a particular antiship missile as the missile guidance along the whole trajectory provides many advantages over unguided projectiles, primarily because of the possibility to fire at moving targets. The flight control simulation model enables further study of this missile class.

  3. Aerodynamic Interactions Between Wing and Body of a Model Insect in Forward Flight and Maneuvers

    Institute of Scientific and Technical Information of China (English)

    Bin Liang; Mao Sun

    2013-01-01

    The aerodynamic interactions between the body and the wings of a model insect in forward flight and maneuvers are studied using the method of numerically solving the Navier-Stokes equations over moving overset grids.Three cases are considered,including a complete insect,wing pair only and body only.By comparing the results of these cases,the interaction effect between the body and the wing pair can be identified.The changes in the force and moment coefficients of the wing pair due to the presence of the body are less than 4.5% of the mean vertical force coefficient of the model insect; the changes in the aerodynamic force coefficients of the body due to the presence of the wings are less than 5.0% of the mean vertical force coefficient of the model insect.The results of this paper indicate that in studying the aerodynamics and flight dynamics of a flapping insect in forward flight or maneuver,separately computing (or measuring) the aerodynamic forces and moments on the wing pair and on the body could be a good approximation.

  4. Formulation and validation of high-order linearized models of helicopter flight mechanics

    Science.gov (United States)

    Kim, Frederick D.; Celi, Roberto; Tischler, Mark B.

    1990-01-01

    A high-order linearized model of helicopter flight dynamics is extracted from a nonlinear time domain simulation. The model has 29 states that describe the fuselage rigid body degrees of freedom, the flap and lag dynamics in a nonrotating coordinate system, the inflow dynamics, the delayed entry of the horizontal tail into the main rotor wake, and, approximately, the blade torsion dynamics. The nonlinear simulation is obtained by extensively modifying the GENHEL computer program. The results indicate that the agreement between the linearized and the nonlinear model is good for small perturbations, and deteriorates for large amplitude maneuvers.

  5. Polychronous Interpretation of Synoptic, a Domain Specific Modeling Language for Embedded Flight-Software

    Directory of Open Access Journals (Sweden)

    Loïc Besnard

    2010-03-01

    Full Text Available The SPaCIFY project, which aims at bringing advances in MDE to the satellite flight software industry, advocates a top-down approach built on a domain-specific modeling language named Synoptic. In line with previous approaches to real-time modeling such as Statecharts and Simulink, Synoptic features hierarchical decomposition of application and control modules in synchronous block diagrams and state machines. Its semantics is described in the polychronous model of computation, which is that of the synchronous language SIGNAL.

  6. 76 FR 31456 - Special Conditions: Gulfstream Model GVI Airplane; Electronic Flight Control System: Control...

    Science.gov (United States)

    2011-06-01

    ...; Electronic Flight Control System: Control Surface Position Awareness AGENCY: Federal Aviation Administration... design features include an electronic flight control system. The applicable airworthiness regulations do... an electronic flight control system and no direct coupling from the cockpit controller to the...

  7. Dynamical modeling of collective behavior from pigeon flight data: flock cohesion and dispersion.

    Science.gov (United States)

    Dieck Kattas, Graciano; Xu, Xiao-Ke; Small, Michael

    2012-01-01

    Several models of flocking have been promoted based on simulations with qualitatively naturalistic behavior. In this paper we provide the first direct application of computational modeling methods to infer flocking behavior from experimental field data. We show that this approach is able to infer general rules for interaction, or lack of interaction, among members of a flock or, more generally, any community. Using experimental field measurements of homing pigeons in flight we demonstrate the existence of a basic distance dependent attraction/repulsion relationship and show that this rule is sufficient to explain collective behavior observed in nature. Positional data of individuals over time are used as input data to a computational algorithm capable of building complex nonlinear functions that can represent the system behavior. Topological nearest neighbor interactions are considered to characterize the components within this model. The efficacy of this method is demonstrated with simulated noisy data generated from the classical (two dimensional) Vicsek model. When applied to experimental data from homing pigeon flights we show that the more complex three dimensional models are capable of simulating trajectories, as well as exhibiting realistic collective dynamics. The simulations of the reconstructed models are used to extract properties of the collective behavior in pigeons, and how it is affected by changing the initial conditions of the system. Our results demonstrate that this approach may be applied to construct models capable of simulating trajectories and collective dynamics using experimental field measurements of herd movement. From these models, the behavior of the individual agents (animals) may be inferred.

  8. Computational Model of Human and System Dynamics in Free Flight: Studies in Distributed Control Technologies

    Science.gov (United States)

    Corker, Kevin M.; Pisanich, Gregory; Lebacqz, J. Victor (Technical Monitor)

    1998-01-01

    This paper presents a set of studies in full mission simulation and the development of a predictive computational model of human performance in control of complex airspace operations. NASA and the FAA have initiated programs of research and development to provide flight crew, airline operations and air traffic managers with automation aids to increase capacity in en route and terminal area to support the goals of safe, flexible, predictable and efficient operations. In support of these developments, we present a computational model to aid design that includes representation of multiple cognitive agents (both human operators and intelligent aiding systems). The demands of air traffic management require representation of many intelligent agents sharing world-models, coordinating action/intention, and scheduling goals and actions in a potentially unpredictable world of operations. The operator-model structure includes attention functions, action priority, and situation assessment. The cognitive model has been expanded to include working memory operations including retrieval from long-term store, and interference. The operator's activity structures have been developed to provide for anticipation (knowledge of the intention and action of remote operators), and to respond to failures of the system and other operators in the system in situation-specific paradigms. System stability and operator actions can be predicted by using the model. The model's predictive accuracy was verified using the full-mission simulation data of commercial flight deck operations with advanced air traffic management techniques.

  9. Robust Near-Hovering Flight Controller for Model-Scale Helicopters Via Parametric Approach

    Institute of Scientific and Technical Information of China (English)

    Zhigang Zhou; Yongan Zhang∗

    2015-01-01

    This paper aims to provide a parametric design for robust flight controller of the model⁃scale helicopter. The main contributions lie in two aspects. Firstly, under near⁃hovering condition, a procedure is presented for simplification of the highly nonlinear and under⁃actuated model of the model⁃scale helicopter. This nonlinear system is linearized around the trim values of the chosen flight mode, followed by decomposing this high⁃order linear model into three lower⁃order subsystems according to the coupling properties among channels. After decomposition, the three subsystems are obtained which include the coupling subsystem between the roll ( pitch) motion and the lateral ( longitudinal) motion, the subsystem of the yaw motion and the subsystem of the vertical motion. Secondly, by using eigenstructure assignment, the problem of flight controller design can be converted into solving two optimization problems and the linear robust controllers of these subsystems are designed through solving these optimization problems. Besides, this paper contrasts and analyzed the performances of the LQR controller and the parametric controller. The results demonstrate the effectiveness and the robustness against the parametric perturbations of the parametric controller.

  10. Development of a Dynamically Scaled Generic Transport Model Testbed for Flight Research Experiments

    Science.gov (United States)

    Jordan, Thomas; Langford, William; Belcastro, Christine; Foster, John; Shah, Gautam; Howland, Gregory; Kidd, Reggie

    2004-01-01

    This paper details the design and development of the Airborne Subscale Transport Aircraft Research (AirSTAR) test-bed at NASA Langley Research Center (LaRC). The aircraft is a 5.5% dynamically scaled, remotely piloted, twin-turbine, swept wing, Generic Transport Model (GTM) which will be used to provide an experimental flight test capability for research experiments pertaining to dynamics modeling and control beyond the normal flight envelope. The unique design challenges arising from the dimensional, weight, dynamic (inertial), and actuator scaling requirements necessitated by the research community are described along with the specific telemetry and control issues associated with a remotely piloted subscale research aircraft. Development of the necessary operational infrastructure, including operational and safety procedures, test site identification, and research pilots is also discussed. The GTM is a unique vehicle that provides significant research capacity due to its scaling, data gathering, and control characteristics. By combining data from this testbed with full-scale flight and accident data, wind tunnel data, and simulation results, NASA will advance and validate control upset prevention and recovery technologies for transport aircraft, thereby reducing vehicle loss-of-control accidents resulting from adverse and upset conditions.

  11. A coupled kinematics-energetics model for predicting energy efficient flapping flight.

    Science.gov (United States)

    Salehipour, Hesam; Willis, David J

    2013-02-07

    A new computational model based on an optimal power, wake-only aerodynamics method is presented to predict the interdependency of energetics and kinematics in bird and bat flight. The model is divided into offline, intermediate and online modules. In the offline module, a four-dimensional design space sweep is performed (lift, thrust, flapping amplitude and flapping frequency). In the intermediate stage, the physical characteristics of the animal are introduced (wing span, mass, wing area, aspect ratio, etc.), and a series of amplitude-frequency response surfaces are constructed for all viable flight speeds. In the online component, the amplitude-frequency response surfaces are mined for the specific flapping motions being considered. The method is applied to several biological examples including a medium sized fruit bat (Cynopterus brachyotis), and two birds: a thrush nightingale (Luscinia luscinia) and a budgerigar (Melopsittacus undulatus). For each of these animals, the power and kinematics predictions are compared with available experimental data. These examples demonstrate that this new method can reasonably predict animal flight energetics and kinematics.

  12. Three-dimensional numerical simulation of a bird model in unsteady flight

    Science.gov (United States)

    Lin-Lin, Zhu; Hui, Guan; Chui-Jie, Wu

    2016-07-01

    In this paper, a type of numerical simulation of a three-dimensional (3D) bionic bird with flapping wings in a viscous flow is studied. The model is a self-propelled flying bird capable of free rotation and translation whose flying motion follows the laws of conservation of momentum and angular momentum. The bird is propelled and lifted through flapping and rotating wings and most of thrust force and lift force are exerted on both wings. Both the vortex structures and the flight characteristics are also presented. The relationship between both wings' movement and the vortex structures as well as that between both wings' movement and flight characteristics are also analyzed in this paper. The study uses a 3D computational fluid dynamics package that includes the combined immersed boundary method, volume of fluid method, adaptive multigrid finite volume method, and control strategy for swimming and flying.

  13. A simple hydrodynamic model of a laminar free-surface jet in horizontal or vertical flight

    Science.gov (United States)

    Haustein, Herman D.; Harnik, Ron S.; Rohlfs, Wilko

    2017-08-01

    A useable model for laminar free-surface jet evolution during flight, for both horizontal and vertical jets, is developed through joint analytical, experimental, and simulation methods. The jet's impingement centerline velocity, recently shown to dictate stagnation zone heat transfer, encompasses the entire flow history: from pipe-flow velocity profile development to profile relaxation and jet contraction during flight. While pipe-flow is well-known, an alternative analytic solution is presented for the centerline velocity's viscous-driven decay. Jet-contraction is subject to influences of surface tension (We), pipe-flow profile development, in-flight viscous dissipation (Re), and gravity (Nj = Re/Fr). The effects of surface tension and emergence momentum flux (jet thrust) are incorporated analytically through a global momentum balance. Though emergence momentum is related to pipe flow development, and empirically linked to nominal pipe flow-length, it can be modified to incorporate low-Re downstream dissipation as well. Jet contraction's gravity dependence is extended beyond existing uniform-velocity theory to cases of partially and fully developed profiles. The final jet-evolution model relies on three empirical parameters and compares well to present and previous experiments and simulations. Hence, micro-jet flight experiments were conducted to fill-in gaps in the literature: jet contraction under mild gravity-effects, and intermediate Reynolds and Weber numbers (Nj = 5-8, Re = 350-520, We = 2.8-6.2). Furthermore, two-phase direct numerical simulations provided insight beyond the experimental range: Re = 200-1800, short pipes (Z = L/d . Re ≥ 0.01), variable nozzle wettability, and cases of no surface tension and/or gravity.

  14. Aeroelastic Modeling of X-56A Stiff-Wing Configuration Flight Test Data

    Science.gov (United States)

    Grauer, Jared A.; Boucher, Matthew J.

    2017-01-01

    Aeroelastic stability and control derivatives for the X-56A Multi-Utility Technology Testbed (MUTT), in the stiff-wing configuration, were estimated from flight test data using the output-error method. Practical aspects of the analysis are discussed. The orthogonal phase-optimized multisine inputs provided excellent data information for aeroelastic modeling. Consistent parameter estimates were determined using output error in both the frequency and time domains. The frequency domain analysis converged faster and was less sensitive to starting values for the model parameters, which was useful for determining the aeroelastic model structure and obtaining starting values for the time domain analysis. Including a modal description of the structure from a finite element model reduced the complexity of the estimation problem and improved the modeling results. Effects of reducing the model order on the short period stability and control derivatives were investigated.

  15. Population dynamics and flight phenology model of codling moth differ between commercial and abandoned apple orchard ecosystems

    Directory of Open Access Journals (Sweden)

    Neelendra K Joshi

    2016-09-01

    Full Text Available Apple orchard management practices may affect development and phenology of arthropod pests, such as the codling moth (CM, Cydia pomonella (L. (Lepidoptera: Tortricidae, which is a serious internal fruit-feeding pest of apples worldwide. Estimating population dynamics and accurately predicting the timing of CM development and phenology events (for instance, adult flight and egg-hatch allows growers to understand and control local populations of CM. Studies were conducted to compare the CM flight phenology in commercial and abandoned apple orchard ecosystems using a logistic function model based on degree-days accumulation. The flight models for these orchards were derived from the cumulative percent moth capture using two types of commercially available CM lure baited traps. Models from both types of orchards were also compared to another model known as PETE (prediction extension timing estimator that was developed in 1970s to predict life cycle events for many fruit pests including CM across different fruit growing regions of the United States. We found that the flight phenology of CM was significantly different in commercial and abandoned orchards. CM male flight patterns for first and second generations as predicted by the constrained and unconstrained PCM (Pennsylvania Codling Moth models in commercial and abandoned orchards were different than the flight patterns predicted by the currently used CM model (i.e.,1970’s model. In commercial orchards, during the first and second generations, the PCM unconstrained model predicted delays in moth emergence compared to current model. In addition, the flight patterns of females were different between commercial and abandoned orchards. Such differences in CM flight phenology between commercial and abandoned orchard ecosystems suggest potential impact of orchard environment and crop management practices on CM biology.

  16. Population Dynamics and Flight Phenology Model of Codling Moth Differ between Commercial and Abandoned Apple Orchard Ecosystems.

    Science.gov (United States)

    Joshi, Neelendra K; Rajotte, Edwin G; Naithani, Kusum J; Krawczyk, Greg; Hull, Larry A

    2016-01-01

    Apple orchard management practices may affect development and phenology of arthropod pests, such as the codling moth (CM), Cydia pomonella (L.) (Lepidoptera: Tortricidae), which is a serious internal fruit-feeding pest of apples worldwide. Estimating population dynamics and accurately predicting the timing of CM development and phenology events (for instance, adult flight, and egg-hatch) allows growers to understand and control local populations of CM. Studies were conducted to compare the CM flight phenology in commercial and abandoned apple orchard ecosystems using a logistic function model based on degree-days accumulation. The flight models for these orchards were derived from the cumulative percent moth capture using two types of commercially available CM lure baited traps. Models from both types of orchards were also compared to another model known as PETE (prediction extension timing estimator) that was developed in 1970s to predict life cycle events for many fruit pests including CM across different fruit growing regions of the United States. We found that the flight phenology of CM was significantly different in commercial and abandoned orchards. CM male flight patterns for first and second generations as predicted by the constrained and unconstrained PCM (Pennsylvania Codling Moth) models in commercial and abandoned orchards were different than the flight patterns predicted by the currently used CM model (i.e., PETE model). In commercial orchards, during the first and second generations, the PCM unconstrained model predicted delays in moth emergence compared to current model. In addition, the flight patterns of females were different between commercial and abandoned orchards. Such differences in CM flight phenology between commercial and abandoned orchard ecosystems suggest potential impact of orchard environment and crop management practices on CM biology.

  17. Population Dynamics and Flight Phenology Model of Codling Moth Differ between Commercial and Abandoned Apple Orchard Ecosystems

    Science.gov (United States)

    Joshi, Neelendra K.; Rajotte, Edwin G.; Naithani, Kusum J.; Krawczyk, Greg; Hull, Larry A.

    2016-01-01

    Apple orchard management practices may affect development and phenology of arthropod pests, such as the codling moth (CM), Cydia pomonella (L.) (Lepidoptera: Tortricidae), which is a serious internal fruit-feeding pest of apples worldwide. Estimating population dynamics and accurately predicting the timing of CM development and phenology events (for instance, adult flight, and egg-hatch) allows growers to understand and control local populations of CM. Studies were conducted to compare the CM flight phenology in commercial and abandoned apple orchard ecosystems using a logistic function model based on degree-days accumulation. The flight models for these orchards were derived from the cumulative percent moth capture using two types of commercially available CM lure baited traps. Models from both types of orchards were also compared to another model known as PETE (prediction extension timing estimator) that was developed in 1970s to predict life cycle events for many fruit pests including CM across different fruit growing regions of the United States. We found that the flight phenology of CM was significantly different in commercial and abandoned orchards. CM male flight patterns for first and second generations as predicted by the constrained and unconstrained PCM (Pennsylvania Codling Moth) models in commercial and abandoned orchards were different than the flight patterns predicted by the currently used CM model (i.e., PETE model). In commercial orchards, during the first and second generations, the PCM unconstrained model predicted delays in moth emergence compared to current model. In addition, the flight patterns of females were different between commercial and abandoned orchards. Such differences in CM flight phenology between commercial and abandoned orchard ecosystems suggest potential impact of orchard environment and crop management practices on CM biology. PMID:27713702

  18. Ornithopter flight stabilization

    Science.gov (United States)

    Dietl, John M.; Garcia, Ephrahim

    2007-04-01

    The quasi-steady aerodynamics model and the vehicle dynamics model of ornithopter flight are explained, and numerical methods are described to capture limit cycle behavior in ornithopter flight. The Floquet method is used to determine stability in forward flight, and a linear discrete-time state-space model is developed. This is used to calculate stabilizing and disturbance-rejecting controllers.

  19. Comparison of In-Flight Measured and Computed Aeroelastic Damping: Modal Identification Procedures and Modeling Approaches

    Directory of Open Access Journals (Sweden)

    Roberto da Cunha Follador

    2016-04-01

    Full Text Available The Operational Modal Analysis technique is a methodology very often applied for the identification of dynamic systems when the input signal is unknown. The applied methodology is based on a technique to estimate the Frequency Response Functions and extract the modal parameters using only the structural dynamic response data, without assuming the knowledge of the excitation forces. Such approach is an adequate way for measuring the aircraft aeroelastic response due to random input, like atmospheric turbulence. The in-flight structural response has been measured by accelerometers distributed along the aircraft wings, fuselage and empennages. The Enhanced Frequency Domain Decomposition technique was chosen to identify the airframe dynamic parameters. This technique is based on the hypothesis that the system is randomly excited with a broadband spectrum with almost constant power spectral density. The system identification procedure is based on the Single Value Decomposition of the power spectral densities of system output signals, estimated by the usual Fast Fourier Transform method. This procedure has been applied to different flight conditions to evaluate the modal parameters and the aeroelastic stability trends of the airframe under investigation. The experimental results obtained by this methodology were compared with the predicted results supplied by aeroelastic numerical models in order to check the consistency of the proposed output-only methodology. The objective of this paper is to compare in-flight measured aeroelastic damping against the corresponding parameters computed from numerical aeroelastic models. Different aerodynamic modeling approaches should be investigated such as the use of source panel body models, cruciform and flat plate projection. As a result of this investigation it is expected the choice of the better aeroelastic modeling and Operational Modal Analysis techniques to be included in a standard aeroelastic

  20. Comparison of model predictions for coherence length to in-flight measurements at cruise conditions

    Science.gov (United States)

    Haxter, Stefan; Spehr, Carsten

    2017-03-01

    In this paper, we will focus on coherence lengths of pressure fluctuations underneath a turbulent boundary layer on an actual aircraft measured during a flight test. Coherence lengths of pressure fluctuations have already been measured in the past and various models have been set up in order to predict the values. However, most of the underlying data were measured at Mach numbers and pressures different from our region of interest and it is not known if the models are applicable. In some of the investigations also unknown alignment procedures between array and flow were used and it will be shown that this can have a considerable influence on the result. We have performed flight tests at cruising speed and altitude in which we took due account of this alignment by means of an array processing technique which is capable of determining the flow direction for each frequency bin under consideration. In this paper one of the data points will be evaluated and compared to the prediction models. From the differences and subsequently from the adopted run conditions for the measurement of the data of the models, several conclusions are drawn concerning scaling effects and importance of alignment. Also, two of the prediction models are adjusted to our measurements.

  1. Primary safe criterion of earth-brushing flight for flying vehicle over digital surface model

    Institute of Scientific and Technical Information of China (English)

    赵敏; 林行刚; 赵乃国

    2004-01-01

    In modem terrain-following guidance it is an important index for flight vehicle to cruise about safely and normally. On the basis of a constructing method of digital surface model (DSM), the definition, classification and scale analysis of an isolated obstacle threatening flight safety of terrain-following guidance are made. When the interval of verticaland cross-sections on DSM is 12.5 m, the proportion of isolated obstacles to the data amount of DSM model to be loaded is optimal. The main factors influencing the lowest flying height in terrain-following guidance are analyzed, and a primary safe criterion of the lowest flying height over DSM model is proposed. According to their test errors, the lowest flying height over 1:10 000 DSM model can reach 40.5 m~45.0 m in terrain-following guidance. It is shown from the simulation results of a typical urban district that the proposed models and methods are reasonable and feasible.

  2. 75 FR 77569 - Special Conditions: Gulfstream Model GVI Airplane; Electronic Flight Control System Mode...

    Science.gov (United States)

    2010-12-13

    ...; Electronic Flight Control System Mode Annunciation AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... design features include an electronic flight control system. The applicable airworthiness regulations do... system. This system provides an electronic interface between the pilot's flight controls and ] the flight...

  3. Low Density Supersonic Decelerator (LDSD) Supersonic Flight Dynamics Test (SFDT) Plume Induced Environment Modelling

    Science.gov (United States)

    Mobley, B. L.; Smith, S. D.; Van Norman, J. W.; Muppidi, S.; Clark, I

    2016-01-01

    Provide plume induced heating (radiation & convection) predictions in support of the LDSD thermal design (pre-flight SFDT-1) Predict plume induced aerodynamics in support of flight dynamics, to achieve targeted freestream conditions to test supersonic deceleration technologies (post-flight SFDT-1, pre-flight SFDT-2)

  4. Gamma ray Large Area Space Telescope (GLAST) Balloon Flight Engineering Model Overview

    CERN Document Server

    Thompson, D J; Williams, S; Grove, J E; Mizuno, T; Sadrozinski, H F W

    2002-01-01

    The Gamma Ray Large Area Space Telescope (GLAST) Large Area Telescope (LAT) is a pair-production high-energy (>20 MeV) gamma-ray telescope being built by an international partnership of astrophysicists and particle physicists for a satellite launch in 2006, designed to study a wide variety of high-energy astrophysical phenomena. As part of the development effort, the collaboration has built a Balloon Flight Engineering Model (BFEM) for flight on a high-altitude scientific balloon. The BFEM is approximately the size of one of the 16 GLAST-LAT towers and contains all the components of the full instrument: plastic scintillator anticoincidence system (ACD), high-Z foil/Si strip pair-conversion tracker (TKR), CsI hodoscopic calorimeter (CAL), triggering and data acquisition electronics (DAQ), commanding system, power distribution, telemetry, real-time data display, and ground data processing system. The principal goal of the balloon flight was to demonstrate the performance of this instrument configuration under c...

  5. Lateral dynamic flight stability of a model hoverfly in normal and inclined stroke-plane hovering.

    Science.gov (United States)

    Xu, Na; Sun, Mao

    2014-09-01

    Many insects hover with their wings beating in a horizontal plane ('normal hovering'), while some insects, e.g., hoverflies and dragonflies, hover with inclined stroke-planes. Here, we investigate the lateral dynamic flight stability of a hovering model hoverfly. The aerodynamic derivatives are computed using the method of computational fluid dynamics, and the equations of motion are solved by the techniques of eigenvalue and eigenvector analysis. The following is shown: The flight of the insect is unstable at normal hovering (stroke-plane angle equals 0) and the instability becomes weaker as the stroke-plane angle increases; the flight becomes stable at a relatively large stroke-plane angle (larger than about 24°). As previously shown, the instability at normal hovering is due to a positive roll-moment/side-velocity derivative produced by the 'changing-LEV-axial-velocity' effect. When the stroke-plane angle increases, the wings bend toward the back of the body, and the 'changing-LEV-axial-velocity' effect decreases; in addition, another effect, called the 'changing-relative-velocity' effect (the 'lateral wind', which is due to the side motion of the insect, changes the relative velocity of its wings), becomes increasingly stronger. This causes the roll-moment/side-velocity derivative to first decrease and then become negative, resulting in the above change in stability as a function of the stroke-plane angle.

  6. Honeybees as a model for the study of visually guided flight, navigation, and biologically inspired robotics.

    Science.gov (United States)

    Srinivasan, Mandyam V

    2011-04-01

    Research over the past century has revealed the impressive capacities of the honeybee, Apis mellifera, in relation to visual perception, flight guidance, navigation, and learning and memory. These observations, coupled with the relative ease with which these creatures can be trained, and the relative simplicity of their nervous systems, have made honeybees an attractive model in which to pursue general principles of sensorimotor function in a variety of contexts, many of which pertain not just to honeybees, but several other animal species, including humans. This review begins by describing the principles of visual guidance that underlie perception of the world in three dimensions, obstacle avoidance, control of flight speed, and orchestrating smooth landings. We then consider how navigation over long distances is accomplished, with particular reference to how bees use information from the celestial compass to determine their flight bearing, and information from the movement of the environment in their eyes to gauge how far they have flown. Finally, we illustrate how some of the principles gleaned from these studies are now being used to design novel, biologically inspired algorithms for the guidance of unmanned aerial vehicles.

  7. Aerodynamic mechanism of forces generated by twisting model-wing in bat flapping flight

    Institute of Scientific and Technical Information of China (English)

    管子武; 余永亮

    2014-01-01

    The aerodynamic mechanism of the bat wing membrane along the lateral border of its body is studied. The twist-morphing that alters the angle of attack (AOA) along the span-wise direction is observed widely during bat flapping flight. An assumption is made that the linearly distributed AOA is along the span-wise direction. The plate with the aspect ratio of 3 is used to model a bat wing. A three-dimensional (3D) unsteady panel method is used to predict the aerodynamic forces generated by the flapping plate with leading edge separation. It is found that, relative to the rigid wing flapping, twisting motion can increase the averaged lift by as much as 25% and produce thrust instead of drag. Furthermore, the aerodynamic forces (lift/drag) generated by a twisting plate-wing are similar to those of a pitching rigid-wing, meaning that the twisting in bat flight has the same function as the supination/pronation motion in insect flight.

  8. Development of a thermal prediction model and flight data evaluation and comparison for the EOB experiment of the HELIOS solar probe

    Science.gov (United States)

    Kramp, K.; Ley, W.; Schmidt, H. P.

    1975-01-01

    A thermal model for the EOB experiment has been developed, adopted to test data, and used to predict flight temperatures. These predictions are compared to flight data covering the period from launch until the first black-out.

  9. Effect of wing mass in free flight by a butterfly-like 3D flapping wing-body model

    Science.gov (United States)

    Suzuki, Kosuke; Okada, Iori; Yoshino, Masato

    2016-11-01

    The effect of wing mass in free flight of a flapping wing is investigated by numerical simulations based on an immersed boundary-lattice Boltzmann method. We consider a butterfly-like 3D flapping wing-model consisting of two square wings with uniform mass density connected by a rod-shaped body. We simulate free flights of the wing-body model with various mass ratios of the wing to the whole of the model. As a result, it is found that the lift and thrust forces decrease as the mass ratio increases, since the body with a large mass ratio experiences large vertical and horizontal oscillations in one period and consequently the wing tip speed relatively decreases. In addition, we find the critical mass ratio between upward flight and downward flight for various Reynolds numbers. This work was supported by JSPS KAKENHI Grant Number JP16K18012.

  10. The Planck On-Flight Forecaster (POFF)

    CERN Document Server

    Massardi, M

    2009-01-01

    The Planck On-Fligh Forecaster (POFF) is a tool to predict when a position in the sky will be within a selected angular distance from any receiver direction of the Planck satellite according to its pre-programmed observational strategy. This tool has been developed in the framework of the Planck LFI Core Team activities, but it is now used by the whole collaboration. In this paper we will describe the tool and its applications to plan observations with other instruments of point sources which are expected to enhance the possibilities of scientific exploitation of the Planck satellite data, once they will be publicly available. Collecting simultaneous multi-frequency data, like those that can be planned with the POFF, will help, on one hand, to investigate variability of point sources and, on the other, to reconstruct point source spectral energy distributions on wide frequency ranges minimizing the effects due to source variability. POFF is a combination of IDL routines which combine the publicly available in...

  11. Orion Flight Test 1 Architecture: Observed Benefits of a Model Based Engineering Approach

    Science.gov (United States)

    Simpson, Kimberly A.; Sindiy, Oleg V.; McVittie, Thomas I.

    2012-01-01

    This paper details how a NASA-led team is using a model-based systems engineering approach to capture, analyze and communicate the end-to-end information system architecture supporting the first unmanned orbital flight of the Orion Multi-Purpose Crew Exploration Vehicle. Along with a brief overview of the approach and its products, the paper focuses on the observed program-level benefits, challenges, and lessons learned; all of which may be applied to improve system engineering tasks for characteristically similarly challenges

  12. Evaluation Model of Design for Operation and Architecture of Hierarchical Virtual Simulation for Flight Vehicle Design

    Institute of Scientific and Technical Information of China (English)

    LIU Hu; TIAN Yongliang; ZHANG Chaoying; YIN Jiao; SUN Yijie

    2012-01-01

    In order to take requirements for commercial operations or military missions into better consideration in new flight vehicle design,a tri-hierarchical task classification model of "design for operation" is proposed,which takes basic man-object interaction task,complex collaborative operation and large-scale joint operation into account.The corresponding general architecture of evaluation criteria is also depicted.Then a virtual simulation-based approach to implement the evaluations at three hierarchy levels is mainly analyzed with a detailed example,which validates the feasibility and effectiveness of evaluation architecture.Finally,extending the virtual simulation architecture from design to operation training is discussed.

  13. Dynamical modeling of collective behavior from pigeon flight data: flock cohesion and dispersion.

    Directory of Open Access Journals (Sweden)

    Graciano Dieck Kattas

    Full Text Available Several models of flocking have been promoted based on simulations with qualitatively naturalistic behavior. In this paper we provide the first direct application of computational modeling methods to infer flocking behavior from experimental field data. We show that this approach is able to infer general rules for interaction, or lack of interaction, among members of a flock or, more generally, any community. Using experimental field measurements of homing pigeons in flight we demonstrate the existence of a basic distance dependent attraction/repulsion relationship and show that this rule is sufficient to explain collective behavior observed in nature. Positional data of individuals over time are used as input data to a computational algorithm capable of building complex nonlinear functions that can represent the system behavior. Topological nearest neighbor interactions are considered to characterize the components within this model. The efficacy of this method is demonstrated with simulated noisy data generated from the classical (two dimensional Vicsek model. When applied to experimental data from homing pigeon flights we show that the more complex three dimensional models are capable of simulating trajectories, as well as exhibiting realistic collective dynamics. The simulations of the reconstructed models are used to extract properties of the collective behavior in pigeons, and how it is affected by changing the initial conditions of the system. Our results demonstrate that this approach may be applied to construct models capable of simulating trajectories and collective dynamics using experimental field measurements of herd movement. From these models, the behavior of the individual agents (animals may be inferred.

  14. Cardio-postural deconditioning: A model for post-flight orthostatic intolerance.

    Science.gov (United States)

    Blaber, Andrew P; Landrock, Clinton K; Souvestre, Philippe A

    2009-10-01

    Post-flight astronauts experience temporary but sometimes severe postural control dysfunction and decreased orthostatic tolerance. Research points to a possible link between cardiovascular and postural controls and orthostatic tolerance [Claydon,V.E., Hainsworth, R., 2006. Postural sway in patients with syncope and poor orthostatic tolerance. Heart 92, 1688-1689], for which a neurophysiological model has been presented [Souvestre, P.A., Blaber A.P., Landrock C.K., 2008. Space motion sickness: the sensory-motor controls and cardiovascular correlation. Acta Astronautica 63, 745-757]. To validate this model, young and elderly subjects (n=12) were compared with respect to postural mediolateral sway (ML sway) and blood pressure (BP) during quiet standing. Both groups had a peak in the low frequency region (0.03-0.07Hz) of cross-spectral power between ML sway and BP; however, only the young subjects had signal coherence greater than 0.5. Short-range Hurst coefficient from Stabilogram Dynamic Analysis was significantly lower for ML sway in young (0.694+/-0.068) compared to elderly subjects (0.812+/-0.10) (p=0.028). Young subjects were better able to command a closed-loop strategy of motor-control providing a more efficient postural control. Further application of this model with astronauts could lead to further understanding of post-flight orthostatic intolerance.

  15. Oscillation Susceptibility Analysis of the ADMIRE Aircraft along the Path of Longitudinal Flight Equilibriums in Two Different Mathematical Models

    Directory of Open Access Journals (Sweden)

    Achim Ionita

    2009-01-01

    Full Text Available The oscillation susceptibility of the ADMIRE aircraft along the path of longitudinal flight equilibriums is analyzed numerically in the general and in a simplified flight model. More precisely, the longitudinal flight equilibriums, the stability of these equilibriums, and the existence of bifurcations along the path of these equilibriums are researched in both models. Maneuvers and appropriate piloting tasks for the touch-down moment are simulated in both models. The computed results obtained in the models are compared in order to see if the movement concerning the landing phase computed in the simplified model is similar to that computed in the general model. The similarity we find is not a proof of the structural stability of the simplified system, what as far we know never been made, but can increase the confidence that the simplified system correctly describes the real phenomenon.

  16. Experimental Space Shuttle Orbiter Studies to Acquire Data for Code and Flight Heating Model Validation

    Science.gov (United States)

    Wadhams, T. P.; Holden, M. S.; MacLean, M. G.; Campbell, Charles

    2010-01-01

    In an experimental study to obtain detailed heating data over the Space Shuttle Orbiter, CUBRC has completed an extensive matrix of experiments using three distinct models and two unique hypervelocity wind tunnel facilities. This detailed data will be employed to assess heating augmentation due to boundary layer transition on the Orbiter wing leading edge and wind side acreage with comparisons to computational methods and flight data obtained during the Orbiter Entry Boundary Layer Flight Experiment and HYTHIRM during STS-119 reentry. These comparisons will facilitate critical updates to be made to the engineering tools employed to make assessments about natural and tripped boundary layer transition during Orbiter reentry. To achieve the goals of this study data was obtained over a range of Mach numbers from 10 to 18, with flight scaled Reynolds numbers and model attitudes representing key points on the Orbiter reentry trajectory. The first of these studies were performed as an integral part of Return to Flight activities following the accident that occurred during the reentry of the Space Shuttle Columbia (STS-107) in February of 2003. This accident was caused by debris, which originated from the foam covering the external tank bipod fitting ramps, striking and damaging critical wing leading edge heating tiles that reside in the Orbiter bow shock/wing interaction region. During investigation of the accident aeroheating team members discovered that only a limited amount of experimental wing leading edge data existed in this critical peak heating area and a need arose to acquire a detailed dataset of heating in this region. This new dataset was acquired in three phases consisting of a risk mitigation phase employing a 1.8% scale Orbiter model with special temperature sensitive paint covering the wing leading edge, a 0.9% scale Orbiter model with high resolution thin-film instrumentation in the span direction, and the primary 1.8% scale Orbiter model with detailed

  17. A study of key features of random atmospheric disturbance models for the approach flight phase

    Science.gov (United States)

    Heffley, R. K.

    1977-01-01

    An analysis and brief simulator experiment were performed to identify and classify important features of random turbulence for the landing approach flight phase. The analysis of various wind models was carried out within the context of the longitudinal closed-loop pilot/vehicle system. The analysis demonstrated the relative importance of atmospheric disturbance scale lengths, horizontal versus vertical gust components, decreasing altitude, and spectral forms of disturbances versus the pilot/vehicle system. Among certain competing wind models, the analysis predicted no significant difference in pilot performance. This was confirmed by a moving base simulator experiment which evaluated the two most extreme models. A number of conclusions were reached: attitude constrained equations do provide a simple but effective approach to describing the closed-loop pilot/vehicle. At low altitudes the horizontal gust component dominates pilot/vehicle performance.

  18. A Flight Dynamics Model for a Multi-Actuated Flexible Rocket Vehicle

    Science.gov (United States)

    Orr, Jeb S.

    2011-01-01

    A comprehensive set of motion equations for a multi-actuated flight vehicle is presented. The dynamics are derived from a vector approach that generalizes the classical linear perturbation equations for flexible launch vehicles into a coupled three-dimensional model. The effects of nozzle and aerosurface inertial coupling, sloshing propellant, and elasticity are incorporated without restrictions on the position, orientation, or number of model elements. The present formulation is well suited to matrix implementation for large-scale linear stability and sensitivity analysis and is also shown to be extensible to nonlinear time-domain simulation through the application of a special form of Lagrange s equations in quasi-coordinates. The model is validated through frequency-domain response comparison with a high-fidelity planar implementation.

  19. The STEP model: Characterizing simultaneous time effects on practice for flight simulator performance among middle-aged and older pilots.

    Science.gov (United States)

    Kennedy, Quinn; Taylor, Joy; Noda, Art; Yesavage, Jerome; Lazzeroni, Laura C

    2015-09-01

    Understanding the possible effects of the number of practice sessions (practice) and time between practice sessions (interval) among middle-aged and older adults in real-world tasks has important implications for skill maintenance. Prior training and cognitive ability may impact practice and interval effects on real-world tasks. In this study, we took advantage of existing practice data from 5 simulated flights among 263 middle-aged and older pilots with varying levels of flight expertise (defined by U.S. Federal Aviation Administration proficiency ratings). We developed a new Simultaneous Time Effects on Practice (STEP) model: (a) to model the simultaneous effects of practice and interval on performance of the 5 flights, and (b) to examine the effects of selected covariates (i.e., age, flight expertise, and 3 composite measures of cognitive ability). The STEP model demonstrated consistent positive practice effects, negative interval effects, and predicted covariate effects. Age negatively moderated the beneficial effects of practice. Additionally, cognitive processing speed and intraindividual variability (IIV) in processing speed moderated the benefits of practice and/or the negative influence of interval for particular flight performance measures. Expertise did not interact with practice or interval. Results indicated that practice and interval effects occur in simulated flight tasks. However, processing speed and IIV may influence these effects, even among high-functioning adults. Results have implications for the design and assessment of training interventions targeted at middle-aged and older adults for complex real-world tasks. (c) 2015 APA, all rights reserved).

  20. Flight model performances of HISUI hyperspectral sensor onboard ISS (International Space Station)

    Science.gov (United States)

    Tanii, Jun; Kashimura, Osamu; Ito, Yoshiyuki; Iwasaki, Akira

    2016-10-01

    Hyperspectral Imager Suite (HISUI) is a next-generation Japanese sensor that will be mounted on Japanese Experiment Module (JEM) of ISS (International Space Station) in 2019 as timeframe. HISUI hyperspectral sensor obtains spectral images of 185 bands with the ground sampling distance of 20x31 meter from the visible to shortwave-infrared region. The sensor system is the follow-on mission of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) in the visible to shortwave infrared region. The critical design review of the instrument was accomplished in 2014. Integration and tests of an flight model of HISUI hyperspectral sensor is being carried out. Simultaneously, the development of JEM-External Facility (EF) Payload system for the instrument started. The system includes the structure, the thermal control system, the electrical system and the pointing mechanism. The development status and the performances including some of the tests results of Instrument flight model, such as optical performance, optical distortion and radiometric performance are reported.

  1. Control for small-speed lateral flight in a model insect

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yanlai; Sun Mao, E-mail: m.sun@buaa.edu.cn [Ministry-of-Education Key Laboratory of Fluid Mechanics, Beijing University of Aeronautics and Astronautics, Beijing (China)

    2011-09-15

    Controls required for small-speed lateral flight of a model insect were studied using techniques based on the linear theories of stability and control (the stability and control derivatives were computed by the method of computational fluid dynamics). The main results are as follows. (1) Two steady-state lateral motions can exist: one is a horizontal side translation with the body rolling to the same side of the translation by a small angle, and the other is a constant-rate yaw rotation (rotation about the vertical axis). (2) The side translation requires an anti-symmetrical change in the stroke amplitudes of the contralateral wings, and/or an anti-symmetrical change in the angles of attack of the contralateral wings, with the down- and upstroke angles of attack of a wing having equal change. The constant-rate yaw rotation requires an anti-symmetrical change in the angles of attack of the contralateral wings, with the down- and upstroke angles of attack of a wing having differential change. (3) For the control of the horizontal side translation, control input required for the steady-state motion has an opposite sign to that needed for initiating the motion. For example, to have a steady-state left side-translation, the insect needs to increase the stroke amplitude of the left wing and decrease that of the right wing to maintain the steady-state flight, but it needs an opposite change in stroke amplitude (decreasing the stroke amplitude of the left wing and increasing that of the right wing) to enter the flight.

  2. 76 FR 14795 - Special Conditions: Gulfstream Model GVI Airplane; Electronic Flight Control System Mode...

    Science.gov (United States)

    2011-03-18

    ...; Electronic Flight Control System Mode Annunciation. AGENCY: Federal Aviation Administration (FAA), DOT... electronic flight control system. The applicable airworthiness regulations do not contain adequate or...). Novel or Unusual Design Features The GVI will have a fly-by-wire electronic flight control system. This...

  3. 76 FR 8278 - Special Conditions: Gulfstream Model GVI Airplane; Enhanced Flight Vision System

    Science.gov (United States)

    2011-02-14

    ... Flight Vision System AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final special conditions..., Airplane and Flight Crew Interface Branch, ANM-111, Transport Standards Staff, Transport Airplane... Design Features The enhanced flight vision system (EFVS) is a novel or unusual design feature because...

  4. Modeling and Flight Data Analysis of Spacecraft Dynamics with a Large Solar Array Paddle

    Science.gov (United States)

    Iwata, Takanori; Maeda, Ken; Hoshino, Hiroki

    2007-01-01

    The Advanced Land Observing Satellite (ALOS) was launched on January 24 2006 and has been operated successfully since then. This satellite has the attitude dynamics characterized by three large flexible structures, four large moving components, and stringent attitude/pointing stability requirements. In particular, it has one of the largest solar array paddles. Presented in this paper are flight data analyses and modeling of spacecraft attitude motion induced by the large solar array paddle. On orbit attitude dynamics was first characterized and summarized. These characteristic motions associated with the solar array paddle were identified and assessed. These motions are thermally induced motion, the pitch excitation by the paddle drive, and the role excitation. The thermally induced motion and the pitch excitation by the paddle drive were modeled and simulated to verify the mechanics of the motions. The control law updates implemented to mitigate the attitude vibrations are also reported.

  5. Free-flight investigation of the stability and control characteristics of a STOL model with an externally blown jet flap

    Science.gov (United States)

    Parlett, L. P.; Emerling, S. J.; Phelps, A. E., III

    1974-01-01

    The stability and control characteristics of a four-engine turbofan STOL transport model having an externally blown jet flap have been investigated by means of the flying-model technique in the Langley full-scale tunnel. The flight characteristics of the model were investigated under conditions of symmetric and asymmetric (one engine inoperative) thrust at lift coefficients up to 9.5 and 5.5, respectively. Static characteristics were studied by conventional power-on force tests over the flight-test angle-of-attack range including the stall. In addition to these tests, dynamic longitudinal and lateral stability calculations were performed for comparison with the flight-test results and for use in correlating the model results with STOL handling-qualities criteria.

  6. Dynamic Flight Stability of a Model Hoverfly in Inclined-Stroke-Plane Hovering

    Institute of Scientific and Technical Information of China (English)

    Xiaolei Mou; Mao Sun

    2012-01-01

    Most hovering insects flap their wings in a horizontal plane,called ‘normal hovering'.But some of the best hoverers,e.g.true hoverflies,hover with an inclined stroke plane.In the present paper,the longitudinal dynamic flight stability of a model hoverfly in inclined-stroke-plane hovering was studied.Computational fluid dynamics was used to compute the aerodynamic derivatives and the eigenvalue and eigenvector analysis was used to solve the equations of motion.The primary findings are as follows.(1) For inclined-stroke-plane hovering,the same three natural modes of motion as those for normal hovering were identified:one unstable oscillatory mode,one stable fast subsidence mode,and one stable slow subsidence mode.The unstable oscillatory mode and the fast subsidence mode mainly have horizontal translation and pitch rotation,and the slow subsidence mode mainly has vertical translation.(2) Because of the existence of the unstable oscillatory mode,inclined-stroke-plane hovering flight is not stable.(3) Although there are large differences in stroke plane and body orientations between the inclined-stroke-plane hovering and normal hovering,the relative position between the mean center of pressure and center of mass for these two cases is not very different,resulting in similar stability derivatives,hence similar dynamic stability properties for these two types of hovering.

  7. Planck pre-launch status: calibration of the Low Frequency Instrument flight model radiometers

    CERN Document Server

    Villa, F; Sandri, M; Meinhold, P; Poutanen, T; Battaglia, P; Franceschet, C; Hughes, N; Laaninen, M; Lapolla, P; Bersanelli, M; Butler, R C; Cuttaia, F; D'Arcangelo, O; Frailis, M; Franceschi, E; Galeotta, S; Gregorio, A; Leonardi, R; Lowe, S R; Mandolesi, N; Maris, M; Mendes, L; Mennella, A; Morgante, G; Stringhetti, L; Tomasi, M; Valenziano, L; Zacchei, A; Zonca, A; Aja, B; Artal, E; Balasini, M; Bernardino, T; Blackhurst, E; Boschini, L; Cappellini, B; Cavaliere, F; Colin, A; Colombo, F; Davis, R J; De La Fuente, L; Edgeley, J; Gaier, T; Galtress, A; Hoyland, R; Jukkala, P; Kettle, D; Kilpia, V-H; Lawrence, C R; Lawson, D; Leahy, J P; Leutenegger, P; Levin, S; Maino, D; Malaspina, M; Mediavilla, A; Miccolis, M; Pagan, L; Pascual, J P; Pasian, F; Pecora, M; Pospieszalski, M; Roddis, N; Salmon, M J; Seiffert, M; Silvestri, R; Simonetto, A; Sjoman, P; Sozzi, C; Tuovinen, J; Varis, J; Wilkinson, A; Winder, F

    2010-01-01

    The Low Frequency Instrument (LFI) on-board the ESA Planck satellite carries eleven radiometer subsystems, called Radiometer Chain Assemblies (RCAs), each composed of a pair of pseudo-correlation receivers. We describe the on-ground calibration campaign performed to qualify the flight model RCAs and to measure their pre-launch performances. Each RCA was calibrated in a dedicated flight-like cryogenic environment with the radiometer front-end cooled to 20K and the back-end at 300K, and with an external input load cooled to 4K. A matched load simulating a blackbody at different temperatures was placed in front of the sky horn to derive basic radiometer properties such as noise temperature, gain, and noise performance, e.g. 1/f noise. The spectral response of each detector was measured as was their susceptibility to thermal variation. All eleven LFI RCAs were calibrated. Instrumental parameters measured in these tests, such as noise temperature, bandwidth, radiometer isolation, and linearity, provide essential i...

  8. An Empirical Correction Method for Improving off-Axes Response Prediction in Component Type Flight Mechanics Helicopter Models

    Science.gov (United States)

    Mansur, M. Hossein; Tischler, Mark B.

    1997-01-01

    Historically, component-type flight mechanics simulation models of helicopters have been unable to satisfactorily predict the roll response to pitch stick input and the pitch response to roll stick input off-axes responses. In the study presented here, simple first-order low-pass filtering of the elemental lift and drag forces was considered as a means of improving the correlation. The method was applied to a blade-element model of the AH-64 APache, and responses of the modified model were compared with flight data in hover and forward flight. Results indicate that significant improvement in the off-axes responses can be achieved in hover. In forward flight, however, the best correlation in the longitudinal and lateral off-axes responses required different values of the filter time constant for each axis. A compromise value was selected and was shown to result in good overall improvement in the off-axes responses. The paper describes both the method and the model used for its implementation, and presents results obtained at hover and in forward flight.

  9. Hovering and targeting flight simulations of a dragonfly-like flapping wing-body model by IB-LBM

    Science.gov (United States)

    Inamuro, Takaji; Hirohashi, Kensuke

    2016-11-01

    Hovering and targeting flights of the dragonfly-like flapping wing-body model are numerically investigated by using the immersed boundary-lattice Boltzmann method (IB-LBM). The governing parameters of the problem are the Reynolds number Re , the Froude number Fr , and the non-dimensional mass m. We set the parameters at Re = 200 , Fr = 15 , and m = 51 . First, we simulate free flights of the model for various values of the phase difference angle ϕ between the forewing and the hindwing motions and for various values of the stroke angle β between the stroke plane and the horizontal plane. We find that the vertical motion of the model depends on the phase difference angle ϕ, and the horizontal motion of the model depends on the stroke angle β. Secondly, using the above results we try to simulate the hovering flight by dynamically changing the phase difference angle ϕ and the stroke angle β. The hovering flight can be successfully simulated by a simple proportional controlleres of the phase difference angle and the stroke angle. Finally, we simualte targeting flight by dynamically changing the stroke angle β. The authors acknowledge the HPCI System Research Project (hp140025 and hp150087) and the Grants-in-Aid Scientific Research (No. 26420108) from JSPS.

  10. Modelling dynamics and aerodynamic tests of a sport parachute jumper during flight in sitfly position.

    Science.gov (United States)

    Moniuszko, Justyna; Maryniak, Jerzy; Ladyżyńska-Kozdraś, Edyta

    2010-01-01

    Based on a model of a parachute jumper, for various body configurations in a sitting position, tests were carried out in an aerodynamic tunnel. Aerodynamic characteristics and dimensionless aerodynamic forces' coefficients were calculated. The tests were carried out for various configurations of the jumper's body. A universal mathematical model of a parachute jumper's body was prepared, thus enabling the analysis of the jumper's movement with a closed parachute in any position. In order to build the model, a digitized model of a jumper allowing changing the body configuration, making appropriate changes of the moment of inertia, distribution of the center of mass and the aerodynamic characteristics was adopted. Dynamic movement equations were derived for a jumper in a relative reference system. The mathematical model was formulated for a jumper with a variable body configuration during the flight, which can be realized through a change of the position and the speed of the parachute jumper's limbs. The model allows analyzing the motion of the jumper with a closed parachute. It is an important jump phase during an assault with delayed parachute opening in sports type jumping, e.g., Skydiving and in emergency jumps from higher altitudes for the parachute's opening to be safe.

  11. A non-linear aeroelastic model for the study of flapping-wing flight

    Science.gov (United States)

    Larijani, Rambod Fayaz

    A non-linear aeroelastic model for the study of flapping-wing flight is presented. This model has been developed to simulate the fully stalled and attached aerodynamic behaviour of a flapping wing and can account for any forcing function. An implicit unconditionally-stable time-marching method known as the Newmark method is used to accurately model the non-linear stalled and attached flow regimes. An iteration procedure is performed at each time step to eliminate any errors associated with the temporal discretization process. A finite element formulation is used to model the elastic behaviour of the wing which is composed of a leading edge composite spar and light-weight rigid ribs covered with fabric. A viscous damping model is used to simulate the structural damping of the wing. The Newmark code generates instantaneous lift and thrust values as well as torsional and bending moments along the wing span. Average lift values are in good agreement with experimental results obtained from tests performed on a scaled down model of the ornithopter at the NRC wind tunnel in Ottawa. Furthermore, bending and twisting moments obtained from strain gages embedded in the full-scale ornithopter's wing spar show that the predicted instantaneous moments are also quite accurate. Also, comparisons with experimental data show that the Newmark code can accurately predict the twisting behaviour of the wing for zero forward speed as well as cruise conditions.

  12. Flight assessment of the onboard propulsion system model for the Performance Seeking Control algorithm on an F-15 aircraft

    Science.gov (United States)

    Orme, John S.; Schkolnik, Gerard S.

    1995-01-01

    Performance Seeking Control (PSC), an onboard, adaptive, real-time optimization algorithm, relies upon an onboard propulsion system model. Flight results illustrated propulsion system performance improvements as calculated by the model. These improvements were subject to uncertainty arising from modeling error. Thus to quantify uncertainty in the PSC performance improvements, modeling accuracy must be assessed. A flight test approach to verify PSC-predicted increases in thrust (FNP) and absolute levels of fan stall margin is developed and applied to flight test data. Application of the excess thrust technique shows that increases of FNP agree to within 3 percent of full-scale measurements for most conditions. Accuracy to these levels is significant because uncertainty bands may now be applied to the performance improvements provided by PSC. Assessment of PSC fan stall margin modeling accuracy was completed with analysis of in-flight stall tests. Results indicate that the model overestimates the stall margin by between 5 to 10 percent. Because PSC achieves performance gains by using available stall margin, this overestimation may represent performance improvements to be recovered with increased modeling accuracy. Assessment of thrust and stall margin modeling accuracy provides a critical piece for a comprehensive understanding of PSC's capabilities and limitations.

  13. Flying with the wind: scale dependency of speed and direction measurements in modelling wind support in avian flight

    Science.gov (United States)

    Safi, Kamran; Kranstauber, Bart; Weinzierl, Rolf P.; Griffin, Larry; Reese, Eileen C.; Cabot, David; Cruz, Sebastian; Proaño, Carolina; Takekawa, John Y.; Newman, Scott H.; Waldenström, Jonas; Bengtsson, Daniel; Kays, Roland; Wikelski, Martin; Bohrer, Gil

    2013-01-01

    Background: Understanding how environmental conditions, especially wind, influence birds' flight speeds is a prerequisite for understanding many important aspects of bird flight, including optimal migration strategies, navigation, and compensation for wind drift. Recent developments in tracking technology and the increased availability of data on large-scale weather patterns have made it possible to use path annotation to link the location of animals to environmental conditions such as wind speed and direction. However, there are various measures available for describing not only wind conditions but also the bird's flight direction and ground speed, and it is unclear which is best for determining the amount of wind support (the length of the wind vector in a bird’s flight direction) and the influence of cross-winds (the length of the wind vector perpendicular to a bird’s direction) throughout a bird's journey. Results: We compared relationships between cross-wind, wind support and bird movements, using path annotation derived from two different global weather reanalysis datasets and three different measures of direction and speed calculation for 288 individuals of nine bird species. Wind was a strong predictor of bird ground speed, explaining 10-66% of the variance, depending on species. Models using data from different weather sources gave qualitatively similar results; however, determining flight direction and speed from successive locations, even at short (15 min intervals), was inferior to using instantaneous GPS-based measures of speed and direction. Use of successive location data significantly underestimated the birds' ground and airspeed, and also resulted in mistaken associations between cross-winds, wind support, and their interactive effects, in relation to the birds' onward flight. Conclusions: Wind has strong effects on bird flight, and combining GPS technology with path annotation of weather variables allows us to quantify these effects for

  14. Generic icing effects on forward flight performance of a model helicopter rotor

    Science.gov (United States)

    Tinetti, Ana F.; Korkan, Kenneth D.

    1989-01-01

    An experimental program using a commercially available model helicopter has been conducted in the TAMU 7 ft x 10 ft Subsonic Wind Tunnel to investigate main rotor performance degradation due to generic ice adhesion. Base and iced performance data were gathered as functions of fuselage incidence, blade collective pitch, main rotor rotational velocity, and freestream velocity. The experimental values have shown that, in general, the presence of generic ice introduces decrements in performance caused by leading edge separation regions and increased surface roughness. In addition to the expected changes in aerodynamic forces caused by variations in test Reynolds number, forward flight data seemed to be influenced by changes in freestream and rotational velocity. The dependence of the data upon such velocity variations was apparently enhanced by increases in blade chord.

  15. Generic icing effects on forward flight performance of a model helicopter rotor

    Science.gov (United States)

    Tinetti, Ana F.; Korkan, Kenneth D.

    1989-01-01

    An experimental program using a commercially available model helicopter has been conducted in the TAMU 7 ft x 10 ft Subsonic Wind Tunnel to investigate main rotor performance degradation due to generic ice adhesion. Base and iced performance data were gathered as functions of fuselage incidence, blade collective pitch, main rotor rotational velocity, and freestream velocity. The experimental values have shown that, in general, the presence of generic ice introduces decrements in performance caused by leading edge separation regions and increased surface roughness. In addition to the expected changes in aerodynamic forces caused by variations in test Reynolds number, forward flight data seemed to be influenced by changes in freestream and rotational velocity. The dependence of the data upon such velocity variations was apparently enhanced by increases in blade chord.

  16. Interface Management for a NASA Flight Project Using Model-Based Systems Engineering (MBSE)

    Science.gov (United States)

    Vipavetz, Kevin; Shull, Thomas A.; Infeld, Samatha; Price, Jim

    2016-01-01

    The goal of interface management is to identify, define, control, and verify interfaces; ensure compatibility; provide an efficient system development; be on time and within budget; while meeting stakeholder requirements. This paper will present a successful seven-step approach to interface management used in several NASA flight projects. The seven-step approach using Model Based Systems Engineering will be illustrated by interface examples from the Materials International Space Station Experiment-X (MISSE-X) project. The MISSE-X was being developed as an International Space Station (ISS) external platform for space environmental studies, designed to advance the technology readiness of materials and devices critical for future space exploration. Emphasis will be given to best practices covering key areas such as interface definition, writing good interface requirements, utilizing interface working groups, developing and controlling interface documents, handling interface agreements, the use of shadow documents, the importance of interface requirement ownership, interface verification, and product transition.

  17. Aircraft automatic digital flight control system with inversion of the model in the feed-forward path

    Science.gov (United States)

    Smith, G. A.; Meyer, G.

    1984-01-01

    A full-flight-envelope automatic trajectory control system concept is being investigated at Ames Research Center. This concept was developed for advanced aircraft configurations with severe nonlinear characteristics. A feature of the system is an inverse of the complete nonlinear aircraft model as part of the feed-forward control path. Simulation and flight tests have been reported at previous Digital Avionics Systems conferences. A new method for the continuous real-time inversion of the aircraft model using a Newton-Raphson trim algorithm instead of the original inverse table look-up procedure has been developed. The results of a simulation study of a vertical attitude takeoff and landing aircraft using the new inversion technique are presented. Maneuvers were successfully carried out in all directions in the vertical-attitude hover mode. Transition runs from conventional flight through the region of lift-curve-slope reversal at an angle of attack of about 32 deg and to hover at zero speed in the vertical attitude showed satisfactory transient response. Simulations were also conducted in conventional flight at high subsonic speed in steep climb and with turns up to 4 g. Successful flight tests of the system with the new model-inversion technique in a UH-1H helicopter have recently been carried out.

  18. Triiodothyronine increases calcium loss in a bed rest antigravity model for space flight.

    Science.gov (United States)

    Smith, Steven R; Lovejoy, Jennifer C; Bray, George A; Rood, Jennifer; Most, Marlene M; Ryan, Donna H

    2008-12-01

    Bed rest has been used as a model to simulate the effects of space flight on bone metabolism. Thyroid hormones accelerate bone metabolism. Thus, supraphysiologic doses of this hormone might be used as a model to accelerate bone metabolism during bed rest and potentially simulate space flight. The objective of the study was to quantitate the changes in bone turnover after low doses of triiodothyronine (T(3)) added to short-term bed rest. Nine men and 5 women were restricted to bed rest for 28 days with their heads positioned 6 degrees below their feet. Subjects were randomly assigned to receive either placebo or oral T(3) at doses of 50 to 75 microg/d in a single-blind fashion. Calcium balance was measured over 5-day periods; and T(3), thyroxine, thyroid-stimulating hormone, immunoreactive parathyroid hormone, osteocalcin, bone alkaline phosphatase, and urinary deoxypyridinoline were measured weekly. Triiodothyronine increased 2-fold in the men and 5-fold in the women during treatment, suppressing both thyroxine and thyroid-stimulating hormone. Calcium balance was negative by 300 to 400 mg/d in the T(3)-treated volunteers, primarily because of the increased fecal loss that was not present in the placebo group. Urinary deoxypyridinoline to creatinine ratio, a marker of bone resorption, increased 60% in the placebo group during bed rest, but more than doubled in the T(3)-treated subjects (P < .01), suggesting that bone resorption was enhanced by treatment with T(3). Changes in serum osteocalcin and bone-specific alkaline phosphatase, markers of bone formation, were similar in T(3)- and placebo-treated subjects. Triiodothyronine increases bone resorption and fecal calcium loss in subjects at bed rest.

  19. Flight dynamics simulation modeling and control of a large flexible tiltrotor aircraft

    Science.gov (United States)

    Juhasz, Ondrej

    A high order rotorcraft mathematical model is developed and validated against the XV-15 and a Large Civil Tiltrotor (LCTR) concept. The mathematical model is generic and allows for any rotorcraft configuration, from single main rotor helicopters to coaxial and tiltrotor aircraft. Rigid-body and inflow states, as well as flexible wing and blade states are used in the analysis. The separate modeling of each rotorcraft component allows for structural flexibility to be included, which is important when modeling large aircraft where structural modes affect the flight dynamics frequency ranges of interest, generally 1 to 20 rad/sec. Details of the formulation of the mathematical model are given, including derivations of structural, aerodynamic, and inertial loads. The linking of the components of the aircraft is developed using an approach similar to multibody analyses by exploiting a tree topology, but without equations of constraints. Assessments of the effects of wing flexibility are given. Flexibility effects are evaluated by looking at the nature of the couplings between rigid-body modes and wing structural modes and vice versa. The effects of various different forms of structural feedback on aircraft dynamics are analyzed. A proportional-integral feedback on the structural acceleration is deemed to be most effective at both improving the damping and reducing the overall excitation of a structural mode. A model following control architecture is then implemented on full order flexible LCTR models. For this aircraft, the four lowest frequency structural modes are below 20 rad/sec, and are thus needed for control law development and analysis. The impact of structural feedback on both Attitude-Command, Attitude-Hold (ACAH) and Translational Rate Command (TRC) response types are investigated. A rigid aircraft model has optimistic performance characteristics, and a control system designed for a rigid aircraft could potentially destabilize a flexible one. The various

  20. Infrared signature modelling of a rocket jet plume - comparison with flight measurements

    Science.gov (United States)

    Rialland, V.; Guy, A.; Gueyffier, D.; Perez, P.; Roblin, A.; Smithson, T.

    2016-01-01

    The infrared signature modelling of rocket plumes is a challenging problem involving rocket geometry, propellant composition, combustion modelling, trajectory calculations, fluid mechanics, atmosphere modelling, calculation of gas and particles radiative properties and of radiative transfer through the atmosphere. This paper presents ONERA simulation tools chained together to achieve infrared signature prediction, and the comparison of the estimated and measured signatures of an in-flight rocket plume. We consider the case of a solid rocket motor with aluminized propellant, the Black Brant sounding rocket. The calculation case reproduces the conditions of an experimental rocket launch, performed at White Sands in 1997, for which we obtained high quality infrared signature data sets from DRDC Valcartier. The jet plume is calculated using an in-house CFD software called CEDRE. The plume infrared signature is then computed on the spectral interval 1900-5000 cm-1 with a step of 5 cm-1. The models and their hypotheses are presented and discussed. Then the resulting plume properties, radiance and spectra are detailed. Finally, the estimated infrared signature is compared with the spectral imaging measurements. The discrepancies are analyzed and discussed.

  1. The Integrated Computational Environment for Airbreathing Hypersonic Flight Vehicle Modeling and Design Evaluation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An integrated computational environment for multidisciplinary, physics-based simulation and analyses of airbreathing hypersonic flight vehicles will be developed....

  2. Airline Choice for Domestic Flights in Sao Paulo Metropolitan Area: An Application of the Conditional Logit Model

    Science.gov (United States)

    Moreno, Marcelo Baena

    2006-01-01

    Using the conditional (multinomial) LOGIT model, this paper addresses airline choice in the S o Paulo Metropolitan Area. There are two airports in this region, where two, three or even four airlines compete for passengers flying to an array of domestic destinations. The airline choice is believed to be a result of the tradeoff passengers face among flight cost, flight frequency and airline performance. It was found that the lowest fare better explains airline choice than the highest fare, whereas direct flight frequencies give better explanation to airline choice than indirect (connections and stops) and total (direct plus indirect) ones. Out of 15 variables tested, the lowest fare was the variable that best explained airline choice. However, its signal was counterintuitive (positive) possibly because the cheapest airline was offering few flights, so passengers overwhelmingly failed to choose the cheapest airline. The model specification most adjusted to the data considered the lowest fare, direct flight frequency in the travel day and period (morning or afternoon peak) and airline age. Passengers departing from S o Paulo-Guarulhos International Airport (GRU) airport make their airline choice in terms of cost whereas those from Sao Paulo-Congonhas Airport (CGH) airport do not. Finally, senior passengers place more importance on airline age than junior passengers.

  3. Lévy flight with absorption: A model for diffusing diffusivity with long tails

    Science.gov (United States)

    Jain, Rohit; Sebastian, K. L.

    2017-03-01

    We consider diffusion of a particle in rearranging environment, so that the diffusivity of the particle is a stochastic function of time. In our previous model of "diffusing diffusivity" [Jain and Sebastian, J. Phys. Chem. B 120, 3988 (2016), 10.1021/acs.jpcb.6b01527], it was shown that the mean square displacement of particle remains Fickian, i.e., ∝T at all times, but the probability distribution of particle displacement is not Gaussian at all times. It is exponential at short times and crosses over to become Gaussian only in a large time limit in the case where the distribution of D in that model has a steady state limit which is exponential, i.e., πe(D ) ˜e-D /D0 . In the present study, we model the diffusivity of a particle as a Lévy flight process so that D has a power-law tailed distribution, viz., πe(D ) ˜D-1 -α with 0 <α <1 . We find that in the short time limit, the width of displacement distribution is proportional to √{T }, implying that the diffusion is Fickian. But for long times, the width is proportional to T1 /2 α which is a characteristic of anomalous diffusion. The distribution function for the displacement of the particle is found to be a symmetric stable distribution with a stability index 2 α which preserves its shape at all times.

  4. Numerical model for computation of effective and ambient dose equivalent at flight altitudes

    Directory of Open Access Journals (Sweden)

    Mishev Alexander

    2015-01-01

    Full Text Available A numerical model for assessment of the effective dose and ambient dose equivalent produced by secondary cosmic ray particles of galactic and solar origin at commercial aircraft altitudes is presented. The model represents a full chain analysis based on ground-based measurements of cosmic rays, from particle spectral and angular characteristics to dose estimation. The model is based on newly numerically computed yield functions and realistic propagation of cosmic ray in the Earth magnetosphere. The yield functions are computed using a straightforward full Monte Carlo simulation of the atmospheric cascade induced by primary protons and α-particles and subsequent conversion of secondary particle fluence (neutrons, protons, gammas, electrons, positrons, muons and charged pions to effective dose or the ambient dose equivalent. The ambient dose equivalent is compared with reference data at various conditions such as rigidity cut-off and level of solar activity. The method is applied for computation of the effective dose rate at flight altitude during the ground level enhancement of 13 December 2006. The solar proton spectra are derived using neutron monitor data. The computation of the effective dose rate during the event explicitly considers the derived anisotropy i.e. the pitch angle distribution as well as the propagation of the solar protons in the magnetosphere of the Earth.

  5. CFD based aerodynamic modeling to study flight dynamics of a flapping wing micro air vehicle

    Science.gov (United States)

    Rege, Alok Ashok

    The demand for small unmanned air vehicles, commonly termed micro air vehicles or MAV's, is rapidly increasing. Driven by applications ranging from civil search-and-rescue missions to military surveillance missions, there is a rising level of interest and investment in better vehicle designs, and miniaturized components are enabling many rapid advances. The need to better understand fundamental aspects of flight for small vehicles has spawned a surge in high quality research in the area of micro air vehicles. These aircraft have a set of constraints which are, in many ways, considerably different from that of traditional aircraft and are often best addressed by a multidisciplinary approach. Fast-response non-linear controls, nano-structures, integrated propulsion and lift mechanisms, highly flexible structures, and low Reynolds aerodynamics are just a few of the important considerations which may be combined in the execution of MAV research. The main objective of this thesis is to derive a consistent nonlinear dynamic model to study the flight dynamics of micro air vehicles with a reasonably accurate representation of aerodynamic forces and moments. The research is divided into two sections. In the first section, derivation of the nonlinear dynamics of flapping wing micro air vehicles is presented. The flapping wing micro air vehicle (MAV) used in this research is modeled as a system of three rigid bodies: a body and two wings. The design is based on an insect called Drosophila Melanogaster, commonly known as fruit-fly. The mass and inertial effects of the wing on the body are neglected for the present work. The nonlinear dynamics is simulated with the aerodynamic data published in the open literature. The flapping frequency is used as the control input. Simulations are run for different cases of wing positions and the chosen parameters are studied for boundedness. Results show a qualitative inconsistency in boundedness for some cases, and demand a better

  6. Model and Sensor Based Nonlinear Adaptive Flight Control with Online System Identification

    NARCIS (Netherlands)

    Sun, L.G.

    2014-01-01

    Consensus exists that many loss-of-control (LOC) in flight accidents caused by severe aircraft damage or system failure could be prevented if flight performance could be recovered using the valid and remaining control authorities. However, the safe maneuverability of a post-failure aircraft will

  7. An Integrated Approach to Aircraft Modelling and Flight Control Law Design

    NARCIS (Netherlands)

    Looye, G.H.N.

    2008-01-01

    The design of flight control laws (FCLs) for automatic and manual (augmented) control of aircraft is a complicated task. FCLs have to fulfil large amounts of performance criteria and must work reliably in all flight conditions, for all aircraft configurations, and in adverse weather conditions.

  8. An Integrated Approach to Aircraft Modelling and Flight Control Law Design

    NARCIS (Netherlands)

    Looye, G.H.N.

    2008-01-01

    The design of flight control laws (FCLs) for automatic and manual (augmented) control of aircraft is a complicated task. FCLs have to fulfil large amounts of performance criteria and must work reliably in all flight conditions, for all aircraft configurations, and in adverse weather conditions. Cons

  9. Model and Sensor Based Nonlinear Adaptive Flight Control with Online System Identification

    NARCIS (Netherlands)

    Sun, L.G.

    2014-01-01

    Consensus exists that many loss-of-control (LOC) in flight accidents caused by severe aircraft damage or system failure could be prevented if flight performance could be recovered using the valid and remaining control authorities. However, the safe maneuverability of a post-failure aircraft will ine

  10. 78 FR 11562 - Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Flight Envelope Protection: High Speed...

    Science.gov (United States)

    2013-02-19

    ... Embraer S.A. Model EMB-550 airplanes was published in the Federal Register on November 20, 2012 (77 FR...; Flight Envelope Protection: High Speed Limiting AGENCY: Federal Aviation Administration (FAA), DOT... inadvertently or intentionally exceeding a speed approximately equivalent to V FC or attaining V DF ....

  11. Model of Dynamic Pricing for Two Parallels Flights with Multiple Fare Classes Based on Passenger Choice Behavior

    Directory of Open Access Journals (Sweden)

    Ahmad Rusdiansyah

    2010-01-01

    Full Text Available Airline revenue management (ARM is one of emerging topics in transportation logistics areas. This paper discusses a problem in ARM which is dynamic pricing for two parallel flights owned by the same airline. We extended the existing model on Joint Pricing Model for Parallel Flights under passenger choice behavior in the literature. We generalized the model to consider multiple full-fare class instead of only single full-fare class. Consequently, we have to define the seat allocation for each fare class beforehand. We have combined the joint pricing model and the model of nested Expected Marginal Seat Revenue (EMSR model. To solve this hybrid model, we have developed a dynamic programming-based algorithm. We also have conducted numerical experiments to show the behavior of our model. Our experiment results have showed that the expected revenue of both flights significantly induced by the proportion of the time flexible passengers and the number of allocated seat in each full-fare class. As managerial insights, our model has proved that there is a closed relationship between demand management, which is represented by the price of each fare class, and total expected revenue considering the passenger choice behavior.

  12. T-tail flutter: Potential-flow modelling, experimental validation and flight tests

    Science.gov (United States)

    Murua, Joseba; Martínez, Pablo; Climent, Héctor; van Zyl, Louw; Palacios, Rafael

    2014-11-01

    parametric studies illustrate the impact of well-known factors in T-tail flutter, namely horizontal tailplane dihedral, flexibility and static deformations. In addition, scenarios are exposed in which the stability behaviour is dictated by typically second-order effects, such as chordwise forces and quadratic modes, revealing drastically different qualitative flutter curves. It is also shown that there is a distinction between angle of attack of the whole tail assembly and incidence of the horizontal tailplane relative to the fin, which might yield very counterintuitive trends depending on the configuration parameters. The paper concludes with flight test results of the Airbus A400M, epitome of modern T-tail aircraft. Tests performed in a wake-vortex encounter campaign complement the virtually nonexistent literature in the topic, demonstrate how T-tail effects can be measured in flight and restate the adequacy of potential-flow models for T-tail flutter prediction.

  13. Impaired Compensation for Salt-Induced Urinary Calcium Loss in a Space Flight Model

    Science.gov (United States)

    Navidi, Meena; Harper, J. S.; Evans, J.; Fung, P.; Wolinsky, I.; Arnaud, S. B.; Wade, Charles E. (Technical Monitor)

    1994-01-01

    The loss of urinary calcium (UCa) induced by high sodium (HiNa) diets is compensated for by an increase in net intestinal Ca absorption (abs.). To determine the capacity of the intestine to absorb Ca in a space flight model in which the formation of 1,25-dihydroxyvitamin D (1,25-D) is suppressed, we induced Ca loss with HiNa diets (8%) and restricted dietary Ca (0.2%). In 200 g rats with hind limbs unloaded by tail suspension (S), we examined intestinal Ca abs. by direct measurement in the duodenum (everted gut sac or S/M), vitamin D receptors (VDR) and Ca balance. We also measured serum ionized calcium (ICa), pH, parathyroid hormone (PTH) and 1,25D. PTH was related to ICa (r = -0.44, p is less than 0.02), pH (r = -0.47, p is less than 0.02) and %Ca abs. (r = -0.40, p is less than 0.05). 1,25-D was related to %Ca abs. (r = 0.60, p is less than 0.001) but not VDR or S/M. Effects of the model were lower serum 1,25-D (110 +/- 59 vs. 199 +/- 80 pg/ml, p is less than 0.005), %Ca abs. (83 +/- 6.9 vs. 93 +/- 3.2, p is less than 0.03) and Ca balance (27 +/- 0.2 vs. 30 +/- 0.3 mg/d, p is less than 0.001) in S than controls (C). The HiNa diet increased UCa excretion from 2 to 13% of dietary Ca. Responses to HiNa diets, compared to normal Na, revealed no differences in 1,25-D, Ca abs. or VDR. Ca balances were lower in HiNa (27 +/- 0.3 vs. 30 +/- 0.4 mg/d, p is less than 0.001) in spite of higher Ca intakes. The failure of S rats fed HiNa diets to increase Ca abs. in response to Na-induced Ca loss appears to be related to suppressed 1,25-D in the space flight model, the cause of which remains obscure.

  14. A Hybrid Method Combining Improved K-means Algorithm with BADA Model for Generating Nominal Flight Profiles

    Institute of Scientific and Technical Information of China (English)

    TangXinmin; GuJunwei; ShenZhiyuan; ChenPing; LiBo

    2016-01-01

    A high-precision nominal flight profile,involving controllers′intentions is critical for 4D traj ectory esti-mation in modern automatic air traffic control systems.We proposed a novel method to effectively improve the ac-curacy of the nominal flight profile,including the nominal altitude profile and the speed profile.First,considering the characteristics of traj ectory data,we developed an improved K-means algorithm.The approach was to measure the similarity between different altitude profiles by integrating the space warp edit distance algorithm,thereby to acquire several fitted nominal flight altitude profiles.This approach breaks the constraints of traditional K-means algorithms.Second,to eliminate the influence of meteorological factors,we introduced historical gridded binary data to determine the en-route wind speed and temperature via inverse distance weighted interpolation.Finally,we facilitated the true airspeed determined by speed triangle relationships and the calibrated airspeed determined by aircraft data model to extract a more accurate nominal speed profile from each cluster,therefore we could describe the airspeed profiles above and below the airspeed transition altitude,respectively.Our experimental results showed that the proposed method could obtain a highly accurate nominal flight profile,which reflects the actual aircraft flight status.

  15. Levy flights and self-similar exploratory behaviour of termite workers: beyond model fitting.

    Directory of Open Access Journals (Sweden)

    Octavio Miramontes

    Full Text Available Animal movements have been related to optimal foraging strategies where self-similar trajectories are central. Most of the experimental studies done so far have focused mainly on fitting statistical models to data in order to test for movement patterns described by power-laws. Here we show by analyzing over half a million movement displacements that isolated termite workers actually exhibit a range of very interesting dynamical properties--including Lévy flights--in their exploratory behaviour. Going beyond the current trend of statistical model fitting alone, our study analyses anomalous diffusion and structure functions to estimate values of the scaling exponents describing displacement statistics. We evince the fractal nature of the movement patterns and show how the scaling exponents describing termite space exploration intriguingly comply with mathematical relations found in the physics of transport phenomena. By doing this, we rescue a rich variety of physical and biological phenomenology that can be potentially important and meaningful for the study of complex animal behavior and, in particular, for the study of how patterns of exploratory behaviour of individual social insects may impact not only their feeding demands but also nestmate encounter patterns and, hence, their dynamics at the social scale.

  16. Modeling and HIL Simulation of Flight Conditions Simulating Control System for the Altitude Test Facility

    Science.gov (United States)

    Zhou, Jun; Shen, Li; Zhang, Tianhong

    2016-12-01

    Simulated altitude test is an essential exploring, debugging, verification and validation means during the development of aero-engine. Free-jet engine test can simulate actual working conditions of aero-engine more realistically than direct-connect engine test but with relatively lower cost compared to propulsion wind tunnel test, thus becoming an important developing area of simulated altitude test technology. The Flight Conditions Simulating Control System (FCSCS) is of great importance to the Altitude Test Facility (ATF) but the development of that is a huge challenge. Aiming at improving the design efficiency and reducing risks during the development of FCSCS for ATFs, a Hardware- in-the-Loop (HIL) simulation system was designed and the mathematical models of key components such as the pressure stabilizing chamber, free-jet nozzle, control valve and aero-engine were built in this paper. Moreover, some HIL simulation experiments were carried out. The results show that the HIL simulation system designed and established in this paper is reasonable and effective, which can be used to adjust control parameters conveniently and assess the software and hardware in the control system immediately.

  17. Modeling simulation of the thermal radiation for high-speed flight vehicles' aero-optical windows

    Science.gov (United States)

    Chen, Lei; Zhang, Liqin; Guo, Mingjiang

    2015-10-01

    When high-speed flight vehicles fly in the atmosphere, they can generate serious aero-optical effect. The optical window temperature rises sharply because of aerodynamic heating. It will form radiation interference that can lead infrared detectors to producing non-uniform radiation backgrounds, decreasing system SNR and detection range. Besides, there exits temperature difference due to uneven heating. Under the thermo-optical and elastic-optical effects, optical windows change into inhomogeneous mediums which influence the ray propagation. In this paper, a model of thermal radiation effect was built by a finite element analysis method. Firstly, the optical window was divided into uniform grids. Then, radiation distribution on the focal planes at different angles of the window's normal line and optical axis was obtained by tracing light rays of each grid. Finally, simulation results indicate that radiation distribution reflects the two directions-the length and width-of temperature distribution, and the change of angle causes the center of radiation distribution to shift to one direction of the image surface under the same window temperature.

  18. Unsteady Velocity Measurements Taken Behind a Model Helicopter Rotor Hub in Forward Flight

    Science.gov (United States)

    Berry, John D.

    1997-01-01

    Drag caused by separated flow behind the hub of a helicopter has an adverse effect on aerodynamic performance of the aircraft. To determine the effect of separated flow on a configuration used extensively for helicopter aerodynamic investigations, an experiment was conducted using a laser velocimeter to measure velocities in the wake of a model helicopter hub operating at Mach-scaled conditions in forward flight. Velocity measurements were taken using a laser velocimeter with components in the vertical and downstream directions. Measurements were taken at 13 stations downstream from the rotor hub. At each station, measurements were taken in both a horizontal and vertical row of locations. These measurements were analyzed for harmonic content based on the rotor period of revolution. After accounting for these periodic velocities, the remaining unsteady velocities were treated as turbulence. Turbulence intensity distributions are presented. Average turbulent intensities ranged from approximately 2 percent of free stream to over 15 percent of free stream at specific locations and azimuths. The maximum average value of turbulence was located near the rear-facing region of the fuselage.

  19. Modelling and simulation of flight control electromechanical actuators with special focus on model architecting, multidisciplinary effects and power flows

    Institute of Scientific and Technical Information of China (English)

    Fu Jian; Jean-Charles Maré; Fu Yongling

    2017-01-01

    In the aerospace field, electromechanical actuators are increasingly being implemented in place of conventional hydraulic actuators. For safety-critical embedded actuation applications like flight controls, the use of electromechanical actuators introduces specific issues related to thermal balance, reflected inertia, parasitic motion due to compliance and response to failure. Unfortu-nately, the physical effects governing the actuator behaviour are multidisciplinary, coupled and nonlinear. Although numerous multi-domain and system-level simulation packages are now avail-able on the market, these effects are rarely addressed as a whole because of a lack of scientific approaches for model architecting, multi-purpose incremental modelling and judicious model implementation. In this publication, virtual prototyping of electromechanical actuators is addressed using the Bond-Graph formalism. New approaches are proposed to enable incremental modelling, thermal balance analysis, response to free-run or jamming faults, impact of compliance on parasitic motion, and influence of temperature. A special focus is placed on friction and compliance of the mechanical transmission with fault injection and temperature dependence. Aileron actuation is used to highlight the proposals for control design, energy consumption and thermal analysis, power net-work pollution analysis and fault response.

  20. Modelling and simulation of flight control electromechanical actuators with special focus on model architecting, multidisciplinary effects and power flows

    Directory of Open Access Journals (Sweden)

    Jian Fu

    2017-02-01

    Full Text Available In the aerospace field, electromechanical actuators are increasingly being implemented in place of conventional hydraulic actuators. For safety-critical embedded actuation applications like flight controls, the use of electromechanical actuators introduces specific issues related to thermal balance, reflected inertia, parasitic motion due to compliance and response to failure. Unfortunately, the physical effects governing the actuator behaviour are multidisciplinary, coupled and nonlinear. Although numerous multi-domain and system-level simulation packages are now available on the market, these effects are rarely addressed as a whole because of a lack of scientific approaches for model architecting, multi-purpose incremental modelling and judicious model implementation. In this publication, virtual prototyping of electromechanical actuators is addressed using the Bond-Graph formalism. New approaches are proposed to enable incremental modelling, thermal balance analysis, response to free-run or jamming faults, impact of compliance on parasitic motion, and influence of temperature. A special focus is placed on friction and compliance of the mechanical transmission with fault injection and temperature dependence. Aileron actuation is used to highlight the proposals for control design, energy consumption and thermal analysis, power network pollution analysis and fault response.

  1. Aircraft Flight Envelope Identification through On-Board Model Based Estimation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To improve aviation safety with anticipated growth in capacity, it is necessary to develop flight control technologies that enable safe operations as anomalous...

  2. 77 FR 21861 - Special Conditions: Boeing, Model 777F; Enhanced Flight Vision System

    Science.gov (United States)

    2012-04-12

    ..., anyone can find and read the electronic form of all comments received into any FAA docket, including the..., and overlay that imagery with alpha-numeric and symbolic flight information. However, the term...

  3. 78 FR 32078 - Special Conditions: Gulfstream Model G280 Airplane, Enhanced Flight Vision System (EFVS) With...

    Science.gov (United States)

    2013-05-29

    ... electronic form of all comments received into any FAA docket, including the name of the individual sending... imagery on the HUD, and which overlay that imagery with alpha-numeric and symbolic flight...

  4. Rapid Development of Guidance, Navigation, and Control Core Flight System Software Applications Using Simulink Models Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We will demonstrate the usefulness of SIL for GSFC missions by attempting to compile the SIL source code with an autocoded sample GNC application flight software....

  5. Evolution of the 'Trick' Dynamic Software Executive and Model Libraries for Reusable Flight Software Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to a need for cost-effective small satellite missions, Odyssey Space Research is proposing the development of a common flight software executive and a...

  6. Understanding metabolic alterations in space flight using quantitative models - Fluid and energy balance

    Science.gov (United States)

    Leonard, J. I.

    1985-01-01

    The results of an integrated multidisciplinary and multiexperimental investigation, using data from the Skylab program, of metabolic adaptation to space flight are summarized and discussed. The effects of space flight on fluid-electrolyte regulation, mechanisms of hormone disturbances, energy balance, and the etiology of weight loss are emphasized. A composite picture of the fluid, electrolyte, and energy response to weightlessness, based primarily on data gathered from the nine Skylab crewmen, is presented.

  7. Critical paths in a metapopulation model of H1N1: Efficiently delaying influenza spreading through flight cancellation

    CERN Document Server

    Marcelino, Jose; 10.1371/4f8c9a2e1fca8

    2012-01-01

    Disease spreading through human travel networks has been a topic of great interest in recent years, as witnessed during outbreaks of influenza A (H1N1) or SARS pandemics. One way to stop spreading over the airline network are travel restrictions for major airports or network hubs based on the total number of passengers of an airport. Here, we test alternative strategies using edge removal, cancelling targeted flight connections rather than restricting traffic for network hubs, for controlling spreading over the airline network. We employ a SEIR metapopulation model that takes into account the population of cities, simulates infection within cities and across the network of the top 500 airports, and tests different flight cancellation methods for limiting the course of infection. The time required to spread an infection globally, as simulated by a stochastic global spreading model was used to rank the candidate control strategies. The model includes both local spreading dynamics at the level of populations and...

  8. High-Resolution Mesoscale Model Setup for the Eastern Range and Wallops Flight Facility

    Science.gov (United States)

    Watson, Leela R.; Zavodsky, Bradley T.

    2015-01-01

    Mesoscale weather conditions can have an adverse effect on space launch, landing, ground processing, and weather advisories, watches, and warnings at the Eastern Range (ER) in Florida and Wallops Flight Facility (WFF) in Virginia. During summer, land-sea interactions across Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) lead to sea breeze front formation, which can spawn deep convection that can hinder operations and endanger personnel and resources. Many other weak locally-driven low-level boundaries and their interactions with the sea breeze front and each other can also initiate deep convection in the KSC/CCAFS area. These convective processes often last 60 minutes or less and pose a significant challenge to the local forecasters. Surface winds during the transition seasons (spring and fall) pose the most difficulties for the forecasters at WFF. They also encounter problems forecasting convective activity and temperature during those seasons. Therefore, accurate mesoscale model forecasts are needed to better forecast a variety of unique weather phenomena. Global and national scale models cannot properly resolve important local-scale weather features at each location due to their horizontal resolutions being much too coarse. Therefore, a properly tuned local data assimilation (DA) and forecast model at a high resolution is needed to provide improved capability. To accomplish this, a number of sensitivity tests were performed using the Weather Research and Forecasting (WRF) model in order to determine the best DA/model configuration for operational use at each of the space launch ranges to best predict winds, precipitation, and temperature. A set of Perl scripts to run the Gridpoint Statistical Interpolation (GSI)/WRF in real-time were provided by NASA's Short-term Prediction Research and Transition Center (SPoRT). The GSI can analyze many types of observational data including satellite, radar, and conventional data. The GSI/WRF scripts

  9. Coupled Vortex-Lattice Flight Dynamic Model with Aeroelastic Finite-Element Model of Flexible Wing Transport Aircraft with Variable Camber Continuous Trailing Edge Flap for Drag Reduction

    Science.gov (United States)

    Nguyen, Nhan; Ting, Eric; Nguyen, Daniel; Dao, Tung; Trinh, Khanh

    2013-01-01

    This paper presents a coupled vortex-lattice flight dynamic model with an aeroelastic finite-element model to predict dynamic characteristics of a flexible wing transport aircraft. The aircraft model is based on NASA Generic Transport Model (GTM) with representative mass and stiffness properties to achieve a wing tip deflection about twice that of a conventional transport aircraft (10% versus 5%). This flexible wing transport aircraft is referred to as an Elastically Shaped Aircraft Concept (ESAC) which is equipped with a Variable Camber Continuous Trailing Edge Flap (VCCTEF) system for active wing shaping control for drag reduction. A vortex-lattice aerodynamic model of the ESAC is developed and is coupled with an aeroelastic finite-element model via an automated geometry modeler. This coupled model is used to compute static and dynamic aeroelastic solutions. The deflection information from the finite-element model and the vortex-lattice model is used to compute unsteady contributions to the aerodynamic force and moment coefficients. A coupled aeroelastic-longitudinal flight dynamic model is developed by coupling the finite-element model with the rigid-body flight dynamic model of the GTM.

  10. Wind-tunnel free-flight investigation of a 0.15-scale model of the F-106B airplane with vortex flaps

    Science.gov (United States)

    Yip, Long P.

    1987-01-01

    An investigation to determine the effects of vortex flaps on the flight dynamic characteristics of the F-106B in the area of low-speed, high-angle-of-attack flight was undertaken on a 0.15-scale model of the airplane in the Langley 30- by 60-Foot Tunnel. Static force tests, dynamic forced-oscillation tests, as well as free-flight tests were conducted to obtain a data base on the flight characteristics of the F-106B airplane with vortex flaps. Vortex flap configurations tested included a full-span gothic flap, a full-span constant-chord flap, and a part-span gothic flap.

  11. A sensory-motor control model of animal flight explains why bats fly differently in light versus dark.

    Directory of Open Access Journals (Sweden)

    Nadav S Bar

    2015-01-01

    Full Text Available Animal flight requires fine motor control. However, it is unknown how flying animals rapidly transform noisy sensory information into adequate motor commands. Here we developed a sensorimotor control model that explains vertebrate flight guidance with high fidelity. This simple model accurately reconstructed complex trajectories of bats flying in the dark. The model implies that in order to apply appropriate motor commands, bats have to estimate not only the angle-to-target, as was previously assumed, but also the angular velocity ("proportional-derivative" controller. Next, we conducted experiments in which bats flew in light conditions. When using vision, bats altered their movements, reducing the flight curvature. This change was explained by the model via reduction in sensory noise under vision versus pure echolocation. These results imply a surprising link between sensory noise and movement dynamics. We propose that this sensory-motor link is fundamental to motion control in rapidly moving animals under different sensory conditions, on land, sea, or air.

  12. Application of GIS-based models for delineating the UAV flight region to support Search and Rescue activities

    Science.gov (United States)

    Jurecka, Miroslawa; Niedzielski, Tomasz

    2017-04-01

    The objective of the approach presented in this paper is to demonstrate a potential of using the combination of two GIS-based models - mobility model and ring model - for delineating a region above which an Unmanned Aerial Vehicle (UAV) should fly to support the Search and Rescue (SAR) activities. The procedure is based on two concepts, both describing a possible distance/path that lost person could travel from the initial planning point (being either the point last seen, or point last known). The first approach (the ring model) takes into account the crow's flight distance traveled by a lost person and its probability distribution. The second concept (the mobility model) is based on the estimated travel speed and the associated features of the geographical environment of the search area. In contrast to the ring model covering global (hence more general) SAR perspective, the mobility model represents regional viewpoint by taking into consideration local impedance. Both models working together can serve well as a starting point for the UAV flight planning to strengthen the SAR procedures. We present the method of combining the two above-mentioned models in order to delineate UAVs flight region and increase the Probability of Success for future SAR missions. The procedure is a part of a larger Search and Rescue (SAR) system which is being developed at the University of Wrocław, Poland (research project no. IP2014 032773 financed by the Ministry of Science and Higher Education of Poland). The mobility and ring models have been applied to the Polish territory, and they act in concert to provide the UAV operator with the optimal search region. This is attained in real time so that the UAV-based SAR mission can be initiated quickly.

  13. High-precision cryogenic wheel mechanisms of the JWST/MIRI instrument: performance of the flight models

    Science.gov (United States)

    Krause, O.; Müller, F.; Birkmann, S.; Böhm, A.; Ebert, M.; Grözinger, U.; Henning, Th.; Hofferbert, R.; Huber, A.; Lemke, D.; Rohloff, R.-R.; Scheithauer, S.; Gross, T.; Fischer, T.; Luichtel, G.; Merkle, H.; Übele, M.; Wieland, H.-U.; Amiaux, J.; Jager, R.; Glauser, A.; Parr-Burman, P.; Sykes, J.

    2010-07-01

    The Mid Infrared Instrument (MIRI) aboard JWST is equipped with one filter wheel and two dichroic-grating wheel mechanisms to reconfigure the instrument between observing modes such as broad/narrow-band imaging, coronagraphy and low/medium resolution spectroscopy. Key requirements for the three mechanisms with up to 18 optical elements on the wheel include: (1) reliable operation at T = 7 K, (2) high positional accuracy of 4 arcsec, (3) low power dissipation, (4) high vibration capability, (5) functionality at 7 K ball bearing, a central torque motor for actuation, a ratchet system with monolithic CuBe flexural pivots for precise and powerless positioning and a magnetoresistive position sensor has been implemented. We report here the final performance and lessons-learnt from the successful acceptance test program of the MIRI wheel mechanism flight models. The mechanisms have been meanwhile integrated into the flight model of the MIRI instrument, ready for launch in 2014 by an Ariane 5 rocket.

  14. Simulation Evaluation of Pilot Inputs for Real Time Modeling During Commercial Flight Operations

    Science.gov (United States)

    Martos, Borja; Ranaudo, Richard; Oltman, Ryan; Myhre, Nick

    2017-01-01

    Aircraft dynamics characteristics can only be identified from flight data when the aircraft dynamics are excited sufficiently. A preliminary study was conducted into what types and levels of manual piloted control excitation would be required for accurate Real-Time Parameter IDentification (RTPID) results by commercial airline pilots. This includes assessing the practicality for the pilot to provide this excitation when cued, and to further understand if pilot inputs during various phases of flight provide sufficient excitation naturally. An operationally representative task was evaluated by 5 commercial airline pilots using the NASA Ice Contamination Effects Flight Training Device (ICEFTD). Results showed that it is practical to use manual pilot inputs only as a means of achieving good RTPID in all phases of flight and in flight turbulence conditions. All pilots were effective in satisfying excitation requirements when cued. Much of the time, cueing was not even necessary, as just performing the required task provided enough excitation for accurate RTPID estimation. Pilot opinion surveys reported that the additional control inputs required when prompted by the excitation cueing were easy to make, quickly mastered, and required minimal training.

  15. Vortex-wake interactions of a flapping foil that models animal swimming and flight.

    Science.gov (United States)

    Lentink, David; Muijres, Florian T; Donker-Duyvis, Frits J; van Leeuwen, Johan L

    2008-01-01

    The fluid dynamics of many swimming and flying animals involves the generation and shedding of vortices into the wake. Here we studied the dynamics of similar vortices shed by a simple two-dimensional flapping foil in a soap-film tunnel. The flapping foil models an animal wing, fin or tail in forward locomotion. The vortical flow induced by the foil is correlated to (the resulting) thickness variations in the soap film. We visualized these thickness variations through light diffraction and recorded it with a digital high speed camera. This set-up enabled us to study the influence of foil kinematics on vortex-wake interactions. We varied the dimensionless wavelength of the foil (lambda*=4-24) at a constant dimensionless flapping amplitude (A*=1.5) and geometric angle of attack amplitude (A(alpha,geo)=15 degrees ). The corresponding Reynolds number was of the order of 1000. Such values are relevant for animal swimming and flight. We found that a significant leading edge vortex (LEV) was generated by the foil at low dimensionless wavelengths (lambda*wake dynamics evolved from a wavy von Kármán-like vortex wake shed along the sinusoidal path of the foil into a wake densely packed with large interacting vortices. We found that strongly interacting vortices could change the wake topology abruptly. This occurred when vortices were close enough to merge or tear each other apart. Our experiments show that relatively small changes in the kinematics of a flapping foil can alter the topology of the vortex wake drastically.

  16. Pitch Controllability Based on Airplane Model without Short-Period Approximation—Flight Simulator Experiment—

    Science.gov (United States)

    Sato, Osamu; Kobayashi, Osamu

    Pitch controllability of an airplane is very important for longitudinal flying qualities, therefore, much research has been conducted. However, it has not been clarified why pitch handling qualities degrades in the low speed, e.g. take-off and landing flight phases. On this topic, this paper investigates the effect of several parameters of the short-period mode and phugoid mode using a flight simulator. The results show the following conclusions: The difference between the initial phase angles in two modal components in the pitch attitude response to elevator step input plays the most important role in the pitch handling qualities among modal parameters; and the difference of the two modal natural frequencies has small effect on the pitch controllability even when flight speed decreases.

  17. 76 FR 26949 - Special Conditions: Boeing Model 747-8 Series Airplanes; Overhead Flight Attendant Rest Compartment

    Science.gov (United States)

    2011-05-10

    ...; Overhead Flight Attendant Rest Compartment AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... installation of an overhead flight attendant rest compartment. The applicable airworthiness regulations do not... installing an overhead flight attendant rest (OFAR) compartment creates a smaller compartment volume...

  18. S-2 stage 1/25 scale model base region thermal environment test. Volume 1: Test results, comparison with theory and flight data

    Science.gov (United States)

    Sadunas, J. A.; French, E. P.; Sexton, H.

    1973-01-01

    A 1/25 scale model S-2 stage base region thermal environment test is presented. Analytical results are included which reflect the effect of engine operating conditions, model scale, turbo-pump exhaust gas injection on base region thermal environment. Comparisons are made between full scale flight data, model test data, and analytical results. The report is prepared in two volumes. The description of analytical predictions and comparisons with flight data are presented. Tabulation of the test data is provided.

  19. Lift calculations based on accepted wake models for animal flight are inconsistent and sensitive to vortex dynamics.

    Science.gov (United States)

    Gutierrez, Eric; Quinn, Daniel B; Chin, Diana D; Lentink, David

    2016-12-06

    There are three common methods for calculating the lift generated by a flying animal based on the measured airflow in the wake. However, these methods might not be accurate according to computational and robot-based studies of flapping wings. Here we test this hypothesis for the first time for a slowly flying Pacific parrotlet in still air using stereo particle image velocimetry recorded at 1000 Hz. The bird was trained to fly between two perches through a laser sheet wearing laser safety goggles. We found that the wingtip vortices generated during mid-downstroke advected down and broke up quickly, contradicting the frozen turbulence hypothesis typically assumed in animal flight experiments. The quasi-steady lift at mid-downstroke was estimated based on the velocity field by applying the widely used Kutta-Joukowski theorem, vortex ring model, and actuator disk model. The calculated lift was found to be sensitive to the applied model and its different parameters, including vortex span and distance between the bird and laser sheet-rendering these three accepted ways of calculating weight support inconsistent. The three models predict different aerodynamic force values mid-downstroke compared to independent direct measurements with an aerodynamic force platform that we had available for the same species flying over a similar distance. Whereas the lift predictions of the Kutta-Joukowski theorem and the vortex ring model stayed relatively constant despite vortex breakdown, their values were too low. In contrast, the actuator disk model predicted lift reasonably accurately before vortex breakdown, but predicted almost no lift during and after vortex breakdown. Some of these limitations might be better understood, and partially reconciled, if future animal flight studies report lift calculations based on all three quasi-steady lift models instead. This would also enable much needed meta studies of animal flight to derive bioinspired design principles for quasi-steady lift

  20. How High? How Fast? How Long? Modeling Water Rocket Flight with Calculus

    Science.gov (United States)

    Ashline, George; Ellis-Monaghan, Joanna

    2006-01-01

    We describe an easy and fun project using water rockets to demonstrate applications of single variable calculus concepts. We provide procedures and a supplies list for launching and videotaping a water rocket flight to provide the experimental data. Because of factors such as fuel expulsion and wind effects, the water rocket does not follow the…

  1. How High? How Fast? How Long? Modeling Water Rocket Flight with Calculus

    Science.gov (United States)

    Ashline, George; Ellis-Monaghan, Joanna

    2006-01-01

    We describe an easy and fun project using water rockets to demonstrate applications of single variable calculus concepts. We provide procedures and a supplies list for launching and videotaping a water rocket flight to provide the experimental data. Because of factors such as fuel expulsion and wind effects, the water rocket does not follow the…

  2. Perception model analysis of flight simulator motion for a decrab maneuver

    NARCIS (Netherlands)

    Groen, E.L.; Smaïli, M.H.; Hosman, R.J.A.W.

    2007-01-01

    In this flight simulator study, eleven pilots rated their motion perception during a series of decrab maneuvers of a twin-engine passenger aircraft. Simulator yaw, sway, and roll motion were varied independently to examine their relative contribution to the pilots’ judgments. In one set of condition

  3. Development of Autonomous Unmanned Aerial Vehicle Platform: Modeling, Simulating, and Flight Testing

    Science.gov (United States)

    2006-03-01

    Shin-Ichiro Higashino of the Universities of Washington, Seattle, and Kyushu, Japan respectively. In 2003, Ly and Higashino conducted research similar...of Technology, MA. September 2004. Ly, L. and Higashino , S. “Development of a UAV-Flight Test Vehicle at the University of Washington.” Presented

  4. ExFiT Flight Design and Structural Modeling for FalconLAUNCH VIII Sounding Rocket

    Science.gov (United States)

    2010-03-01

    in October of 1958[13]. In 1963, the first lifting body flight test was conducted with NASA’s M2-F1, nick - named “the flying bathtub” shown in Figure...missiles. Technical Report NACA TN 4197, NACA. 21. Hodges , D., and Pierce, A., 2002. An Introduction to Structural Dynamics and Aeroelasticity John

  5. Modeling and Simulation Technology A New Vector for Flight-Test

    Science.gov (United States)

    1998-06-01

    control system failure also reminds us that further improvement in the design of the F-22’s digital flight control systems is Notes 37 Charles W. Brown...third the number of software applications in use today will be here in another fifteen years.63 Cristoph W. Klomp, who leads Boeing’s 737 software office

  6. Coupled simulation of CFD-flight-mechanics with a two-species-gas-model for the hot rocket staging

    Science.gov (United States)

    Li, Yi; Reimann, Bodo; Eggers, Thino

    2016-11-01

    The hot rocket staging is to separate the lowest stage by directly ignite the continuing-stage-motor. During the hot staging, the rocket stages move in a harsh dynamic environment. In this work, the hot staging dynamics of a multistage rocket is studied using the coupled simulation of Computational Fluid Dynamics and Flight Mechanics. Plume modeling is crucial for a coupled simulation with high fidelity. A 2-species-gas model is proposed to simulate the flow system of the rocket during the staging: the free-stream is modeled as "cold air" and the exhausted plume from the continuing-stage-motor is modeled with an equivalent calorically-perfect-gas that approximates the properties of the plume at the nozzle exit. This gas model can well comprise between the computation accuracy and efficiency. In the coupled simulations, the Navier-Stokes equations are time-accurately solved in moving system, with which the Flight Mechanics equations can be fully coupled. The Chimera mesh technique is utilized to deal with the relative motions of the separated stages. A few representative staging cases with different initial flight conditions of the rocket are studied with the coupled simulation. The torque led by the plume-induced-flow-separation at the aft-wall of the continuing-stage is captured during the staging, which can assist the design of the controller of the rocket. With the increasing of the initial angle-of-attack of the rocket, the staging quality becomes evidently poorer, but the separated stages are generally stable when the initial angle-of-attack of the rocket is small.

  7. LFI 30 and 44 GHz receivers Back-End Modules

    Energy Technology Data Exchange (ETDEWEB)

    Artal, E; Aja, B; Fuente, M L de la; Pascual, J P; Mediavilla, A [Dpt. Ingenieria de Comunicaciones, Universidad de Cantabria, Plaza de la Ciencia, 39005 Santander (Spain); Martinez-Gonzalez, E [Instituto de Fisica de Cantabria, CSIC-Universidad de Cantabria, Avda. de los Castros s/n, 39005 Santander (Spain); Pradell, L; Paco, P de [Departament de Teoria del Senyal i Comunicacions, Universitat Politecnica de Catalunya, Barcelona (Spain); Bara, M; Blanco, E; GarcIa, E [Mier Comunicaciones S.A. La Garriga, Barcelona (Spain); Davis, R; Kettle, D; Roddis, N; Wilkinson, A [Jodrell Bank Centre for Astrophysics, University of Manchester, Manchester (United Kingdom); Bersanelli, M; Mennella, A; Tomasi, M [Universita degli studi di Milano, Department of Physics Via Celoria 16, Milano (Italy); Butler, R C; Cuttaia, F, E-mail: artale@unican.e [INAF/IASF - Bologna Via P. Gobetti 101, 40129 Bologna (Italy)

    2009-12-15

    The 30 and 44 GHz Back End Modules (BEM) for the Planck Low Frequency Instrument are broadband receivers (20% relative bandwidth) working at room temperature. The signals coming from the Front End Module are amplified, band pass filtered and finally converted to DC by a detector diode. Each receiver has two identical branches following the differential scheme of the Planck radiometers. The BEM design is based on MMIC Low Noise Amplifiers using GaAs P-HEMT devices, microstrip filters and Schottky diode detectors. Their manufacturing development has included elegant breadboard prototypes and finally qualification and flight model units. Electrical, mechanical and environmental tests were carried out for the characterization and verification of the manufactured BEMs. A description of the 30 and 44 GHz Back End Modules of Planck-LFI radiometers is given, with details of the tests done to determine their electrical and environmental performances. The electrical performances of the 30 and 44 GHz Back End Modules: frequency response, effective bandwidth, equivalent noise temperature, 1/f noise and linearity are presented.

  8. Modified panel data regression model and its applications to the airline industry: Modeling the load factor of Europe North and Europe Mid Atlantic flights

    Directory of Open Access Journals (Sweden)

    Yohannes Yebabe Tesfay

    2016-08-01

    Full Text Available This article conducts a stochastic analysis on the passenger load factor of the airline industry. Used to measure competence and performance of the airline, load factor is the percentage of seats filled by revenue passengers. It is considered a complex metric in the airline industry. Thus, it is affected by several dynamic factors. This paper applies advanced stochastic models to obtain the best fitted trend of load factor for Europe's North Atlantic (NA and Mid Atlantic (MA flights in the Association of European Airlines. The stochastic model's fit helps to forecast the load factor of flights within these geographical regions and evaluate the airline's demand and capacity management. The paper applies spectral density estimation and dynamic time effects panel data regression models on the monthly load factor flights of NA and MA from 1991 to 2013. The results show that the load factor has both periodic and serial correlations. Consequently, the author acknowledges that the use of an ordinal panel data model is inappropriate for a realistic econometric model of load factor. Therefore, to control the periodic correlation structure, the author modified the existing model was modified by introducing dynamic time effects. Moreover, to eradicate serial correlation, the author applied the Prais–Winsten methodology was applied to fit the model. In this econometric analysis, the study finds that AEA airlines have greater demand and capacity management for both NA and MA flights. In conclusion, this study prosperous in finding an effective and efficient dynamic time effects panel data regression model fit, which empowers engineers to forecast the load factor off AEA airlines.

  9. Understanding metabolic alterations in space flight using quantitative models: fluid and energy balance

    Science.gov (United States)

    Leonard, J. I.

    1986-01-01

    This report summarizes many of the results obtained during the Skylab program, on metabolic changes during weightlessness. The examination of the data was conducted following an integrated multi-disciplinary and multi-experimental approach. Emphasis is given on several major aspects of metabolic adaptation to space flight: fluid-electrolyte regulation, mechanisms of hormone disturbances, energy balance and etiology of weight loss. The aim is to obtain a composite picture of the fluid, electrolyte and energy response to weightlessness.

  10. Understanding metabolic alterations in space flight using quantitative models. Fluid and energy balance

    Science.gov (United States)

    Leonard, Joel I.

    This report summarizes many of the results obtained during the Skylab program, on metabolic changes during weightlessness. The examination of the data was conducted following an integrated multi-disciplinary and multi-experimental approach. Emphasis is given on several major aspects of metabolic adaptation to space flight: fluid-electrolyte regulation, mechanisms of hormone disturbances, energy balance and etiology of weight loss. The aim is to obtain a composite picture of the fluid, electrolyte and energy response to weightlessness.

  11. Modeling the Fault Tolerant Capability of a Flight Control System: An Exercise in SCR Specification

    Science.gov (United States)

    Alexander, Chris; Cortellessa, Vittorio; DelGobbo, Diego; Mili, Ali; Napolitano, Marcello

    2000-01-01

    In life-critical and mission-critical applications, it is important to make provisions for a wide range of contingencies, by providing means for fault tolerance. In this paper, we discuss the specification of a flight control system that is fault tolerant with respect to sensor faults. Redundancy is provided by analytical relations that hold between sensor readings; depending on the conditions, this redundancy can be used to detect, identify and accommodate sensor faults.

  12. Design and Evaluation of a Dynamic Programming Flight Routing Algorithm Using the Convective Weather Avoidance Model

    Science.gov (United States)

    Ng, Hok K.; Grabbe, Shon; Mukherjee, Avijit

    2010-01-01

    The optimization of traffic flows in congested airspace with varying convective weather is a challenging problem. One approach is to generate shortest routes between origins and destinations while meeting airspace capacity constraint in the presence of uncertainties, such as weather and airspace demand. This study focuses on development of an optimal flight path search algorithm that optimizes national airspace system throughput and efficiency in the presence of uncertainties. The algorithm is based on dynamic programming and utilizes the predicted probability that an aircraft will deviate around convective weather. It is shown that the running time of the algorithm increases linearly with the total number of links between all stages. The optimal routes minimize a combination of fuel cost and expected cost of route deviation due to convective weather. They are considered as alternatives to the set of coded departure routes which are predefined by FAA to reroute pre-departure flights around weather or air traffic constraints. A formula, which calculates predicted probability of deviation from a given flight path, is also derived. The predicted probability of deviation is calculated for all path candidates. Routes with the best probability are selected as optimal. The predicted probability of deviation serves as a computable measure of reliability in pre-departure rerouting. The algorithm can also be extended to automatically adjust its design parameters to satisfy the desired level of reliability.

  13. Performance Testing of the Astro-H Flight Model 3-stage ADR

    Science.gov (United States)

    Shirron, Peter J.; Kimball, Mark O.; DiPirro, Michael J.; Bialas, Thomas G.

    The Soft X-ray Spectrometer (SXS) is one of four instruments that will be flown on the Japanese Astro-H satellite, planned for launch in late 2015/early 2016. The SXS will perform imaging spectroscopy in the soft x-ray band using a 6x6 array of silicon microcalorimeters operated at 50 mK, cooled by an adiabatic demagnetization refrigerator (ADR). NASA/GSFC is providing the detector array and ADR, and Sumitomo Heavy Industries, Inc. is providing the remainder of the cryogenic system (superfluid helium dewar (cryocoolers and a 4.5 K Joule-Thomson (JT) cryocooler). The ADR is unique in that it is designed to use both the liquid helium and the JT cryocooler as it heat sink. The flight detector and ADR assembly have successfully undergone vibration and performance testing at GSFC, and have now undergone initial performance testing with the flight dewar at Sumitomo Heavy Industries, Inc. in Japan. This paper summaries the performance of the flight ADR in both cryogen-based and cryogen-free operating modes.

  14. A Risk Assessment Model for Reduced Aircraft Separation: A Quantitative Method to Evaluate the Safety of Free Flight

    Science.gov (United States)

    Cassell, Rick; Smith, Alex; Connors, Mary; Wojciech, Jack; Rosekind, Mark R. (Technical Monitor)

    1996-01-01

    As new technologies and procedures are introduced into the National Airspace System, whether they are intended to improve efficiency, capacity, or safety level, the quantification of potential changes in safety levels is of vital concern. Applications of technology can improve safety levels and allow the reduction of separation standards. An excellent example is the Precision Runway Monitor (PRM). By taking advantage of the surveillance and display advances of PRM, airports can run instrument parallel approaches to runways separated by 3400 feet with the same level of safety as parallel approaches to runways separated by 4300 feet using the standard technology. Despite a wealth of information from flight operations and testing programs, there is no readily quantifiable relationship between numerical safety levels and the separation standards that apply to aircraft on final approach. This paper presents a modeling approach to quantify the risk associated with reducing separation on final approach. Reducing aircraft separation, both laterally and longitudinally, has been the goal of several aviation R&D programs over the past several years. Many of these programs have focused on technological solutions to improve navigation accuracy, surveillance accuracy, aircraft situational awareness, controller situational awareness, and other technical and operational factors that are vital to maintaining flight safety. The risk assessment model relates different types of potential aircraft accidents and incidents and their contribution to overall accident risk. The framework links accident risks to a hierarchy of failsafe mechanisms characterized by procedures and interventions. The model will be used to assess the overall level of safety associated with reducing separation standards and the introduction of new technology and procedures, as envisaged under the Free Flight concept. The model framework can be applied to various aircraft scenarios, including parallel and in

  15. Aircraft automatic-flight-control system with inversion of the model in the feed-forward path using a Newton-Raphson technique for the inversion

    Science.gov (United States)

    Smith, G. A.; Meyer, G.; Nordstrom, M.

    1986-01-01

    A new automatic flight control system concept suitable for aircraft with highly nonlinear aerodynamic and propulsion characteristics and which must operate over a wide flight envelope was investigated. This exact model follower inverts a complete nonlinear model of the aircraft as part of the feed-forward path. The inversion is accomplished by a Newton-Raphson trim of the model at each digital computer cycle time of 0.05 seconds. The combination of the inverse model and the actual aircraft in the feed-forward path alloys the translational and rotational regulators in the feedback path to be easily designed by linear methods. An explanation of the model inversion procedure is presented. An extensive set of simulation data for essentially the full flight envelope for a vertical attitude takeoff and landing aircraft (VATOL) is presented. These data demonstrate the successful, smooth, and precise control that can be achieved with this concept. The trajectory includes conventional flight from 200 to 900 ft/sec with path accelerations and decelerations, altitude changes of over 6000 ft and 2g and 3g turns. Vertical attitude maneuvering as a tail sitter along all axes is demonstrated. A transition trajectory from 200 ft/sec in conventional flight to stationary hover in the vertical attitude includes satisfactory operation through lift-cure slope reversal as attitude goes from horizontal to vertical at constant altitude. A vertical attitude takeoff from stationary hover to conventional flight is also demonstrated.

  16. Flapping Wings of an Inclined Stroke Angle: Experiments and Reduced-Order Models in Dual Aerial/Aquatic Flight

    Science.gov (United States)

    Izraelevitz, Jacob; Triantafyllou, Michael

    2016-11-01

    Flapping wings in nature demonstrate a large force actuation envelope, with capabilities beyond the limits of static airfoil section coefficients. Puffins, guillemots, and other auks particularly showcase this mechanism, as they are able to both generate both enough thrust to swim and lift to fly, using the same wing, by changing the wing motion trajectory. The wing trajectory is therefore an additional design criterion to be optimized along with traditional aircraft parameters, and could possibly enable dual aerial/aquatic flight. We showcase finite aspect-ratio flapping wing experiments, dynamic similarity arguments, and reduced-order models for predicting the performance of flapping wings that carry out complex motion trajectories.

  17. Tests Results of the Electrostatic Accelerometer Flight Models for Gravity Recovery and Climate Experiment Follow-On Mission (GRACE FO)

    Science.gov (United States)

    Perrot, E.; Boulanger, D.; Christophe, B.; Foulon, B.; Lebat, V.; Huynh, P. A.; Liorzou, F.

    2015-12-01

    The GRACE FO mission, led by the JPL (Jet Propulsion Laboratory), is an Earth-orbiting gravity mission, continuation of the GRACE mission, which will produce an accurate model of the Earth's gravity field variation providing global climatic data during five years at least. The mission involves two satellites in a loosely controlled tandem formation, with a micro-wave link measuring the inter-satellites distance variation. Earth's mass distribution non-uniformities cause variations of the inter-satellite distance. This variation is measured to recover gravity, after subtracting the non-gravitational contributors, as the residual drag. ONERA (the French Aerospace Lab) is developing, manufacturing and testing electrostatic accelerometers measuring this residual drag applied on the satellites. The accelerometer is composed of two main parts: the Sensor Unit (including the Sensor Unit Mechanics - SUM - and the Front-End Electronic Unit - FEEU) and the Interface Control Unit - ICU. In the Accelerometer Core, located in the Sensor Unit Mechanics, the proof mass is levitated and maintained at the center of an electrode cage by electrostatic forces. Thus, any drag acceleration applied on the satellite involves a variation on the servo-controlled electrostatic suspension of the mass. The voltage on the electrodes providing this electrostatic force is the output measurement of the accelerometer. The impact of the accelerometer defaults (geometry, electronic and parasitic forces) leads to bias, misalignment and scale factor error, non-linearity and noise. Some of these accelerometer defaults are characterized by tests with micro-gravity pendulum bench on ground and with drops in ZARM catapult. The Critical Design Review was achieved successfully on September 2014. The Engineering Model (EM) was integrated and tested successfully, with ground levitation, drops, Electromagnetic Compatibility and thermal vacuum. The integration of the two Flight Models was done on July 2015. The

  18. Description, validation, and modification of the Guyton model for space-flight applications. Part A. Guyton model of circulatory, fluid and electrolyte control. Part B. Modification of the Guyton model for circulatory, fluid and electrolyte control

    Science.gov (United States)

    Leonard, J. I.

    1985-01-01

    The mathematical model that has been a cornerstone for the systems analysis of space-flight physiological studies is the Guyton model describing circulatory, fluid and electrolyte regulation. The model and the modifications that are made to permit simulation and analysis of the stress of weightlessness are described.

  19. Modeling the adoption process of the Flight Training Synthetic Environment Technology (FTSET) in the Turkish Army Aviation (TUAA)

    OpenAIRE

    Boztas, Omer

    2006-01-01

    MBA Professional Report The motivation for using Flight Training Synthetic Environment Technology (FTSET) in military aviation is to create a cost-efficient and a risk-managed training environment. However, deciding on the appropriate mix of synthetic versus actual flight training remains a great unresolved issue. Further, FTSET usage and its adoption level may vary across the aviation community and flight training curricula. TUAA has employed FTSET in helicopter flight training since 1990...

  20. 77 FR 69569 - Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Flight Envelope Protection: Pitch and...

    Science.gov (United States)

    2012-11-20

    ...; Flight Envelope Protection: Pitch and Roll Limiting Functions AGENCY: Federal Aviation Administration... feature associated with pitch and roll limiting functions, specifically an electronic flight control... takeoff. The primary flight controls consist of hydraulically powered fly-by-wire elevators, aileron and...

  1. Overbooking Airline Flights.

    Science.gov (United States)

    Austin, Joe Dan

    1982-01-01

    The problems involved in making reservations for airline flights is discussed in creating a mathematical model designed to maximize an airline's income. One issue not considered in the model is any public relations problem the airline may have. The model does take into account the issue of denied boarding compensation. (MP)

  2. Overbooking Airline Flights.

    Science.gov (United States)

    Austin, Joe Dan

    1982-01-01

    The problems involved in making reservations for airline flights is discussed in creating a mathematical model designed to maximize an airline's income. One issue not considered in the model is any public relations problem the airline may have. The model does take into account the issue of denied boarding compensation. (MP)

  3. Degree-Day Prediction Models for the Flight Phenology of Western Bean Cutworm (Lepidoptera: Noctuidae) Assessed with the Concordance Correlation Coefficient.

    Science.gov (United States)

    Hanson, A A; Moon, R D; Wright, R J; Hunt, T E; Hutchison, W D

    2015-08-01

    Western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a native, univoltine pest of corn and dry beans in North America. The current degree-day model for predicting a specified percentage of yearly moth flight involves heat unit accumulation above 10°C after 1 May. However, because the moth's observed range has expanded into the northern and eastern United States, there is concern that suitable temperatures before May could allow for significant S. albicosta development. Daily blacklight moth catch and temperature data from four Nebraska locations were used to construct degree-day models using simple or sine-wave methods, starting dates between 1 January and 1 May, and lower (-5 to 15°C) and upper (20 to 43.3°C) developmental thresholds. Predicted dates of flight from these models were compared with observed flight dates using independent datasets to assess model performance. Model performance was assessed with the concordance correlation coefficient to concurrently evaluate precision and accuracy. The best model for predicting timing of S. albicosta flight used simple degree-day calculations beginning on 1 March, a 3.3°C (38°F) lower threshold, and a 23.9°C (75°F) upper threshold. The revised cumulative flight model indicated field scouting to estimate moth egg density at the time of 25% flight should begin when 1,432 degree-days (2,577 degree-days °F) have accumulated. These results underscore the importance of assessing multiple parameters in phenological models and utilizing appropriate assessment methods, which in this case may allow for improved timing of field scouting for S. albicosta.

  4. Miracle Flights

    Science.gov (United States)

    ... her future. Donate Now Make your donation today Saving Lives One Flight At A ... “To improve access to health care by providing financial assistance to low income children for commercial air ...

  5. Hovering and targeting flight simulations of a dragonfly-like flapping wing-body model by the immersed boundary-lattice Boltzmann method

    Science.gov (United States)

    Hirohashi, Kensuke; Inamuro, Takaji

    2017-08-01

    Hovering and targeting flights of the dragonfly-like flapping wing-body model are numerically investigated by using the immersed boundary-lattice Boltzmann method. The governing parameters of the problem are the Reynolds number Re, the Froude number Fr, and the non-dimensional mass m. We set the parameters at Re = 200, Fr = 15 and m = 51. First, we simulate free flights of the model for various values of the phase difference angle ϕ between the forewing and the hindwing motions and for various values of the stroke angle β between the stroke plane and the horizontal plane. We find that the vertical motion of the model depends on the phase difference angle ϕ, and the horizontal motion of the model depends on the stroke angle β. Secondly, using the above results we try to simulate the hovering flight by dynamically changing the phase difference angle ϕ and the stroke angle β. The hovering flight can be successfully simulated by a simple proportional controller of the phase difference angle and the stroke angle. Finally, we simulate a targeting flight by dynamically changing the stroke angle β.

  6. A study on aerodynamics and mechanisms of elementary morphing models for flapping wing in bat forward flight

    CERN Document Server

    Zi-Wu, Guan

    2014-01-01

    The large active wing deformation is a significant way to generate high aerodynamic forces required in bat flapping flight. Besides the twisting, the elementary morphing models of a bat wing are proposed, such as wing-bending in the spanwise direction, wing-cambering in the chordwise direction, and wing area-changing. A plate of aspect ratio 3 is used to model a bat wing and a three dimensional unsteady panel method is applied to predict the aerodynamic forces. It is found that the cambering model has a great positive influence on the lift, followed by area-changing model and then the bending model. The further study indicates that the vortex control is a main mechanism to produce high aerodynamic forces, and the mechanisms for the aerodynamic force enhancement are the asymmetry of the cambered wing and the amplifier effects of wing area-changing and wing bending. The lift and thrust are mainly generated during the downstroke and almost negligible forces during the upstroke by the integrated morphing model-wi...

  7. A dynamic human water and electrolyte balance model for verification and optimization of life support systems in space flight applications

    Science.gov (United States)

    Hager, P.; Czupalla, M.; Walter, U.

    2010-11-01

    In this paper we report on the development of a dynamic MATLAB SIMULINK® model for the water and electrolyte balance inside the human body. This model is part of an environmentally sensitive dynamic human model for the optimization and verification of environmental control and life support systems (ECLSS) in space flight applications. An ECLSS provides all vital supplies for supporting human life on board a spacecraft. As human space flight today focuses on medium- to long-term missions, the strategy in ECLSS is shifting to closed loop systems. For these systems the dynamic stability and function over long duration are essential. However, the only evaluation and rating methods for ECLSS up to now are either expensive trial and error breadboarding strategies or static and semi-dynamic simulations. In order to overcome this mismatch the Exploration Group at Technische Universität München (TUM) is developing a dynamic environmental simulation, the "Virtual Habitat" (V-HAB). The central element of this simulation is the dynamic and environmentally sensitive human model. The water subsystem simulation of the human model discussed in this paper is of vital importance for the efficiency of possible ECLSS optimizations, as an over- or under-scaled water subsystem would have an adverse effect on the overall mass budget. On the other hand water has a pivotal role in the human organism. Water accounts for about 60% of the total body mass and is educt and product of numerous metabolic reactions. It is a transport medium for solutes and, due to its high evaporation enthalpy, provides the most potent medium for heat load dissipation. In a system engineering approach the human water balance was worked out by simulating the human body's subsystems and their interactions. The body fluids were assumed to reside in three compartments: blood plasma, interstitial fluid and intracellular fluid. In addition, the active and passive transport of water and solutes between those

  8. Mechatronic Design, Dynamic Modeling and Results of a Satellite Flight Simulator for Experimental Validation of Satellite Attitude Determination and Control Schemes in 3-Axis

    Directory of Open Access Journals (Sweden)

    M.A. Mendoza-Bárcenas

    2014-06-01

    Full Text Available This paper describes the integration and implementation of a satellite flight simulator based on an air bearing system, which was designed and instrumented in our laboratory to evaluate and to perform research in the field of Attitude Determination and Control Systems for satellites, using the hardware-in-the-loop technique. The satellite flight simulator considers two main blocks: an instrumented mobile platform and an external computer executing costume-made Matlab® software. The first block is an air bearing system containing an FPGA based on-board computer with capabilities to integrate digital architectures for data acquisition from inertial navigation sensors, control of actuators and communications data handling. The second block is an external personal computer, which runs in parallel Matlab® based algorithms for attitude determination and control. Both blocks are linked by means of radio modems. The paper also presents the analysis of the satellite flight simulator dynamics in order to obtain its movement equation which allows a better understanding of the satellite flight simulator behavior. In addition, the paper shows experimental results about the automated tracking of the satellite flight simulator based a virtual reality model developed in Matlab®. It also depicts two different versions of FPGA based on-board computers developed in-house to integrate embedded and polymorphic digital architectures for spacecrafts applications. Finally, the paper shows successful experimental results for an attitude control test using the satellite flight simulator based on a linear control law.

  9. Performance of the Clouds and the Earth's Radiant Energy System (CERES) Flight Model 5 (FM5) instrument on NPP mission

    Science.gov (United States)

    Thomas, Susan; Priestley, Kory J.; Hess, Phillip C.; Wilson, Robert S.; Smith, Nathaniel P.; Timcoe, Mark G.; Shankar, Mohan; Walikainen, Dale R.

    2012-09-01

    Clouds and the Earth's Radiant Energy System (CERES) instrument was designed to provide accurate measurements for the long-term monitoring of Earth's radiation energy budget. Flight Model 5, the sixth of the CERES instrument was launched aboard the NPP spacecraft on October 2011 and it has started the Earth-viewing measurements on January 26, 2012. The CERES instrument with the three scanning sensors measure radiances in 0.3 to 5.0 micron region with Shortwave sensor, 0.3 to elevation offset in the sensor measurement will be determined from the spacecraft pitch manuveur activity viewing the deep space. This paper covers the early-orbit checkout activities and the overall performance of the CERES-FM5 instrument. The postlaunch calibration and the validation results from the instrument are presented.

  10. Free flight simulations of a dragonfly-like flapping wing-body model using the immersed boundary-lattice Boltzmann method

    Energy Technology Data Exchange (ETDEWEB)

    Minami, Keisuke; Suzuki, Kosuke; Inamuro, Takaji, E-mail: inamuro@kuaero.kyoto-u.ac.jp [Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto 615-8540 (Japan)

    2015-02-01

    Free flights of the dragonfly-like flapping wing-body model are numerically investigated using the immersed boundary-lattice Boltzmann method. The governing parameters of the problem are the Reynolds number Re, the Froude number Fr, and the non-dimensional mass m, and we set the parameters at Re = 200, Fr = 15, and m = 51. First, we simulate free flights of the model without the pitching rotation for various values of the phase lag angle ϕ between the forewing and the hindwing motions. We find that the wing-body model goes forward in spite of ϕ, and the model with ϕ = 0{sup ∘} and 90{sup ∘} goes upward against gravity. The model with ϕ =180{sup ∘} goes almost horizontally, and the model with ϕ =270{sup ∘} goes downward. That is, the moving direction of the model depends on the phase lag angle ϕ. Secondly, we simulate free flights with the pitching rotation for various values of the phase lag angle ϕ. It is found that in spite of ϕ the wing-body model turns gradually in the nose-up direction and goes back and down as the pitching angle Θ{sub c} increases. That is, the wing-body model cannot make a stable forward flight without control. Finally, we show a way to control the pitching motion by changing the lead–lag angle γ(t). We propose a simple proportional controller of γ(t) which makes stable flights within Θ{sub c}=±5{sup ∘} and works well even for a large disturbance. (paper)

  11. Free flight simulations of a dragonfly-like flapping wing-body model using the immersed boundary-lattice Boltzmann method

    Science.gov (United States)

    Minami, Keisuke; Suzuki, Kosuke; Inamuro, Takaji

    2015-02-01

    Free flights of the dragonfly-like flapping wing-body model are numerically investigated using the immersed boundary-lattice Boltzmann method. The governing parameters of the problem are the Reynolds number Re, the Froude number Fr, and the non-dimensional mass m, and we set the parameters at Re = 200, Fr = 15, and m = 51. First, we simulate free flights of the model without the pitching rotation for various values of the phase lag angle ϕ between the forewing and the hindwing motions. We find that the wing-body model goes forward in spite of ϕ, and the model with φ = 0{}^\\circ and 90{}^\\circ goes upward against gravity. The model with φ =180{}^\\circ goes almost horizontally, and the model with φ =270{}^\\circ goes downward. That is, the moving direction of the model depends on the phase lag angle ϕ. Secondly, we simulate free flights with the pitching rotation for various values of the phase lag angle ϕ. It is found that in spite of ϕ the wing-body model turns gradually in the nose-up direction and goes back and down as the pitching angle {{\\Theta }c} increases. That is, the wing-body model cannot make a stable forward flight without control. Finally, we show a way to control the pitching motion by changing the lead-lag angle γ (t). We propose a simple proportional controller of γ (t) which makes stable flights within {{\\Theta }c}=+/- 5{}^\\circ and works well even for a large disturbance.

  12. Forward flight of a model butterfly: Simulation by equations of motion coupled with the Navier-Stokes equations

    Institute of Scientific and Technical Information of China (English)

    Hua Huang; Mao Sun

    2012-01-01

    The forward flight of a model butterfly was studied by simulation using the equations of motion coupled with the Navier-Stokes equations.The model butterfly moved under the action of aerodynamic and gravitational forces,where the aerodynamic forces were generated by flapping wings which moved with the body,allowing the body oscillations of the model butterfly to be simulated.The main results are as follows: (1) The aerodynamic force produced by the wings is approximately perpendicular to the long-axis of body and is much larger in the downstroke than in the upstroke.In the downstroke the body pitch angle is small and the large aerodynamic force points up and slightly backward,giving the weight-supporting vertical force and a small negative horizontal force,whilst in the upstroke,the body angle is large and the relatively small aerodynamic force points forward and slightly downward,giving a positive horizontal force which overcomes the body drag and the negative horizontal force generated in the downstroke.(2) Pitching oscillation of the butterfly body plays an equivalent role of the wing-rotation of many other insects.(3) The body-massspecific power of the model butterfly is 33.3 W/kg,not very different from that of many other insects,e.g.,fruitflies and dragonflies.

  13. Hovering and Transition Flight Tests of a 1/5-Scale Model of a Jet-Powered Vertical-Attitude VTOL Research Airplane

    Science.gov (United States)

    Smith, Charles C., Jr.

    1961-01-01

    An experimental investigation has been made to determine the dynamic stability and control characteristics of a 1/5-scale flying model of a jet-powered vertical-attitude VTOL research airplane in hovering and transition flight. The model was powered with either a hydrogen peroxide rocket motor or a compressed-air jet exhausting through an ejector tube to simulate the turbojet engine of the airplane. The gyroscopic effects of the engine were simulated by a flywheel driven by compressed-air jets. In hovering flight the model was controlled by jet-reaction controls which consisted of a swiveling nozzle on the main jet and a movable nozzle on each wing tip; and in forward flight the model was controlled by elevons and a rudder. If the gyroscopic effects of the jet engine were not represented, the model could be flown satisfactorily in hovering flight without any automatic stabilization devices. When the gyroscopic effects of the jet engine were represented, however, the model could not be controlled without the aid of artificial stabilizing devices because of the gyroscopic coupling of the yawing and pitching motions. The use of pitch and yaw dampers made these motions completely stable and the model could then be controlled very easily. In the transition flight tests, which were performed only with the automatic pitch and yaw dampers operating, it was found that the transition was very easy to perform either with or without the engine gyroscopic effects simulated, although the model had a tendency to fly in a rolled and sideslipped attitude at angles of attack between approximately 25 deg and 45 deg because of static directional instability in this range.

  14. Mars Organic Molecule Analyzer (MOMA) Mass Spectrometer Flight Model and Future Ion Trap-Based Planetary Instruments

    Science.gov (United States)

    Brinckerhoff, W. B.; van Amerom, F. H. W.; Danell, R.; Pinnick, V. T.; Arevalo, R. D., Jr.; Li, X.; Grubisic, A.; Getty, S.; Hovmand, L.; Mahaffy, P. R.

    2015-12-01

    The Mars Organic Molecule Analyzer (MOMA) investigation on the 2018 ExoMars rover will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from radiative and oxidative degradation. MOMA combines pyrolysis gas chromatography mass spectrometry (GCMS) of bulk powder samples and Mars ambient laser desorption mass spectrometry (LDMS) surface analysis, using a single ion trap MS. This dual source design enables MOMA to detect compounds over a wide range of molecular weights and volatilities. The structure of any detected organics may be further examined using MOMA's tandem mass spectrometry (MS/MS) mode. The flight model (FM) ion trap sensor and electronics have been assembled under the extremely clean and sterile conditions required by ExoMars, and have met or exceeded all performance specifications during initial functional tests. After Mars ambient thermal cycling and calibration, the FM will be delivered as a subsystem of MOMA to rover integration in mid-2016. There MOMA will join complementary rover instruments such as the Raman and MicrOmega spectrometers designed to analyze common drill samples. Following the MOMA design, linear ion trap mass spectrometer (LITMS)-based instruments are under development for future missions. LITMS adds enhanced capabilities such as precision (point-by-point) analysis of drill cores, negative ion detection, a wider mass range, and higher temperature pyrolysis with precision evolved gas analysis, while remaining highly compact and robust. Each of the capabilities of LITMS has been demonstrated on breadboard hardware. The next phase will realize an end-to-end brassboard at flight scale that will meet stringent technology readiness level (TRL) 6 criteria, indicating readiness for development toward missions to Mars, comets, asteroids, outer solar system moons, and beyond.

  15. Toward a Model-Based Approach for Flight System Fault Protection

    Science.gov (United States)

    Day, John; Meakin, Peter; Murray, Alex

    2012-01-01

    Use SysML/UML to describe the physical structure of the system This part of the model would be shared with other teams - FS Systems Engineering, Planning & Execution, V&V, Operations, etc., in an integrated model-based engineering environment Use the UML Profile mechanism, defining Stereotypes to precisely express the concepts of the FP domain This extends the UML/SysML languages to contain our FP concepts Use UML/SysML, along with our profile, to capture FP concepts and relationships in the model Generate typical FP engineering products (the FMECA, Fault Tree, MRD, V&V Matrices)

  16. Toward a Model-Based Approach for Flight System Fault Protection

    Science.gov (United States)

    Day, John; Meakin, Peter; Murray, Alex

    2012-01-01

    Use SysML/UML to describe the physical structure of the system This part of the model would be shared with other teams - FS Systems Engineering, Planning & Execution, V&V, Operations, etc., in an integrated model-based engineering environment Use the UML Profile mechanism, defining Stereotypes to precisely express the concepts of the FP domain This extends the UML/SysML languages to contain our FP concepts Use UML/SysML, along with our profile, to capture FP concepts and relationships in the model Generate typical FP engineering products (the FMECA, Fault Tree, MRD, V&V Matrices)

  17. A Rapid Aeroelastic/Aeroservoelastic Modeling, Analysis and Optimization System for Advanced Flight Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Stirling Dynamics Inc and the University of Washington propose to develop a MATLAB toolbox for rapid aeroelastic (AE) and aeroservoelastic (ASE) modeling, analysis...

  18. The Application of Systems Analysis and Mathematical Models to the Study of Erythropoiesis During Space Flight

    Science.gov (United States)

    Leonard, J. I.

    1974-01-01

    Included in the report are: (1) review of the erythropoietic mechanisms; (2) an evaluation of existing models for the control of erythropoiesis; (3) a computer simulation of the model's response to hypoxia; (4) an hypothesis to explain observed decreases in red blood cell mass during weightlessness; (5) suggestions for further research; and (6) an assessment of the role that systems analysis can play in the Skylab hematological program.

  19. Flight Attendant Work/Rest Patterns, Alertness, and Performance Assessment: Field Validation of Biomathematical Fatigue Modeling

    Science.gov (United States)

    2012-09-01

    Speed (R2=0.539, p<.05), and Lapses (R2=0.901, p<.001). Despite inherent technical limitations and issues of inter -individual variability, these...Aviation Safety Authority [ CASA ], 2010; also see Spencer and Robertson, 2007). mEThOd All human subjects procedures involved in this project were...to the various fatigue-producing inputs accounted for by any given model ( CASA , 2010; Van Dongen, Bender & Dinges 2012). Most model predictions

  20. Establishment and Analysis of Noise Model for Cumulative Flight Events%累积飞行事件噪声模型的建立和分析

    Institute of Scientific and Technical Information of China (English)

    闫国华; 王迪; 魏晓飞; 王彪

    2013-01-01

      多年来,凡是存在机场噪声问题的国家都已先后发展起自己的评价参数,但大多是选取单次飞行事件作为研究对象,而对长期连续的飞行事件还需要考虑飞行事件的次数、飞行时间等因素.由此,基于累积飞行事件的多项数据,建立计权参数模型和最大声级估算模型.其中,对最大声级的估算,根据不同的度量指标采用了多种不同的方法.并采用Delphi7.0软件编程实现航迹的绘制和各参数的计算.研究的结果对于机场的噪声评价有一定的参考价值.%In recent decades, many countries with the problem of airport noise have developed their own evaluation parameters, but most of them selected single flight events as the research objects. However, for the long-term continuous flight events, the number of flight events, flight time and some other factors also need to be considered. In this paper, some of the parametric models based on the data of cumulative flight events were presented, including weighting parameter model and maximum sound level estimation model. Delphi7.0 software was used to draw flight traces and calculate various parameters. Results of this work provide some reference value for airport noise evaluation.

  1. 78 FR 14005 - Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Flight Envelope Protection: Pitch and...

    Science.gov (United States)

    2013-03-04

    ...; Flight Envelope Protection: Pitch and Roll Limiting Functions AGENCY: Federal Aviation Administration... with pitch and roll limiting functions, specifically an electronic flight control system which contains... controls consist of hydraulically powered fly-by-wire elevators, aileron and rudder, controlled by the...

  2. 77 FR 57039 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Electronic Flight Control System...

    Science.gov (United States)

    2012-09-17

    ...; Electronic Flight Control System: Control Surface Awareness and Mode Annunciation AGENCY: Federal Aviation... control system. The applicable airworthiness regulations do not contain adequate or appropriate safety... electronic flight control system and no direct coupling from the flightdeck controller to the control surface...

  3. 78 FR 11553 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Electronic Flight Control System...

    Science.gov (United States)

    2013-02-19

    ... Airplane; Electronic Flight Control System: Control Surface Awareness and Mode Annunciation AGENCY: Federal... control system. The applicable airworthiness regulations do not contain adequate or appropriate safety... a fly-by-wire electronic flight control system and no direct coupling from the flightdeck controller...

  4. 78 FR 68775 - Special Conditions: Airbus, Model A350-900 Series Airplane; Composite Fuselage In-Flight Fire...

    Science.gov (United States)

    2013-11-15

    ...; Composite Fuselage In-Flight Fire/Flammability Resistance AGENCY: Federal Aviation Administration (FAA), DOT... associated with the in-flight fire and flammability resistance of the composite fuselage. Experience has shown that eliminating fire propagation on the surface of interior and insulating materials enhances...

  5. Evaluating galactic cosmic ray environment models using RaD-X flight data

    Science.gov (United States)

    Norman, R. B.; Mertens, C. J.; Slaba, T. C.

    2016-10-01

    Galactic cosmic rays enter Earth's atmosphere after interacting with the geomagnetic field. The primary galactic cosmic rays spectrum is fundamentally changed as it interacts with Earth's atmosphere through nuclear and atomic interactions. At points deeper in the atmosphere, such as at airline altitudes, the radiation environment is a combination of the primary galactic cosmic rays and the secondary particles produced through nuclear interactions. The RaD-X balloon experiment measured the atmospheric radiation environment above 20 km during 2 days in September 2015. These experimental measurements were used to validate and quantify uncertainty in physics-based models used to calculate exposure levels for commercial aviation. In this paper, the Badhwar-O'Neill 2014, the International Organization for Standardization 15390, and the German Aerospace Company galactic cosmic ray environment models are used as input into the same radiation transport code to predict and compare dosimetric quantities to RaD-X measurements. In general, the various model results match the measured tissue equivalent dose well, with results generated by the German Aerospace Center galactic cosmic ray environment model providing the best comparison. For dose equivalent and dose measured in silicon, however, the models were compared less favorably to the measurements.

  6. Flight Test of an Intelligent Flight-Control System

    Science.gov (United States)

    Davidson, Ron; Bosworth, John T.; Jacobson, Steven R.; Thomson, Michael Pl; Jorgensen, Charles C.

    2003-01-01

    The F-15 Advanced Controls Technology for Integrated Vehicles (ACTIVE) airplane (see figure) was the test bed for a flight test of an intelligent flight control system (IFCS). This IFCS utilizes a neural network to determine critical stability and control derivatives for a control law, the real-time gains of which are computed by an algorithm that solves the Riccati equation. These derivatives are also used to identify the parameters of a dynamic model of the airplane. The model is used in a model-following portion of the control law, in order to provide specific vehicle handling characteristics. The flight test of the IFCS marks the initiation of the Intelligent Flight Control System Advanced Concept Program (IFCS ACP), which is a collaboration between NASA and Boeing Phantom Works. The goals of the IFCS ACP are to (1) develop the concept of a flight-control system that uses neural-network technology to identify aircraft characteristics to provide optimal aircraft performance, (2) develop a self-training neural network to update estimates of aircraft properties in flight, and (3) demonstrate the aforementioned concepts on the F-15 ACTIVE airplane in flight. The activities of the initial IFCS ACP were divided into three Phases, each devoted to the attainment of a different objective. The objective of Phase I was to develop a pre-trained neural network to store and recall the wind-tunnel-based stability and control derivatives of the vehicle. The objective of Phase II was to develop a neural network that can learn how to adjust the stability and control derivatives to account for failures or modeling deficiencies. The objective of Phase III was to develop a flight control system that uses the neural network outputs as a basis for controlling the aircraft. The flight test of the IFCS was performed in stages. In the first stage, the Phase I version of the pre-trained neural network was flown in a passive mode. The neural network software was running using flight data

  7. New and Improved Solar Radiation Models for GPS Satellites Based on Flight Data

    Science.gov (United States)

    1997-04-12

    Bar-Sever, Y.E., A New Model for GPS Yaw Attitude, Journal of Geodesy , 70, pp 714-723, 1996. Bar-Sever, Y.E., Strategies for Near Real Time...1983. Watkins, M.M, Bar-Sever, Y.E., Yuan, D-N, Evaluation of GPS orbital Ephemerides with Satellite laser Ranging, Journal of geodesy , 1997

  8. Perception model supports the analysis of vestibular illusions in flight accidents

    NARCIS (Netherlands)

    Groen, E.L.; Houben, M.M.J.; Bos, J.E.; Mumaw, R.J.

    2016-01-01

    TNO and Boeing developed a “Spatial Disorientation Identification Tool” (SDiT) to support the investigation of recorded aircraft motion for its potential to induce Spatial Disorientation (SD). The tool is based on a perception model that consists of transfer functions representing the dynamics in

  9. Flight model performance test results of a helium dewar for the soft X-ray spectrometer onboard ASTRO-H

    Science.gov (United States)

    Yoshida, Seiji; Miyaoka, Mikio; Kanao, Ken'ichi; Tsunematsu, Shoji; Otsuka, Kiyomi; Hoshika, Shunji; Mitsuda, Kazuhisa; Yamasaki, Noriko; Takei, Yoh; Fujimoto, Ryuichi; Sato, Yoichi; DiPirro, Mike; Shirron, Peter

    2016-03-01

    ASTRO-H is a Japanese X-ray astronomy satellite, scheduled to be launched in fiscal year 2015. The mission includes a soft X-ray spectrometer instrument (SXS), which contains an X-ray micro calorimeter operating at 50 mK by using an adiabatic demagnetization refrigerator (ADR). The heat sink of the ADR is superfluid liquid helium below 1.3 K. The required lifetime of the superfluid helium is 3 years or more. In order to realize this lifetime, we have improved the thermal performance from the engineering model (EM) while maintaining the mechanical performance. Then, we have performed a thermal test of the flight model (FM). The results were that the heat load to the helium tank was reduced to below 0.8 mW in the FM from 1.2 mW in the EM. Therefore, the lifetime of the superfluid helium is more than 3 years with 30 L of liquid helium. In this paper, the thermal design and thermal test results are described.

  10. The response of Dahl salt-sensitive and salt-resistant female rats to a space flight model

    Science.gov (United States)

    Thierry-Palmer, Myrtle; Cephas, Stacy; Cleek, Tammy; Sayavongsa, Phouyong; Arnaud, Sara B.

    2003-01-01

    Vitamin D metabolism in the Dahl salt-sensitive (S) rat, a model of salt-induced hypertension, differs from that in the Dahl salt-resistant (R) rat. We have tested the hypothesis that differences in vitamin D metabolism would render the Dahl S rat more susceptible than the Dahl R rat to the effects of a space flight model. Dahl female rats were tail suspended (hind limb unloaded) for 28 days, while fed a low salt (3 g/kg sodium chloride) diet. Plasma 25-OHD concentrations of S rats were significantly lower than that of R rats. Plasma 1,25-(OH)2D concentration was 50% lower in unloaded than in loaded S rats, but was unaffected in unloaded R rats. The left soleus muscle weight and breaking strength of the left femur (torsion test) were 50% and 25% lower in unloaded than in loaded S and R rats. The mineral content of the left femur, however, was significantly lower (by 11%) only in unloaded S rats. We conclude that female S rats are more vulnerable than female R rats to decreases in plasma 1,25-(OH)2D concentration and femur mineral content during hind limb unloading, but equally vulnerable to muscle atrophy and reduced breaking strength of the femur.

  11. Long duration flights management

    Science.gov (United States)

    Sosa-Sesma, Sergio; Letrenne, Gérard; Spel, Martin; Charbonnier, Jean-Marc

    Long duration flights (LDF) require a special management to take the best decisions in terms of ballast consumption and instant of separation. As a contrast to short duration flights, where meteorological conditions are relatively well known, for LDF we need to include the meteorological model accuracy in trajectory simulations. Dispersions on the fields of model (wind, temperature and IR fluxes) could make the mission incompatible with safety rules, authorized zones and others flight requirements. Last CNES developments for LDF act on three main axes: 1. Although ECMWF-NCEP forecast allows generating simulations from a 4D point (altitude, latitude, longitude and UT time), result is not statistical, it is determinist. To take into account model dispersion a meteorological NCEP data base was analyzed. A comparison between Analysis (AN) and Forecast (FC) for the same time frame had been done. Result obtained from this work allows implementing wind and temperature dispersions on balloon flight simulator. 2. For IR fluxes, NCEP does not provide ascending IR fluxes in AN mode but only in FC mode. To obtain the IR fluxes for each time frame, satellite images are used. A comparison between FC and satellites measurements had been done. Results obtained from this work allow implementing flux dispersions on balloon flight simulator. 3. An improved cartography containing a vast data base had been included in balloon flight simulator. Mixing these three points with balloon flight dynamics we have obtained two new tools for observing balloon evolution and risk, one of them is called ASTERISK (Statistic Tool for Evaluation of Risk) for calculations and the other one is called OBERISK (Observing Balloon Evolution and Risk) for visualization. Depending on the balloon type (super pressure, zero pressure or MIR) relevant information for the flight manager is different. The goal is to take the best decision according to the global situation to obtain the largest flight duration with

  12. An experiment to study the effects of space flight cells of mesenchymal origin in the new model 3D-graft in vitro

    Science.gov (United States)

    Volova, Larissa

    One of the major health problems of the astronauts are disorders of the musculoskeletal system, which determines the relevance of studies of the effect of space flight factors on osteoblastic and hondroblastic cells in vitro. An experiment to study the viability and proliferative activity of cells of mesenchymal origin on culture: chondroblasts and dermal fibroblasts was performed on SC "BION -M" № 1 with scientific equipment " BIOKONT -B ." To study the effect of space flight conditions in vitro at the cellular level has developed a new model with 3D- graft as allogeneic demineralized spongiosa obtained on technology Lioplast ®. For space and simultaneous experiments in the laboratory of the Institute of Experimental Medicine and Biotechnology Samara State Medical University were obtained from the cell culture of hyaline cartilage and human skin, which have previously been grown, and then identified by morphological and immunohistochemical methods. In the experiment, they were seeded on the porous 3D- graft (controlled by means of scanning electron and confocal microscopy) and cultured in full growth medium. After completion of the flight of spacecraft "BION -M" № 1 conducted studies of biological objects using a scanning electron microscope (JEOL JSM-6390A Analysis Station, Japan), confocal microscopy and LDH - test. According to the results of the experiment revealed that after a 30- day flight of the cells not only retained vitality, but also during the flight actively proliferate, and their number has increased by almost 8 times. In synchronous experiment, all the cells died by this date. The experimentally confirmed the adequacy of the proposed model 3D- graft in studying the effect of space flight on the morphological and functional characteristics of cells in vitro.

  13. Atmospheric Modeling Using Accelerometer Data During Mars Atmosphere and Volatile Evolution (MAVEN) Flight Operations

    Science.gov (United States)

    Tolson, Robert H.; Lugo, Rafael A.; Baird, Darren T.; Cianciolo, Alicia D.; Bougher, Stephen W.; Zurek, Richard M.

    2017-01-01

    The Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft is a NASA orbiter designed to explore the Mars upper atmosphere, typically from 140 to 160 km altitude. In addition to the nominal science mission, MAVEN has performed several Deep Dip campaigns in which the orbit's closest point of approach, also called periapsis, was lowered to an altitude range of 115 to 135 km. MAVEN accelerometer data were used during mission operations to estimate atmospheric parameters such as density, scale height, along-track gradients, and wave structures. Density and scale height estimates were compared against those obtained from the Mars Global Reference Atmospheric Model and used to aid the MAVEN navigation team in planning maneuvers to raise and lower periapsis during Deep Dip operations. This paper describes the processes used to reconstruct atmosphere parameters from accelerometers data and presents the results of their comparison to model and navigation-derived values.

  14. In-Flight System Identification

    Science.gov (United States)

    Morelli, Eugene A.

    1998-01-01

    A method is proposed and studied whereby the system identification cycle consisting of experiment design and data analysis can be repeatedly implemented aboard a test aircraft in real time. This adaptive in-flight system identification scheme has many advantages, including increased flight test efficiency, adaptability to dynamic characteristics that are imperfectly known a priori, in-flight improvement of data quality through iterative input design, and immediate feedback of the quality of flight test results. The technique uses equation error in the frequency domain with a recursive Fourier transform for the real time data analysis, and simple design methods employing square wave input forms to design the test inputs in flight. Simulation examples are used to demonstrate that the technique produces increasingly accurate model parameter estimates resulting from sequentially designed and implemented flight test maneuvers. The method has reasonable computational requirements, and could be implemented aboard an aircraft in real time.

  15. Modeling of a sensitive time-of-flight flash LiDAR system

    Science.gov (United States)

    Fathipour, V.; Wheaton, S.; Johnson, W. E.; Mohseni, H.

    2016-09-01

    used for monitoring and profiling structures, range, velocity, vibration, and air turbulence. Remote sensing in the IR region has several advantages over the visible region, including higher transmitter energy while maintaining eye-safety requirements. Electron-injection detectors are a new class of detectors with high internal avalanche-free amplification together with an excess-noise-factor of unity. They have a cutoff wavelength of 1700 nm. Furthermore, they have an extremely low jitter. The detector operates in linear-mode and requires only bias voltage of a few volts. This together with the feedback stabilized gain mechanism, makes formation of large-format high pixel density electron-injection FPAs less challenging compared to other detector technologies such as avalanche photodetectors. These characteristics make electron-injection detectors an ideal choice for flash LiDAR application with mm scale resolution at longer ranges. Based on our experimentally measured device characteristics, a detailed theoretical LiDAR model was developed. In this model we compare the performance of the electron-injection detector with commercially available linear-mode InGaAs APD from (Hamamatsu G8931-20) as well as a p-i-n diode (Hamamatsu 11193 p-i-n). Flash LiDAR images obtained by our model, show the electron-injection detector array (of 100 x 100 element) achieves better resolution with higher signal-to-noise compared with both the InGaAs APD and the p-i-n array (of 100 x 100 element).

  16. Vortex Wake Geometry of a Model Tilt Rotor in Forward Flight

    Science.gov (United States)

    Yamauchi, G. K.; Johnson, W.; Wadcock, A. J.

    2002-01-01

    The vortex wake trajectory from one rotor of a 0.25-scale V-22 tiltrotor model was measured for four test conditions in the NASA Ames 40- by 80-Foot Wind Tunnel. Vortex wake images were acquired using a laser light sheet and video camera. Wake trajectories were constructed by extracting vortex positions from the video images. Wake trajectories were also calculated using the comprehensive analysis CAMRAD II. Measured and calculated wake geometries exhibit similar trends when advance ratio is varied at fixed thrust or when thrust is varied at fixed advance ratio.

  17. Mathematical modeling of acute and chronic cardiovascular changes during Extended Duration Orbiter (EDO) flights

    Science.gov (United States)

    White, Ronald J.; Leonard, Joel I.; Srinivasan, R. Srini; Charles, John B.

    1991-01-01

    The purpose of NASA's Extended Duration Orbiter program is a gradual extension of the capabilities of the Space Shuttle Orbiter beyond its current 7-10 day limit on mission duration, as warranted by deepening understanding of the long-term physiological effects of weightlessness. Attention is being given to the cardiovascular problem of orthostatic tolerance loss due to its adverse effects on crew performance and health during reentry and initial readaptation to earth gravity. An account is given of the results of the application of proven mathematical models of circulatory and cardiovascular systems under microgravity conditions.

  18. Two-Dimensional Aerodynamic Models of Insect Flight for Robotic Flapping Wing Mechanisms of Maximum Efficiency

    Institute of Scientific and Technical Information of China (English)

    Thien-Tong Nguyen; Doyoung Byun

    2008-01-01

    In the "modified quasi-steady" approach, two-dimensional (2D) aerodynamic models of flapping wing motions are analyzed with focus on different types of wing rotation and different positions of rotation axis to explain the force peak at the end of each half stroke. In this model, an additional velocity of the mid chord position due to rotation is superimposed on the translational relative velocity of air with respect to the wing. This modification produces augmented forces around the end of eachstroke. For each case of the flapping wing motions with various combination of controlled translational and rotational velocities of the wing along inclined stroke planes with thin figure-of-eight trajectory, discussions focus on lift-drag evolution during one stroke cycle and efficiency of types of wing rotation. This "modified quasi-steady" approach provides a systematic analysis of various parameters and their effects on efficiency of flapping wing mechanism. Flapping mechanism with delayed rotation around quarter-chord axis is an efficient one and can be made simple by a passive rotation mechanism so that it can be useful for robotic application.

  19. EXPERIMENTAL INVESTIGATION OF THE IMPACT OF FLIGHT SPEED ON DRAG FORCE IN THE AUTOGYRO MODEL

    Directory of Open Access Journals (Sweden)

    Zbigniew Czyż

    2015-05-01

    Full Text Available The paper presents the experimental investigation of the impact of velocity on drag force in the autogyro model. One of the methods which simulate motion of the flying object consists of using a wind tunnel. In this case, test object is stationary and the motion of air is forced by e.g. a special fan. The costs related with renting and the wind tunnel service are still very high. In this paper, the motion of the autogyro with respect to the air, was produced by fixing this model with scale to measure the drag force on the passenger car roof. The position of the object relative to the vehicle was checked on the basis of numerical analysis of the airflow around this vehicle. Based on the investigations, the field of velocity and pressure, and air flow formed around the contour of the vehicle which have been chosen, were determined. In addition, the drag force characteristic was determined as a function of velocity and it was compared with the values from the numerical analysis. This research is a form of verifying opportunities for this type of research on vehicles. The conclusions derived from the analysis of the results will be used in the future to carry out further research.

  20. Lévy Flights and Self-Similar Exploratory Behaviour of Termite Workers: Beyond Model Fitting

    Science.gov (United States)

    Miramontes, Octavio; DeSouza, Og; Paiva, Leticia Ribeiro; Marins, Alessandra; Orozco, Sirio

    2014-01-01

    Animal movements have been related to optimal foraging strategies where self-similar trajectories are central. Most of the experimental studies done so far have focused mainly on fitting statistical models to data in order to test for movement patterns described by power-laws. Here we show by analyzing over half a million movement displacements that isolated termite workers actually exhibit a range of very interesting dynamical properties –including Lévy flights– in their exploratory behaviour. Going beyond the current trend of statistical model fitting alone, our study analyses anomalous diffusion and structure functions to estimate values of the scaling exponents describing displacement statistics. We evince the fractal nature of the movement patterns and show how the scaling exponents describing termite space exploration intriguingly comply with mathematical relations found in the physics of transport phenomena. By doing this, we rescue a rich variety of physical and biological phenomenology that can be potentially important and meaningful for the study of complex animal behavior and, in particular, for the study of how patterns of exploratory behaviour of individual social insects may impact not only their feeding demands but also nestmate encounter patterns and, hence, their dynamics at the social scale. PMID:25353958

  1. FLIGHT INFORMATION

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Check in With Singapore Airlines, Check out With Paypal Singapore Airlines customers in the United States, Singapore and five other Asia Pacific countries and territories can now pay for their flights with PayPal on singaporeair.com. This facility will progressively be made available to the airline’s customers in up to 17 countries, making this the largest collaboration between PayPal and an Asian carrier to date.

  2. Technique for Assessing the Stability and Controllability Characteristics of Naval Aircraft Systems Based on the Rational Combination of Modeling, Identification and Flight Experiments

    Directory of Open Access Journals (Sweden)

    S. V. Nikolaev

    2015-01-01

    Full Text Available The aim of this work is to improve test quality and reliability of modern naval aircraft for assessment of stability and controllability characteristics and test shortening. To achieve this goal it is necessary to develop an algorithmic, mathematical and methodological support of the flight trials and the mathematical modeling of controlled flight modes to determine the stability and controllability characteristics of the naval aircraft.The article analyses the problems related to determining the stability and controllability characteristics under flight tests, describes the technique to correct a mathematical model of aerodynamic characteristics and engine thrust forces of modern naval aircraft. It shows the importance of using algorithm to control the correctness of onboard measurements of flight parameters. The article presents new results of identification of the aircraft aerodynamic coefficients and proves that in identifying characteristics of the longitudinal control channel it is necessary to take into account the engine thrust forces. In the article the aerodynamic coefficients, obtained by identification methods, are compared with those in the original aerodynamic data Bank.An important and new component of the work described in the fourth part of the article, is a set of computer programmes, integrated into a common interface. The development of this software has greatly improved a processing technology of the flight experiment materials and identification of the aerodynamic characteristics of the aircraft.When applying the work results in the testing phase, the required characteristics of stability and controllability are determined by simulation, and identification provides the model refinement according to the flight data.The created technology of practical identification is used to verify and refine the mathematical models according to the flight experiment data. Thus, the result is a proven and refined model of the aircraft

  3. 2001 Flight Mechanics Symposium

    Science.gov (United States)

    Lynch, John P. (Editor)

    2001-01-01

    This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium held on June 19-21, 2001. Sponsored by the Guidance, Navigation and Control Center of Goddard Space Flight Center, this symposium featured technical papers on a wide range of issues related to attitude/orbit determination, prediction and control; attitude simulation; attitude sensor calibration; theoretical foundation of attitude computation; dynamics model improvements; autonomous navigation; constellation design and formation flying; estimation theory and computational techniques; Earth environment mission analysis and design; and, spacecraft re-entry mission design and operations.

  4. Radiative Heating in MSL Entry: Comparison of Flight Heating Discrepancy to Ground Test and Predictive Models

    Science.gov (United States)

    Cruden, Brett A.; Brandis, Aaron M.; White, Todd R.; Mahzari, Milad; Bose, Deepak

    2014-01-01

    During the recent entry of the Mars Science Laboratory (MSL), the heat shield was equipped with thermocouple stacks to measure in-depth heating of the thermal protection system (TPS). When only convective heating was considered, the derived heat flux from gauges in the stagnation region was found to be underpredicted by as much as 17 W/sq cm, which is significant compared to the peak heating of 32 W/sq cm. In order to quantify the contribution of radiative heating phenomena to the discrepancy, ground tests and predictive simulations that replicated the MSL entry trajectory were performed. An analysis is carried through to assess the quality of the radiation model and the impact to stagnation line heating. The impact is shown to be significant, but does not fully explain the heating discrepancy.

  5. Madam - a map-making method for CMB experiments

    CERN Document Server

    Keihanen, E; Poutanen, T

    2004-01-01

    We present a new map-making method for CMB measurements. The method is based on the destriping technique, but it also utilizes information about the noise spectrum. The low-frequency component of the instrument noise stream is modelled as a superposition of a set of simple base functions, whose amplitudes are determined by means of maximum-likelihood analysis, involving the covariance matrix of the amplitudes. We present simulation results with $1/f$ noise and show a reduction in the residual noise with respect to ordinary destriping. This study is related to \\Planck LFI activities.

  6. SCRL-Model for Human Space Flight Operations Enterprise Supply Chain

    Science.gov (United States)

    Tucker, Brian; Paxton, Joseph

    2010-01-01

    This paper will present a Supply Chain Readiness Level (SCRL) model that can be used to evaluate and configure adaptable and sustainable program and mission supply chains at an enterprise level. It will also show that using SCRL in conjunction with Technology Readiness Levels (TRLs), Manufacturing Readiness Levels (MRLs) and National Aeronautics Space Administrations (NASA s) Project Lifecycle Process will provide a more complete means of developing and evaluating a robust sustainable supply chain that encompasses the entire product, system and mission lifecycle. In addition, it will be shown that by implementing the SCRL model, NASA can additionally define supplier requirements to enable effective supply chain management (SCM). Developing and evaluating overall supply chain readiness for any product, system and mission lifecycle is critical for mission success. Readiness levels are presently being used to evaluate the maturity of technology and manufacturing capability during development and deployment phases of products and systems. For example, TRLs are used to support the assessment of the maturity of a particular technology and compare maturity of different types of technologies. MRLs are designed to assess the maturity and risk of a given technology from a manufacturing perspective. In addition, when these measurement systems are used collectively they can offer a more comprehensive view of the maturity of the system. While some aspects of the supply chain and supply chain planning are considered in these familiar metric systems, certain characteristics of an effective supply chain, when evaluated in more detail, will provide an improved insight into the readiness and risk throughout the supply chain. Therefore, a system that concentrates particularly on supply chain attributes is required to better assess enterprise supply chain readiness.

  7. SCRL-Model for Human Space Flight Operations Enterprise Supply Chain

    Science.gov (United States)

    Tucker, Brian; Paxton, Joseph

    2010-01-01

    This paper will present a Supply Chain Readiness Level (SCRL) model that can be used to evaluate and configure adaptable and sustainable program and mission supply chains at an enterprise level. It will also show that using SCRL in conjunction with Technology Readiness Levels (TRLs), Manufacturing Readiness Levels (MRLs) and National Aeronautics Space Administrations (NASA s) Project Lifecycle Process will provide a more complete means of developing and evaluating a robust sustainable supply chain that encompasses the entire product, system and mission lifecycle. In addition, it will be shown that by implementing the SCRL model, NASA can additionally define supplier requirements to enable effective supply chain management (SCM). Developing and evaluating overall supply chain readiness for any product, system and mission lifecycle is critical for mission success. Readiness levels are presently being used to evaluate the maturity of technology and manufacturing capability during development and deployment phases of products and systems. For example, TRLs are used to support the assessment of the maturity of a particular technology and compare maturity of different types of technologies. MRLs are designed to assess the maturity and risk of a given technology from a manufacturing perspective. In addition, when these measurement systems are used collectively they can offer a more comprehensive view of the maturity of the system. While some aspects of the supply chain and supply chain planning are considered in these familiar metric systems, certain characteristics of an effective supply chain, when evaluated in more detail, will provide an improved insight into the readiness and risk throughout the supply chain. Therefore, a system that concentrates particularly on supply chain attributes is required to better assess enterprise supply chain readiness.

  8. An automated nowcasting model of significant instability events in the flight terminal area of Rio de Janeiro, Brazil

    Science.gov (United States)

    Borges França, Gutemberg; Valdonel de Almeida, Manoel; Rosette, Alessana C.

    2016-05-01

    This paper presents a novel model, based on neural network techniques, to produce short-term and local-specific forecasts of significant instability for flights in the terminal area of Galeão Airport, Rio de Janeiro, Brazil. Twelve years of data were used for neural network training/validation and test. Data are originally from four sources: (1) hourly meteorological observations from surface meteorological stations at five airports distributed around the study area; (2) atmospheric profiles collected twice a day at the meteorological station at Galeão Airport; (3) rain rate data collected from a network of 29 rain gauges in the study area; and (4) lightning data regularly collected by national detection networks. An investigation was undertaken regarding the capability of a neural network to produce early warning signs - or as a nowcasting tool - for significant instability events in the study area. The automated nowcasting model was tested using results from five categorical statistics, indicated in parentheses in forecasts of the first, second, and third hours, respectively, namely proportion correct (0.99, 0.97, and 0.94), BIAS (1.10, 1.42, and 2.31), the probability of detection (0.79, 0.78, and 0.67), false-alarm ratio (0.28, 0.45, and 0.73), and threat score (0.61, 0.47, and 0.25). Possible sources of error related to the test procedure are presented and discussed. The test showed that the proposed model (or neural network) can grab the physical content inside the data set, and its performance is quite encouraging for the first and second hours to nowcast significant instability events in the study area.

  9. 78 FR 31838 - Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Flight Envelope Protection: General...

    Science.gov (United States)

    2013-05-28

    ... for normal takeoff. The primary flight controls consist of hydraulically powered fly-by-wire elevators... envelope protection features include limitations on angle-of- attack, normal load factor, bank angle, pitch...

  10. 78 FR 5148 - Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Flight Envelope Protection: General...

    Science.gov (United States)

    2013-01-24

    ... for normal takeoff. The primary flight controls consist of hydraulically powered fly-by-wire elevators... envelope protection features include limitations on angle-of- attack, normal load factor, bank angle, pitch...

  11. Development and Implementation of a Model-Driven Envelope Protection System for In-Flight Ice Contamination

    Science.gov (United States)

    Gingras, David R.; Barnhart, Billy P.; Martos, Borja; Ratvasky, Thomas P.; Morelli, Eugene

    2011-01-01

    Fatal loss-of-control (LOC) accidents have been directly related to in-flight airframe icing. The prototype system presented in this paper directly addresses the need for real-time onboard envelope protection in icing conditions. The combinations of a-priori information and realtime aerodynamic estimations are shown to provide sufficient input for determining safe limits of the flight envelope during in-flight icing encounters. The Icing Contamination Envelope Protection (ICEPro) system has been designed and implemented to identify degradations in airplane performance and flying qualities resulting from ice contamination and provide safe flight-envelope cues to the pilot. Components of ICEPro are described and results from preliminary tests are presented.

  12. Eclipse takeoff and flight

    Science.gov (United States)

    1998-01-01

    made by the simulation, aerodynamic characteristics and elastic properties of the tow rope were a significant component of the towing system; and the Dryden high-fidelity simulation provided a representative model of the performance of the QF-106 and C-141A airplanes in tow configuration. Total time on tow for the entire project was 5 hours, 34 minutes, and 29 seconds. All six flights were highly productive, and all project objectives were achieved. All three of the project objectives were successfully accomplished. The objectives were: demonstration of towed takeoff, climb-out, and separation of the EXD-01 from the towing aircraft; validation of simulation models of the towed aircraft systems; and development of ground and flight procedures for towing and launching a delta-winged airplane configuration safely behind a transport-type aircraft. NASA Dryden served as the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden also supplied engineering, simulation, instrumentation, range support, research pilots, and chase aircraft for the test series. Dryden personnel also performed the modifications to convert the QF-106 into the piloted EXD-01 aircraft. During the early flight phase of the project, Tracor, Inc. provided maintenance and ground support for the two QF-106 airplanes. The Air Force Flight Test Center (AFFTC), Edwards, California, provided the C-141A transport aircraft for the project, its flight and engineering support, and the aircrew. Kelly Space and Technology provided the modification design and fabrication of the hardware that was installed on the EXD-01 aircraft. Kelly Space and Technology hopes to use the data gleaned from the tow tests to develop a series of low-cost reusable launch vehicles, in particular to gain experience towing delta-wing aircraft having high wing loading, and in general to demonstrate various operational procedures such as ground processing and abort scenarios. The first successful

  13. Efficient chain moves for Monte Carlo simulations of a wormlike DNA model: excluded volume, supercoils, site juxtapositions, knots, and comparisons with random-flight and lattice models.

    Science.gov (United States)

    Liu, Zhirong; Chan, Hue Sun

    2008-04-14

    We develop two classes of Monte Carlo moves for efficient sampling of wormlike DNA chains that can have significant degrees of supercoiling, a conformational feature that is key to many aspects of biological function including replication, transcription, and recombination. One class of moves entails reversing the coordinates of a segment of the chain along one, two, or three axes of an appropriately chosen local frame of reference. These transformations may be viewed as a generalization, to the continuum, of the Madras-Orlitsky-Shepp algorithm for cubic lattices. Another class of moves, termed T+/-2, allows for interconversions between chains with different lengths by adding or subtracting two beads (monomer units) to or from the chain. Length-changing moves are generally useful for conformational sampling with a given site juxtaposition, as has been shown in previous lattice studies. Here, the continuum T+/-2 moves are designed to enhance their acceptance rate in supercoiled conformations. We apply these moves to a wormlike model in which excluded volume is accounted for by a bond-bond repulsion term. The computed autocorrelation functions for the relaxation of bond length, bond angle, writhe, and branch number indicate that the new moves lead to significantly more efficient sampling than conventional bead displacements and crankshaft rotations. A close correspondence is found in the equilibrium ensemble between the map of writhe computed for pair of chain segments and the map of site juxtapositions or self-contacts. To evaluate the more coarse-grained freely jointed chain (random-flight) and cubic lattice models that are commonly used in DNA investigations, twisting (torsional) potentials are introduced into these models. Conformational properties for a given superhelical density sigma may then be sampled by computing the writhe and using White's formula to relate the degree of twisting to writhe and sigma. Extensive comparisons of contact patterns and knot

  14. Experiment K-310: The effect of space flight on ostenogenesis and dentinogenesis in the mandible of rats. Supplement 1: The effects of space flight on alveolar bone modeling and remodeling in the rat mandible

    Science.gov (United States)

    Van, P. T.; Vignery, A.; Bacon, R.

    1981-01-01

    The histomorphometric study of alveolar bone, a non-weight-bearing bone submitted mainly to the mechanical stimulations of mastication, showed that space flight decreases the remodeling activity but does not induce a negative balance between resorption and formation. The most dramatic effect of space flight has been observed along the periosteal surface, and especially in areas not covered with masticatory muscles, where bone formation almost stopped completely during the flight period. This bone, having been submitted to the same mechanical forces in the flight animals and the controls, leads to the conclusion that factors other than mechanical loading might be involved in the decreased bone formation during flight.

  15. Vision based flight procedure stereo display system

    Science.gov (United States)

    Shen, Xiaoyun; Wan, Di; Ma, Lan; He, Yuncheng

    2008-03-01

    A virtual reality flight procedure vision system is introduced in this paper. The digital flight map database is established based on the Geographic Information System (GIS) and high definitions satellite remote sensing photos. The flight approaching area database is established through computer 3D modeling system and GIS. The area texture is generated from the remote sensing photos and aerial photographs in various level of detail. According to the flight approaching procedure, the flight navigation information is linked to the database. The flight approaching area vision can be dynamic displayed according to the designed flight procedure. The flight approaching area images are rendered in 2 channels, one for left eye images and the others for right eye images. Through the polarized stereoscopic projection system, the pilots and aircrew can get the vivid 3D vision of the flight destination approaching area. Take the use of this system in pilots preflight preparation procedure, the aircrew can get more vivid information along the flight destination approaching area. This system can improve the aviator's self-confidence before he carries out the flight mission, accordingly, the flight safety is improved. This system is also useful in validate the visual flight procedure design, and it helps to the flight procedure design.

  16. Dynamic Flight Simulation of aircraft and its comparison to Flight tests

    Directory of Open Access Journals (Sweden)

    Reza Khaki

    2015-09-01

    Full Text Available Nowadays obtaining data for air vehicles researches and analyses is very expensive and risky through the flight tests. Therefore using flight simulation is usually used for the mentioned researches by aerospace science researchers. In this paper, dynamic flight simulation has been performed by airplane nonlinear equations modelling. In these equations, aerodynamic coefficients and stability derivatives have an important role. Therefore, the stability derivatives for typical aircraft are calculated on various flight conditions by analytical and numerical methods. Flight conditions include of Mach number, altitude, angle of attack, control surfaces and CG position variations. The obtained derivatives are used in the form of look up table for dynamic flight simulation and virtual flight. In order to validate the simulation results, the under investigation maneuvres parameters are recorded during many real flights. The obtained data from flight tests are compared with the outputs of flight simulations. The results indicate that less than 13% differences are found in different parts of the maneuvres.

  17. Energetic influence on gull flight strategy selection

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; van Loon, E.E.

    2006-01-01

    During non-migratory flight, gulls (Larids) use a wide variety of flight strategies. We investigate the extent to which the energy balance of a bird explains flight strategy selection. We develop a model based on optimal foraging and aerodynamic theories, to calculate the ground speeds and airspeeds

  18. Flight Model Discharge System

    Science.gov (United States)

    1988-06-01

    Dielectric Sensor ................................... 12 5 ESA S/N 001 ......................................... 24 6 Preliminary Test Sequence...71 28 Optical Transmission Loss of Contamination "Witness" Slide 3 .................................. 72 29 Apparatus used in FMDS Spectroscopic...Monitor ( TPU ). This sensor detects the electromagnetic pulses generated by the onset of arcing. (2) An active discharge device (plasma source). (3) A

  19. Iced Aircraft Flight Data for Flight Simulator Validation

    Science.gov (United States)

    Ratvasky, Thomas P.; Blankenship, Kurt; Rieke, William; Brinker, David J.

    2003-01-01

    NASA is developing and validating technology to incorporate aircraft icing effects into a flight training device concept demonstrator. Flight simulation models of a DHC-6 Twin Otter were developed from wind tunnel data using a subscale, complete aircraft model with and without simulated ice, and from previously acquired flight data. The validation of the simulation models required additional aircraft response time histories of the airplane configured with simulated ice similar to the subscale model testing. Therefore, a flight test was conducted using the NASA Twin Otter Icing Research Aircraft. Over 500 maneuvers of various types were conducted in this flight test. The validation data consisted of aircraft state parameters, pilot inputs, propulsion, weight, center of gravity, and moments of inertia with the airplane configured with different amounts of simulated ice. Emphasis was made to acquire data at wing stall and tailplane stall since these events are of primary interest to model accurately in the flight training device. Analyses of several datasets are described regarding wing and tailplane stall. Key findings from these analyses are that the simulated wing ice shapes significantly reduced the C , max, while the simulated tail ice caused elevator control force anomalies and tailplane stall when flaps were deflected 30 deg or greater. This effectively reduced the safe operating margins between iced wing and iced tail stall as flap deflection and thrust were increased. This flight test demonstrated that the critical aspects to be modeled in the icing effects flight training device include: iced wing and tail stall speeds, flap and thrust effects, control forces, and control effectiveness.

  20. Laser Altimeter for Flight Simulator

    Science.gov (United States)

    Webster, L. D.

    1986-01-01

    Height of flight-simulator probe above model of terrain measured by automatic laser triangulation system. Airplane simulated by probe that moves over model of terrain. Altitude of airplane scaled from height of probe above model. Height measured by triangulation of laser beam aimed at intersection of model surface with plumb line of probe.

  1. 77 FR 69573 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Electronic Flight Control System...

    Science.gov (United States)

    2012-11-20

    ... takeoff. The primary flight controls consist of hydraulically powered fly-by-wire elevators, aileron and...) Longitudinal Static Stability: Static longitudinal stability on airplanes with mechanical links to the pitch... result in significant changes in attitude, airspeed or load factor. A predictable pitch response is...

  2. 78 FR 11560 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Electronic Flight Control System...

    Science.gov (United States)

    2013-02-19

    ... flight controls consist of hydraulically powered fly-by-wire elevators, aileron and rudder, controlled by...) Longitudinal Static Stability: Static longitudinal stability on airplanes with mechanical links to the pitch... result in significant changes in attitude, airspeed or load factor. A predictable pitch response is...

  3. 77 FR 69572 - Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Flight Envelope Protection: High Speed...

    Science.gov (United States)

    2012-11-20

    ... be found in the Federal Register published on April 11, 2000 (65 FR 19477-19478), as well as at http...; Flight Envelope Protection: High Speed Limiting AGENCY: Federal Aviation Administration (FAA), DOT... inadvertently or intentionally exceeding a speed approximately equivalent to V FC or attaining V DF ....

  4. Spontaneous Flapping Flight

    Science.gov (United States)

    Vandenberghe, Nicolas; Zhang, Jun; Childress, Stephen

    2004-11-01

    As shown in an earlier work [Vandenberghe, et. al. JFM, Vol 506, 147, 2004], a vertically flapping wing can spontaneously move horizontally as a result of symmetry breaking. In the current experimental study, we investigate the dependence of resultant velocity on flapping amplitude. We also describe the forward thrust generation and how the system dynamically selects a Strouhal number by balancing fluid and body forces. We further compare our model system with examples of biological locomotion, such as bird flight and fish swimming.

  5. Bumblebee flight in heavy turbulence

    CERN Document Server

    Engels, T; Schneider, K; Lehmann, F -O; Sesterhenn, J

    2016-01-01

    High-resolution numerical simulations of a tethered model bumblebee in forward flight are performed superimposing homogeneous isotropic turbulent fluctuations to the uniform inflow. Despite tremendous variation in turbulence intensity, between 17% and 99% with respect to the mean flow, we do not find significant changes in cycle-averaged aerodynamic forces, moments or flight power when averaged over realizations, compared to laminar inflow conditions. The variance of aerodynamic measures, however, significantly increases with increasing turbulence intensity, which may explain flight instabilities observed in freely flying bees.

  6. Supersonic Flight Dynamics Test 1 - Post-Flight Assessment of Simulation Performance

    Science.gov (United States)

    Dutta, Soumyo; Bowes, Angela L.; Striepe, Scott A.; Davis, Jody L.; Queen, Eric M.; Blood, Eric M.; Ivanov, Mark C.

    2015-01-01

    NASA's Low Density Supersonic Decelerator (LDSD) project conducted its first Supersonic Flight Dynamics Test (SFDT-1) on June 28, 2014. Program to Optimize Simulated Trajectories II (POST2) was one of the flight dynamics codes used to simulate and predict the flight performance and Monte Carlo analysis was used to characterize the potential flight conditions experienced by the test vehicle. This paper compares the simulation predictions with the reconstructed trajectory of SFDT-1. Additionally, off-nominal conditions seen during flight are modeled in post-flight simulations to find the primary contributors that reconcile the simulation with flight data. The results of these analyses are beneficial for the pre-flight simulation and targeting of the follow-on SFDT flights currently scheduled for summer 2015.

  7. 基于SysML的飞控系统模型重用技术%Model reuse technology of the flight control system based on SysML

    Institute of Scientific and Technical Information of China (English)

    张昕; 曹云峰; 庄丽奎; 王彪; 王西超; 王平

    2013-01-01

    A new model reuse method of flight control system virtual prototype is proposed Based on the Systems Modeling Language(SysML) Components(BSC), namely US-BP(Unit, Structure; Behavior, Process) method, which can improve the methods of virtual prototype-oriented system analysis and description. Taking a certain type of four-rotor UAV as example, the implementation of the flight control system virtual prototype supporting model reuse is described-the simulation, design and implementation are based on SysML components and Simulink components simultaneously. It provides an important technology for the model reuse in the modeling and simulation of the flight control system.%针对飞控系统建模中的模型重用问题,改进面向虚拟样机的系统分析和描述方法,提出一种基于系统工程建模语言(SysML)组件(BSC)的飞行控制系统虚拟样机模型重用方法,即“部件、结构;行为、过程”(US-BP)方法;以某型四旋翼无人机为例,说明了飞控系统虚拟样机支持模型重用的实现方式,即基于 SysML 组件与 Simulink 组件的仿真设计与实现方法。本文为飞控系统建模与仿真领域中的模型重用提供了重要的技术途径。

  8. Context-dependent flight speed: evidence for energetically optimal flight speed in the bat Pipistrellus kuhlii?

    Science.gov (United States)

    Grodzinski, Uri; Spiegel, Orr; Korine, Carmi; Holderied, Marc W

    2009-05-01

    1. Understanding the causes and consequences of animal flight speed has long been a challenge in biology. Aerodynamic theory is used to predict the most economical flight speeds, minimizing energy expenditure either per distance (maximal range speed, Vmr) or per time (minimal power speed, Vmp). When foraging in flight, flight speed also affects prey encounter and energy intake rates. According to optimal flight speed theory, such effects may shift the energetically optimal foraging speed to above Vmp. 2. Therefore, we predicted that if energetic considerations indeed have a substantial effect on flight speed of aerial-hawking bats, they will use high speed (close to Vmr) to commute from their daily roost to the foraging sites, while a slower speed (but still above Vmp) will be preferred during foraging. To test these predictions, echolocation calls of commuting and foraging Pipistrellus kuhlii were recorded and their flight tracks were reconstructed using an acoustic flight path tracking system. 3. Confirming our qualitative prediction, commuting flight was found to be significantly faster than foraging flight (9.3 vs. 6.7 m s(-1)), even when controlling for its lower tortuosity. 4. In order to examine our quantitative prediction, we compared observed flight speeds with Vmp and Vmr values generated for the study population using two alternative aerodynamic models, based on mass and wing morphology variables measured from bats we captured while commuting. The Vmp and Vmr values generated by one of the models were much lower than our measured flight speed. According to the other model used, however, measured foraging flight was faster than Vmp and commuting flight slightly slower than Vmr, which is in agreement with the predictions of optimal flight speed theory. 5. Thus, the second aerodynamic model we used seems to be a reasonable predictor of the different flight speeds used by the bats while foraging and while commuting. This supports the hypothesis that bats fly

  9. Make Flights Fly More Safe--An interview with Fan Zhizhong, a national civil aviation labour model

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正>Pudong International Airport handles more than 500 flights daily. As a plane lands, its tyres will leave rubber on the runaway as they rub against it, which will reduce the coefficient of friction between tyres and the runway. When the coefficient is below the lowest standard of 0.41, the landing safety will be greatly affected. Therefore, the rubber on the runway must be cleared away at regular

  10. Rocket Flight Path

    Directory of Open Access Journals (Sweden)

    Jamie Waters

    2014-09-01

    Full Text Available This project uses Newton’s Second Law of Motion, Euler’s method, basic physics, and basic calculus to model the flight path of a rocket. From this, one can find the height and velocity at any point from launch to the maximum altitude, or apogee. This can then be compared to the actual values to see if the method of estimation is a plausible. The rocket used for this project is modeled after Bullistic-1 which was launched by the Society of Aeronautics and Rocketry at the University of South Florida.

  11. Extensive air shower Monte Carlo modeling at the ground and aircraft flight altitude in the South Atlantic Magnetic Anomaly and comparison with neutron measurements

    Science.gov (United States)

    Pazianotto, M. T.; Cortés-Giraldo, M. A.; Federico, C. A.; Hubert, G.; Gonçalez, O. L.; Quesada, J. M.; Carlson, B. V.

    2017-02-01

    Modeling cosmic-ray-induced particle fluxes in the atmosphere is very important for developing many applications in aeronautics, space weather and on ground experimental arrangements. There is a lack of measurements and modeling at flight altitude and on ground in the South Atlantic Magnetic Anomaly. In this work we have developed an application based on the Geant4 toolkit called gPartAt that is aimed at the analysis of extensive air shower particle spectra. Another application has been developed using the MCNPX code with the same approach in order to evaluate the models and nuclear data libraries used in each application. Moreover, measurements were performed to determine the ambient dose equivalent rate of neutrons at flight altitude in different regions and dates in the Brazilian airspace; these results were also compared with the simulations. The results from simulations of the neutron spectra at ground level were also compared to data from a neutron spectrometer in operation since February 2015 at the Pico dos Dias Observatory in Brazil, at 1864 m above sea level, as part of a collaboration between the Institute for Advanced Studies (IEAv) and the French Aerospace Lab (ONERA). This measuring station is being operated with support from the National Astrophysics Laboratory (LNA). The modeling approaches were also compared to the AtmoRad computational platform, QARM, EXPACS codes and with measurements of the neutron spectrum taken in 2009 at the Pico dos Dias Observatory.

  12. Dynamic stall in flapping flight

    Science.gov (United States)

    Hubel, Tatjana; Tropea, Cameron

    2007-11-01

    We report on experiments concerning unsteady effects in flapping flight, conducted in the low-speed wind tunnel of the TU Darmstadt using a mechanical flapping-wing model. Particle Image Velocimetry (PIV) was used for qualitative and quantitative analysis parallel and perpendicular to the flow field. A sensitivity analysis of the main flight parameters has been performed, with specific attention to the flight envelope of 26,500 dynamic stall effect could be verified by the direct force measurement as well as the flow visualization. The observation of the leading-edge vortex for typical bird flight reduced frequencies shows that this flow cannot be approximated as being quasi- steady. This in effect proves that adaptive wings are necessary to fully control these unsteady flow features, such as dynamic stall.

  13. Determination of the Stability and Control Characteristics of a Straight-Wing, Tailless Fighter-Airplane Model in the Langley Free-Flight Tunenl

    Science.gov (United States)

    1946-02-01

    FLIGHT TUNNEL Jr. end HermanO . Ankenbruck hngley MemorialAeronauticalLaboratory -G. ,.–. .— .. . . . . LangleyField, Va...complete model, a— .—— .- K ~“ “N&CA ACR No. L5K05 The force-test data of figures ~ and 15 show a noticeable increase in directional stabtlity with appli...Effcc+ of pwer on /ong/fud/m/ chamc+erlsfjc.sof s+u~gh{- wng, +a/1/essfighfer nzxtd k -kd m LQ@ey kee-#/9A/ “+umk+. Cen7%r-0+ gravi! 1 loc&/on, 0.048

  14. Using dataflow architecture to solve the transport lag problem when interfacing with an engineering model flight computer in a telemetry simulation

    Science.gov (United States)

    White, Joey

    The applicability of the dataflow architecture to a telemetry simulation is examined with particular reference to the problem of interfacing the simulation with an engineering model flight computer. The discussion covers the transport loop lag problem, simulation moding and control, the dataflow architecture solution, telemetry formatting and serialization, uplink command synchronization and reception, command validation and routing, and on-board computer interface and telemetry data request/response processing. The concepts discussed here have been developed for application on a training simulation for the NASA Orbital Maneuvering Vehicle.

  15. Autonomous, In-Flight Crew Health Risk Management for Exploration-Class Missions: Leveraging the Integrated Medical Model for the Exploration Medical System Demonstration Project

    Science.gov (United States)

    Butler, D. J.; Kerstman, E.; Saile, L.; Myers, J.; Walton, M.; Lopez, V.; McGrath, T.

    2011-01-01

    The Integrated Medical Model (IMM) captures organizational knowledge across the space medicine, training, operations, engineering, and research domains. IMM uses this knowledge in the context of a mission and crew profile to forecast risks to crew health and mission success. The IMM establishes a quantified, statistical relationship among medical conditions, risk factors, available medical resources, and crew health and mission outcomes. These relationships may provide an appropriate foundation for developing an in-flight medical decision support tool that helps optimize the use of medical resources and assists in overall crew health management by an autonomous crew with extremely limited interactions with ground support personnel and no chance of resupply.

  16. Stability in hovering ornithopter flight

    Science.gov (United States)

    Dietl, John M.; Garcia, Ephrahim

    2008-03-01

    The quasi-steady aerodynamics model is coupled to a dynamic model of ornithopter flight. Previously, the combined model has been used to calculate forward flight trajectories, each a limit cycle in the vehicle's states. The limit cycle results from the periodic wing beat, producing a periodic force while on the cycle's trajectory. This was accomplished using a multiple shooting algorithm and numerical integration in MATLAB. An analysis of hover, a crucial element to vertical takeoff and landing in adverse conditions, follows. A method to calculate plausible wing flapping motions and control surface deflections for hover is developed, employing the above flight dynamics model. Once a hovering limit cycle trajectory is found, it can be linearized in discrete time and analyzed for stability (by calculating the trajectory's Floquet multipliers a type of discrete-time eigenvalue) are calculated. The dynamic mode shapes are discussed.

  17. Vortex interaction of tandem pitching and plunging plates: a two-dimensional model of hovering dragonfly-like flight

    Energy Technology Data Exchange (ETDEWEB)

    Rival, David; Schoenweitz, Dirk; Tropea, Cameron, E-mail: derival@ucalgary.ca [Institute of Fluid Mechanics and Aerodynamics, Technische Universitaet Darmstadt, Darmstadt (Germany)

    2011-03-15

    The force evolution and associated vortex dynamics on a nominal two-dimensional tandem pitching and plunging configuration inspired by hovering dragonfly-like flight have been investigated experimentally using time-resolved particle image velocimetry. The aerodynamic forces acting on the flat plates have been determined using a classic control-volume approach, i.e. a momentum balance. It was found that only the tandem phasing of {psi} = 90{sup 0} was capable of generating similar levels of thrust when compared to the single-plate reference case. For this tandem configuration, however, a much more constant thrust generation was developed over the cycle. Further examination showed that the force and vortex development on the fore-plate was unaffected by the tandem configuration and that nearly all variations in performance could be attributed to the vortex interaction on the hind-plate. By calculating the trajectory and strength of the hind-plate's trailing-edge vortex, the chain-like vortex interaction mechanism responsible for improved performance at {psi} = 90{sup 0} could be identified. The underlying result from this study suggests that the dominant vortex interaction in dragonfly flight is two dimensional and that the spanwise flow generated by root-flapping kinematics is not entirely necessary for efficient propulsion but potentially due to evolutionary restrictions in nature.

  18. Vortex interaction of tandem pitching and plunging plates: a two-dimensional model of hovering dragonfly-like flight.

    Science.gov (United States)

    Rival, David; Schönweitz, Dirk; Tropea, Cameron

    2011-03-01

    The force evolution and associated vortex dynamics on a nominal two-dimensional tandem pitching and plunging configuration inspired by hovering dragonfly-like flight have been investigated experimentally using time-resolved particle image velocimetry. The aerodynamic forces acting on the flat plates have been determined using a classic control-volume approach, i.e. a momentum balance. It was found that only the tandem phasing of ψ = 90° was capable of generating similar levels of thrust when compared to the single-plate reference case. For this tandem configuration, however, a much more constant thrust generation was developed over the cycle. Further examination showed that the force and vortex development on the fore-plate was unaffected by the tandem configuration and that nearly all variations in performance could be attributed to the vortex interaction on the hind-plate. By calculating the trajectory and strength of the hind-plate's trailing-edge vortex, the chain-like vortex interaction mechanism responsible for improved performance at ψ = 90° could be identified. The underlying result from this study suggests that the dominant vortex interaction in dragonfly flight is two dimensional and that the spanwise flow generated by root-flapping kinematics is not entirely necessary for efficient propulsion but potentially due to evolutionary restrictions in nature.

  19. System Identification Modeling of Rotorcraft Flight Mechanics%旋翼飞行器飞行动力学系统辨识建模算法

    Institute of Scientific and Technical Information of China (English)

    宋彦国; 孙涛

    2011-01-01

    描述了旋翼飞行器飞行力学模型的系统辨识建模算法,从旋翼飞行器飞行动力学建模的共性问题入手,首先采用机理建模的方法分析了旋翼飞行嚣主要气动部件所受气动力.考虑旋翼挥舞运动对旋翼飞行器飞行动力学特性的影响,建立了旋翼飞行器的飞行力学系统辨识参数化模型集.其次以子空间方法辨识初始飞行动力学模型,采用加权频域预报误差法获得最优模型的两步辨识方法解决旋翼飞行器这一非线性不稳定,多输入-多输出系统辨识问题,且所辨识模型与机理模型具有相同的结构.最后对样例直升机的悬停飞行状态模型辨识进行了数值与试飞试验验证,表明了方法的有效性.%Based on common characteristics of rotorcraft flight mechanics modeling, theories and algorithm of model identification are studied. Firstly, by using mechanism modeling method and considering blades flapping, the parameter identification model group is established. Secondly, in order to solve multi input and output system identification problems, a two step identification method is proposed. It identifies the initial model by subspace identification method and then the optimized model by frequency prediction error method. Finally, with this two-step identification method, the simulation and flight tests are conducted to identify the example helicopter flight mechanics model in the hover state. The result shows that the method is effective and accurate.

  20. Re-entry flight clearance

    NARCIS (Netherlands)

    Juliana, S.

    2006-01-01

    The objective of the research was to identify and evaluate promising mathematical techniques for re-entry flight clearance. To fulfil this objective, two mathematical methods were investigated and developed: μ analysis for linear models and interval analysis for both linear and non-linear model

  1. Survival of the lichen model system Circinaria gyrosa before flight to the ISS (EXPOSE R2 mission)

    Science.gov (United States)

    De la Torre Noetzel, Rosa

    Abstract Space Verification Tests (SVT) are necessary for selection of the most promising biological organisms for flight experiments in Low Earth Orbit or other space destinations: Simulation of sample assembly, exposure to expected space parameters and sample disassembly are significantly advanced by such tests, will be performed with this tests, allowing post-analysis of the exposed biological material and thus a deeper understanding of the individual and synergistic effects of space. In this work we present the results obtained with the lichen species Circinaria gyrosa after the SVT 2 run-2 tests concerning the EXPOSE-R2 Mission Preflight Test Program, performed at the planetary and space simulation facilities at DLR (Deutsches Zentrum für Luft- und Raumfahrt, Cologne, Germany) [1], from October 2013 to January 2014. This vagrant lichen species was collected at the steppic highlands of Central Spain and defined as “astrobiological model system” due to previous test at space missions (BIOPAN-6, Foton M-3) [2, 3], Therefore, C. gyrosa is part of the BIOMEX experiment (Biology and Mars Experiment, ESA) [4] which will be exposed from July 2014 to January 2016 on board of EXPOSE R2 on the International Space Station. C. gyrosa was exposed at DLR to simulated space- and Mars parameters: a) space vacuum 10-5 Pa, space UV-radiation (200-400 nm, fluence of 12 months mission = 5 x 105 kJm-2) and temperature fluctuations (-25 ºC to 10 ºC); b); Mars Simulated CO2 atmosphere, Mars pressure of 103 Pa, Mars UV-radiation (200-400 nm), and temperature fluctuations (-25 ºC to 10 ºC). In line with the lichen's well studied adaptations to harsh environmental conditions [5, 6] we observed a high recovery- and resistance capacity of C. gyrosa which was demonstrated after a 72 hours re-activation process of in the UV-Radiation and Bioclimatology Laboratories of INTA (Atmospheric Research and Instrumentation, Dept. Earth Observation). These results confirm the high survival

  2. The mechanical power requirements of avian flight.

    Science.gov (United States)

    Askew, G N; Ellerby, D J

    2007-08-22

    A major goal of flight research has been to establish the relationship between the mechanical power requirements of flight and flight speed. This relationship is central to our understanding of the ecology and evolution of bird flight behaviour. Current approaches to determining flight power have relied on a variety of indirect measurements and led to a controversy over the shape of the power-speed relationship and a lack of quantitative agreement between the different techniques. We have used a new approach to determine flight power at a range of speeds based on the performance of the pectoralis muscles. As such, our measurements provide a unique dataset for comparison with other methods. Here we show that in budgerigars (Melopsittacus undulatus) and zebra finches (Taenopygia guttata) power is modulated with flight speed, resulting in U-shaped power-speed relationship. Our measured muscle powers agreed well with a range of powers predicted using an aerodynamic model. Assessing the accuracy of mechanical power calculated using such models is essential as they are the basis for determining flight efficiency when compared to measurements of flight metabolic rate and for predicting minimum power and maximum range speeds, key determinants of optimal flight behaviour in the field.

  3. MATHEMATICAL MODEL OF THE MOTION OF A LIGHT ATTACK AIRCRAFT WITH EXTERNAL LOAD SLINGS IN THE EXTREME AREA OF FLIGHT MODES ACCORDING TO THE ANGLE OF ATTACK

    Directory of Open Access Journals (Sweden)

    A. Popov Sergey

    2017-01-01

    Full Text Available For the time being, a combat-capable trainer aircraft has already been used as a light attack aircraft. The quality of mission effectiveness evaluation depends on the degree of relevance of mathematical models used. It is known that the mis- sion efficiency is largely determined by maneuvering capabilities of the aircraft which are realized most fully in extreme angle of attack flight modes. The article presents the study of the effect of Reynolds number, angle of attack and position on the external sling on the parameters characterizing the state of separated-vortex flow, which was conducted using soft- ware complexes such as Solid Works and Ansys Fluent. There given the dependences of the observed parameters for sta- tionary and nonstationary cases of light attack aircraft movement. The article considers the influence of time constants, which characterize the response rate and delaying of separated flow development and attached flow recovery on the state of separated-vortex flow. The author mentions how the speed of angle of attack change influences lift coefficient of a light attack aircraft with external slings due to response rate and delaying of separated flow development and attached flow recovery. The article describes the mathematical model invented by the authors. This is the model of the movements of light attack aircraft with external slings within a vertical flight maneuver, considering the peculiarities of separated-vortex flow. Using this model, there has been obtained the parameters of light attack aircraft output path from the pitch using large an- gles of attack. It is demonstrated that not considering the peculiarities of the separated-vortex flow model of light attack aircraft movements leads to certain increase of height loss at the pullout of the maneuver, which accordingly makes it pos- sible to decrease the height of the beginning of the pullout.

  4. Flight Dynamics and Controls Discipline Overview

    Science.gov (United States)

    Theodore, Colin R.

    2012-01-01

    This presentation will touch topics, including but not limited to, the objectives and challenges of flight dynamics and controls that deal with the pilot and the cockpit's technology, the flight dynamics and controls discipline tasks, and the full envelope of flight dynamics modeling. In addition, the LCTR 7x10-ft wind tunnel test will also be included along with the optimal trajectories for noise abatement and its investigations on handling quality. Furthermore, previous experiments and their complying results will also be discussed.

  5. High Salt Intake Promotes Urinary Loss of Vitamin D Metabolites by Dahl Salt-Sensitive Rats in a Space Flight Model

    Science.gov (United States)

    Thierry-Palmer, M.; Cephas, S.; Sayavongsa, P.; Clark, T.; Arnaud, S. B.

    2004-01-01

    Vitamin D metabolism in the Dahl salt-sensitive (S) rat, a model of salt-induced hypertension, differs from that in the Dahl salt-resistant (R) rat. We have demonstrated that female S rats are more vulnerable than female R rats to decreases in plasma 25-hydroxyvitamin D (25-OHD) and 1,25-dihydroxyvitamin D (1,25-(OH)2D) concentrations during hind limb unloading (a space flight model). We report here on the response of the vitamin D endocrine system of S and R rats to hind limb unloading during high salt intake. Dahl female rats (9.7-week-old) were tail-suspended (hind limb unloaded) for 28 days, while fed a diet containing twice the salt in standard rat chow (2 % sodium chloride). Control rats were fed the same diet, but were not hind limb unloaded. Vitamin D metabolites were analyzed by HPLC and radioimmunoassay kits from Diasorin.

  6. High Salt Intake Promotes Urinary Loss of Vitamin D Metabolites by Dahl Salt-Sensitive Rats in a Space Flight Model

    Science.gov (United States)

    Thierry-Palmer, M.; Cephas, S.; Sayavongsa, P.; Clark, T.; Arnaud, S. B.

    2004-01-01

    Vitamin D metabolism in the Dahl salt-sensitive (S) rat, a model of salt-induced hypertension, differs from that in the Dahl salt-resistant (R) rat. We have demonstrated that female S rats are more vulnerable than female R rats to decreases in plasma 25-hydroxyvitamin D (25-OHD) and 1,25-dihydroxyvitamin D (1,25-(OH)2D) concentrations during hind limb unloading (a space flight model). We report here on the response of the vitamin D endocrine system of S and R rats to hind limb unloading during high salt intake. Dahl female rats (9.7-week-old) were tail-suspended (hind limb unloaded) for 28 days, while fed a diet containing twice the salt in standard rat chow (2 % sodium chloride). Control rats were fed the same diet, but were not hind limb unloaded. Vitamin D metabolites were analyzed by HPLC and radioimmunoassay kits from Diasorin.

  7. Temperature dependent O3 absorption cross sections for GOME, SCIAMACHY and GOME-2: I. Re-analysis of Flight Model Data and Retrieval Tests.

    Science.gov (United States)

    Chehade, Wissam; Weber, Mark; Gorshelev, Victor; Serdyuchenko, Anna; Burrows, John P.

    For a long term coverage of global O3 measurements from SCIAMACHY (SCanning Imag-ing Absorption spectroMeter for Atmospheric CHartographY), GOME1, and GOME2 (Global Ozone Monitoring Experiment), high quality absorption cross section spectra is a pre-requisite. Laboratory measurements of cross section spectra of O3 (at 203K, 223K, 243K, 273K and 293K) were performed using CATGAS (Calibration Apparatus for Trace Gas Absorption Spec-troscopy) under representative in-flight conditions with SCIAMACHY and GOME-2 spectrom-eters to obviate the need of an instrumental slit function correction. For the data acquired from the CATGAS campaigns, a re-analysis is carried out to improve the overestimation in the total O3 retrieval by SCIAMACHY and GOME2 using the flight model (FM) reference data from SCIAMACHY and GOME2, respectively, with respect to GOME1. The reanalysis attempts to re-evaluate the concatenation of ozone optical density measurements obtained from CATGAS measurements and applying new ways to absolutely calibrate the cross-.sections using absolute reference cross-section data at reference wavelengths, Finally, a satellite retrieval error analy-sis will be performed to validate the updated satellite reference cross-sections. The updated reference data can be used for combining the data from the three instruments (plus the two upcoming GOME-2) generating a consisting long-term dataset of total ozone.

  8. Immune function during space flight

    Science.gov (United States)

    Sonnenfeld, Gerald; Shearer, William T.

    2002-01-01

    It is very likely that the human immune system will be altered in astronauts exposed to the conditions of long-term space flight: isolation, containment, microgravity, radiation, microbial contamination, sleep disruption, and insufficient nutrition. In human and animal subjects flown in space, there is evidence of immune compromise, reactivation of latent virus infection, and possible development of a premalignant or malignant condition. Moreover, in ground-based space flight model investigations, there is evidence of immune compromise and reactivation of latent virus infection. All of these observations in space flight itself or in ground-based models of space flight have a strong resonance in a wealth of human pathologic conditions involving the immune system where reactivated virus infections and cancer appear as natural consequences. The clinical conditions of Epstein-Barr-driven lymphomas in transplant patients and Kaposi's sarcoma in patients with autoimmune deficiency virus come easily to mind in trying to identify these conditions. With these thoughts in mind, it is highly appropriate, indeed imperative, that careful investigations of human immunity, infection, and cancer be made by space flight researchers.

  9. Manned Flight Simulator (MFS)

    Data.gov (United States)

    Federal Laboratory Consortium — The Aircraft Simulation Division, home to the Manned Flight Simulator (MFS), provides real-time, high fidelity, hardware-in-the-loop flight simulation capabilities...

  10. 14 CFR 91.109 - Flight instruction; Simulated instrument flight and certain flight tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight instruction; Simulated instrument flight and certain flight tests. 91.109 Section 91.109 Aeronautics and Space FEDERAL AVIATION... OPERATING AND FLIGHT RULES Flight Rules General § 91.109 Flight instruction; Simulated instrument flight...

  11. White flight or flight from poverty?

    CERN Document Server

    Jego, C; Jego, Charles; Roehner, Bertrand M.

    2006-01-01

    The phenomenon of White flight is often illustrated by the case of Detroit whose population dropped from 1.80 million to 0.95 million between 1950 and 2000 while at the same time its Black and Hispanic component grew from 30 percent to 85 percent. But is this case really representative? The present paper shows that the phenomenon of White flight is in fact essentially a flight from poverty. As a confirmation, we show that the changes in White or Black populations are highly correlated which means that White flight is always paralleled by Black flight (and Hispanic flight as well). This broader interpretation of White flight accounts not only for the case of northern cities such as Cincinnati, Cleveland or Detroit, but for all population changes at county level, provided the population density is higher than a threshold of about 50 per square-kilometer which corresponds to moderately urbanized areas (as can be found in states like Indiana or Virginia for instance).

  12. Investigating Flight with a Toy Helicopter

    Science.gov (United States)

    Liebl, Michael

    2010-01-01

    Flight fascinates people of all ages. Recent advances in battery technology have extended the capabilities of model airplanes and toy helicopters. For those who have never outgrown a childhood enthusiasm for the wonders of flight, it is possible to buy inexpensive, remotely controlled planes and helicopters. A toy helicopter offers an opportunity…

  13. Post-Flight Analysis of GPSR Performance During Orion Exploration Flight Test 1

    Science.gov (United States)

    Barker, Lee; Mamich, Harvey; McGregor, John

    2016-01-01

    On 5 December 2014, the first test flight of the Orion Multi-Purpose Crew Vehicle executed a unique and challenging flight profile including an elevated re-entry velocity and steeper flight path angle to envelope lunar re-entry conditions. A new navigation system including a single frequency (L1) GPS receiver was evaluated for use as part of the redundant navigation system required for human space flight. The single frequency receiver was challenged by a highly dynamic flight environment including flight above low Earth orbit, as well as single frequency operation with ionospheric delay present. This paper presents a brief description of the GPS navigation system, an independent analysis of flight telemetry data, and evaluation of the GPSR performance, including evaluation of the ionospheric model employed to supplement the single frequency receiver. Lessons learned and potential improvements will be discussed.

  14. Nonlinear region of attraction analysis for hypersonic flight vehicles’ flight control verification

    Directory of Open Access Journals (Sweden)

    Jie Chen

    2017-05-01

    Full Text Available The stability analysis method based on region of attraction is proposed for the hypersonic flight vehicles’ flight control verification in this article. Current practice for hypersonic flight vehicles’ flight control verification is largely dependent on linear theoretical analysis and nonlinear simulation research. This problem can be improved by the nonlinear stability analysis of flight control system. Firstly, the hypersonic flight vehicles’ flight dynamic model is simplified and fitted by polynomial equation. And then the region of attraction estimation method based on V–s iteration is presented to complete the stability analysis. Finally, with the controller law, the closed-loop system stability is analyzed to verify the effectiveness of the proposed method.

  15. Orion Exploration Flight Test Post-Flight Inspection and Analysis

    Science.gov (United States)

    Miller, J. E.; Berger, E. L.; Bohl, W. E.; Christiansen, E. L.; Davis, B. A.; Deighton, K. D.; Enriquez, P. A.; Garcia, M. A.; Hyde, J. L.; Oliveras, O. M.

    2017-01-01

    The principal mechanism for developing orbital debris environment models, is to make observations of larger pieces of debris in the range of several centimeters and greater using radar and optical techniques. For particles that are smaller than this threshold, breakup and migration models of particles to returned surfaces in lower orbit are relied upon to quantify the flux. This reliance on models to derive spatial densities of particles that are of critical importance to spacecraft make the unique nature of the EFT-1's return surface a valuable metric. To this end detailed post-flight inspections have been performed of the returned EFT-1 backshell, and the inspections identified six candidate impact sites that were not present during the pre-flight inspections. This paper describes the post-flight analysis efforts to characterize the EFT-1 mission craters. This effort included ground based testing to understand small particle impact craters in the thermal protection material, the pre- and post-flight inspection, the crater analysis using optical, X-ray computed tomography (CT) and scanning electron microscope (SEM) techniques, and numerical simulations.

  16. New Theory of Flight

    Science.gov (United States)

    Hoffman, Johan; Jansson, Johan; Johnson, Claes

    2016-06-01

    We present a new mathematical theory explaining the fluid mechanics of subsonic flight, which is fundamentally different from the existing boundary layer-circulation theory by Prandtl-Kutta-Zhukovsky formed 100 year ago. The new theory is based on our new resolution of d'Alembert's paradox showing that slightly viscous bluff body flow can be viewed as zero-drag/lift potential flow modified by 3d rotational slip separation arising from a specific separation instability of potential flow, into turbulent flow with nonzero drag/lift. For a wing this separation mechanism maintains the large lift of potential flow generated at the leading edge at the price of small drag, resulting in a lift to drag quotient of size 15-20 for a small propeller plane at cruising speed with Reynolds number {Re≈ 107} and a jumbojet at take-off and landing with {Re≈ 108} , which allows flight at affordable power. The new mathematical theory is supported by computed turbulent solutions of the Navier-Stokes equations with a slip boundary condition as a model of observed small skin friction of a turbulent boundary layer always arising for {Re > 106} , in close accordance with experimental observations over the entire range of angle of attacks including stall using a few millions of mesh points for a full wing-body configuration.

  17. Integration of an Evidence Base into a Probabilistic Risk Assessment Model. The Integrated Medical Model Database: An Organized Evidence Base for Assessing In-Flight Crew Health Risk and System Design

    Science.gov (United States)

    Saile, Lynn; Lopez, Vilma; Bickham, Grandin; FreiredeCarvalho, Mary; Kerstman, Eric; Byrne, Vicky; Butler, Douglas; Myers, Jerry; Walton, Marlei

    2011-01-01

    This slide presentation reviews the Integrated Medical Model (IMM) database, which is an organized evidence base for assessing in-flight crew health risk. The database is a relational database accessible to many people. The database quantifies the model inputs by a ranking based on the highest value of the data as Level of Evidence (LOE) and the quality of evidence (QOE) score that provides an assessment of the evidence base for each medical condition. The IMM evidence base has already been able to provide invaluable information for designers, and for other uses.

  18. A novel method for the line-of-response and time-of-flight reconstruction in TOF-PET detectors based on a library of synchronized model signals

    CERN Document Server

    Moskal, P; Bednarski, T; Białas, P; Czerwiński, E; Gajos, A; Kamińska, D; Kapłon, Ł; Kochanowski, A; Korcyl, G; Kowal, J; Kowalski, P; Kozik, T; Krzemień, W; Kubicz, E; Niedźwiecki, Sz; Pałka, M; Raczyński, L; Rudy, Z; Rundel, O; Salabura, P; Sharma, N G; Silarski, M; Słomski, A; Smyrski, J; Strzelecki, A; Wieczorek, A; Wiślicki, W; Zieliński, M

    2014-01-01

    A novel method of hit time and hit position reconstruction in scintillator detectors is described. The method is based on comparison of detector signals with results stored in a library of synchronized model signals registered for a set of well-defined positions of scintillation points. The hit position is reconstructed as the one corresponding to the signal from the library which is most similar to the measurement signal. The time of the interaction is determined as a relative time between the measured signal and the most similar one in the library. A degree of similarity of measured and model signals is defined as the distance between points representing the measurement- and model-signal in the multi-dimensional measurement space. Novelty of the method lies also in the proposed way of synchronization of model signals enabling direct determination of the difference between time-of-flights (TOF) of annihilation quanta from the annihilation point to the detectors. The introduced method was validated using expe...

  19. On Global Optimal Sailplane Flight Strategy

    Science.gov (United States)

    Sander, G. J.; Litt, F. X.

    1979-01-01

    The derivation and interpretation of the necessary conditions that a sailplane cross-country flight has to satisfy to achieve the maximum global flight speed is considered. Simple rules are obtained for two specific meteorological models. The first one uses concentrated lifts of various strengths and unequal distance. The second one takes into account finite, nonuniform space amplitudes for the lifts and allows, therefore, for dolphin style flight. In both models, altitude constraints consisting of upper and lower limits are shown to be essential to model realistic problems. Numerical examples illustrate the difference with existing techniques based on local optimality conditions.

  20. Optimum Strategies for Selecting Descent Flight-Path Angles

    Science.gov (United States)

    Wu, Minghong G. (Inventor); Green, Steven M. (Inventor)

    2016-01-01

    An information processing system and method for adaptively selecting an aircraft descent flight path for an aircraft, are provided. The system receives flight adaptation parameters, including aircraft flight descent time period, aircraft flight descent airspace region, and aircraft flight descent flyability constraints. The system queries a plurality of flight data sources and retrieves flight information including any of winds and temperatures aloft data, airspace/navigation constraints, airspace traffic demand, and airspace arrival delay model. The system calculates a set of candidate descent profiles, each defined by at least one of a flight path angle and a descent rate, and each including an aggregated total fuel consumption value for the aircraft following a calculated trajectory, and a flyability constraints metric for the calculated trajectory. The system selects a best candidate descent profile having the least fuel consumption value while the fly ability constraints metric remains within aircraft flight descent flyability constraints.

  1. STUDY AND PRACTICE OF JSBSIM MODEL-BASED PRELIMINARY FLIGHT ABILITY EVALUATION SYSTEM%基于JSBSim模型飞行能力初步评估系统的研究与实践

    Institute of Scientific and Technical Information of China (English)

    岳显; 吉华; 王强; 樊刚; 王佳

    2015-01-01

    A preliminary flight ability evaluation system based on JSBSim model is developed to meet the requirement of the flight ability evaluation in pilot student recruitment and teaching.Firstly,the framework and main modules of this system are analysed.Then the data input and output of the system are depicted,and the JSBSim model and the method of using JSBSim model in the system are introduced as well.Finally,the evaluation rules and the algorithm of flight ability evaluation are detailed.The system realises the preliminary training and preliminary evaluation on the flight ability of the pilot student.It also has the reference value for flight dynamics model study and flight simulator development.%针对飞行学员招收、教学中对飞行学员飞行能力评估的需求,研发基于JSBSim模型的飞行能力初步评估系统。首先分析系统框架和主要模块,然后阐述系统的数据输入输出,介绍JSBSim模型以及调用方法,最后论述飞行能力的评估规则和算法。系统实现了对飞行学员飞行能力的初步锻炼和初步评估,对飞行动力学模型的研究和飞行模拟器的研发也具有参考价值。

  2. Monte Carlo transport model comparison with 1A GeV accelerated iron experiment: heavy-ion shielding evaluation of NASA space flight-crew foodstuff

    Science.gov (United States)

    Stephens, D. L.; Townsend, L. W.; Miller, J.; Zeitlin, C.; Heilbronn, L.

    Deep-space manned flight as a reality depends on a viable solution to the radiation problem. Both acute and chronic radiation health threats are known to exist, with solar particle events as an example of the former and galactic cosmic rays (GCR) of the latter. In this experiment Iron ions of 1A GeV are used to simulate GCR and to determine the secondary radiation field created as the GCR-like particles interact with a thick target. A NASA prepared food pantry locker was subjected to the iron beam and the secondary fluence recorded. A modified version of the Monte Carlo heavy ion transport code developed by Zeitlin at LBNL is compared with experimental fluence. The foodstuff is modeled as mixed nuts as defined by the 71 st edition of the Chemical Rubber Company (CRC) Handbook of Physics and Chemistry. The results indicate a good agreement between the experimental data and the model. The agreement between model and experiment is determined using a linear fit to ordered pairs of data. The intercept is forced to zero. The slope fit is 0.825 and the R 2 value is 0.429 over the resolved fluence region. The removal of an outlier, Z=14, gives values of 0.888 and 0.705 for slope and R 2 respectively.

  3. 78 FR 75284 - Special Conditions: Bombardier Inc., Models BD-500-1A10 and BD-500-1A11 Series Airplanes; Flight...

    Science.gov (United States)

    2013-12-11

    ... airplanes will incorporate the following novel or unusual design features: An electronic flight control...-1A11 series airplanes. These airplanes will have a novel or unusual design feature associated with an electronic flight control system that contains fly-by-wire control laws, including envelope protections,...

  4. Free-Flight-Tunnel Investigation of the Effect of Mode of Propeller Rotation upon the Lateral-Stability Characteristics of a Twin-Engine Airplane Model with Single Vertical Tails of Different Size

    Science.gov (United States)

    1943-10-01

    engines turning right hand (2) 0.tboard propoll ~r rotation, propeiler blades on bcth engines going up near the fuselago (3) Inboard propeller rotation...changes In stabll~ty oould be more readily detectodo The effect of mode of propoller rotation on the gen~ral flight characteristics of the model was

  5. Intersatellite communications optoelectronics research at the Goddard Space Flight Center

    Science.gov (United States)

    Krainak, Michael A.

    1992-01-01

    A review is presented of current optoelectronics research and development at the NASA Goddard Space Flight Center for high-power, high-bandwidth laser transmitters; high-bandwidth, high-sensitivity optical receivers; pointing, acquisition, and tracking components; and experimental and theoretical system modeling at the NASA Goddard Space Flight Center. Program hardware and space flight opportunities are presented.

  6. Bat flight: aerodynamics, kinematics and flight morphology.

    Science.gov (United States)

    Hedenström, Anders; Johansson, L Christoffer

    2015-03-01

    Bats evolved the ability of powered flight more than 50 million years ago. The modern bat is an efficient flyer and recent research on bat flight has revealed many intriguing facts. By using particle image velocimetry to visualize wake vortices, both the magnitude and time-history of aerodynamic forces can be estimated. At most speeds the downstroke generates both lift and thrust, whereas the function of the upstroke changes with forward flight speed. At hovering and slow speed bats use a leading edge vortex to enhance the lift beyond that allowed by steady aerodynamics and an inverted wing during the upstroke to further aid weight support. The bat wing and its skeleton exhibit many features and control mechanisms that are presumed to improve flight performance. Whereas bats appear aerodynamically less efficient than birds when it comes to cruising flight, they have the edge over birds when it comes to manoeuvring. There is a direct relationship between kinematics and the aerodynamic performance, but there is still a lack of knowledge about how (and if) the bat controls the movements and shape (planform and camber) of the wing. Considering the relatively few bat species whose aerodynamic tracks have been characterized, there is scope for new discoveries and a need to study species representing more extreme positions in the bat morphospace.

  7. Digital flight control research

    Science.gov (United States)

    Potter, J. E.; Stern, R. G.; Smith, T. B.; Sinha, P.

    1974-01-01

    The results of studies which were undertaken to contribute to the design of digital flight control systems, particularly for transport aircraft are presented. In addition to the overall design considerations for a digital flight control system, the following topics are discussed in detail: (1) aircraft attitude reference system design, (2) the digital computer configuration, (3) the design of a typical digital autopilot for transport aircraft, and (4) a hybrid flight simulator.

  8. Flight Mechanics/Estimation Theory Symposium, 1989

    Science.gov (United States)

    Stengle, Thomas (Editor)

    1989-01-01

    Numerous topics in flight mechanics and estimation were discussed. Satellite attitude control, quaternion estimation, orbit and attitude determination, spacecraft maneuvers, spacecraft navigation, gyroscope calibration, spacecraft rendevous, and atmospheric drag model calculations for spacecraft lifetime prediction are among the topics covered.

  9. Non-uniform hybrid strategy for architecting and modeling flight vehicle focused system-of-systems operations

    Institute of Scientific and Technical Information of China (English)

    Tian Yifeng; Liu Hu; Luo Mingqiang; Huang Jun

    2016-01-01

    To balance the contradiction between comprehensiveness of system-of-systems (SoS) description and cost of modeling and simulation, a non-uniform hybrid strategy (NUHYS) is pro-posed. NUHYS groups elements of an SoS operation into system community or relatively indepen-dent system based on contributors complexity and focus relationship according to the focus of SoS problem. Meanwhile, modeling methods are categorized based on details attention rate and dynamic attention rate, seeking for matching contributors. Taking helicopter rescue in earthquake relief as an example, the procedure of applying NUHYS and its effectiveness are verified.

  10. Comparison between artificial neural network and multilinear regression models in an evaluation of cognitive workload in a flight simulator.

    Science.gov (United States)

    Hannula, Manne; Huttunen, Kerttu; Koskelo, Jukka; Laitinen, Tomi; Leino, Tuomo

    2008-01-01

    In this study, the performances of artificial neural network (ANN) analysis and multilinear regression (MLR) model-based estimation of heart rate were compared in an evaluation of individual cognitive workload. The data comprised electrocardiography (ECG) measurements and an evaluation of cognitive load that induces psychophysiological stress (PPS), collected from 14 interceptor fighter pilots during complex simulated F/A-18 Hornet air battles. In our data, the mean absolute error of the ANN estimate was 11.4 as a visual analog scale score, being 13-23% better than the mean absolute error of the MLR model in the estimation of cognitive workload.

  11. Non-uniform hybrid strategy for architecting and modeling flight vehicle focused system-of-systems operations

    Directory of Open Access Journals (Sweden)

    Tian Yifeng

    2016-02-01

    Full Text Available To balance the contradiction between comprehensiveness of system-of-systems (SoS description and cost of modeling and simulation, a non-uniform hybrid strategy (NUHYS is proposed. NUHYS groups elements of an SoS operation into system community or relatively independent system based on contributors complexity and focus relationship according to the focus of SoS problem. Meanwhile, modeling methods are categorized based on details attention rate and dynamic attention rate, seeking for matching contributors. Taking helicopter rescue in earthquake relief as an example, the procedure of applying NUHYS and its effectiveness are verified.

  12. Image-Based Computational Fluid Dynamics in Blood Vessel Models: Toward Developing a Prognostic Tool to Assess Cardiovascular Function Changes in Prolonged Space Flights

    Science.gov (United States)

    Chatzimavroudis, George P.; Spirka, Thomas A.; Setser, Randolph M.; Myers, Jerry G.

    2004-01-01

    One of NASA's objectives is to be able to perform a complete, pre-flight, evaluation of cardiovascular changes in astronauts scheduled for prolonged space missions. Computational fluid dynamics (CFD) has shown promise as a method for estimating cardiovascular function during reduced gravity conditions. For this purpose, MRI can provide geometrical information, to reconstruct vessel geometries, and measure all spatial velocity components, providing location specific boundary conditions. The objective of this study was to investigate the reliability of MRI-based model reconstruction and measured boundary conditions for CFD simulations. An aortic arch model and a carotid bifurcation model were scanned in a 1.5T Siemens MRI scanner. Axial MRI acquisitions provided images for geometry reconstruction (slice thickness 3 and 5 mm; pixel size 1x1 and 0.5x0.5 square millimeters). Velocity acquisitions provided measured inlet boundary conditions and localized three-directional steady-flow velocity data (0.7-3.0 L/min). The vessel walls were isolated using NIH provided software (ImageJ) and lofted to form the geometric surface. Constructed and idealized geometries were imported into a commercial CFD code for meshing and simulation. Contour and vector plots of the velocity showed identical features between the MRI velocity data, the MRI-based CFD data, and the idealized-geometry CFD data, with less than 10% differences in the local velocity values. CFD results on models reconstructed from different MRI resolution settings showed insignificant differences (less than 5%). This study illustrated, quantitatively, that reliable CFD simulations can be performed with MRI reconstructed models and gives evidence that a future, subject-specific, computational evaluation of the cardiovascular system alteration during space travel is feasible.

  13. Study on the plasma proteomic profiling by using surface enhanced laser desorption ionization time of flight mass spectrometry for setting up a diagnostic model of endometriosis

    Institute of Scientific and Technical Information of China (English)

    Liu Hai-yuan; Liu Chun-yan; Leng Jin-hua; Liu Zhu-feng; Sun Da-wei; Zhu Lan; Lang Jing-he; Zheng Yan-hua; Zhang Jian-zhong

    2007-01-01

    Objective: To determine the plasma proteomic profiling by using surface enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF-MS) combined with bioinformatics for screening biomarkers of endometriosis and primarily setting up a diagnostic model of endometriosis.Method.Thirty-six patients with endometriosis diagnosed laparoscopically and thirty-five healthy controls were included in the study.Their serum were analyzed by SELDI and protein chip to generate protein profiling spectra.Student t test was used to compare the peak intensifies of the protein profiling results from the different groups.Biomarker Pattern Software was used to analyze the data between two groups and set up a diagnostic model for endometriosis.Protein profiling spectra from sixteen endometriosis patients and fifteen healthy controls were used double-blindedly to test the efficiency of the diagnostic model and generate the sensitivity and specificity of the model.Result: Fourteen abnormally expressed protein peaks were detected in the plasma of patients with endometriosis (P<0.01).The endometriosis diagnostic model was composed of three protein peaks.It correctly identified 33 of 36 patients with endometriosis and 29 of 35 controls in the training test.In the masked set 14 of 16 patients with endometriosis and 12 of 15 normal controls were correctly identified with sensitivity of 87.5% and specificity of 8o%.Conclusion: Patients with endometriosis have a unique cluster of proteins in plasma detected by SELDI.SELDI provides a new approach for screening novel biomarkers of endometriosis.Its utility in clinical practice need further study.

  14. Flight Standards Automation System -

    Data.gov (United States)

    Department of Transportation — FAVSIS supports Flight Standards Service (AFS) by maintaining their information on entities such as air carriers, air agencies, designated airmen, and check airmen....

  15. Comparison of in situ observations of air traffic emission signatures in the North Atlantic flight corridor with simulations using a Gaussian plume model

    Energy Technology Data Exchange (ETDEWEB)

    Konopka, P.; Schlager, H.; Schulte, P.; Schumann, U.; Ziereis, H. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Hagen, D.; Whitefield, P. [Missouri Univ., Rolla, MO (United States). Lab. for Cloud and Aerosol Science

    1997-12-31

    Focussed aircraft measurements including NO, NO{sub 2}, O{sub 3}, and aerosols (CN) have been carried out over the Eastern North Atlantic as part of the POLINAT (Pollution from Aircraft Emissions in the North Atlantic Flight Corridor) project to search for small and large scale signals of air traffic emissions in the corridor region. Here, the experimental data measured at cruising altitudes on November, 6, 1994 close to peak traffic hours are considered. Observed peak concentrations in small scale NO{sub x} spikes exceed background level of about 50 pptv by up to two orders of magnitude. The measured NO{sub x} concentration field is compared with simulations obtained with a plume dispersion model using collected air traffic data and wind measurements. Additionally, the measured and calculated NO/NO{sub x} ratios are considered. The comparison with the model shows that the observed (multiple-)peaks can be understood as a superposition of several aircraft plumes with ages up to 3 hours. (author) 12 refs.

  16. Evaluation of image reconstruction algorithms encompassing Time-Of-Flight and Point Spread Function modelling for quantitative cardiac PET: phantom studies.

    Science.gov (United States)

    Presotto, L; Gianolli, L; Gilardi, M C; Bettinardi, V

    2015-04-01

    To perform kinetic modelling quantification, PET dynamic data must be acquired in short frames, where different critical conditions are met. The accuracy of reconstructed images influences quantification. The added value of Time-Of-Flight (TOF) and Point Spread Function (PSF) in cardiac image reconstruction was assessed. A static phantom was used to simulate two extreme conditions: (i) the bolus passage and (ii) the steady uptake. Various count statistics and independent noise realisations were considered. A moving phantom filled with two different radionuclides was used to simulate: (i) a great range of contrasts and (ii) the cardio/respiratory motion. Analytical and iterative reconstruction (IR) algorithms also encompassing TOF and PSF modelling were evaluated. Both analytic and IR algorithms provided good results in all the evaluated conditions. The amount of bias introduced by IR was found to be limited. TOF allowed faster convergence and lower noise levels. PSF achieved near full myocardial activity recovery in static conditions. Motion degraded performances, but the addition of both TOF and PSF maintained the best overall behaviour. IR accounting for TOF and PSF can be recommended for the quantification of dynamic cardiac PET studies as they improve the results compared to analytic and standard IR.

  17. Hypersonic Flight Mechanics. [for atmospheric entry trajectories

    Science.gov (United States)

    Busemann, A.; Vinh, N. X.; Culp, R. D.

    1976-01-01

    The effects of aerodynamic forces on trajectories at orbital speeds are discussed in terms of atmospheric models. The assumptions for the model are spherical symmetry, nonrotating, and an exponential atmosphere. The equations of flight, and the performance in extra-atmospheric flight are discussed along with the return to the atmosphere, and the entry. Solutions of the exact equations using directly matched asymptotic expansions are presented.

  18. A Hybrid Heuristics for Irregular Flight Recovery

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiu-li; ZHU Jin-fu; GAO Qiang

    2010-01-01

    Adverse weather conditions, congestion at airports, and mechanical failures often disrupt regular flight schedules. The irregular flight recovery problem aims to recover these schedules through reassignments of flights and cancellations. In this article, we develop the classic resource assignment model for the irregular flight recovery problem, and a new hybrid heuristic procedure based on greedy random adaptive search procedure (GRASP) and simulated annealing algorithm is presented to solve this problem. As compared with the original GRASP method, the proposed algorithm demonstrates quite a high global optimization capability. Computational experiments on large-scale problems show that the proposed procedure is able to generate feasible revised flight schedules of good quality in less than five seconds.

  19. Transonic Aerodynamic Characteristics of a Model of a Proposed Six-Engine Hull-Type Seaplane Designed for Supersonic Flight

    Science.gov (United States)

    Wornom, Dewey E.

    1960-01-01

    Force tests of a model of a proposed six-engine hull-type seaplane were performed in the Langley 8-foot transonic pressure tunnel. The results of these tests have indicated that the model had a subsonic zero-lift drag coefficient of 0.0240 with the highest zero-lift drag coefficient slightly greater than twice the subsonic drag level. Pitchup tendencies were noted for subsonic Mach numbers at relatively high lift coefficients. Wing leading-edge droop increased the maximum lift-drag ratio approximately 8 percent at a Mach number of 0.80 but this effect was negligible at a Mach number of 0.90 and above. The configuration exhibited stable lateral characteristics over the test Mach number range.

  20. A High-Order, Linear Time-Invariant Model for Application to Higher Harmonic Control and Flight Control System Interaction

    Science.gov (United States)

    Cheng, Rendy P.; Tischler, Mark B.; Celi, Roberto

    2006-01-01

    This research describes a new methodology for the extraction of a high-order, linear time invariant model, which allows the periodicity of the helicopter response to be accurately captured. This model provides the needed level of dynamic fidelity to permit an analysis and optimization of the AFCS and HHC algorithms. The key results of this study indicate that the closed-loop HHC system has little influence on the AFCS or on the vehicle handling qualities, which indicates that the AFCS does not need modification to work with the HHC system. However, the results show that the vibration response to maneuvers must be considered during the HHC design process, and this leads to much higher required HHC loop crossover frequencies. This research also demonstrates that the transient vibration responses during maneuvers can be reduced by optimizing the closed-loop higher harmonic control algorithm using conventional control system analyses.

  1. CUCKOO SEARCH VIA LÉVY FLIGHTS FOR OPTIMIZATION OF A PHYSICALLY-BASED RUNOFF-EROSION MODEL

    Directory of Open Access Journals (Sweden)

    Celso A. G. Santos

    2012-01-01

    Full Text Available This paper aims to calibrate a physically-based, event-oriented runoff-erosion model by means of a global optimization method known as cuckoo-host co-evolution (CHC which has co-evolutionary changes incorporated into the traditional cuckoo search algorithm. The physically-based erosion model that was chosen to be optimized here is the watershed erosion simulation program (WESP, which was developed for small semiarid basins to simulate runoff and erosion processes. The optimization technique was tested with the field data collected in an experimental watershed located in a semiarid region of Brazil, and such technique showed to be effective in order to locate the optimal erosion parameter values. On the basis of these results, such values for a semiarid region are given, which could be recommended as an initial estimate for other similar areas.

  2. Electromechanical flight control actuator

    Science.gov (United States)

    1979-01-01

    The feasibility of using an electromechanical actuator (EMA) as the primary flight control equipment in aerospace flight is examined. The EMA motor design is presented utilizing improved permanent magnet materials. The necessary equipment to complete a single channel EMA using the single channel power electronics breadboard is reported. The design and development of an improved rotor position sensor/tachometer is investigated.

  3. Java for flight software

    Science.gov (United States)

    Benowitz, E.; Niessner, A.

    2003-01-01

    This work involves developing representative mission-critical spacecraft software using the Real-Time Specification for Java (RTSJ). This work currently leverages actual flight software used in the design of actual flight software in the NASA's Deep Space 1 (DSI), which flew in 1998.

  4. Acoustic Performance of Novel Fan Noise Reduction Technologies for a High Bypass Model Turbofan at Simulated Flights Conditions

    Science.gov (United States)

    Elliott, David M.; Woodward, Richard P.; Podboy, Gary G.

    2010-01-01

    Two novel fan noise reduction technologies, over the rotor acoustic treatment and soft stator vane technologies, were tested in an ultra-high bypass ratio turbofan model in the NASA Glenn Research Center s 9- by 15-Foot Low-Speed Wind Tunnel. The performance of these technologies was compared to that of the baseline fan configuration, which did not have these technologies. Sideline acoustic data and hot film flow data were acquired and are used to determine the effectiveness of the various treatments. The material used for the over the rotor treatment was foam metal and two different types were used. The soft stator vanes had several internal cavities tuned to target certain frequencies. In order to accommodate the cavities it was necessary to use a cut-on stator to demonstrate the soft vane concept.

  5. Aerodynamic flight performance in flap-gliding birds and bats.

    Science.gov (United States)

    Muijres, Florian T; Henningsson, Per; Stuiver, Melanie; Hedenström, Anders

    2012-08-07

    Many birds use a flight mode called undulating or flap-gliding flight, where they alternate between flapping and gliding phases, while only a few bats make use of such a flight mode. Among birds, flap-gliding is commonly used by medium to large species, where it is regarded to have a lower energetic cost than continuously flapping flight. Here, we introduce a novel model for estimating the energetic flight economy of flap-gliding animals, by determining the lift-to-drag ratio for flap-gliding based on empirical lift-to-drag ratio estimates for continuous flapping flight and for continuous gliding flight, respectively. We apply the model to flight performance data of the common swift (Apus apus) and of the lesser long-nosed bat (Leptonycteris yerbabuenae). The common swift is a typical flap-glider while-to the best of our knowledge-the lesser long-nosed bat does not use flap-gliding. The results show that, according to the model, the flap-gliding common swift saves up to 15% energy compared to a continuous flapping swift, and that this is primarily due to the exceptionally high lift-to-drag ratio in gliding flight relative to that in flapping flight for common swifts. The lesser long-nosed bat, on the other hand, seems not to be able to reduce energetic costs by flap-gliding. The difference in relative costs of flap-gliding flight between the common swift and the lesser long-nosed bat can be explained by differences in morphology, flight style and wake dynamics. The model presented here proves to be a valuable tool for estimating energetic flight economy in flap-gliding animals. The results show that flap-gliding flight that is naturally used by common swifts is indeed the most economic one of the two flight modes, while this is not the case for the non-flap-gliding lesser long-nosed bat.

  6. In-flight cLFV conversion. e - μ, e - τ and μ - τ in minimal extensions of the standard model with sterile fermions

    Energy Technology Data Exchange (ETDEWEB)

    Abada, A. [CNRS, Univ. Paris-Sud, Universite Paris-Saclay, Laboratoire de Physique Theorique, Orsay (France); Romeri, V. de [IFT-UAM/CSIC, Universidad Autonoma de Madrid, Departamento de Fisica Teorica and Instituto de Fisica Teorica, Madrid (Spain); Orloff, J.; Teixeira, A.M. [Laboratoire de Physique Corpusculaire, CNRS/IN2P3-UMR 6533, Aubiere (France)

    2017-05-15

    We revisit charged lepton flavour in-flight conversions, in which a beam of electrons or muons is directed onto a fixed target, e + N → μ + N, e + N → τ + N and μ + N → τ + N, focusing on elastic interactions with a nucleus N. After a general discussion of this observable, we carry a full phenomenological analysis in the framework of minimal Standard Model extensions via sterile neutrinos, with a strong emphasis on the role of the increasingly more stringent constraints arising from other (low-energy) charged lepton flavour-violation observables. Despite the potential interest of this observable, in particular in the light of certain upcoming facilities with the capability of very intense lepton beams, our study suggests that due to current bounds on three-body decays (l{sub i} → 3l{sub j}) and μ - e conversion in nuclei, the expected number of conversions in such a minimal framework is dramatically reduced. An experimental observation of such a conversion would thus signal the presence of another source of flavour violation, possibly at tree level. (orig.)

  7. Research on modeling of flight vehicle design deviations%飞行器设计偏差量建模方法研究

    Institute of Scientific and Technical Information of China (English)

    高显忠; 侯中喜; 刘建霞

    2011-01-01

    It lays an important foundation of analyzing and evaluatiyng the performance and probabilistic design of a flight vehicle that the design variables deviations and modelled and fit into a probability density function ( PDF). For normal distribution limited in fitners and mixed Gamma distribution unable to be fit test data over the whole number axis, the method using mixed Gouss distribution to fit test data into arbitzazy functions was proposed after its rational demonstration,in which the parameters in Gauss mixed distribution was estimated by expectation maximization (EM) algorithm. The general procedure was designed,and the strategy utilizing prior distribution information and controlling incremental number of branches was proposed so as to reduce computational load and ensure the fita ccuracy. Some examples were given to illustrate the effectiveness of the method. Finally,the experiment data of axis angle deviation in an flight vehicle engine was taken as an example to show the feasibility of the proposed method in engineering application.%对设计变量的偏差量进行建模,拟合偏差量服从的概率密度函数,是分析评价飞行器性能和概率设计的重要基础.针对常用分布拟合能力有限,以及混合Gamma分布无法在整个数轴上对试验数据进行拟合的问题,在论证混合Gauss分布拟合任意概率密度函数合理性的基础上,提出了利用混合Gauss分布对试验数据进行拟合,并运用期望极大化算法(EM)估计混合Gauss分布中的参数.设计了通用的拟合试验数据的流程,提出利用先验分布信息的策略和递增的分支数控制策略,以减少运算量,保证拟合精度.通过实例验证了方法的有效性,并结合时某型飞行器发动机轴线偏斜角测试数据建模的问题开展了应用研究,表明该方法在工程应用中具有可行性.

  8. Impact of Vehicle Flexibility on IRVE-II Flight Dynamics

    Science.gov (United States)

    Bose, David M.; Toniolo, Matthew D.; Cheatwood, F. M.; Hughes, Stephen J.; Dillman, Robert A.

    2011-01-01

    The Inflatable Re-entry Vehicle Experiment II (IRVE-II) successfully launched from Wallops Flight Facility (WFF) on August 17, 2009. The primary objectives of this flight test were to demonstrate inflation and re-entry survivability, assess the thermal and drag performance of the reentry vehicle, and to collect flight data for refining pre-flight design and analysis tools. Post-flight analysis including trajectory reconstruction outlined in O Keefe3 demonstrated that the IRVE-II Research Vehicle (RV) met mission objectives but also identified a few anomalies of interest to flight dynamics engineers. Most notable of these anomalies was high normal acceleration during the re-entry pressure pulse. Deflection of the inflatable aeroshell during the pressure pulse was evident in flight video and identified as the likely cause of the anomaly. This paper provides a summary of further post-flight analysis with particular attention to the impact of aeroshell flexibility on flight dynamics and the reconciliation of flight performance with pre-flight models. Independent methods for estimating the magnitude of the deflection of the aeroshell experienced on IRVE-II are discussed. The use of the results to refine models for pre-flight prediction of vehicle performance is then described.

  9. Thermal performance evaluation of the Northrop model NSC-01-0732 concentrating solar collector array at outdoor conditions. [Marshall Space Flight Center solar house test facility

    Science.gov (United States)

    1979-01-01

    The thermal efficiency of the concentrating, tracking solar collector was tested after ten months of operation at the Marshall Space Flight Center solar house. The test procedures and results are presented.

  10. Modelling the spectral response of the Swift-XRT CCD camera: Experience learnt from in-flight calibration

    CERN Document Server

    Godet, O; Abbey, A F; Osborne, J P; Cusumano, G; Pagani, C; Capalbi, M; Perri, M; Page, K L; Burrows, D N; Campana, S; Hill, J E; Kennea, J A; Moretti, A

    2008-01-01

    (Abbreviated) We show that the XRT spectral response calibration was complicated by various energy offsets in photon counting (PC) and windowed timing (WT) modes related to the way the CCD is operated in orbit (variation in temperature during observations, contamination by optical light from the sunlit Earth and increase in charge transfer inefficiency). We describe how these effects can be corrected for in the ground processing software. We show that the low-energy response, the redistribution in spectra of absorbed sources, and the modelling of the line profile have been significantly improved since launch by introducing empirical corrections in our code when it was not possible to use a physical description. We note that the increase in CTI became noticeable in June 2006 (i.e. 14 months after launch), but the evidence of a more serious degradation in spectroscopic performance (line broadening and change in the low-energy response) due to large charge traps (i.e. faults in the Si crystal) became more signif...

  11. X-1 in flight

    Science.gov (United States)

    1947-01-01

    -moving stabilizer. The flights of the X-1s opened up a new era in aviation. The first X-1 was air-launched unpowered from a Boeing B-29 Superfortress on Jan. 25, 1946. Powered flights began in December 1946. On Oct. 14, 1947, the X-1-1, piloted by Air Force Captain Charles 'Chuck' Yeager, became the first aircraft to exceed the speed of sound, reaching about 700 miles per hour (Mach 1.06) and an altitude of 43,000 feet. The number 2 X-1 was modified and redesignated the X-1E. The modifications included adding a conventional canopy, an ejection seat, a low-pressure fuel system of increased capacity, and a thinner high-speed wing. The X-1E was used to obtain in-flight data at twice the speed of sound, with particular emphasis placed on investigating the improvements achieved with the high-speed wing. These wings, made by Stanley Aircraft, were only 3 3/8-inches thick at the root and had 343 gauges installed in them to measure structural loads and aerodynamic heating. The X-1E used its rocket engine to power it up to a speed of 1,471 miles per hour (Mach 2.24) and to an altitude of 73,000 feet. Like the X-1 it was air-launched. The X-1 aircraft were almost 31 feet long and had a wingspan of 28 feet. The X-1 was built of conventional aluminum stressed-skin construction to extremely high structural standards. The X-1E was also 31 feet long but had a wingspan of only 22 feet, 10 inches. It was powered by a Reaction Motors, Inc., XLR-8-RM-5, four-chamber rocket engine. As did all X-1 rocket engines, the LR-8-RM-5 engine did not have throttle capability, but instead, depended on ignition of any one chamber or group of chambers to vary speed. There were also X-1A, X-1B, and and a short-lived X-1D models of the X-1.

  12. Magnesium and Space Flight

    Science.gov (United States)

    Smith, Scott M.; Zwart, Sara R.

    2016-01-01

    Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in astronauts before, during, and after space missions, in 43 astronauts (34 male, 9 female) on 4-6 month space flight missions. We also studied individuals participating in a ground analog of space flight, (head-down tilt bed rest, n=27, 35 +/- 7 y). We evaluated serum concentration and 24-hour urinary excretion of magnesium along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-d space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4- to 6-month space missions.

  13. PLANNING OF TRAINING AIRCRAFT FLIGHT HOURS

    Directory of Open Access Journals (Sweden)

    Visnja Vojvodić Rosenzweig

    2010-12-01

    Full Text Available Maintenance of the training aircraft causes downtime of operations and thereby reduces the operational availability, which is crucial for flight planning in a training organisation. Manual daily planning within the fleet delivers suboptimal results and often causes discontinued flight of several aircraft that have to be maintained at the same time. Optimal maintenance schedule of training aircraft can be obtained by a sliding scale method. This paper presents a mathematical model of the sliding scale formulated by a mixed integer linear problem. Allocation of flight hours is optimised by using AMPL programming language, assuring that a sufficient number of aircraft are always available for training. The model can be used by a flight dispatch department in a training organisation as a basis for optimised planning and reduction of maintenance downtime.

  14. Thermal biology of flight in a butterfly: genotype, flight metabolism, and environmental conditions.

    Science.gov (United States)

    Mattila, Anniina L K

    2015-12-01

    Knowledge of the effects of thermal conditions on animal movement and dispersal is necessary for a mechanistic understanding of the consequences of climate change and habitat fragmentation. In particular, the flight of ectothermic insects such as small butterflies is greatly influenced by ambient temperature. Here, variation in body temperature during flight is investigated in an ecological model species, the Glanville fritillary butterfly (Melitaea cinxia). Attention is paid on the effects of flight metabolism, genotypes at candidate loci, and environmental conditions. Measurements were made under a natural range of conditions using infrared thermal imaging. Heating of flight muscles by flight metabolism has been presumed to be negligible in small butterflies. However, the results demonstrate that Glanville fritillary males with high flight metabolic rate maintain elevated body temperature better during flight than males with a low rate of flight metabolism. This effect is likely to have a significant influence on the dispersal performance and fitness of butterflies and demonstrates the possible importance of intraspecific physiological variation on dispersal in other similar ectothermic insects. The results also suggest that individuals having an advantage in low ambient temperatures can be susceptible to overheating at high temperatures. Further, tolerance of high temperatures may be important for flight performance, as indicated by an association of heat-shock protein (Hsp70) genotype with flight metabolic rate and body temperature at takeoff. The dynamics of body temperature at flight and factors affecting it also differed significantly between female and male butterflies, indicating that thermal dynamics are governed by different mechanisms in the two sexes. This study contributes to knowledge about factors affecting intraspecific variation in dispersal-related thermal performance in butterflies and other insects. Such information is needed for predictive

  15. French Flight Test Program LEA Status

    Science.gov (United States)

    2010-09-01

    reusable . French Flight Test Program LEA Status RTO-EN-AVT-185 17 - 5 Figure 4: CAD view of LEA vehicle. The test principle consists in...Figure 8: CLEA model under test at ONERA test facility. Some parametric studies related to forebody have been carried out in order to determine a...PROPULSION: ENGINE DESIGN – INTEGRATION AND THERMAL MANAGEMENT” is focused on the French flight experiment program called “LEA”. French R&T effort

  16. Initial Flight Test of the Production Support Flight Control Computers at NASA Dryden Flight Research Center

    Science.gov (United States)

    Carter, John; Stephenson, Mark

    1999-01-01

    The NASA Dryden Flight Research Center has completed the initial flight test of a modified set of F/A-18 flight control computers that gives the aircraft a research control law capability. The production support flight control computers (PSFCC) provide an increased capability for flight research in the control law, handling qualities, and flight systems areas. The PSFCC feature a research flight control processor that is "piggybacked" onto the baseline F/A-18 flight control system. This research processor allows for pilot selection of research control law operation in flight. To validate flight operation, a replication of a standard F/A-18 control law was programmed into the research processor and flight-tested over a limited envelope. This paper provides a brief description of the system, summarizes the initial flight test of the PSFCC, and describes future experiments for the PSFCC.

  17. Neuroplasticity changes during space flight

    Science.gov (United States)

    Slenzka, K.

    Neuroplasticity refers to the ability of neurons to alter some functional property in response to alterations in input. Most of the inputs received by the brain and thus the neurons are coming from the overall sensory system. The lack of gravity during space flight or even the reduction of gravity during the planned Mars missions are and will change these inputs. The often observed "loop swimming" of some aquatic species is under discussion to be based on sensory input changes as well as the observed motion sickness of astronauts and cosmonauts. Several reports are published regarding these changes being based on alterations of general neurophysiological parameters. In this paper a summing-up of recent results obtained in the last years during space flight missions will be presented. Beside data obtained from astronauts and cosmonauts, main focus of this paper will be on animal model system data.

  18. Current and Future Flight Operating Systems

    Science.gov (United States)

    Cudmore, Alan

    2007-01-01

    This viewgraph presentation reviews the current real time operating system (RTOS) type in use with current flight systems. A new RTOS model is described, i.e. the process model. Included is a review of the challenges of migrating from the classic RTOS to the Process Model type.

  19. Flight Dynamic Modeling and Analysis for a Low speed Multimode Aircraft%一种低速复合升力飞行器飞行动力学建模与分析

    Institute of Scientific and Technical Information of China (English)

    刘凯; 高正红; 黄晶

    2014-01-01

    Considering the characteristic of a multimode aircraft which consists of a ducted fan and two tilt propellers,the flight dynamic model was developed and analyzed.The momentum theo-ry was used to build the flight dynamic model for the ducted fan.Considering the redundant prob-lems in manipulating the multimode aircraft,a rea-sonable manipulation strategy was calculated.The linear models were obtained and the longitude dy-namical stability for typical flight states were ana-lyzed in different flight models.The results show that the model contains the typical characteristic of the multimode aircraft.%针对一种由升力风扇和倾转螺旋桨组成的复合升力飞行器构型特点,建立其飞行动力学模型并进行分析研究。应用动量理论分析了升力风扇的气动力。建立了飞行器纵向动力学模型。针对飞行器飞行模式转换阶段特存的操纵冗余问题,提出了合理的配平策略,完成平衡计算。在平衡状态点线化模型,并对不同飞行模式下典型飞行状态纵向动稳定性进行分析。结果表明,系统所建立的模型能够反映该类符合升力飞行器各飞行模式的典型特征。

  20. 加权 SERVQUAL 模型的航班延误服务补救质量评价研究%A Research on Service Recovery Quality Evaluation in Flight Delay Based on Weighted SERVQUAL Model

    Institute of Scientific and Technical Information of China (English)

    孔祥芬; 王晓贝

    2014-01-01

    In flight delay and service recovery , travelers′main concern is how to get the best compensa-tion.Constructive advice is offered for airlines to improve service quality .A questionnaire survey is con-ducted among passengers using the SERVQUAL evaluation model for flight delays ′service recovery issues and a remedial service quality evaluation of flight delays is done .The results show that the tangibles are the most important part of the five attributes .And the overall results indicate that travelers are not satisfied with their services.Finally, according to these results, conclusions are reached with recommendations for airlines to improve service quality after flight delays .%介绍航班延误和服务质量评价,体现航班延误服务补救质量评价的重要性。通过对旅客的问卷调查,将加权SERVQUAL评价模型应用于航班延误服务补救问题,对航班延误进行服务补救质量评价,最后为航空公司更好地提高航班延误后的服务质量提出了较详细的建议。

  1. Flight Research Building (Hangar)

    Data.gov (United States)

    Federal Laboratory Consortium — The NASA Glenn Flight Research Building is located at the NASA Glenn Research Center with aircraft access to Cleveland Hopkins International Airport. The facility is...

  2. Hypersonic flight testing

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, W.

    1987-01-01

    This presentation is developed for people attending the University of Texas week-long short course in hypersonics. The presentation will be late in the program after the audience has been exposed to computational tehniques and ground test methods. It will attempt to show why we flight test, flight test options, what we learn from flight tests and how we use this information to improve our knowledge of hypersonics. It presupposes that our primary interest is in developing vehicles which will fly in the hypersonic flight region and not in simply developing technology for technology's sake. The material is presented in annotated vugraph form so that the author's comments on each vugraph are on the back of the preceding page. It is hoped that the comments will help reinforce the message on the vugraph.

  3. Flight Systems Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I project will develop the Flight System Monitor which will use non-intrusive electrical monitoring (NEMO). The electronic system health of...

  4. 1999 Flight Mechanics Symposium

    Science.gov (United States)

    Lynch, John P. (Editor)

    1999-01-01

    This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium held on May 18-20, 1999. Sponsored by the Guidance, Navigation and Control Center of Goddard Space Flight Center, this symposium featured technical papers on a wide range of issues related to orbit-attitude prediction, determination, and control; attitude sensor calibration; attitude determination error analysis; attitude dynamics; and orbit decay and maneuver strategy. Government, industry, and the academic community participated in the preparation and presentation of these papers.

  5. Adaptive structures flight experiments

    Science.gov (United States)

    Martin, Maurice

    The topics are presented in viewgraph form and include the following: adaptive structures flight experiments; enhanced resolution using active vibration suppression; Advanced Controls Technology Experiment (ACTEX); ACTEX program status; ACTEX-2; ACTEX-2 program status; modular control patch; STRV-1b Cryocooler Vibration Suppression Experiment; STRV-1b program status; Precision Optical Bench Experiment (PROBE); Clementine Spacecraft Configuration; TECHSAT all-composite spacecraft; Inexpensive Structures and Materials Flight Experiment (INFLEX); and INFLEX program status.

  6. Base pressure and heat transfer tests of the 0.0225-scale space shuttle plume simulation model (19-OTS) in yawed flight conditions in the NASA-Lewis 10x10-foot supersonic wind tunnel (test IH83)

    Science.gov (United States)

    Foust, J. W.

    1979-01-01

    Wind tunnel tests were performed to determine pressures, heat transfer rates, and gas recovery temperatures in the base region of a rocket firing model of the space shuttle integrated vehicle during simulated yawed flight conditions. First and second stage flight of the space shuttle were simulated by firing the main engines in conjunction with the SRB rocket motors or only the SSME's into the continuous tunnel airstream. For the correct rocket plume environment, the simulated altitude pressures were halved to maintain the rocket chamber/altitude pressure ratio. Tunnel freestream Mach numbers from 2.2 to 3.5 were simulated over an altitude range of 60 to 130 thousand feet with varying angle of attack, yaw angle, nozzle gimbal angle and SRB chamber pressure. Gas recovery temperature data derived from nine gas temperature probe runs are presented. The model configuration, instrumentation, test procedures, and data reduction are described.

  7. Flapping Wing Flight Dynamic Modeling

    Science.gov (United States)

    2011-08-22

    von Karman, T. and Burgers, J. M., Gerneral Aerodynamic Theory - Perfect Fluids , Vol. II, Julius Springer , Berlin, 1935. [24] Pesavento, U. and Wang...L., Methods of Analytical Dynamics , McGraw-Hill Book Company, New York, 1970. [34] Deng, X., Schenato, L., Wu, W. C., and Sastry, S. S., Flapping...Micro air vehicle- motivated computational biomechanics in bio ights: aerodynamics, ight dynamics and maneuvering stability, Acta Mechanica

  8. Magnesium and Space Flight.

    Science.gov (United States)

    Smith, Scott M; Zwart, Sara R

    2015-12-08

    Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD) before, during, and after 4-6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female), 35 ± 7 years old). We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4-6-month space missions.

  9. Interprofessional Flight Camp.

    Science.gov (United States)

    Alfes, Celeste M; Rowe, Amanda S

    2016-01-01

    The Dorothy Ebersbach Academic Center for Flight Nursing in Cleveland, OH, holds an annual flight camp designed for master's degree nursing students in the acute care nurse practitioner program, subspecializing in flight nursing at the Frances Payne Bolton School of Nursing at Case Western Reserve University. The weeklong interprofessional training is also open to any health care provider working in an acute care setting and focuses on critical care updates, trauma, and emergency care within the critical care transport environment. This year, 29 graduate nursing students enrolled in a master's degree program from Puerto Rico attended. Although the emergency department in Puerto Rico sees and cares for trauma patients, there is no formal trauma training program. Furthermore, the country only has 1 rotor wing air medical transport service located at the Puerto Rico Medical Center in San Juan. Flight faculty and graduate teaching assistants spent approximately 9 months planning for their participation in our 13th annual flight camp. Students from Puerto Rico were extremely pleased with the learning experiences at camp and expressed particular interest in having more training time within the helicopter flight simulator.

  10. Designing Flight Deck Procedures

    Science.gov (United States)

    Degani, Asaf; Wiener, Earl

    2005-01-01

    Three reports address the design of flight-deck procedures and various aspects of human interaction with cockpit systems that have direct impact on flight safety. One report, On the Typography of Flight- Deck Documentation, discusses basic research about typography and the kind of information needed by designers of flight deck documentation. Flight crews reading poorly designed documentation may easily overlook a crucial item on the checklist. The report surveys and summarizes the available literature regarding the design and typographical aspects of printed material. It focuses on typographical factors such as proper typefaces, character height, use of lower- and upper-case characters, line length, and spacing. Graphical aspects such as layout, color coding, fonts, and character contrast are discussed; and several cockpit conditions such as lighting levels and glare are addressed, as well as usage factors such as angular alignment, paper quality, and colors. Most of the insights and recommendations discussed in this report are transferable to paperless cockpit systems of the future and computer-based procedure displays (e.g., "electronic flight bag") in aerospace systems and similar systems that are used in other industries such as medical, nuclear systems, maritime operations, and military systems.

  11. Development of a 32-detector CdTe matrix for the SVOM ECLAIRs x/gamma camera: tests results of first flight models

    Science.gov (United States)

    Lacombe, K.; Dezalay, J.-P.; Houret, B.; Amoros, C.; Atteia, J.-L.; Aubaret, K.; Billot, M.; Bordon, S.; Cordier, B.; Delaigue, S.; Galliano, M.; Gevin, O.; Godet, O.; Gonzalez, F.; Guillemot, Ph.; Limousin, O.; Mercier, K.; Nasser, G.; Pons, R.; Rambaud, D.; Ramon, P.; Waegebaert, V.

    2016-07-01

    ECLAIRs, a 2-D coded-mask imaging camera on-board the Sino-French SVOM space mission, will detect and locate gamma-ray bursts in near real time in the 4 - 150 keV energy band in a large field of view. The design of ECLAIRs has been driven by the objective to reach an unprecedented low-energy threshold of 4 keV. The detection plane is an assembly of 6400 Schottky CdTe detectors of size 4x4x1 mm3, biased from -200V to -500V and operated at -20°C. The low-energy threshold is achieved thanks to an innovative hybrid module composed of a thick film ceramic holding 32 CdTe detectors ("Detectors Ceramics"), associated to an HTCC ceramic housing a low-noise 32-channel ASIC ("ASIC Ceramics"). We manage the coupling between Detectors Ceramics and ASIC Ceramics in order to achieve the best performance and ensure the uniformity of the detection plane. In this paper, we describe the complete hybrid XRDPIX, of which 50 flight models have been manufactured by the SAGEM company. Afterwards, we show test results obtained on Detectors Ceramics, on ASIC Ceramics and on the modules once assembled. Then, we compare and confront detectors leakage currents and ASIC ENC with the energy threshold values and FWHM measured on XRDPIX modules at the temperature of -20°C by using a calibrated radioactive source of 241Am. Finally, we study the homogeneity of the spectral properties of the 32-detector hybrid matrices and we conclude on general performance of more than 1000 detection channels which may reach the lowenergy threshold of 4 keV required for the future ECLAIRs space camera.

  12. Design and Implementation of Flight Visual Simulation System

    OpenAIRE

    Tian, Feng; Chai, Wenjian; Wang, Chuanyun; Sun, Xiaoping

    2012-01-01

    The design requirement for flight visual simulation system is studied and the overall structure and development process are proposed in this paper. Through the construction of 3D scene model library and aircraft model, the rendering and interaction of visual scene are implemented. The changes of aircraft flight attitude in visual system are controlled by real-time calculation of aircraft aerodynamic and dynamic equations and flight simulation effect is enhanced by this kind of control. Severa...

  13. Cosmic-Ray Background Flux Model based on a Gamma-Ray Large-Area Space Telescope Balloon Flight Engineering Model

    Energy Technology Data Exchange (ETDEWEB)

    Mizuno, T

    2004-09-03

    Cosmic-ray background fluxes were modeled based on existing measurements and theories and are presented here. The model, originally developed for the Gamma-ray Large Area Space Telescope (GLAST) Balloon Experiment, covers the entire solid angle (4{pi} sr), the sensitive energy range of the instrument ({approx} 10 MeV to 100 GeV) and abundant components (proton, alpha, e{sup -}, e{sup +}, {mu}{sup -}, {mu}{sup +} and gamma). It is expressed in analytic functions in which modulations due to the solar activity and the Earth geomagnetism are parameterized. Although the model is intended to be used primarily for the GLAST Balloon Experiment, model functions in low-Earth orbit are also presented and can be used for other high energy astrophysical missions. The model has been validated via comparison with the data of the GLAST Balloon Experiment.

  14. Simulation and Effectiveness Evaluation Modeling of Formation Cooperative Flight-test Based on Multi-Agent System%基于多智能体的编队协同试飞仿真与效能评估

    Institute of Scientific and Technical Information of China (English)

    夏庆军; 张安; 张耀中

    2011-01-01

    In order to debase risk and cost the formation cooperative flight-test, building simulation platform to evaluate effectiveness of flight-test was put forward. Firstly, the frame of formation cooperative flight-test simulation was modeled. Based on the frame, the structure of formation cooperative flight-test simulation was set up used Multi-Agent System (MAS) and the function of each kind of agent was ascertained. Then, the process of command transportation between command control center agent and formation agent was made certain and program flow of fighter agent was set up. Lastly, the model of effectiveness evaluation was built by Lanchester equation. The simulation about the model was carried out and the results prove the model is effective.%为了降低编队协同试飞风险和代价,提出建立编队协同试飞仿真平台对试飞的效果进行评价.首先,建立了编队协同试飞模型的总体框架.在此基础上建立了基于多智能体的编队协同试飞总体结构并明确了各类型Agent的功能.然后,确定了指挥控制中心Agent与编队Agent进行命令交互的过程并建立了编队Agent和战斗机Agent的模型.最后,建立了基于兰彻斯特理论的效能评估模型,并对设定的红蓝编队进行了仿真和分析.

  15. Use of the generalized spherical harmonic model for describing crystallographic texture in polycrystalline NiTi shape-memory alloy with time-of-flight neutron powder diffraction data

    CERN Document Server

    Sitepu, H; Dreele, R B V

    2002-01-01

    We present a feasibility study to extract quantitative texture and precise crystal structure information of polycrystalline monoclinic NiTi shape-memory alloys from a simultaneous refinement of 52 time-of-flight neutron-diffraction patterns taken in 13 orientations in the diffractometer. The multiple-data-set capabilities and the generalized spherical harmonic texture model of the GSAS program system were employed. (orig.)

  16. Integrating Space Flight Resource Management Skills into Technical Lessons for International Space Station Flight Controller Training

    Science.gov (United States)

    Baldwin, Evelyn

    2008-01-01

    The Johnson Space Center s (JSC) International Space Station (ISS) Space Flight Resource Management (SFRM) training program is designed to teach the team skills required to be an effective flight controller. It was adapted from the SFRM training given to Shuttle flight controllers to fit the needs of a "24 hours a day/365 days a year" flight controller. More recently, the length reduction of technical training flows for ISS flight controllers impacted the number of opportunities for fully integrated team scenario based training, where most SFRM training occurred. Thus, the ISS SFRM training program is evolving yet again, using a new approach of teaching and evaluating SFRM alongside of technical materials. Because there are very few models in other industries that have successfully tied team and technical skills together, challenges are arising. Despite this, the Mission Operations Directorate of NASA s JSC is committed to implementing this integrated training approach because of the anticipated benefits.

  17. Flight Software for the LADEE Mission

    Science.gov (United States)

    Cannon, Howard N.

    2015-01-01

    The Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft was launched on September 6, 2013, and completed its mission on April 17, 2014 with a directed impact to the Lunar Surface. Its primary goals were to examine the lunar atmosphere, measure lunar dust, and to demonstrate high rate laser communications. The LADEE mission was a resounding success, achieving all mission objectives, much of which can be attributed to careful planning and preparation. This paper discusses some of the highlights from the mission, and then discusses the techniques used for developing the onboard Flight Software. A large emphasis for the Flight Software was to develop it within tight schedule and cost constraints. To accomplish this, the Flight Software team leveraged heritage software, used model based development techniques, and utilized an automated test infrastructure. This resulted in the software being delivered on time and within budget. The resulting software was able to meet all system requirements, and had very problems in flight.

  18. Evaluation of Small Unmanned Aircraft Flight Trajectory Accuracy

    Directory of Open Access Journals (Sweden)

    Ramūnas Kikutis

    2014-12-01

    Full Text Available Today small unmanned aircraft are being more widely adapted for practical tasks. These tasks require high reliability and flight path accuracy. For such aircraft we have to deal with the chalenge how to compensate external factors and how to ensure the accuracy of the flight trajectory according to new regulations and standards. In this paper, new regulations for the flights of small unmanned aircraft in Lithuanian air space are discussed. Main factors, which affect errors of the autonomous flight path tracking, are discussed too. The emphasis is on the wind factor and the flight path of Dubbin’s trajectories. Research was performed with mathematical-dynamic model of UAV and it was compared with theoretical calculations. All calculations and experiments were accomplished for the circular part of Dubbin’s paths when the airplane was trimmed for circular trajectory flight in calm conditions. Further, for such flight the wind influence was analysed.

  19. DAST in Flight

    Science.gov (United States)

    1980-01-01

    The modified BQM-34 Firebee II drone with Aeroelastic Research Wing (ARW-1), a supercritical airfoil, during a 1980 research flight. The remotely-piloted vehicle, which was air launched from NASA's NB-52B mothership, participated in the Drones for Aerodynamic and Structural Testing (DAST) program which ran from 1977 to 1983. The DAST 1 aircraft (Serial #72-1557), pictured, crashed on 12 June 1980 after its right wing ripped off during a test flight near Cuddeback Dry Lake, California. The crash occurred on the modified drone's third free flight. These are the image contact sheets for each image resolution of the NASA Dryden Drones for Aerodynamic and Structural Testing (DAST) Photo Gallery. From 1977 to 1983, the Dryden Flight Research Center, Edwards, California, (under two different names) conducted the DAST Program as a high-risk flight experiment using a ground-controlled, pilotless aircraft. Described by NASA engineers as a 'wind tunnel in the sky,' the DAST was a specially modified Teledyne-Ryan BQM-34E/F Firebee II supersonic target drone that was flown to validate theoretical predictions under actual flight conditions in a joint project with the Langley Research Center, Hampton, Virginia. The DAST Program merged advances in electronic remote control systems with advances in airplane design. Drones (remotely controlled, missile-like vehicles initially developed to serve as gunnery targets) had been deployed successfully during the Vietnamese conflict as reconnaissance aircraft. After the war, the energy crisis of the 1970s led NASA to seek new ways to cut fuel use and improve airplane efficiency. The DAST Program's drones provided an economical, fuel-conscious method for conducting in-flight experiments from a remote ground site. DAST explored the technology required to build wing structures with less than normal stiffness. This was done because stiffness requires structural weight but ensures freedom from flutter-an uncontrolled, divergent oscillation of

  20. 飞行机组人为差错风险分析方法研究%Modeling and Analysis of Risk of Flight Crew Error

    Institute of Scientific and Technical Information of China (English)

    高扬; 宫一民

    2014-01-01

    提出了一个新的飞行机组人为差错风险评估方法F-HECA,识别和分析航空公司的机组人为差错风险。该方法在对机组人为差错类型进行总结和分类的基础上,选取人为差错严重度作为评价指标,将该指标中的3个变量人为差错概率、人为差错后果严重度、人为差错影响概率与灰色综合评价法结合,定量评估机组人为差错的严重度,实现机组人为差错风险评估。通过实例分析验证此方法可用于分析机组人为差错风险,为飞行训练和飞行操作手册内容的改进提供技术支持,是民航人为因素研究中可借鉴的一种方法。%Flight crew human error significantly affects the reliability and safety , and is the primary factor that results in accidents/events in aviation industry .A new method of flight crew error analysis ( Flight Crew-Human Error Criticality Analysis , F-HECA) is developed .It can be used to estimate the human er-ror occurring in cockpit , decrease the error effects of these unexpected behaviors during the flight opera-tional process , and provide valuable means to enhance human reliability and system safety for flight task . Although the existing HRA ( Human Reliability Analysis ) is able to calculate the probable occurrence of human errors , it fails to identify the potentially critical problems caused by human errors in cockpit .Hu-man error criticality is constructed as the principle for assessment in the proposed method .In evaluating the flight crew error criticality , three independent variables are used .They are the probability of human er-ror, the severity of human error consequence , and the probability of human error effect .The F-HECA is integrated with grey synthetic evaluation to solve the problem of nonlinear factor that makes practical appli-cation difficult.Then, the classification and framework of flight crew error are technically established for assessing the criticality of error in

  1. Capital Flight and Economic Performance

    OpenAIRE

    Beja, Edsel Jr.

    2007-01-01

    Capital flight aggravates resource constraints and contributes to undermine long-term economic growth. Counterfactual calculations on the Philippines suggest that capital flight contributed to lower the quality of long-term economic growth. Sustained capital flight over three decades means that capital flight had a role for the Philippines to lose the opportunities to achieve economic takeoff. Unless decisive policy actions are taken up to address enduring capital flight and manage the macroe...

  2. Recent estimates of capital flight

    OpenAIRE

    Claessens, Stijn; Naude, David

    1993-01-01

    Researchers and policymakers have in recent years paid considerable attention to the phenomenon of capital flight. Researchers have focused on four questions: What concept should be used to measure capital flight? What figure for capital flight will emerge, using this measure? Can the occurrence and magnitude of capital flight be explained by certain (economic) variables? What policy changes can be useful to reverse capital flight? The authors focus strictly on presenting estimates of capital...

  3. SR-71 flight

    Science.gov (United States)

    1990-01-01

    atmospheric particles at altitudes of 80,000 feet and above where future hypersonic aircraft will be operating. The system used six sheets of laser light projected from the bottom of one of the two 'A' models. As microscopic-sized atmospheric particles passed between the two beams, direction and speed were measured and processed into standard speed and attitude references. An earlier laser air-data collection system was successfully tested at Dryden on an F-l04 testbed. The first of a series of flights using the SR-71 as a science camera platform for the NASA Jet Propulsion Laboratory was flown in March 1993. From the nosebay of the aircraft, an upward-looking ultraviolet video camera studied a variety of celestial objects in wavelengths that are blocked to ground-based astronomers. The SR-71 has also been used in a project for researchers at the University of California-Los Angeles (UCLA) who are investigating the use of charged chlorine atoms to protect and rebuild the ozone layer. The SR-71, operating as a testbed, has been used to assist in the development of a commercial satellite-based instant wireless personal communications network, called the IRIDIUM system, under a NASA commercialization assistance program. In addition, the SR-71 has been used in a program to study ways of reducing sonic boom overpressures that are heard on the ground much like sharp thunderclaps when an aircraft exceeds the speed of sound. Data from this study could eventually lead to aircraft designs that would reduce the 'peak' of sonic booms and minimize the startle affect they produce on the ground. Instruments at precise locations on the ground recorded the sonic booms as the aircraft passed overhead at known altitudes and speeds. An F-16XL aircraft was also used in this study. It was flown behind the SR-71 to 'probe' the near-field shockwave while instrumentation recorded the pressures and other atmospheric parameters. The aircraft has also been used most recently to evaluate a new concept

  4. Range Safety Flight Elevation Limit Calculation Software

    Science.gov (United States)

    Lanzi, Raymond J

    2014-01-01

    This program was developed to fill a need within the Wallops Flight Facility workflow for automation of the development of vertical plan limit lines used by flight safety officers during the conduct of expendable launch vehicle missions. Vertical plane present-position-based destruct lines have been used by range safety organizations at numerous launch ranges to mitigate launch vehicle risks during the early phase of flight. Various ranges have implemented data submittal and processing workflows to develop these destruct lines. As such, there is significant prior art in this field. The ElLimits program was developed at NASA's Wallops Flight Facility to automate the process for developing vertical plane limit lines using current computing technologies. The ElLimits program is used to configure launch-phase range safety flight control lines for guided missiles. The name of the program derives itself from the fundamental quantity that is computed - flight elevation limits. The user specifies the extent and resolution of a grid in the vertical plane oriented along the launch azimuth. At each grid point, the program computes the maximum velocity vector flight elevation that can be permitted without endangering a specified back-range location. Vertical plane x-y limit lines that can be utilized on a present position display are derived from the flight elevation limit data by numerically propagating 'streamlines' through the grid. The failure turn and debris propagation simulation technique used by the application is common to all of its analysis options. A simulation is initialized at a vertical plane grid point chosen by the program. A powered flight failure turn is then propagated in the plane for the duration of the so-called RSO reaction time. At the end of the turn, a delta-velocity is imparted, and a ballistic trajectory is propagated to impact. While the program possesses capability for powered flight failure turn modeling, it does not require extensive user

  5. Flight Guidance System Requirements Specification

    Science.gov (United States)

    Miller, Steven P.; Tribble, Alan C.; Carlson, Timothy M.; Danielson, Eric J.

    2003-01-01

    This report describes a requirements specification written in the RSML-e language for the mode logic of a Flight Guidance System of a typical regional jet aircraft. This model was created as one of the first steps in a five-year project sponsored by the NASA Langley Research Center, Rockwell Collins Inc., and the Critical Systems Research Group of the University of Minnesota to develop new methods and tools to improve the safety of avionics designs. This model will be used to demonstrate the application of a variety of methods and techniques, including safety analysis of system and subsystem requirements, verification of key properties using theorem provers and model checkers, identification of potential sources mode confusion in system designs, partitioning of applications based on the criticality of system hazards, and autogeneration of avionics quality code. While this model is representative of the mode logic of a typical regional jet aircraft, it does not describe an actual or planned product. Several aspects of a full Flight Guidance System, such as recovery from failed sensors, have been omitted, and no claims are made regarding the accuracy or completeness of this specification.

  6. 14 CFR 121.493 - Flight time limitations: Flight engineers and flight navigators.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight time limitations: Flight engineers and flight navigators. 121.493 Section 121.493 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight...

  7. DASMAT-Delft University Aircraft Simulation Model and Analysis Tool: A Matlab/Simulink Environment for Flight Dynamics and Control Analysis

    NARCIS (Netherlands)

    Van der Linden, C.A.A.M.

    1998-01-01

    Computer Assisted Design (CAD) environments have become important devices for the design and evaluation of flight control systems. For general use, different aircraft and operational conditions should be easily implemented in such a CAD environment and it should be equipped with a set of simulation

  8. DASMAT-Delft University Aircraft Simulation Model and Analysis Tool: A Matlab/Simulink Environment for Flight Dynamics and Control Analysis

    NARCIS (Netherlands)

    Van der Linden, C.A.A.M.

    1998-01-01

    Computer Assisted Design (CAD) environments have become important devices for the design and evaluation of flight control systems. For general use, different aircraft and operational conditions should be easily implemented in such a CAD environment and it should be equipped with a set of simulation

  9. Formulation of detailed consumables management models for the development (preoperational) period of advanced space transportation system. Volume 4: Flight data file contents

    Science.gov (United States)

    Zamora, M. A.

    1976-01-01

    The contents of the Flight Data File which constitute the data required by and the data generated by the Mission Planning Processor are presented for the construction of the timeline and the determination of the consumables requirements of a given mission.

  10. Design of energy-based terrain following flight control system

    Science.gov (United States)

    Wang, Wei; Li, Aijun; Xie, Yanwu; Tan, Jian

    2006-11-01

    Historically, aircraft longitudinal control has been realized by means of two loops: flight path (the control variable is elevator displacement) and speed control (the control variable is propulsive thrust or engine power). Both the elevator and throttle control cause coupled altitude and speed response, which exerts negative effects on longitudinal flight performance of aircraft, especially for Terrain Following(TF) flight. Energy-based method can resolve coupled problem between flight speed and path by controlling total energy rate and energy distribution rate between elevator and throttle. In this paper, energy-based control method is applied to design a TF flight control system for controlling flight altitude directly. An error control method of airspeed and altitude is adopted to eliminate the stable error of the total energy control system when decoupling control. Pitch loop and pitch rate feedback loop are designed for the system to damp the oscillatory response produced by TF system. The TF flight control system structure diagram and an aircraft point-mass energy motion model including basic control loops are given and used to simulate decoupling performance of the TF fight control system. Simulation results show that the energy-based TF flight control system can decouple flight velocity and flight path angle, exactly follow planned flight path, and greatly reduce altitude error, which is between +10m and -8m.

  11. Importance of body rotation during the flight of a butterfly

    Science.gov (United States)

    Fei, Yueh-Han John; Yang, Jing-Tang

    2016-03-01

    In nature the body motion of a butterfly is clearly observed to involve periodic rotation and varied flight modes. The maneuvers of a butterfly in flight are unique. Based on the flight motion of butterflies (Kallima inachus) recorded in free flight, a numerical model of a butterfly is created to study how its flight relates to body pose; the body motion in a simulation is prescribed and tested with varied initial body angle and rotational amplitude. A butterfly rotates its body to control the direction of the vortex rings generated during flapping flight; the flight modes are found to be closely related to the body motion of a butterfly. When the initial body angle increases, the forward displacement decreases, but the upward displacement increases within a stroke. With increased rotational amplitudes, the jet flows generated by a butterfly eject more downward and further enhance the generation of upward force, according to which a butterfly executes a vertical jump at the end of the downstroke. During this jumping stage, the air relative to the butterfly is moving downward; the butterfly pitches up its body to be parallel to the flow and to decrease the projected area so as to avoid further downward force generated. Our results indicate the importance of the body motion of a butterfly in flight. The inspiration of flight controlled with body motion from the flight of a butterfly might yield an alternative way to control future flight vehicles.

  12. Importance of body rotation during the flight of a butterfly.

    Science.gov (United States)

    Fei, Yueh-Han John; Yang, Jing-Tang

    2016-03-01

    In nature the body motion of a butterfly is clearly observed to involve periodic rotation and varied flight modes. The maneuvers of a butterfly in flight are unique. Based on the flight motion of butterflies (Kallima inachus) recorded in free flight, a numerical model of a butterfly is created to study how its flight relates to body pose; the body motion in a simulation is prescribed and tested with varied initial body angle and rotational amplitude. A butterfly rotates its body to control the direction of the vortex rings generated during flapping flight; the flight modes are found to be closely related to the body motion of a butterfly. When the initial body angle increases, the forward displacement decreases, but the upward displacement increases within a stroke. With increased rotational amplitudes, the jet flows generated by a butterfly eject more downward and further enhance the generation of upward force, according to which a butterfly executes a vertical jump at the end of the downstroke. During this jumping stage, the air relative to the butterfly is moving downward; the butterfly pitches up its body to be parallel to the flow and to decrease the projected area so as to avoid further downward force generated. Our results indicate the importance of the body motion of a butterfly in flight. The inspiration of flight controlled with body motion from the flight of a butterfly might yield an alternative way to control future flight vehicles.

  13. High-Speed Wind-Tunnel Tests of a Model of the Lockheed YP-80A Airplane Including Correlation with Flight Tests and Tests of Dive-Recovery Flaps

    Science.gov (United States)

    Cleary, Joseph W.; Gray, Lyle J.

    1947-01-01

    This report contains the results of tests of a 1/3-scale model of the Lockheed YP-90A "Shooting Star" airplane and a comparison of drag, maximum lift coefficient, and elevator angle required for level flight as measured in the wind tunnel and in flight. Included in the report are the general aerodynamic characteristics of the model and of two types of dive-recovery flaps, one at several positions along the chord on the lower surface of the wing and the other on the lower surface of the fuselage. The results show good agreement between the flight and wind-tunnel measurements at all Mach numbers. The results indicate that the YP-80A is controllable in pitch by the elevators to a Mach number of at least 0.85. The fuselage dive-recovery flaps are effective for producing a climbing moment and increasing the drag at Mach numbers up to at least 0.8. The wing dive-recovery flaps are most effective for producing a climbing moment at 0.75 Mach number. At 0.85 Mach number, their effectiveness is approximately 50 percent of the maximum. The optimum position for the wing dive-recovery flaps to produce a climbing moment is at approximately 35 percent of the chord.

  14. Flight calls and orientation

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Andersen, Bent Bach; Kropp, Wibke

    2008-01-01

    flight calls was simulated by sequential computer controlled activation of five loudspeakers placed in a linear array perpendicular to the bird's migration course. The bird responded to this stimulation by changing its migratory course in the direction of that of the ‘flying conspecifics' but after about......  In a pilot experiment a European Robin, Erithacus rubecula, expressing migratory restlessness with a stable orientation, was video filmed in the dark with an infrared camera and its directional migratory activity was recorded. The flight overhead of migrating conspecifics uttering nocturnal...... 30 minutes it drifted back to its original migration course. The results suggest that songbirds migrating alone at night can use the flight calls from conspecifics as additional cues for orientation and that they may compare this information with other cues to decide what course to keep....

  15. Flight calls and orientation

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Andersen, Bent Bach; Kropp, Wibke

    2008-01-01

      In a pilot experiment a European Robin, Erithacus rubecula, expressing migratory restlessness with a stable orientation, was video filmed in the dark with an infrared camera and its directional migratory activity was recorded. The flight overhead of migrating conspecifics uttering nocturnal...... flight calls was simulated by sequential computer controlled activation of five loudspeakers placed in a linear array perpendicular to the bird's migration course. The bird responded to this stimulation by changing its migratory course in the direction of that of the ‘flying conspecifics' but after about...... 30 minutes it drifted back to its original migration course. The results suggest that songbirds migrating alone at night can use the flight calls from conspecifics as additional cues for orientation and that they may compare this information with other cues to decide what course to keep....

  16. Flight Dynamics Laboratory overview

    Science.gov (United States)

    Sandford, Thaddeus

    1986-01-01

    The Flight Dynamics Laboratory (FDL) is one of four Air Force Wright Aeronautical Laboratories (AFWAL) and part of the Aeronautical Systems Division located at Wright-Patterson AFB, Ohio. The FDL is responsible for the planning and execution of research and development programs in the areas of structures and dynamics, flight controls, vehicle equipment/subsystems, and aeromechanics. Some of the areas being researched in the four FDL divisions are as follows: large space structures (LSS) materials and controls; advanced cockpit designs; bird-strike-tolerant windshields; and hypersonic interceptor system studies. Two of the FDL divisions are actively involved in programs that deal directly with LSS control/structures interaction: the Flight Controls Division and the Structures and Dynamics Division.

  17. Surface tension dominates insect flight on fluid interfaces.

    Science.gov (United States)

    Mukundarajan, Haripriya; Bardon, Thibaut C; Kim, Dong Hyun; Prakash, Manu

    2016-03-01

    Flight on the 2D air-water interface, with body weight supported by surface tension, is a unique locomotion strategy well adapted for the environmental niche on the surface of water. Although previously described in aquatic insects like stoneflies, the biomechanics of interfacial flight has never been analysed. Here, we report interfacial flight as an adapted behaviour in waterlily beetles (Galerucella nymphaeae) which are also dexterous airborne fliers. We present the first quantitative biomechanical model of interfacial flight in insects, uncovering an intricate interplay of capillary, aerodynamic and neuromuscular forces. We show that waterlily beetles use their tarsal claws to attach themselves to the interface, via a fluid contact line pinned at the claw. We investigate the kinematics of interfacial flight trajectories using high-speed imaging and construct a mathematical model describing the flight dynamics. Our results show that non-linear surface tension forces make interfacial flight energetically expensive compared with airborne flight at the relatively high speeds characteristic of waterlily beetles, and cause chaotic dynamics to arise naturally in these regimes. We identify the crucial roles of capillary-gravity wave drag and oscillatory surface tension forces which dominate interfacial flight, showing that the air-water interface presents a radically modified force landscape for flapping wing flight compared with air.

  18. Technologies for hypersonic flight

    Science.gov (United States)

    Steinheil, Eckart; Uhse, Wolfgang

    An account is given of the technology readiness requirements of the West German Saenger II air-breathing first-stage, two-stage reusable launcher system. The present, five-year conceptual development phase will give attention to propulsion, aerothermodynamic, materials/structures, and flight guidance technology development requirements. The second, seven-year development phase will involve other West European design establishments and lead to the construction of a demonstration vehicle. Attention is presently given to the air-breathing propulsion system, and to flight-weight structural systems under consideration for both external heating and internal cryogenic tankage requirements.

  19. Radiation induced muscositis as space flight risk. Model studies on X-ray and heavy ion irradiated typical oral mucosa models; Strahlungsinduzierte Mukositis als Risiko der Raumfahrt. Modelluntersuchungen an Roentgen- und Schwerionen-bestrahlten organotypischen Mundschleimhaut-Modellen

    Energy Technology Data Exchange (ETDEWEB)

    Tschachojan, Viktoria

    2014-07-29

    Humans in exomagnetospheric space are exposed to highly energetic heavy ion radiation which can be hardly shielded. Since radiation-induced mucositis constitutes a severe complication of heavy ion radiotherapy, it would also implicate a serious medical safety risk for the crew members during prolonged space flights such as missions to Moon or Mars. For assessment of risk developing radiation-induced mucositis, three-dimensional organotypic cultures of immortalized human keratinocytes and fibroblasts were irradiated with a {sup 12}C particle beam at high energies or X-Rays. Immunofluorescence stainings were done from cryosections and radiation induced release of cytokines and chemokines was quantified by ELISA from culture supernatants. The major focuses of this study were on 4, 8, 24 and 48 hours after irradiation. The conducted analyses of our mucosa model showed many structural similarities with the native oral mucosa and authentic immunological responses to radiation exposure. Quantification of the DNA damage in irradiated mucosa models revealed about twice as many DSB after heavy-ion irradiation compared to X-rays at definite doses and time points, suggesting a higher gene toxicity of heavy ions. Nuclear factor κB activation was observed after treatment with X-rays or {sup 12}C particles. An activation of NF κB p65 in irradiated samples could not be detected. ELISA analyses showed significantly higher interleukin 6 and interleukin 8 levels after irradiation with X-rays and {sup 12}C particles compared to non-irradiated controls. However, only X-rays induced significantly higher levels of interleukin 1β. Analyses of TNF-α and IFN-γ showed no radiation-induced effects. Further analyses revealed a radiation-induced reduction in proliferation and loss of compactness in irradiated oral mucosa model, which would lead to local lesions in vivo. In this study we revealed that several pro-inflammatory markers and structural changes are induced by X-rays and heavy

  20. A Model Stitching Architecture for Continuous Full Flight-Envelope Simulation of Fixed-Wing Aircraft and Rotorcraft from Discrete Point Linear Models

    Science.gov (United States)

    2016-04-01

    aircraft mass to obtain the dimensional gravity forces: F grav = XgravYgrav Zgrav  = X̄gravȲgrav Z̄grav msim (2.45) The current simulation value ...simulation model. off-nominal An off-nominal configuration is an aircraft loading configuration with values of aircraft mass, inertia, and/or center of gravity ...CG) location that differ from the identified/baseline values . relinearize To obtain a state-space representation (and the corresponding stability

  1. Development Of Maneuvering Autopilot For Flight Tests

    Science.gov (United States)

    Menon, P. K. A.; Walker, R. A.

    1992-01-01

    Report describes recent efforts to develop automatic control system operating under supervision of pilot and making airplane follow prescribed trajectories during flight tests. Report represents additional progress on this project. Gives background information on technology of control of test-flight trajectories; presents mathematical models of airframe, engine and command-augmentation system; focuses on mathematical modeling of maneuvers; addresses design of autopilots for maneuvers; discusses numerical simulation and evaluation of results of simulation of eight maneuvers under control of simulated autopilot; and presents summary and discussion of future work.

  2. Flight Control Design for a Tailless Aircraft Using Eigenstructure Assignment

    OpenAIRE

    Clara Nieto-Wire; Kenneth Sobel

    2011-01-01

    We apply eigenstructure assignment to the design of a flight control system for a wind tunnel model of a tailless aircraft. The aircraft, known as the innovative control effectors (ICEs) aircraft, has unconventional control surfaces plus pitch and yaw thrust vectoring. We linearize the aircraft in straight and level flight at an altitude of 15,000 feet and Mach number 0.4. Then, we separately design flight control systems for the longitudinal and lateral dynamics. We use a control allocation ...

  3. Flight dynamics model and system identification of longitudinal and lateral channels for a small-scale coaxial helicopter%小型共轴式直升机纵横向动力学建模与辨识

    Institute of Scientific and Technical Information of China (English)

    聂资; 陈铭; 李仁府

    2012-01-01

    Using perturbation approach, a linearized flight dynamics model was formulated for the non-linear coaxial helicopter flight control problem. Based on mathematical parametric model of the rotorcraft, the system identification model was obtained by utilizing the input and output data of longitudinal and lateral channel in flight test. The analysis and validation of the above two models in the time domain was given by computer simulation. The stability derivatives, control derivatives and the system eigenvalues were computed for the stability analysis of the helicopter. Results show that the mathematical model can reflect the dynamic characteristics of the longitudinal and lateral channels, based on which the system identification model can be a mathematical model for autonomous flight control system design.%运用经典的叶素法和一阶谐波理论,建立了悬停状态下某小型共轴式直升机纵横向通道的理论计算模型;同时根据飞行试验中采集的直升机输入输出数据,以参数化理论模型为基础,运用系统辨识的方法得到了该机纵横向通道模型.通过计算机仿真,分别对理论计算模型和系统辨识模型进行了时域验证和分析,并比较了2种模型的稳定性导数、操纵导数及特征根,对该直升机的稳定性进行了分析.研究表明:所建立的小型共轴式直升机纵横向通道的理论计算模型能够反映该机悬停状态下纵横向通道的动态特性,以此为基础建立的系统辨识模型可以作为飞行控制系统纵横向通道控制的数学模型.

  4. Space Shuttle flight control system

    Science.gov (United States)

    Klinar, W. J.; Kubiak, E. T.; Peters, W. H.; Saldana, R. L.; Smith, E. E., Jr.; Stegall, H. W.

    1975-01-01

    The Space Shuttle is a control stabilized vehicle with control provided by an all digital, fly-by-wire flight control system. This paper gives a description of the several modes of flight control which correspond to the Shuttle mission phases. These modes are ascent flight control (including open loop first stage steering, the use of four computers operating in parallel and inertial guidance sensors), on-orbit flight control (with a discussion of reaction control, phase plane switching logic, jet selection logic, state estimator logic and OMS thrust vector control), entry flight control and TAEM (terminal area energy management to landing). Also discussed are redundancy management and backup flight control.

  5. A novel method for modeling the neutron time of flight (nTOF) detector response in current mode to inertial confinement fusion experiments.

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Alan J. [University of New Mexico, Albuquerque, NM; Cooper, Gary Wayne [University of New Mexico, Albuquerque, NM; Ruiz, Carlos L.; Chandler, Gordon Andrew; Fehl, David Lee; Hahn, Kelly Denise; Leeper, Ramon Joe; Smelser, Ruth Marie; Torres, Jose A.

    2013-09-01

    There are several machines in this country that produce short bursts of neutrons for various applications. A few examples are the Zmachine, operated by Sandia National Laboratories in Albuquerque, NM; the OMEGA Laser Facility at the University of Rochester in Rochester, NY; and the National Ignition Facility (NIF) operated by the Department of Energy at Lawrence Livermore National Laboratory in Livermore, California. They all incorporate neutron time of flight (nTOF) detectors which measure neutron yield, and the shapes of the waveforms from these detectors contain germane information about the plasma conditions that produce the neutrons. However, the signals can also be %E2%80%9Cclouded%E2%80%9D by a certain fraction of neutrons that scatter off structural components and also arrive at the detectors, thereby making analysis of the plasma conditions more difficult. These detectors operate in current mode - i.e., they have no discrimination, and all the photomultiplier anode charges are integrated rather than counted individually as they are in single event counting. Up to now, there has not been a method for modeling an nTOF detector operating in current mode. MCNPPoliMiwas developed in 2002 to simulate neutron and gammaray detection in a plastic scintillator, which produces a collision data output table about each neutron and photon interaction occurring within the scintillator; however, the postprocessing code which accompanies MCNPPoliMi assumes a detector operating in singleevent counting mode and not current mode. Therefore, the idea for this work had been born: could a new postprocessing code be written to simulate an nTOF detector operating in current mode? And if so, could this process be used to address such issues as the impact of neutron scattering on the primary signal? Also, could it possibly even identify sources of scattering (i.e., structural materials) that

  6. Flight Mechanics Symposium 1997

    Science.gov (United States)

    Walls, Donna M. (Editor)

    1997-01-01

    This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium. This symposium featured technical papers on a wide range of issues related to orbit-attitude prediction, determination, and control; attitude sensor calibration; attitude determination error analysis; attitude dynamics; and orbit decay and maneuver strategy. Government, industry, and the academic community participated in the preparation and presentation of these papers.

  7. OMV In Flight

    Science.gov (United States)

    1988-01-01

    In this 1988 artist's concept, the Orbital Maneuvering Vehicle (OMV), closes in on a satellite. As envisioned by Marshall Space Flight plarners, the OMV would be a remotely-controlled free-flying space tug which would place, rendezvous, dock, and retrieve orbital payloads.

  8. NUMERICAL SIMULATION OF INSECT FLIGHT

    Institute of Scientific and Technical Information of China (English)

    CHENG Mu-lin; MIAO Wen-bo; ZHONG Chang-sheng

    2006-01-01

    In the non-inertial coordinates attached to the model wing, the two-dimensional unsteady flow field triggered by the motion of the model wing, similar to the flapping of the insect wings, was numerically simulated. One of the advantages of our method is that it has avoided the difficulty related to the moving-boundary problem. Another advantage is that the model has three degrees of freedom and can be used to simulate arbitrary motions of a two-dimensional wing in plane only if the motion is known. Such flexibility allows us to study how insects control their flying. Our results show that there are two parameters that are possibly utilized by insects to control their flight: the phase difference between the wing translation and rotation, and the lateral amplitude of flapping along the direction perpendicular to the average flapping plane.

  9. Next Generation Flight Controller Trainer System

    Science.gov (United States)

    Arnold, Scott; Barry, Matthew R.; Benton, Isaac; Bishop, Michael M.; Evans, Steven; Harvey, Jason; King, Timothy; Martin, Jacob; Mercier, Al; Miller, Walt; Payne, Dan L.; Phu, Hanh; Thompson, James C.; Aadsen, Ron

    2008-01-01

    The Next Generation Flight Controller Trainer (NGFCT) is a relatively inexpensive system of hardware and software that provides high-fidelity training for spaceshuttle flight controllers. NGFCT provides simulations into which are integrated the behaviors of emulated space-shuttle vehicle onboard general-purpose computers (GPCs), mission-control center (MCC) displays, and space-shuttle systems as represented by high-fidelity shuttle mission simulator (SMS) mathematical models. The emulated GPC computers enable the execution of onboard binary flight-specific software. The SMS models include representations of system malfunctions that can be easily invoked. The NGFCT software has a flexible design that enables independent updating of its GPC, SMS, and MCC components.

  10. Flight Training Support Cost Model Research on the Principles of Activity-based Costing%基于作业成本原理的飞行训练保障费用模型

    Institute of Scientific and Technical Information of China (English)

    徐振刚; 陈云翔; 廖东民

    2012-01-01

    Flight training and support cost is an important part of aircraft operation and support cost and is also the emphasis and difficulty of operation and support cost estimation. Combined with the actual working condition of the aviation troops, firstly, this paper uses the basic principle of activity-based costing to divide the operation of the aviation troops flight support phase,and the cost base and cost drivers are obtained. Secondly, in the light of the multiple operations of flight support phase of military aircraft, establishes flight training support costs model on the principle of activity-based costing is established. Lastly, uses examples to illustrate its advantage than other estimation methods.%飞行训练保障费用是飞机使用保障费用中的重要组成部分,也是使用保障费用估算的重点和难点.结合目前航空兵部队实际工作情况,首先利用作业成本法的基本原理,对航空兵部队飞行保障阶段的作业进行划分,得出成本库及成本动因.其次针对军机飞行保障阶段的多种作业,建立基于作业成本法的飞行训练保障费用模型.最后通过算例说明其比其他估算方法所具备的优势.

  11. X-1A in flight with flight data superimposed

    Science.gov (United States)

    1953-01-01

    crew returned to base in satisfactory condition. Four pilots had completed 29 flights (including aborts). X-1B The Bell Aircraft Corporation X-1B was similar to the Bell X-1A except for the installation of wingtips extensions for its last three flight. The NACA portion of the X-1B flight test program was for the purpose of aerodynamic heating research, accumulating data during 1956-1958. The X-1B was fitted with special instrumentation for exploratory aerodynamic heating tests. It had over 300 thermocouples installed on it. It was the first aircraft to fly with a reaction control system, a prototype of the control system used on the X-15 and other piloted aircraft. Midway through its flight test program, the X-1B was equipped with an Reaction Motors, Inc. XLR-11-RM-9 engine which differed, from the other XLR-11s, only in having an electric spark, low-tension interrupter type ignition in place of the older high-tension type. On January 27, 1959 the X-1B was given to the Air Force Museum at Wright-Patterson Air Force Base, Ohio, for preservation and public display. This aircraft completed a total of 27 glide and powered flights made by eight USAF test pilots and two NACA test pilots. X-1C Following the X-1B was the projected X-1C, which was canceled while still in the mock-up stage. The birth of transonic and supersonic-capable aircraft like the North American F-86 Sabre and the North American F-100 Super Sabre eventually eliminated the need for the X-1C. X-1D The X-1D was the first advanced model of the X-1 family to roll from Bell Aircraft Corporation's plant. It arrived at Edwards, California, in July 1951 suspended from the bomb bay shackles of a Boeing EB-50A, (46-006) aircraft. On July 24, 1951, with Bell test pilot Jean 'Skip' Ziegler at the controls, the X-1D had the only successful flight of its career. It was an unpowered glide flight, and on landing the nose gear failed with the plane sliding to a stop. The aircraft was repaired and ready once more for flight

  12. Automated Flight Routing Using Stochastic Dynamic Programming

    Science.gov (United States)

    Ng, Hok K.; Morando, Alex; Grabbe, Shon

    2010-01-01

    Airspace capacity reduction due to convective weather impedes air traffic flows and causes traffic congestion. This study presents an algorithm that reroutes flights in the presence of winds, enroute convective weather, and congested airspace based on stochastic dynamic programming. A stochastic disturbance model incorporates into the reroute design process the capacity uncertainty. A trajectory-based airspace demand model is employed for calculating current and future airspace demand. The optimal routes minimize the total expected traveling time, weather incursion, and induced congestion costs. They are compared to weather-avoidance routes calculated using deterministic dynamic programming. The stochastic reroutes have smaller deviation probability than the deterministic counterpart when both reroutes have similar total flight distance. The stochastic rerouting algorithm takes into account all convective weather fields with all severity levels while the deterministic algorithm only accounts for convective weather systems exceeding a specified level of severity. When the stochastic reroutes are compared to the actual flight routes, they have similar total flight time, and both have about 1% of travel time crossing congested enroute sectors on average. The actual flight routes induce slightly less traffic congestion than the stochastic reroutes but intercept more severe convective weather.

  13. Space Shuttle propulsion performance reconstruction from flight data

    Science.gov (United States)

    Rogers, Robert M.

    1989-01-01

    The aplication of extended Kalman filtering to estimating Space Shuttle Solid Rocket Booster (SRB) performance, specific impulse, from flight data in a post-flight processing computer program. The flight data used includes inertial platform acceleration, SRB head pressure, and ground based radar tracking data. The key feature in this application is the model used for the SRBs, which represents a reference quasi-static internal ballistics model normalized to the propellant burn depth. Dynamic states of mass overboard and propellant burn depth are included in the filter model to account for real-time deviations from the reference model used. Aerodynamic, plume, wind and main engine uncertainties are included.

  14. Bisphosphonate ISS Flight Experiment

    Science.gov (United States)

    LeBlanc, Adrian; Matsumoto, Toshio; Jones, Jeffrey; Shapiro, Jay; Lang, Thomas; Shackleford, Linda; Smith, Scott M.; Evans, Harlan; Spector, Elizabeth; Ploutz-Snyder, Robert; Sibonga, Jean; Keyak, Joyce; Nakamura, Toshitaka; Kohri, Kenjiro; Ohshima, Hiroshi; Moralez, Gilbert

    2014-01-01

    The bisphosphonate study is a collaborative effort between the NASA and JAXA space agencies to investigate the potential for antiresorptive drugs to mitigate bone changes associated with long-duration spaceflight. Elevated bone resorption is a hallmark of human spaceflight and bed rest (common zero-G analog). We tested whether an antiresorptive drug in combination with in-flight exercise would ameliorate bone loss and hypercalcuria during longduration spaceflight. Measurements include DXA, QCT, pQCT, and urine and blood biomarkers. We have completed analysis of 7 crewmembers treated with alendronate during flight and the immediate postflight (R+exercise device (ARED) during their missions. We previously reported the pre/postflight results of crew taking alendronate during flight (Osteoporosis Int. 24:2105-2114, 2013). The purpose of this report is to present the 12-month follow-up data in the treated astronauts and to compare these results with preliminary data from untreated crewmembers exercising with ARED (ARED control) or without ARED (Pre-ARED control). Results: the table presents DXA and QCT BMD expressed as percentage change from preflight in the control astronauts (18 Pre-ARED and the current 5 ARED-1-year data not yet available) and the 7 treated subjects. As shown previously the combination of exercise plus antiresorptive is effective in preventing bone loss during flight. Bone measures for treated subjects, 1 year after return from space remain at or near baseline values. Except in one region, the treated group maintained or gained bone 1 year after flight. Biomarker data are not currently available for either control group and therefore not presented. However, data from other studies with or without ARED show elevated bone resorption and urinary Ca excretion while bisphosphonate treated subjects show decreases during flight. Comparing the two control groups suggests significant but incomplete improvement in maintaining BMD using the newer exercise

  15. Modeling and Simulation of Vehicle Scheduling in Flight Logistic Support Process%场站飞行后勤保障车辆调度建模与仿真

    Institute of Scientific and Technical Information of China (English)

    田丰; 邢清华

    2011-01-01

    Under the basis of in-depth analyzing the activities’ rules of vehicle scheduling in aviation station's flight logistic support process, Using discrete event simulation method, the vehicle scheduling model in the flight logistic vehicle support process is founded. According to an example of the different constraints of vehicle support resources, the model of vehicle support scheduling is separately simulated by the software of Arena, by comparing and analyzing the simulation results, the erected simulation model about vehicle scheduling is proved scientifically and effectively, and a new kind of scientific approach is provided for the aviation station's commander to establish the flight logistic support plan scientifically by the computer simulation.%在深入分析航空兵场站飞行后勤保障车辆组织指挥活动规律的基础上,利用离散事件系统建模仿真软件Arena,建立航空兵场站飞行后勤保障车辆调度模型.结合不同保障车辆资源约束条件下的一个实例,利用仿真软件Arena对所建立保障车辆调度模型进行了仿真.通过对仿真结果的对比分析,验证了所建保障车辆调度模型的科学性、有效性,为场站指挥员制定飞行后勤保障计划提供了一种新的科学途径.

  16. Revolution of flow structures around model wing of dragonflies in hovering flight%蜻蜓翼三维流动结构的演变

    Institute of Scientific and Technical Information of China (English)

    赖国俊; 申功炘

    2013-01-01

    To study the three dimensional flow structures around a single flapping wing of dragonflies in hovering flight for future experimental comparison with flow structures around a fore-or hind wing of dragonflies,an electromechanical flapping mechanism mounted with a model wing was used to simulate the flapping motion of a dragon wing in this experiment.Three dimensional instant flow fields around the flapping wing were measured respectively at two downstroke phases (t =0.25T,0.375T) and two upstroke phased (t =0.75T,0.875T) with the digital stereo particle image velocimetry (DSPIV) and the multi-slice phase-locked technique.Three dimensional vortex structures were visualized with the local vortex identification scheme.It also was presented that the contour lines of z component of vorticity in each spanwise measuring plane,the vortex core position of the leading edge vortex (LEV) with respect to the upper wing surface and LEV sectional circulation at each spanwise measuring position.The results show that the revolution of the three-dimensional flow structures around the dragonfly wing during its stroking.%为了与蜻蜓前后翼流动干扰的流动结构作比较,首先研究了悬停飞行状态下单个蜻蜓翼周围的三维流动结构,利用一套机电拍动翼运动模拟机构模拟了一个蜻蜓翼的拍动,使用数字体视粒子图像测速技术(DSPIV,Digital Stereo Particle Image Velocimetry)和多切面锁相技术分别测量了两个下拍拍动相位时刻(t=0.25T,0.375T)和两个上拍拍动相位时刻(t=0.75T,0.875T)蜻蜓翼周围的瞬时空间三维流场,运用局部涡识别准则中的λci准则来识别和显示了流场中的三维涡结构,还展示了蜻蜓翼各个展向测量截面中的|ωz|等值线、蜻蜓翼前缘涡的涡核线相对于蜻蜓翼上翼面的空间位置以及前缘涡在各个展向测量截面中的截面环量等.实验结果揭示了蜻蜓翼周围的三维流动结构在蜻蜓翼拍动时的演变历程.

  17. Automated ISS Flight Utilities

    Science.gov (United States)

    Offermann, Jan Tuzlic

    2016-01-01

    During my internship at NASA Johnson Space Center, I worked in the Space Radiation Analysis Group (SRAG), where I was tasked with a number of projects focused on the automation of tasks and activities related to the operation of the International Space Station (ISS). As I worked on a number of projects, I have written short sections below to give a description for each, followed by more general remarks on the internship experience. My first project is titled "General Exposure Representation EVADOSE", also known as "GEnEVADOSE". This project involved the design and development of a C++/ ROOT framework focused on radiation exposure for extravehicular activity (EVA) planning for the ISS. The utility helps mission managers plan EVAs by displaying information on the cumulative radiation doses that crew will receive during an EVA as a function of the egress time and duration of the activity. SRAG uses a utility called EVADOSE, employing a model of the space radiation environment in low Earth orbit to predict these doses, as while outside the ISS the astronauts will have less shielding from charged particles such as electrons and protons. However, EVADOSE output is cumbersome to work with, and prior to GEnEVADOSE, querying data and producing graphs of ISS trajectories and cumulative doses versus egress time required manual work in Microsoft Excel. GEnEVADOSE automates all this work, reading in EVADOSE output file(s) along with a plaintext file input by the user providing input parameters. GEnEVADOSE will output a text file containing all the necessary dosimetry for each proposed EVA egress time, for each specified EVADOSE file. It also plots cumulative dose versus egress time and the ISS trajectory, and displays all of this information in an auto-generated presentation made in LaTeX. New features have also been added, such as best-case scenarios (egress times corresponding to the least dose), interpolated curves for trajectories, and the ability to query any time in the

  18. Integrated Flight Path Planning System and Flight Control System for Unmanned Helicopters

    Directory of Open Access Journals (Sweden)

    Yu-Hsiang Lin

    2011-07-01

    Full Text Available This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS and the Flight Control System (FCS. The FPPS finds the shortest flight path by the A-Star (A* algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM.

  19. Dynamic flight stability of a bumblebee in forward flight

    Institute of Scientific and Technical Information of China (English)

    Yan Xiong; Mao Sun

    2008-01-01

    The longitudinal dynamic flight stability of a bumblebee in forward flight is studied.The method of computational fluid dynamics is used to compute the aerodynamic derivatives and the techniques of eigenvalue and eigenvector analysis are employed for solving the equations of motion.The primary findings are as the following.The forward flight of the bumblebee is not dynamically stable due to the existence of one(or two)unstable or approximately neutrally stable natural modes of motion.At hovering to medium flight speed[flight speed ue=(0-3.5)m s-1;advance ratio J=0-0.44],the flight is weakly unstable or approximately neutrally stable;at high speed(ue=4.5 m s-1;J=0.57),the flight becomes strongly unstable(initial disturbance double its value in only 3.5 wingbeats).

  20. Incremental approximate dynamic programming for nonlinear flight control design

    NARCIS (Netherlands)

    Zhou, Y.; Van Kampen, E.J.; Chu, Q.P.

    2015-01-01

    A self-learning adaptive flight control design for non-linear systems allows reliable and effective operation of flight vehicles in a dynamic environment. Approximate dynamic programming (ADP) provides a model-free and computationally effective process for designing adaptive linear optimal

  1. Fighting capital flight in Ethiopia Dawit Tadesse ABSTRACT Keywords

    African Journals Online (AJOL)

    user

    2013-06-01

    Jun 1, 2013 ... purpose of this article capital flight refers to Illegal capital flight, also known as ... that hold external assets are insulated from the effects, while the poor enjoy no such cushion. ... Figure 1.1: Triangulation Research Methodology Model ... Transfer mis-pricing: This is the manipulation of prices of cross-border.

  2. Insect Vision: A Few Tricks to Regulate Flight Altitude

    OpenAIRE

    Floreano D.; Zufferey J.-C.

    2010-01-01

    A recent study sheds new light on the visual cues used by Drosophila to regulate flight altitude. The striking similarity with previously identified steering mechanisms provides a coherent basis for novel models of vision-based flight control in insects and robots.

  3. Insect vision: a few tricks to regulate flight altitude.

    Science.gov (United States)

    Floreano, Dario; Zufferey, Jean-Christophe

    2010-10-12

    A recent study sheds new light on the visual cues used by Drosophila to regulate flight altitude. The striking similarity with previously identified steering mechanisms provides a coherent basis for novel models of vision-based flight control in insects and robots.

  4. Learning control of a flight simulator stick

    NARCIS (Netherlands)

    Velthuis, W.J.R.; de Vries, Theodorus J.A.; Vrielink, Koen H.J.; Wierda, G.J.; Borghuis, André

    1998-01-01

    Aimportant part of a flight simulator is its control loading system, which is the part that emulates the behaviour of an aircraft as experienced by the pilot through the stick. Such a system consists of a model of the aircraft that is to be simulated and a stick that is driven by an electric motor.

  5. Additive Manufacturing: From Rapid Prototyping to Flight

    Science.gov (United States)

    Prater, Tracie

    2015-01-01

    Additive manufacturing (AM) offers tremendous promise for the rocket propulsion community. Foundational work must be performed to ensure the safe performance of AM parts. Government, industry, and academia must collaborate in the characterization, design, modeling, and process control to accelerate the certification of AM parts for human-rated flight.

  6. Modular Infrastructure for Rapid Flight Software Development

    Science.gov (United States)

    Pires, Craig

    2010-01-01

    This slide presentation reviews the use of modular infrastructure to assist in the development of flight software. A feature of this program is the use of model based approach for application unique software. A review of two programs that this approach was use on are: the development of software for Hover Test Vehicle (HTV), and Lunar Atmosphere and Dust Environment Experiment (LADEE).

  7. Flight Software Math Library

    Science.gov (United States)

    McComas, David

    2013-01-01

    The flight software (FSW) math library is a collection of reusable math components that provides typical math utilities required by spacecraft flight software. These utilities are intended to increase flight software quality reusability and maintainability by providing a set of consistent, well-documented, and tested math utilities. This library only has dependencies on ANSI C, so it is easily ported. Prior to this library, each mission typically created its own math utilities using ideas/code from previous missions. Part of the reason for this is that math libraries can be written with different strategies in areas like error handling, parameters orders, naming conventions, etc. Changing the utilities for each mission introduces risks and costs. The obvious risks and costs are that the utilities must be coded and revalidated. The hidden risks and costs arise in miscommunication between engineers. These utilities must be understood by both the flight software engineers and other subsystem engineers (primarily guidance navigation and control). The FSW math library is part of a larger goal to produce a library of reusable Guidance Navigation and Control (GN&C) FSW components. A GN&C FSW library cannot be created unless a standardized math basis is created. This library solves the standardization problem by defining a common feature set and establishing policies for the library s design. This allows the libraries to be maintained with the same strategy used in its initial development, which supports a library of reusable GN&C FSW components. The FSW math library is written for an embedded software environment in C. This places restrictions on the language features that can be used by the library. Another advantage of the FSW math library is that it can be used in the FSW as well as other environments like the GN&C analyst s simulators. This helps communication between the teams because they can use the same utilities with the same feature set and syntax.

  8. Ordos Takes Flight

    Institute of Scientific and Technical Information of China (English)

    YAN WEI

    2010-01-01

    @@ China's vast hinterland has long conjured up images of rugged mountains and countrysides dotted by villages all but untouched by the hands of time. But after a recent one-hour flight west from Beijing,Anna Chennault,Chair of the Council for International Cooperation (CIC),a Washington,D.C.-based non-profit organization that helps promote development in China,found something altogether different-a city called Ordos.

  9. Simulations of Levy flights

    Energy Technology Data Exchange (ETDEWEB)

    Pantaleo, E; Pascazio, S [Dipartimento di Fisica, Universita di Bari, I-70126 Bari (Italy); Facchi, P [Istituto Nazionale di Fisica Nucleare, Sezione di Bari, I-70126 Bari (Italy)], E-mail: ester.pantaleo@ba.infn.it

    2009-07-15

    Levy flights, also known as {alpha}-stable Levy processes or heavy-tailed statistics, are becoming a commonly used tool in optics. Nonetheless, the different parametrizations and the absence of any analytic expression for the distribution functions (apart from some exceptions) makes it difficult to efficiently simulate such processes. We review and compare three algorithms for the generation of sequences of symmetric stable Levy random variables.

  10. Vortex wake and flight kinematics of a swift in cruising flight in a wind tunnel.

    Science.gov (United States)

    Henningsson, P; Spedding, G R; Hedenström, A

    2008-03-01

    In this paper we describe the flight characteristics of a swift (Apus apus) in cruising flight at three different flight speeds (8.0, 8.4 and 9.2 m s(-1)) in a low turbulence wind tunnel. The wingbeat kinematics were recorded by high-speed filming and the wake of the bird was visualized by digital particle image velocimetry (DPIV). Certain flight characteristics of the swift differ from those of previously studied species. As the flight speed increases, the angular velocity of the wingbeat remains constant, and so as the wingbeat amplitude increases, the frequency decreases accordingly, as though the flight muscles were contracting at a fixed rate. The wings are also comparatively inflexible and are flexed or retracted rather little during the upstroke. The upstroke is always aerodynamically active and this is reflected in the wake, where shedding of spanwise vorticity occurs throughout the wingbeat. Although the wake superficially resembles those of other birds in cruising flight, with a pair of trailing wingtip vortices connected by spanwise vortices, the continuous shedding of first positive vorticity during the downstroke and then negative vorticity during the upstroke suggests a wing whose circulation is gradually increasing and then decreasing during the wingbeat cycle. The wake (and implied wing aerodynamics) are not well described by discrete vortex loop models, but a new wake-based model, where incremental spanwise and streamwise variations of the wake impulse are integrated over the wingbeat, shows good agreement of the vertical momentum flux with the required weight support. The total drag was also estimated from the wake alone, and the calculated lift:drag ratio of approximately 13 for flapping flight is the highest measured yet for birds.

  11. New drag laws for flapping flight

    Science.gov (United States)

    Agre, Natalie; Zhang, Jun; Ristroph, Leif

    2014-11-01

    Classical aerodynamic theory predicts that a steadily-moving wing experiences fluid forces proportional to the square of its speed. For bird and insect flight, however, there is currently no model for how drag is affected by flapping motions of the wings. By considering simple wings driven to oscillate while progressing through the air, we discover that flapping significantly changes the magnitude of drag and fundamentally alters its scaling with speed. These measurements motivate a new aerodynamic force law that could help to understand the free-flight dynamics, control, and stability of insects and flapping-wing robots.

  12. Shaping the Flight Paramedic Program.

    Science.gov (United States)

    Davids, Neil B

    2016-01-01

    Over the past 14 years of conflict, the Department of Defense medical community has made significant strides in patient care. As the conflicts developed, many sources identified a critical gap in en route care, specifically the need for critical care trained personnel for point of injury and intrahospital transfers, as well as improved outcomes for patients who received care from critical care trained providers. As stopgap measures were implemented, the US Army instituted the Critical Care Flight Paramedic Program in order to meet this need of life saving critical care transport. Execution of both an institutional training model as well as a home station training option allows for increased numbers of personnel trained, as well as flexibility for National Guard and Army Reserve units to keep personnel in their area. The Critical Care Flight Paramedic Program's educational outcomes have been exceptional, with National Registry Paramedic pass rates well above the national average. As the program develops, recertification and sustainment of knowledge and skills will be challenges, and novel approaches and flexibility will become critical for continued success.

  13. Digital virtual flight testing and evaluation method for flight characteristics airworthiness compliance of civil aircraft based on HQRM

    Directory of Open Access Journals (Sweden)

    Fan Liu

    2015-02-01

    Full Text Available In order to incorporate airworthiness requirements for flight characteristics into the entire development cycle of electronic flight control system (EFCS equipped civil aircraft, digital virtual flight testing and evaluation method based on handling qualities rating method (HQRM is proposed. First, according to HQRM, flight characteristics airworthiness requirements of civil aircraft in EFCS failure states are determined. On this basis, digital virtual flight testing model, comprising flight task digitized model, pilot controlling model, aircraft motion and atmospheric turbulence model, is used to simulate the realistic process of a pilot controlling an airplane to perform assigned flight tasks. According to the simulation results, flight characteristics airworthiness compliance of the airplane can be evaluated relying on the relevant regulations for handling qualities (HQ rating. Finally, this method is applied to a type of passenger airplane in a typical EFCS failure state, and preliminary conclusions concerning airworthiness compliance are derived quickly. The research results of this manuscript can provide important theoretical reference for EFCS design and actual airworthiness compliance verification of civil aircraft.

  14. Digital virtual flight testing and evaluation method for flight characteristics airworthiness compliance of civil aircraft based on HQRM

    Institute of Scientific and Technical Information of China (English)

    Liu Fan; Wang Lixin; Tan Xiangsheng

    2015-01-01

    In order to incorporate airworthiness requirements for flight characteristics into the entire development cycle of electronic flight control system (EFCS) equipped civil aircraft, digital virtual flight testing and evaluation method based on handling qualities rating method (HQRM) is proposed. First, according to HQRM, flight characteristics airworthiness requirements of civil aircraft in EFCS failure states are determined. On this basis, digital virtual flight testing model, comprising flight task digitized model, pilot controlling model, aircraft motion and atmospheric tur-bulence model, is used to simulate the realistic process of a pilot controlling an airplane to perform assigned flight tasks. According to the simulation results, flight characteristics airworthiness com-pliance of the airplane can be evaluated relying on the relevant regulations for handling qualities (HQ) rating. Finally, this method is applied to a type of passenger airplane in a typical EFCS failure state, and preliminary conclusions concerning airworthiness compliance are derived quickly. The research results of this manuscript can provide important theoretical reference for EFCS design and actual airworthiness compliance verification of civil aircraft.

  15. Simulation and experimental research on line throwing rocket with flight

    Institute of Scientific and Technical Information of China (English)

    Wen-bin GU; Ming LU; Jian-qing LIU; Qin-xing DONG; Zhen-xiong WANG; Jiang-hai CHEN

    2014-01-01

    The finite segment method is used to model the line throwing rocket system. A dynamic model of line throwing rocket with flight motion based on Kane’s method is presented by the kinematics description of the system and the consideration of the forces acting on the system. The experiment designed according to the parameters of the dynamic model is made. The simulation and experiment results, such as range, velocity and flight time, are compared and analyzed. The simulation results are basically agreed with the test data, which shows that the flight motion of the line throwing rocket can be predicted by the dynamic model. A theoretical model and guide for the further research on the disturbance of rope and the guidance, flight control of line throwing rocket are provided by the dynamic modeling.

  16. The Legacy of Space Shuttle Flight Software

    Science.gov (United States)

    Hickey, Christopher J.; Loveall, James B.; Orr, James K.; Klausman, Andrew L.

    2011-01-01

    The initial goals of the Space Shuttle Program required that the avionics and software systems blaze new trails in advancing avionics system technology. Many of the requirements placed on avionics and software were accomplished for the first time on this program. Examples include comprehensive digital fly-by-wire technology, use of a digital databus for flight critical functions, fail operational/fail safe requirements, complex automated redundancy management, and the use of a high-order software language for flight software development. In order to meet the operational and safety goals of the program, the Space Shuttle software had to be extremely high quality, reliable, robust, reconfigurable and maintainable. To achieve this, the software development team evolved a software process focused on continuous process improvement and defect elimination that consistently produced highly predictable and top quality results, providing software managers the confidence needed to sign each Certificate of Flight Readiness (COFR). This process, which has been appraised at Capability Maturity Model (CMM)/Capability Maturity Model Integration (CMMI) Level 5, has resulted in one of the lowest software defect rates in the industry. This paper will present an overview of the evolution of the Primary Avionics Software System (PASS) project and processes over thirty years, an argument for strong statistical control of software processes with examples, an overview of the success story for identifying and driving out errors before flight, a case study of the few significant software issues and how they were either identified before flight or slipped through the process onto a flight vehicle, and identification of the valuable lessons learned over the life of the project.

  17. Design and Testing of Flight Control Laws on the RASCAL Research Helicopter

    Science.gov (United States)

    Frost, Chad R.; Hindson, William S.; Moralez. Ernesto, III; Tucker, George E.; Dryfoos, James B.

    2001-01-01

    Two unique sets of flight control laws were designed, tested and flown on the Army/NASA Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) JUH-60A Black Hawk helicopter. The first set of control laws used a simple rate feedback scheme, intended to facilitate the first flight and subsequent flight qualification of the RASCAL research flight control system. The second set of control laws comprised a more sophisticated model-following architecture. Both sets of flight control laws were developed and tested extensively using desktop-to-flight modeling, analysis, and simulation tools. Flight test data matched the model predicted responses well, providing both evidence and confidence that future flight control development for RASCAL will be efficient and accurate.

  18. A benchmark for fault tolerant flight control evaluation

    Science.gov (United States)

    Smaili, H.; Breeman, J.; Lombaerts, T.; Stroosma, O.

    2013-12-01

    A large transport aircraft simulation benchmark (REconfigurable COntrol for Vehicle Emergency Return - RECOVER) has been developed within the GARTEUR (Group for Aeronautical Research and Technology in Europe) Flight Mechanics Action Group 16 (FM-AG(16)) on Fault Tolerant Control (2004 2008) for the integrated evaluation of fault detection and identification (FDI) and reconfigurable flight control strategies. The benchmark includes a suitable set of assessment criteria and failure cases, based on reconstructed accident scenarios, to assess the potential of new adaptive control strategies to improve aircraft survivability. The application of reconstruction and modeling techniques, based on accident flight data, has resulted in high-fidelity nonlinear aircraft and fault models to evaluate new Fault Tolerant Flight Control (FTFC) concepts and their real-time performance to accommodate in-flight failures.

  19. Loads in the design of flight vehicles

    Directory of Open Access Journals (Sweden)

    Simion TĂTARU

    2010-09-01

    Full Text Available The calculation of flight loads is a critical part of air vehicle design. On the other hand, the prediction of accurate loads is a sophisticated and complex process that requires skilled and experienced engineers. They must integrate results from wind tunnel tests, computer simulations, historical data and empirical formulations into a number of loads cases that provide a realistic assessment of the flight vehicle’s environment. Under these conditions, the vehicle must satisfy requirements imposed by regulatory agencies as part of the vehicle certification process.Loads and boundary conditions can be associated to either the finite element model or the underlying geometry. By associating loads and boundary conditions to the geometry the finite element model mesh and elements can be modified without redefining and applying the loads to the model. Loads and boundary conditions are associated to the model geometry by default.

  20. Modeling and characteristics of bending vibration for helicopter tail drive shaft during maneuver flight%机动飞行时直升机尾传动轴的横向振动建模与特性

    Institute of Scientific and Technical Information of China (English)

    倪德; 朱如鹏; 靳广虎; 李发家

    2014-01-01

    提出了直升机空间机动飞行及尾传动轴运动位姿的一种描述方法,建立了相关坐标系。基于扩展哈密顿原理,建立了直升机空间机动飞行下尾斜轴横向弯曲振动的动力学模型,并利用伽辽金法将偏微分方程转化为常微分方程。水平传动轴可以当作尾斜轴的一种特例,通过一坐标变换矩阵即可将尾斜轴的动力学方程变换为水平传动轴的动力学方程。分析了直升机空间机动飞行对尾传动轴横向弯曲振动特性的影响。结果表明:直升机的机动飞行会对尾传动轴的横向弯曲振动产生附加的刚度效应、阻尼效应和激励效应,使得传动轴轨迹中心的位置和运动轨道的大小发生改变。%A description method for spatial motions of helicopter maneuver flight and helicopter tail drive shaft was proposed and the corresponding coordinate systems were established.A lateral bending vibration model of the helicopter oblique tail drive shaft during maneuvering flight was established by using the extended Hamilton's principle,and the partial differential equations were converted into the ordinary differential ones by using Galerkin method.A horizontal shaft could be regarded as a special case of an oblique tail shaft,and the dynamic equations of the oblique tail drive shaft could be converted into those of a horizontal drive shaft by using a coordinate transformation matrix.The effects of spatial maneuver flight on the vibration characteristics of the tail drive shaft were discussed with the combination of mathematical model and numerical simulation.The study results revealed that the spatial maneuver flight of a helicopter can produce additional stiffness effect,damping effect and external excitation force effect on the bending vibration of the helicopter tail drive shoft,they may change the center position and the size of the motion orbit of the tail drive shaft.

  1. The Aerodynamics of Frisbee Flight

    Directory of Open Access Journals (Sweden)

    Kathleen Baumback

    2010-01-01

    Full Text Available This project will describe the physics of a common Frisbee in flight. The aerodynamic forces acting on the Frisbee are lift and drag, with lift being explained by Bernoulli‘s equation and drag by the Prandtl relationship. Using V. R. Morrison‘s model for the 2-dimensional trajectory of a Frisbee, equations for the x- and y- components of the Frisbee‘s motion were written in Microsoft Excel and the path of the Frisbee was illustrated. Variables such as angle of attack, area, and attack velocity were altered to see their effect on the Frisbee‘s path and to speculate on ways to achieve maximum distance and height.

  2. Orion Pad Abort 1 Flight Test - Ground and Flight Operations

    Science.gov (United States)

    Hackenbergy, Davis L.; Hicks, Wayne

    2011-01-01

    This paper discusses the ground and flight operations aspects to the Pad Abort 1 launch. The paper details the processes used to plan all operations. The paper then discussions the difficulties of integration and testing, while detailing some of the lessons learned throughout the entire launch campaign. Flight operational aspects of the launc are covered in order to provide the listener with the full suite of operational issues encountered in preparation for the first flight test of the Orion Launch Abort System.

  3. Flight Mechanics Project

    Science.gov (United States)

    Steck, Daniel

    2009-01-01

    This report documents the generation of an outbound Earth to Moon transfer preliminary database consisting of four cases calculated twice a day for a 19 year period. The database was desired as the first step in order for NASA to rapidly generate Earth to Moon trajectories for the Constellation Program using the Mission Assessment Post Processor. The completed database was created running a flight trajectory and optimization program, called Copernicus, in batch mode with the use of newly created Matlab functions. The database is accurate and has high data resolution. The techniques and scripts developed to generate the trajectory information will also be directly used in generating a comprehensive database.

  4. The wake of hovering flight in bats

    Science.gov (United States)

    Håkansson, Jonas; Hedenström, Anders; Winter, York; Johansson, L. Christoffer

    2015-01-01

    Hovering means stationary flight at zero net forward speed, which can be achieved by animals through muscle powered flapping flight. Small bats capable of hovering typically do so with a downstroke in an inclined stroke plane, and with an aerodynamically active outer wing during the upstroke. The magnitude and time history of aerodynamic forces should be reflected by vorticity shed into the wake. We thus expect hovering bats to generate a characteristic wake, but this has until now never been studied. Here we trained nectar-feeding bats, Leptonycteris yerbabuenae, to hover at a feeder and using time-resolved stereoscopic particle image velocimetry in conjunction with high-speed kinematic analysis we show that hovering nectar-feeding bats produce a series of bilateral stacked vortex loops. Vortex visualizations suggest that the downstroke produces the majority of the weight support, but that the upstroke contributes positively to the lift production. However, the relative contributions from downstroke and upstroke could not be determined on the basis of the wake, because wake elements from down- and upstroke mix and interact. We also use a modified actuator disc model to estimate lift force, power and flap efficiency. Based on our quantitative wake-induced velocities, the model accounts for weight support well (108%). Estimates of aerodynamic efficiency suggest hovering flight is less efficient than forward flapping flight, while the overall energy conversion efficiency (mechanical power output/metabolic power) was estimated at 13%. PMID:26179990

  5. Numerical study of insect free hovering flight

    Science.gov (United States)

    Wu, Di; Yeo, Khoon Seng; Lim, Tee Tai; Fluid lab, Mechanical Engineering, National University of Singapore Team

    2012-11-01

    In this paper we present the computational fluid dynamics study of three-dimensional flow field around a free hovering fruit fly integrated with unsteady FSI analysis and the adaptive flight control system for the first time. The FSI model being specified for fruitfly hovering is achieved by coupling a structural problem based on Newton's second law with a rigorous CFD solver concerning generalized finite difference method. In contrast to the previous hovering flight research, the wing motion employed here is not acquired from experimental data but governed by our proposed control systems. Two types of hovering control strategies i.e. stroke plane adjustment mode and paddling mode are explored, capable of generating the fixed body position and orientation characteristic of hovering flight. Hovering flight associated with multiple wing kinematics and body orientations are shown as well, indicating the means by which fruitfly actually maintains hovering may have considerable freedom and therefore might be influenced by many other factors beyond the physical and aerodynamic requirements. Additionally, both the near- and far-field flow and vortex structure agree well with the results from other researchers, demonstrating the reliability of our current model.

  6. Eclipse - tow flight closeup and release

    Science.gov (United States)

    1998-01-01

    flight brought the project to a successful completion. Preliminary flight results determined that the handling qualities of the QF-106 on tow were very stable; actual flight-measured values of tow rope tension were well within predictions made by the simulation, aerodynamic characteristics and elastic properties of the tow rope were a significant component of the towing system; and the Dryden high-fidelity simulation provided a representative model of the performance of the QF-106 and C-141A airplanes in tow configuration. Total time on tow for the entire project was 5 hours, 34 minutes, and 29 seconds. All six flights were highly productive, and all project objectives were achieved. All three of the project objectives were successfully accomplished. The objectives were: demonstration of towed takeoff, climb-out, and separation of the EXD-01 from the towing aircraft; validation of simulation models of the towed aircraft systems; and development of ground and flight procedures for towing and launching a delta-winged airplane configuration safely behind a transport-type aircraft. NASA Dryden served as the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden also supplied engineering, simulation, instrumentation, range support, research pilots, and chase aircraft for the test series. Dryden personnel also performed the modifications to convert the QF-106 into the piloted EXD-01 aircraft. During the early flight phase of the project, Tracor, Inc. provided maintenance and ground support for the two QF-106 airplanes.The Air Force Flight Test Center (AFFTC), Edwards, California, provided the C-141A transport aircraft for the project, its flight and engineering support, and the aircrew. Kelly Space and Technology provided the modification design and fabrication of the hardware that was installed on the EXD-01 aircraft. Kelly Space and Technology hopes to use the data gleaned from the tow tests to develop a series of low-cost reusable

  7. 14 CFR 125.297 - Approval of flight simulators and flight training devices.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Approval of flight simulators and flight... Flight Crewmember Requirements § 125.297 Approval of flight simulators and flight training devices. (a) Flight simulators and flight training devices approved by the Administrator may be used in training...

  8. Piloted Simulator Evaluation Results of New Fault-Tolerant Flight Control Algorithm

    NARCIS (Netherlands)

    Lombaerts, T.J.J.; Smaili, M.H.; Stroosma, O.; Chu, Q.P.; Mulder, J.A.; Joosten, D.A.

    2010-01-01

    A high fidelity aircraft simulation model, reconstructed using the Digital Flight Data Recorder (DFDR) of the 1992 Amsterdam Bijlmermeer aircraft accident (Flight 1862), has been used to evaluate a new Fault-Tolerant Flight Control Algorithm in an online piloted evaluation. This paper focuses on the

  9. Getting started with Twitter Flight

    CERN Document Server

    Hamshere, Tom

    2013-01-01

    Getting Started with Twitter Flight is written with the intention to educate the readers, helping them learn how to build modular powerful applications with Flight, Twitter's cutting-edge JavaScript framework.This book is for anyone with a foundation in JavaScript who wants to build web applications. Flight is quick and easy to learn, built on technologies you already understand such as the DOM, events, and jQuery.

  10. Plasma Vehicle Charging Analysis for Orion Flight Test 1

    Science.gov (United States)

    Scully, B.; Norgard, J.

    2015-01-01

    In preparation for the upcoming experimental test flight for the Orion crew module, considerable interest was raised over the possibility of exposure to elevated levels of plasma activity and vehicle charging both externally on surfaces and internally on dielectrics during the flight test orbital operations. Initial analysis using NASCAP-2K indicated very high levels of exposure, and this generated additional interest in refining/defining the plasma and spacecraft models used in the analysis. This refinement was pursued, resulting in the use of specific AE8 and AP8 models, rather than SCATHA models, as well as consideration of flight trajectory, time duration, and other parameters possibly affecting the levels of exposure and the magnitude of charge deposition. Analysis using these refined models strongly indicated that, for flight test operations, no special surface coatings were necessary for the Thermal Protection System (TPS), but would definitely be required for future GEO, trans-lunar, and extra-lunar missions.

  11. Aerial Survey of Ames Research Center - Flight Simulation Complex' Flight simulators create an

    Science.gov (United States)

    1967-01-01

    Aerial Survey of Ames Research Center - Flight Simulation Complex' Flight simulators create an authentic aircraft environment by generating the appropriate physical cues that provide the sensations of flight.

  12. Cortisol, insulin and leptin during space flight and bed rest

    Science.gov (United States)

    Stein, T. P.; Schluter, M. D.; Leskiw, M. J.

    1999-01-01

    Most ground based models for studying muscle atrophy and bone loss show reasonable fidelity to the space flight situation. However there are some differences. Investigation of the reasons for these differences can provide useful information about humans during space flight and aid in the refinement of ground based models. This report discusses three such differences, the relationships between: (i) cortisol and the protein loss, (ii) cortisol and ACTH and (iii) leptin, insulin and food intake.

  13. A unified flight control methodology for a compound rotorcraft in fundamental and aerobatic maneuvering flight

    Science.gov (United States)

    Thorsen, Adam

    regime. An energy management system was developed in order to manage performance limits (namely power required) to promote carefree maneuvering and alleviate pilot workload. This system features limits on pilot commands and has additional logic for preserving control margins and limiting maximum speed in a dive. Nonlinear dynamic inversion (NLDI) is the framework of the unified controller, which incorporates primary and redundant controls. The inner loop of the NLDI controller regulates bank angle, pitch attitude, and yaw rate, while the outer loop command structure is varied (three modes). One version uses an outer loop that commands velocities in the longitudinal and vertical axes (velocity mode), another commands longitudinal acceleration and vertical speed (acceleration mode), and the third commands longitudinal acceleration and transitions from velocity to acceleration command in the vertical axis (aerobatic mode). The flight envelope is discretized into low, cruise, and high speed flight regimes. The unified outer loop primary control effectors for the longitudinal and vertical axes (collective pitch, pitch attitude, and propeller pitch) vary depending on flight regime. A weighted pseudoinverse is used to phase either the collective or propeller pitch in/out of a redundant control role. The controllers were evaluated in Penn State's Rotorcraft Flight Simulator retaining the cyclic stick for vertical and lateral axis control along with pedal inceptors for yaw axis control. A throttle inceptor was used in place of the pilot's traditional left hand inceptor for longitudinal axis control. Ultimately, a simple rigid body model of the aircraft was sufficient enough to design a controller with favorable performance and stability characteristics. This unified flight control system promoted a low enough pilot workload so that an untrained pilot (the author) was able to pilot maneuvers of varying complexity with ease. The framework of this unified system is generalized

  14. Wing Kinematics and Wake Velocity Characteristics of Bat Flight

    Science.gov (United States)

    Swartz, Sharon

    2005-11-01

    Bats demonstrate unequalled flight characteristics and are capable of highly efficient flight as well as extreme maneuverability at high speeds. They have morphological properties that are unique in the animal world including jointed wings skeletons, elastic wing membranes and very complex wing motions. We report on a series of experiments on bats flying in a flight cage along both a straight path and through a 90-degree turn. Measurements of their kinematic wing motion (using high speed photography) and wake velocity structures (using stereo PIV) are reported. The live animal measurements are also interpreted with the help of a series of companion wind tunnel experiments using model structures that mimic some key features of bat flight mechanics. The results reveal a complex vortex wake structure which is compared and contrasted to that found in bird and insect flight.

  15. SSI-ARC Flight Test 3 Data Review

    Science.gov (United States)

    Gong, Chester; Wu, Minghong G.

    2015-01-01

    The "Unmanned Aircraft System (UAS) Integration into the National Airspace System (NAS)" Project conducted flight test program, referred to as Flight Test 3, at Armstrong Flight Research Center from June - August 2015. Four flight test days were dedicated to the NASA Ames-developed Detect and Avoid (DAA) System referred to as Autoresolver. The encounter scenarios, which involved NASA's Ikhana UAS and a manned intruder aircraft, were designed to collect data on DAA system performance in real-world conditions and uncertainties with four different surveillance sensor systems. Resulting flight test data and analysis results will be used to evaluate the DAA system performance (e.g., trajectory prediction accuracy, threat detection) and to add fidelity to simulation models used to inform Minimum Operating Performance Standards (MOPS) for integrating UAS into routine NAS operations.

  16. Cibola flight experiment satellite

    Science.gov (United States)

    Davies, P.; Liddle, Doug; Paffett, John; Sweeting, Martin; Curiel, A.; Sun, Wei; Eves, Stuart

    2004-11-01

    In order to achieve an "economy of scale" with respect to payload capacity the major trend in telecommunications satellites is for larger and larger platforms. With these large platforms the level of integration between platform and payload is increasing leading to longer delivery schedules. The typical lifecycle for procurement of these large telecommunications satellites is now 3-6 years depending on the level of non-recurring engineering needed. Surrey Satellite Technology Ltd (SSTL) has designed a low-cost platform aimed at telecommunications and navigation applications. SSTL's Geostationary Minisatellite Platform (GMP) is a new entrant addressing the lower end of the market with payloads up to 250kg requiring less than 1.5 kW power. The British National Space Centre through the MOSAIC Small Satellite Initiative supported the development of GMP. The main design goals for GMP are low-cost for the complete mission including launch and operations and a platform allowing flexible payload accommodation. GMP is specifically designed to allow rapid development and deployment with schedules typically between 1 and 2 years from contract signature to flight readiness. GMP achieves these aims by a modular design where the level of integration between the platform and payload is low. The modular design decomposes the satellite into three major components - the propulsion bay, the avionics bay and the payload module. Both the propulsion and avionics bays are reusable, largely unchanged, and independent of the payload configuration. Such a design means that SSTL or a 3rd party manufacturer can manufacture the payload in parallel to the platform with integration taking place quite late in the schedule. In July 2003 SSTL signed a contract for ESA's first Galileo navigation satellite known as GSTBV2/A. The satellite is based on GMP and ESA plan to launch it into a MEO orbit late in 2005. The second flight of GMP is likely to be in 2006 carrying a geostationary payload

  17. Stirling to Flight Initiative

    Science.gov (United States)

    Hibbard, Kenneth E.; Mason, Lee S.; Ndu, Obi; Smith, Clayton; Withrow, James P.

    2016-01-01

    Flight (S2F) initiative with the objective of developing a 100-500 We Stirling generator system. Additionally, a different approach is being devised for this initiative to avoid pitfalls of the past, and apply lessons learned from the recent ASRG experience. Two key aspects of this initiative are a Stirling System Technology Maturation Effort, and a Surrogate Mission Team (SMT) intended to provide clear mission pull and requirements context. The S2F project seeks to lead directly into a DOE flight system development of a new SRG. This paper will detail the proposed S2F initiative, and provide specifics on the key efforts designed to pave a forward path for bringing Stirling technology to flight.

  18. SHEFEX II Flight Instrumentation And Preparation Of Post Flight Analysis

    Science.gov (United States)

    Thiele, Thomas; Siebe, Frank; Gulhan, Ali

    2011-05-01

    A main disadvantage of modern TPS systems for re- entry vehicles is the expensive manufacturing and maintenance process due to the complex geometry of these blunt nose configurations. To reduce the costs and to improve the aerodynamic performance the German Aerospace Center (DLR) is following a different approach using TPS structures consisting of flat ceramic tiles. To test these new sharp edged TPS structures the SHEFEX I flight experiment was designed and successfully performed by DLR in 2005. To further improve the reliability of the sharp edged TPS design at even higher Mach numbers, a second flight experiment SHEFEX II will be performed in September 2011. In comparison to SHEFEX I the second flight experiment has a fully symmetrical shape and will reach a maximum Mach number of about 11. Furthermore the vehicle has an active steering system using four canards to control the flight attitude during re-entry, e.g. roll angle, angle of attack and sideslip. After a successful flight the evaluation of the flight data will be performed using a combination of numerical and experimental tools. The data will be used for the improvement of the present numerical analysis tools and to get a better understanding of the aerothermal behaviour of sharp TPS structures. This paper presents the flight instrumentation of the SHEFEX II TPS. In addition the concept of the post flight analysis is presented.

  19. Atmospheric radiation flight dose rates

    Science.gov (United States)

    Tobiska, W. K.

    2015-12-01

    Space weather's effects upon the near-Earth environment are due to dynamic changes in the energy transfer processes from the Sun's photons, particles, and fields. Of the domains that are affected by space weather, the coupling between the solar and galactic high-energy particles, the magnetosphere, and atmospheric regions can significantly affect humans and our technology as a result of radiation exposure. Space Environment Technologies (SET) has been conducting space weather observations of the atmospheric radiation environment at aviation altitudes that will eventually be transitioned into air traffic management operations. The Automated Radiation Measurements for Aerospace Safety (ARMAS) system and Upper-atmospheric Space and Earth Weather eXperiment (USEWX) both are providing dose rate measurements. Both activities are under the ARMAS goal of providing the "weather" of the radiation environment to improve aircraft crew and passenger safety. Over 5-dozen ARMAS and USEWX flights have successfully demonstrated the operation of a micro dosimeter on commercial aviation altitude aircraft that captures the real-time radiation environment resulting from Galactic Cosmic Rays and Solar Energetic Particles. The real-time radiation exposure is computed as an effective dose rate (body-averaged over the radiative-sensitive organs and tissues in units of microsieverts per hour); total ionizing dose is captured on the aircraft, downlinked in real-time, processed on the ground into effective dose rates, compared with NASA's Langley Research Center (LaRC) most recent Nowcast of Atmospheric Ionizing Radiation System (NAIRAS) global radiation climatology model runs, and then made available to end users via the web and smart phone apps. Flight altitudes now exceed 60,000 ft. and extend above commercial aviation altitudes into the stratosphere. In this presentation we describe recent ARMAS and USEWX results.

  20. NASA Goddard Space Flight Center presents Enhancing Standards Based Science Curriculum through NASA Content Relevancy: A Model for Sustainable Teaching-Research Integration Dr. Robert Gabrys, Raquel Marshall, Dr. Evelina Felicite-Maurice, Erin McKinley

    Science.gov (United States)

    Marshall, R. H.; Gabrys, R.

    2016-12-01

    NASA Goddard Space Flight Center has developed a systemic educator professional development model for the integration of NASA climate change resources into the K-12 classroom. The desired outcome of this model is to prepare teachers in STEM disciplines to be globally engaged and knowledgeable of current climate change research and its potential for content relevancy alignment to standard-based curriculum. The application and mapping of the model is based on the state education needs assessment, alignment to the Next Generation Science Standards (NGSS), and implementation framework developed by the consortium of district superintendents and their science supervisors. In this presentation, we will demonstrate best practices for extending the concept of inquiry-based and project-based learning through the integration of current NASA climate change research into curriculum unit lessons. This model includes a significant teacher development component focused on capacity development for teacher instruction and pedagogy aimed at aligning NASA climate change research to related NGSS student performance expectations and subsequent Crosscutting Concepts, Science and Engineering Practices, and Disciplinary Core Ideas, a need that was presented by the district steering committee as critical for ensuring sustainability and high-impact in the classroom. This model offers a collaborative and inclusive learning community that connects classroom teachers to NASA climate change researchers via an ongoing consultant/mentoring approach. As a result of the first year of implementation of this model, Maryland teachers are implementing NGSS unit lessons that guide students in open-ended research based on current NASA climate change research.