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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Návrh algoritmu redukce síly na řídící ploše letadla / Algorithm for Reduction of Force Fight on Airplane Control Surface

Szásziová, Lenka January 2011 (has links)
Digitální Fly-by-Wire systém je novým přístupem k řídícímu systému letadla, na jehož základě firma Honeywell - HTS CZ začala výzkumný projekt s názvem “Next Generation Distributed Fly-by-Wire System” a tato práce je jeho součástí. Řídící plochy letadla jsou řízeny dvěma nebo třemi elektrohydraulickými (či elektrickými) servy a každé servo je ovládáno nezávislou řídící jednotkou. Díky provozním tolerancím systému a drobným odchylkám vstupních dat v řídících jednotkách, dostává každé servo mírně odlišné povely a rozdíl v poloze serv vede k namáhání řídící plochy i k namáhání serv. Hlavním cílem této práce je navrhnout algoritmus, který bude eliminovat rozdíly mezi polohami jednotlivých serv, a tudíž sníží sílu, která namáhá řídící plochu, na přípustnou mez. Implementace řídícího systému letadla byla do detailu analyzována a algoritmus redukce síly na kontrolní ploše letadla byl navržen a implementován v prostředí Simulink. Iterační kriteriální ladící metoda byla vyvinuta a za účelem co nejlepšího nastavení algoritmu redukce síly. Práce také analyzuje vliv časových zpoždení na sběrnici na kvalitu algoritmu redukce síly.
12

Flight Test Evaluation of a Hi-Speed Near Real-Time 720I Image Processing Application

Guarino de Vasconcelos, Luiz Eduardo, Leite, Nelson Paiva Oliveira, Pinheiro, Carlos Alberto Murari, Carpinteiro, Otávio Augusto Salgado 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Nowadays, with the development of the electronics, a video camera can produce hi-resolution and hi-speed images with a very good sensitivity. A typical application is the execution of the Air Data System (ADS) Calibration Flight Test Campaign (FTC) using the Tower-Fly-By method, where the aircraft reference altitude is computed from video frames. To improve efficiency, safety and effectiveness for this FTC, the Flight Test Research Institute (IPEV) developed a near real-time video processing application to compute the aircraft altitude from 720i video frames at up to 400 fps. This development was executed as Master Science dissertation along with Itajubá State University (UNIFEI). Tests results demonstrated satisfactory performance for this tool compared to Ground Telemetry System (GTS) and Global Positioning System (GPS).
13

Flying and handling qualities of a fly-by-wire blended-wing-body civil transport aircraft

de Castro, Helena V. 12 1900 (has links)
The blended-wing-body (BWB) configuration appears as a promising contender for the next generation of large transport aircraft. The idea of blending the wing with the fuselage and eliminating the tail is not new, it has long been known that tailless aircraft can suffer from stability and control problems that must be addressed early in the design. This thesis is concerned with identifying and then evaluating the flight dynamics, stability, flight controls and handling qualities of a generic BWB large transport aircraft concept. Longitudinal and lateral-directional static and dynamic stability analysis using aerodynamic data representative of different BWB configurations enabled a better understanding of the BWB aircraft characteristics and identification of the mechanisms that influence its behaviour. The static stability studies revealed that there is limited control power both for the longitudinal and lateral-directional motion. The solution for the longitudinal problem is to limit the static margins to small values around the neutral point, and even to use negative static margins. However, for the directional control problem the solution is to investigate alternative ways of generating directional control power. Additional investigation uncovered dynamic instability due to the low and negative longitudinal and directional static stability. Furthermore, adverse roll and yaw responses were found to aileron inputs. The implementation of a pitch rate command/attitude hold flight control system (FCS) improved the longitudinal basic BWB characteristics to satisfactory levels, or Level 1, flying and handling qualities (FHQ). Although the lateral-directional command and stability FCS also improved the BWB flying and handling qualities it was demonstrated that Level 1 was not achieved for all flight conditions due to limited directional control power. The possibility to use the conventional FHQs criteria and requirements for FCS design and FHQs assessment on BWB configurations was also investigated. Hence, a limited set of simulation trials were undertaken using an augmented BWB configuration. The longitudinal Bandwidth/Phase delay/Gibson dropback criteria, as suggested by the military standards, together with the Generic Control Anticipation Parameter (GCAP) proved possible to use to assess flying and handling qualities of BWB aircraft. For the lateral-directional motion the MIL-F-8785C criteria were used. Although it is possible to assess the FHQ of BWB configuartions using these criteria, more research is recommended specifically on the lateral-directional FHQs criteria and requirements of highly augmented large transport aircraft.
14

Patched conic interplanetary trajectory design tool

Brennan, Martin James 15 February 2012 (has links)
One of the most important aspects of preliminary interplanetary mission planning entails designing a trajectory that delivers a spacecraft to the required destinations and accomplishes all the objectives. The design tool described in this thesis allows an investigator to explore various interplanetary trajectories quickly and easily. The design tool employs the patched conic method to determine heliocentric and planetocentric trajectory information. An existing Lambert Targeting routine and other common algorithms are utilized in conjunction with the design tool’s specialized code to formulate an entire trajectory from Earth departure to arrival at the destination. The tool includes many options for the investigator to accurately configure the desired trajectory, including planetary gravity assists, deep space maneuvers, and various departure and arrival conditions. The trajectory design tool is coded in MATLAB, which provides access to three dimensional plotting options and user adaptability. The design tool also incorporates powerful MATLAB optimization functions that adjust trajectory characteristics to find a configuration that yields the minimum spacecraft propellant in the form of change in velocity. / text
15

Formal specification of requirements for analytical redundancy based fault tolerant flight control systems

Del Gobbo, Diego. January 2000 (has links)
Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains ix, 185 p. : ill. Includes abstract. Includes bibliographical references (p. 87-91).
16

Improvisação na música contemporânea de concerto : parâmetros para execução da cadenza da peça "The days fly by" de Frederic Rzewski

Haro, Diogo de January 2006 (has links)
A presente pesquisa apresenta uma proposta de treinamento para a improvisação de uma cadenza na peça “The Days Fly By” de Frederick Rzewski. A improvisação é um aspecto que se manifesta de várias maneiras no trabalho e na trajetória deste compositor, sendo ele próprio pianista reconhecido por seus improvisos de cadenzas em concertos tradicionais. Seu processo de composição está intimamente relacionado ao da improvisação. É comum em suas composições a inclusão de uma seção em aberto para ser improvisada pelo intérprete. Utilizo os conceitos de referente, base de conhecimento de Jeff Pressing e ponto de partida de Bruno Nettl associados a um modelo de aprendizagem da improvisação proposto por Barry J. Kenny & Martin Gellrich. Esta pesquisa apresenta proposta de exercícios de improvisação fundamentados nos elementos detectados em uma análise da peça. / This research presents a training proposal for the improvisation of a cadenza in Frederich Rzewski!s"the Days Fly By". Improvisation is an aspect that, in several forms, appears in the work and trajectory of this composer. Himself a pianist, he is well known for his improvisations of cadenzas in traditional concerts. He has been a jazz musician and his process of composition is intimately related to the improvisation. It is usual to find in his compositions the inclusion of an open section to be improvised by the performer. I utilize Jeff Pressing!s concepts of referent, knowledge base and Bruno Netti!s point of departure associated to a training model of improvisation proposed by Barry J. Kenny and Martin Gellich. This research presents a proposal for exercises of improvisation grounded in revealed elements on an analysis of the piece.
17

Flying and handling qualities of a fly-by-wire blended-wing-body civil transport aircraft

de Castro, Helena V. January 2003 (has links)
The blended-wing-body (BWB) configuration appears as a promising contender for the next generation of large transport aircraft. The idea of blending the wing with the fuselage and eliminating the tail is not new, it has long been known that tailless aircraft can suffer from stability and control problems that must be addressed early in the design. This thesis is concerned with identifying and then evaluating the flight dynamics, stability, flight controls and handling qualities of a generic BWB large transport aircraft concept. Longitudinal and lateral-directional static and dynamic stability analysis using aerodynamic data representative of different BWB configurations enabled a better understanding of the BWB aircraft characteristics and identification of the mechanisms that influence its behaviour. The static stability studies revealed that there is limited control power both for the longitudinal and lateral-directional motion. The solution for the longitudinal problem is to limit the static margins to small values around the neutral point, and even to use negative static margins. However, for the directional control problem the solution is to investigate alternative ways of generating directional control power. Additional investigation uncovered dynamic instability due to the low and negative longitudinal and directional static stability. Furthermore, adverse roll and yaw responses were found to aileron inputs. The implementation of a pitch rate command/attitude hold flight control system (FCS) improved the longitudinal basic BWB characteristics to satisfactory levels, or Level 1, flying and handling qualities (FHQ). Although the lateral-directional command and stability FCS also improved the BWB flying and handling qualities it was demonstrated that Level 1 was not achieved for all flight conditions due to limited directional control power. The possibility to use the conventional FHQs criteria and requirements for FCS design and FHQs assessment on BWB configurations was also investigated. Hence, a limited set of simulation trials were undertaken using an augmented BWB configuration. The longitudinal Bandwidth/Phase delay/Gibson dropback criteria, as suggested by the military standards, together with the Generic Control Anticipation Parameter (GCAP) proved possible to use to assess flying and handling qualities of BWB aircraft. For the lateral-directional motion the MIL-F-8785C criteria were used. Although it is possible to assess the FHQ of BWB configuartions using these criteria, more research is recommended specifically on the lateral-directional FHQs criteria and requirements of highly augmented large transport aircraft.
18

Improvisação na música contemporânea de concerto : parâmetros para execução da cadenza da peça "The days fly by" de Frederic Rzewski

Haro, Diogo de January 2006 (has links)
A presente pesquisa apresenta uma proposta de treinamento para a improvisação de uma cadenza na peça “The Days Fly By” de Frederick Rzewski. A improvisação é um aspecto que se manifesta de várias maneiras no trabalho e na trajetória deste compositor, sendo ele próprio pianista reconhecido por seus improvisos de cadenzas em concertos tradicionais. Seu processo de composição está intimamente relacionado ao da improvisação. É comum em suas composições a inclusão de uma seção em aberto para ser improvisada pelo intérprete. Utilizo os conceitos de referente, base de conhecimento de Jeff Pressing e ponto de partida de Bruno Nettl associados a um modelo de aprendizagem da improvisação proposto por Barry J. Kenny & Martin Gellrich. Esta pesquisa apresenta proposta de exercícios de improvisação fundamentados nos elementos detectados em uma análise da peça. / This research presents a training proposal for the improvisation of a cadenza in Frederich Rzewski!s"the Days Fly By". Improvisation is an aspect that, in several forms, appears in the work and trajectory of this composer. Himself a pianist, he is well known for his improvisations of cadenzas in traditional concerts. He has been a jazz musician and his process of composition is intimately related to the improvisation. It is usual to find in his compositions the inclusion of an open section to be improvised by the performer. I utilize Jeff Pressing!s concepts of referent, knowledge base and Bruno Netti!s point of departure associated to a training model of improvisation proposed by Barry J. Kenny and Martin Gellich. This research presents a proposal for exercises of improvisation grounded in revealed elements on an analysis of the piece.
19

Improvisação na música contemporânea de concerto : parâmetros para execução da cadenza da peça "The days fly by" de Frederic Rzewski

Haro, Diogo de January 2006 (has links)
A presente pesquisa apresenta uma proposta de treinamento para a improvisação de uma cadenza na peça “The Days Fly By” de Frederick Rzewski. A improvisação é um aspecto que se manifesta de várias maneiras no trabalho e na trajetória deste compositor, sendo ele próprio pianista reconhecido por seus improvisos de cadenzas em concertos tradicionais. Seu processo de composição está intimamente relacionado ao da improvisação. É comum em suas composições a inclusão de uma seção em aberto para ser improvisada pelo intérprete. Utilizo os conceitos de referente, base de conhecimento de Jeff Pressing e ponto de partida de Bruno Nettl associados a um modelo de aprendizagem da improvisação proposto por Barry J. Kenny & Martin Gellrich. Esta pesquisa apresenta proposta de exercícios de improvisação fundamentados nos elementos detectados em uma análise da peça. / This research presents a training proposal for the improvisation of a cadenza in Frederich Rzewski!s"the Days Fly By". Improvisation is an aspect that, in several forms, appears in the work and trajectory of this composer. Himself a pianist, he is well known for his improvisations of cadenzas in traditional concerts. He has been a jazz musician and his process of composition is intimately related to the improvisation. It is usual to find in his compositions the inclusion of an open section to be improvised by the performer. I utilize Jeff Pressing!s concepts of referent, knowledge base and Bruno Netti!s point of departure associated to a training model of improvisation proposed by Barry J. Kenny and Martin Gellich. This research presents a proposal for exercises of improvisation grounded in revealed elements on an analysis of the piece.
20

Analýza datového toku ve Fly-by-Wire systému / Analysis of Data Flow in the Fly-by-Wire System

Kubínová, Zuzana January 2010 (has links)
Software implementovaný v rámci Fly-by-Wire systému firmy Honeywell je složen z mnoha modelů implementovaných v systému Simulink. Tato práce se zabývá hledáním přímých a nepřímých spojitostí mezi jednotlivými signály v systému těchto modelů. Jako vhodný aparát je zvolena teorie grafů. Na základě modelů jsou vygenerovány grafy a úloha nalézt spojitost mezi signály je převedena na úlohu nalézt cestu mezi dvěma vrcholy grafu. Známé algoritmy k vyhledávání cest v grafech určují délku nebo váhu nalezené cesty. Pro tuto aplikaci je ale potřeba rozlišovat cesty primární a sekundární bez ohledu na jejich délku. Proto jsou tyto známé algoritmy upraveny.

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