Dissertations / Theses: 'Avionics Design and construction'

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Byrne, James Michael Jr. "Resource-constrained avionics design for CubeSats." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105559.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2016.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 90-92).
We present an optimization approach to CubeSat avionics design which considers the consumption of some resources (electrical power, volume) and production of others (processing power, volatile memory, non-volatile memory, and radiation tolerance) in a quantitative optimization analysis. We present the avionics hardware design for the Microwave Radiometer Technology Acceleration (MiRaTA) 3U CubeSat, funded by the NASA Earth Science Technology Office (ESTO), as a case study for our optimization analysis. MiRaTA will demonstrate a three-band microwave radiometer and GPS radio occultation (GPSRO) sensor suite for profiling atmospheric temperature, humidity, and cloud ice. The goal is to increase the Technology Readiness Level (TRL) of the weather-sensing technology from TRL 5 to TRL 71. The avionics system is the "central nervous system" of the spacecraft, managing interfaces with every subsystem and between the Bus and Payload. MiRaTA's avionics design supports the Payload, which is tasked with the science mission to gather and process appropriate radiometer and GPSRO data, and the Bus, which comprises subsystems to handle attitude determination and control (ADC), power regulation and distribution, communications with the ground station, thermal management, and a suite of sensors and telemetry components. MiRaTA's avionics system uses a custom designed motherboard with a PIC24FJ256GB210 microcontroller to command activity in the Bus and manage data and power for the Payload. This custom Motherboard - dubbed the "Micron Motherboard" - leverages many of the advantages of the popular Pumpkin Motherboard but with reduced complexity and improved performance. The MiRaTA avionics system is also designed to minimize the number and length of cables, simplify connector uniformity, and improve accessibility. The design improvement in avionics hardware from MicroMAS to MiRaTA is quantified using an optimization coefficient: 1.522. We expect optimization coefficients to range typically from -4 to +4, so this design indicates a modest improvement.
by James Michael Byrne, Jr.
S.M.

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Ellis, Colleen Laverna, and Allan D. Kraus. "Preliminary design of a water cooled avionics rack." Thesis, Monterey, California: Naval Postgraduate School, 1993. http://hdl.handle.net/10945/24217.

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Törnblom, John. "Improving Quality of Avionics Software Using Mutation Testing." Thesis, Linköpings universitet, Databas och informationsteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-105456.

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Mutation testing is a powerful fault-based testing technique that makes syntactic changes to a program under test in order to simulate real faults otherwise caused by a programmer. Similar to structural coverage criteria such as statement coverage, mutation testing is used to assess the quality of a test suite. After a syntactic change has been made, the program is referred to as a mutant that either can survive a test suite, or be killed by one. If a mutant is killed, it means that the test suite has detected the syntactic change and reported it as an error, resulting in an increased mutation score. If a mutant survives, it means that the test suite failed to detect the fault and the mutation score is decreased. Mutation testing is generally considered the strongest testing technique available in terms of fault detection, but also the most expensive one. However, thanks to recent research and the rapid development of computing hardware, the testing technique is starting to become feasible, motivating the creation of tools utilizing the power of mutation testing. Saab AB, the Swedish aircraft manufacturer and stakeholder in this thesis, has experimented with mutation testing in the past, resulting in a tool called BAX that creates textual modifications of the original source code. The initial goal of this thesis is to provide a new tool that is faster than BAX, and that is more systematic in the way mutants are generated. LLVM-P86, the main contribution of this thesis, is a compiler and mutation testing framework intended for the programming language Pascal-86. Unlike BAX, LLVM-P86 is able to encode several mutants into a single program, thus reducing the time spent on compiling source code. In the conducted experiments, LLVM-P86 processed mutants significantly faster than BAX, on average by a factor of 13.6. Since LLVM-P86 is also a compiler, proper type information is available when mutants are generated. The additional type information allows LLVM-P86 to avoid a significant amount of equivalent mutants, i.e. mutants that behave in the same way as the original program. When mutating relational operators found in approximately 10,000 lines of code, distributed amongst 18 different Pascal-86 modules, LLVM-P86 was able to reduce the total number of living mutants by 25%, or 5.7% of the complete set of mutants.

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Kahn, Aaron David. "The design and development of a modular avionics system." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/15712.

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Vetter, David B. (David Brian). "Design of multi-passage cooling systems for avionics applications." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/115475.

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Omelchenko, Alexander 1968. "Avionics systems design for cooperative unmanned air and ground vehicles." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/17789.

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Thesis (S.M. and E.A.A.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2004.
"June 2004."
Includes bibliographical references (p. 95).
This thesis summarizes the results of the design of avionics systems intended for use onboard unmanned air and ground vehicles, that are parts of a multi-vehicle system whose primary mission objective is to provide up-close surveillance capability from a large stand-off distance. Different types of cooperative action between air and ground vehicles, that can help to enhance the overall system surveillance capability, are analyzed, including communication relay, simultaneous visual surveillance of ground objects from air and ground vehicles, and visual coverage of ground vehicles from air vehicles. Both hardware and software design as well as practical implementation of the designed avionics systems are discussed, and results of field tests are presented.
by Alexander Omelchenko.
S.M.and E.A.A.

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Carvalho, Fabiano Costa. "On the design of integrated modular avionics assisted by formal modeling." Instituto Tecnológico de Aeronáutica, 2009. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1218.

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Avionics system manufacturers are currently facing the problem of developing highly-integrated systems under economic pressures. In this scenario, the empirical approach, characterized by trial and error techniques, is not adequate since the correction of design flaws is often related to expensive re-work and schedule overruns. The evolution of airborne systems toward Integrated Modular Avionics (IMA) pushes the need for advanced methods that could enforce correctness of complex designs while minimizing the chances of introducing errors. Considering this problem, this work proposes a systematic conceptual design strategy based on formal methods, aiming at improving the development processes for IMA systems. The basic idea is to concentrate efforts on the construction, simulation, and formal analysis of a mathematical model for the new system at early development lifecycle phases. The proposed approach was exercised on a case study of practical avionics project in order to evaluate the drawbacks and advantages. Results suggest that this work could contribute to the aeronautics industry by offering alternative means to cope with complexity in modern avionics projects.

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Gia, M. C. "Design of data structures for terrain reference navigation." Thesis, Cranfield University, 1994. http://hdl.handle.net/1826/4184.

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This thesis describes the design of a data structure for use with Digitised Terrain Elevation Data (DTED) in Terrain Reference Navigation (TRN) systems. The data structure is based on a variant of quad-tree and oct-tree data structures to provide an efficient representation of terrain in terms of storage requirements and acccss operations. These data structure are applied to flight path planning operations in mission management applications. The algorithms developed for flight path planning have becri implemented in the C programming language for a standard PC. Current research in TRN systems is reviewed and attention is given to the use of hierarchical data structures to cope with the potentially large data base needed for DTED files. Data structure combining quad-trees and oct-trees are developed with an emphasis on data reduction using pointerless trees and the use of locational codes to provide straightforward mapping between quad-trees and oct-trees, in other words, between two-dimensional co-ordinates and three-dimensional co-ordinates. Analysis of these algorithms is described for two DTED files to illustrate storage improvements and to verify a set of database access operations. These data structures are applied to problems of flight path planning where the navigation space comprises objects above a specific altitude and this three-dimensional space is searched for a flight path which avoids the obstacles and satisfies specific operational criteria. Algorithms are developed to extract a visibility graph from the terrain database and to determine the preferred flight path from a set of paths which satisfy defined constraints. Several search techniques are developed which exploit the efficiency of the quad-tree and oct-tree data structures. These methods are extended to real-time flight-path planning where predicted times for access operations are used to direct flight path extraction by varying the tree resolution during computation of the flight path. A comprehensive set of results are provided to illustrate: the storage efficiency of quad-tree and oct-tree data structures the application of pyramid structures to represent navigation space analysis of the time to compute the visibility graph and to extract flight paths integration of these methods with a real-time mission management simulation on a PC The thesis draws conclusions on the efficiency of these techniques for the represcntation of DTEDs and to access objects in TRN systems. It is observed that the use of hierarchical data structures in the form of quad-trees and oct-trees offers significant improvement in accessing DTEDS, for future use in TRN systems. The thesis concludes by outlining areas of further work where the techniques can be further &N, cloped for applications in mission management and navigation using DTED files.

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Ba, Kadiata. "Intégration de la modélisation du matériau et du procédé pour le design et l'optimisation d'une composante de train d'atterrissage d'avion : procédé de forgeage." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/29950.

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Le présent travail concerne l’intégration de la modélisation du matériau et du procédé dans le design et l’optimisation d’une composante de train d’atterrissage d’avion fabriquée par forgeage à chaud en collaboration avec la société Héroux-Devtek. Pour mener à bien cette tâche, un travail d’investigation des différents aspects du matériau, du procédé et des techniques de modélisations numériques a été effectué. Une caractérisation des propriétés mécaniques et métallurgiques de l’alliage d’aluminium 7175 sous différentes conditions a été réalisée, ce qui a conduit à une meilleure connaissance du comportement de cet alliage notamment dans les conditions de forgeage. Le modèle de comportement de Johnson-Cook a été caractérisé et utilisé pour les simulations des différents cas d’analyse. Une investigation au niveau de l’intégration de l’effet de la microstructure dans le modèle de comportement a été faite. Cette étude a conduit à considérer le modèle de Johnson-Cook modifié qui a la particularité de prendre en compte les effets de la recristallisation dynamique dans le modèle d’écoulement du matériau. Une meilleure précision est obtenue en comparaison avec le modèle de Johnson-Cook standard pour des simulations impliquant de hauts niveaux de déformation. De plus, une investigation au niveau des plus récents outils de simulation a été effectuée. Une étude comparative des formulations CEL (Couplage Eulérien-Lagrangien) et SPH (Smoothed Particle Hydrodynamics) vis-à-vis de la méthode classique des ÉF (éléments finis) a permis de classifier les différentes approches selon leurs performances relatives lors des simulations du forgeage de pièces complexes en grandes transformations (écoulement de matière très important). Pour pouvoir utiliser la formulation SPH interne à Abaqus dans le cas de couplage thermomécanique, il a fallu développer un VUMAT («user ’s material») thermomécanique. Une contribution a été apportée au niveau de la méthode SPH pour la simulation plus précise du forgeage, d’abord en extensionnant un code SPH maison afin qu’il puisse résoudre des problèmes thermomécaniques couplés en grandes déformations et ensuite en transformant le code SPH en un élément de l’usager («user’s element») via l’utilitaire VUEL d’Abaqus en formulation Lagrangienne totale. En guise de validation, nous avons réalisé des travaux autant de nature numérique qu’expérimentale. Au niveau numérique, les résultats obtenus avec le code maison ont été validés par comparaison avec les résultats obtenus avec le code commercial Abaqus. Par ailleurs afin d’atteindre l’objectif principal d’intégration de la modélisation du matériau et du procédé, une méthodologie d’analyse appropriée a été développée et validée expérimentalement en concevant et en fabriquant par forgeage, un prototype représentatif de la pièce industrielle. Mots-clés : Forgeage à chaud, train d’atterrissage, caractérisation, alliages d’aluminium, Johnson-Cook, recristallisation dynamique, Abaqus, ÉF, CEL, VUMAT, VUEL SPH, formulation Lagrangienne totale, code SPH.
The present work deals with the development of an integrated material and process modeling methodology for the design and optimization of an aircraft landing gear component manufactured using hot forging process in collaboration with Héroux-Devtek. To carry out this work, an investigative work of the different aspects of the material, process and numerical modeling techniques is performed. A characterization of mechanical and metallurgical properties of the aluminum alloy 7175 under various conditions has been done and the work allowed to better know the behavior of this alloy particularly in our forging conditions. The Johnson-Cook constitutive model was characterized and used for simulations of various processes analysis. An investigation about the integration of the effect of the microstructure in the material behavior law was realized. This study led one to consider a modified Johnson-Cook model that can take account of the effects of dynamic recrystallization during the material flow. A greater accuracy was obtained in comparison with the standard Johnson- Cook model for simulations involving high strain levels. An investigation about the simulation tools was also performed. A comparative study of CEL (Coupling Eulerian-Lagrangian) and SPH (Smoothed Particle Hydrodynamics) formulation with the finite elements method (FEM) allowed to classify the different methods according to their performance in the simulations of complex forged part involving large deformations (very important material flow). To use the SPH formulation existing in Abaqus for the simulation of coupled thermomechanical problems, it was first necessary to develop a thermomechanical VUMAT (user’s material) subroutine. For more accurate simulation of forging process, a contribution was made regarding the SPH method. To do this, an independent in-house SPH code and an ABAQUS VUEL (user’s element) subroutine based on the total Lagrangian formulation of solid mechanic’s equations were developed. For validation purposes, both numerical investigations and experimental works were accomplished. Regarding the numerical simulation, the results obtained with the in-house code were validated by comparing them with results obtained using the Abaqus FE commercial code. Moreover, in order to achieve the main objective of integrated material and process modeling for the product design, a suitable methodology was developed and validated experimentally by designing and manufacturing by the closed die hot forging process, a representative prototype of the industrial part. Keywords: Hot forging, landing gear, aluminum alloys, Johnson-Cook, dynamic recrystallization, Abaqus, FE, CEL, VUMAT, VUEL SPH, total Lagrangian formulation, SPH code.

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Carrillo, Cassandra M. "Continuous biometric authentication for authorized aircraft personnel : a proposed design." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Jun%5FCarrillo.pdf.

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Gonzalez, Gallego Oscar. "Dimensionnement et contrôlabilité de configurations avion innovantes." Toulouse 3, 2013. http://www.theses.fr/2013TOU30340.

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Le processus actuel de conception avion est centré sur l'optimisation des performances du véhicule (minimiser la traînée de l'avion, réduire les niveaux de bruit, maximiser le Rayon d'Action, réduire les émissions polluantes, etc. ) et traite toutes les autres disciplines séquentiellement et en tant que contraintes de design. Parmi ces contraintes, la discipline de Stabilité & Contrôle est certainement la plus importante, bien qu'elle ne soit pas considérée comme telle. Outre le dimensionnement des stabilisateurs et des organes de contrôle de l'appareil, la Stabilité & Contrôle est intimement liée aux Performances, à la sécurité et aux aspects de certification de l'avion. Dans la première étape du cycle de conception avion (phase de Design Conceptuel), la Stabilité & Contrôle n'est traitée que partiellement et consiste simplement à exploiter des relations statistiques (coefficients de volume) et à mener quelques analyses statiques (Diagramme en Ciseaux). Ce n'est que plus tard dans le processus de développement avion (phase de Design Détaillée et essais en vol) que cette discipline joue un rôle dominant et que les choix de design faits à l'étape conceptuelle sont validés ou non. Bien que cette méthodologie de conception des stabilisateurs et des gouvernes fonctionne convenablement quand on considère des avions ayant une forme typique (voilure + fuselage tubulaire + empennage arrière), elle échoue lorsque l'on examine des avions ayant une forme non conventionnelle. De plus, la façon "simple" d'appréhender la discipline de Stabilité & Contrôle en phase conceptuelle conduit à des aéronefs sous-optimaux ayant souvent des problèmes de stabilité et/ou de contrôle qui non seulement sont coûteux à rectifier, mais qui peuvent également dégrader les performances du véhicule et compromettre sa sécurité. Ce travail de recherche a pour objectif d'établir une méthodologie de Design Conceptuel, à la fois générique, alternative et rapide, capable de dimensionner et d'optimiser tout type de configuration avion en accordant une importance particulière à la discipline de Stabilité & Contrôle. Dans cette méthodologie, le caractère séquentiel du processus de design conceptuel actuel est remplacé par une approche simultanée et intégrée d'Optimisation Multidisciplinaire (MDO), dans laquelle la discipline de Stabilité & Contrôle, en particulier, est considérée au même niveau que les Performances. L'approche de design proposée dans cette thèse vise à déterminer la forme avion satisfaisant, entre autres, un ensemble générique (i. E. Indépendant de la configuration avion) d'exigences de stabilité et de contrôle, tout en possédant les meilleures performances opérationnelles tout au long d'un profil de mission type. Comparé au processus de design avion traditionnel, le problème d'optimisation qui en résulte est davantage contraint d'un point de vue de la Stabilité & Contrôle et considère non seulement des critères statiques mais également des exigences dynamiques et de manœuvre. Cette méthodologie s'apparente à une démarche "inverse" puisque les caractéristiques souhaitées de stabilité et de contrôle sont imposées par avance en tant que contraintes du problème d'optimisation. Le concepteur cherche ainsi à déterminer la forme avion ayant des qualités de vol prédéfinies. L'intégration de la discipline de Stabilité & Contrôle dans l'étape conceptuelle de design requiert la mise à disposition d'un outil intégré et modulaire, servant de plateforme pour mener des analyses MDO. Un tel outil n'est cependant pas disponible à l'heure actuelle dans l'industrie civile. Pour pallier à ce problème, un outil simple permettant d'émuler l'environnement requis a été développé. La méthodologie présentée est illustrée avec deux configurations avion radicalement différentes mais ayant une taille semblable. Bien que le travail exposé ci-dessous ne constitue qu'une première étape pour résoudre le problème complet, on démontre cependant que la méthode est viable et que l'on peut obtenir des gains supplémentaires en performances en prenant en compte la Stabilité & Contrôle dès le stade de Design Conceptuel. L'approche permet également de comparer des configurations avions entre elles sur des bases entièrement physiques et objectives et non pas sur des opinions variées et subjectives, comme c'est le cas actuellement
The current aircraft design process focuses on Performance optimization (minimize the airframe drag, reduce noise levels, maximize Range, reduce pollutant emissions, etc. ) and treats all other disciplines sequentially and as design constraints. Among the constraint disciplines, Stability & Control is the most important one, although not always recognized as such. Indeed, in addition to being responsible for equipping the airframe with stabilizers and controls that ensure the proper handling of the vehicle, Stability & Control is strongly tied to Performance, safety, and aircraft certification aspects. In the earliest aircraft design stage (Conceptual Design phase), the Stability & Control discipline is only partially considered and consists of little more than statistical relationships (volume coefficients) and static analyses (Scissors Plot). It is not until later in the aircraft development process (Detailed Design phase and flight tests), that the Stability & Control discipline plays a dominant role and where the airplane design choices made at the conceptual level are validated or not. Although this traditional design procedure proved to be "successful" when sizing the stabilizers and controls of typical airplanes (wing + tubular fuselage + rear empennage), it fails when the aircraft layout under study deviates from the conventional one. Furthermore, the wide discrepancy between the rather sophisticated manner in which the Stability & Control discipline is considered in the Detailed Design phase, compared to the relatively simple approach used during the Conceptual Design level, results in "sub-optimal" airplane designs with stability and/or deficiencies that not only are expensive to fix, but can also be detrimental to the vehicle performance characteristics and jeopardize its safety. This research work introduces a generic, alternative, and fast aircraft conceptual design methodology capable of sizing and optimizing any aircraft configuration by giving further importance to the Stability & Control discipline. In this methodology, the sequential character of the current conceptual design process is replaced with a simultaneous and integrated Multi-Disciplinary Optimization (MDO) approach in which the discipline of Stability & Control, in particular, is considered at the same level as Performance. The proposed design procedure aims at deriving the airplane outer shape satisfying, among others, a set of generic (i. E. Independent of the aircraft configuration) stability and control requirements, while possessing the best operational performance throughout a typical mission profile. Compared to the traditional aircraft design methodology, the derived optimization problem is much more constrained from the Stability & Control perspective and considers not only static requirements, but also dynamic and maneuver criteria. The methodology resembles an "inverse" (or "reverse engineering") design process since the desired stability and control features of the airplane are imposed in advance as constraints of the optimization problem. The conceptual designer therefore seeks to determine the aircraft shape having specific handling characteristics. Integrating the Stability & Control discipline at conceptual level requires a modular and integrated tool, capable of performing MDO, that is not yet available within the civilian aviation industry. To counter this, a "simple" tool was created for partially mimicking the environment required. The methodology is illustrated with two different aircraft configurations of similar size. Although the work presented herein represents only a small fraction of the whole research challenge, the methodology is demonstrated to be viable and it is shown that further performance benefits can be extracted if the stability and control constraints are taken into account from the early design stages. This approach also enables to compare different aircraft configurations from a physical and rational basis and not on subjective and disparate opinions, as is currently the case

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Sprague, Kara Lynn 1980. "Design and validation of an avionics system for a miniature acrobatic helicopter." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87835.

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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.
Includes bibliographical references (leaves 53-54).
by Kara Lynn Sprague.
M.Eng.

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Teng, Choon Hon Adrian. "Design and performance evaluation study of a prototype of a tactical unmanned aerial vehicle." Thesis, Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Dec%5FTeng.pdf.

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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2007.
Thesis Advisor(s): Jones, Kevin D. ; Dobrokhodov, Vladimir N. "December 2007." Description based on title screen as viewed on January 18, 2008. Includes bibliographical references (p. 97-98). Also available in print.

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Andersson, Henric. "Aircraft Systems Modeling : Model Based Systems Engineering in Avionics Design and Aircraft Simulation." Licentiate thesis, Linköping University, Linköping University, Machine Design, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-17573.

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Aircraft developers like other development and manufacturing companies, are experiencing increasing complexity in their products and growing competition in the global market. One way to confront the challenges is to make the development process more efficient and to shorten time to market for new products/variants by using design and development methods based on models. Model Based Systems Engineering (MBSE) is introduced to, in a structured way, support engineers with aids and rules in order to engineer systems in a new way.

In this thesis, model based strategies for aircraft and avionics development are studied. A background to avionics architectures and in particular Integrated Modular Avionics is described. The integrating discipline Systems Engineering, MBSE and applicable standards are also described. A survey on available and emerging modeling techniques and tools, such as Hosted Simulation, is presented and Modeling Domains are defined in order to analyze the engineering environment with all its vital parts to support an MBSE approach.

Time and money may be saved by using modeling techniques that enable understanding of the engineering problem, state-of-the-art analysis and team communication, with preserved or increased quality and sense of control. Dynamic simulation is an activity increasingly used in aerospace, for several reasons; to prove the product concept, to validate stated requirements, and to verify the final implementation. Simulation is also used for end-user training, with specialized training simulators, but with the same underlying models. As models grow in complexity, and the set of simulation platforms is expanded, new needs for specification, model building and configuration support arise, which requires a modeling framework to be efficient.

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Goodwin, Thomas David. "An implementation study of an accounting system design for the Naval Avionics Center." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/28275.

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Glas, Dylan F. (Dylan Fairchild) 1975. "Vehicle concept exploration and avionics architecture design for a fast package delivery system." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9253.

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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2000.
Also available online at the MIT Theses Online homepage .
Includes bibliographical references (leaves 96-97).
Fast Package Delivery was explored as a possible commercial application of advanced reusable launch vehicle technologies. The market was divided into two distinct segments: an on-demand charter service for urgent deliveries, and a scheduled service similar to today's overnight delivery services. System reliability is a strong driver for both cases. For the on-demand case, vehicle speed is of critical importance. In order to provide on-demand service, only one customer may be served per vehicle flight. Since the price a customer will pay is highly sensitive to vehicle speed, the optimal vehicle concept was determined to be a Mach 6 hypersonic aircraft. Due to the small payload weight (200 lb) the overall vehicle size and cost are highly sensitive to equipment weight. Therefore substantial savings could be realized if the aircraft were unmanned. Flight operations would most likely be autonomous during cruise, but remotely piloted during launch and landing. Scheduled service, due to its much larger projected payload (6000 lb), is less sensitive to the weight of onboard equipment, and would not need to be unmanned. Packages from many customers would be carried at once, enabling lower prices to be charged to each customer. Lower prices mean that lower vehicle speeds would be acceptable to the customers, and so the optimal vehicle concept for scheduled service was found to be a Mach 2-3 supersonic transport. Unfortunately, due to the inherent unreliability of experimental technologies, Fast Package Delivery does not appear to be a feasible application at this time. However, once supersonic and reusable launch vehicle technologies begin to mature, Fast Package Delivery should be considered as a realistic business prospect. This paper presents the market analysis, system requirements development, vehicle concept selection, and avionics considerations for a Fast Package Delivery system.
by Dylan F. Glas.
M.Eng.

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Perez, Alberto, John Hildin, and John Roach. "Design and Implementation of an Avionics Full Duplex Ethernet (A664) Data Acquisition System." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606199.

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ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California
ARINC 664 presents the designers of data acquisition systems challenges not previously seen on other aircraft avionic buses. Among the biggest challenges are providing the test instrumentation system with the capacity to process two redundant Ethernet segments that may be carrying packet traffic at near wire-line speed. To achieve this level of performance, the hardware and software must not only perform mundane operations, like time stamping and simple virtual link MAC filtering, but also need to implement core ARINC 664 functions like redundancy management and integrity checking. Furthermore, other TCP/IP operations, such as IP header checksum, must also be offloaded to the hardware in order to maintain real-time operation. This paper describes the implementation path followed by TTC during its development of an ARINC 664 network monitor used in a large commercial aircraft flight test program.

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Tondreault, Jeremy P. (Jeremy Peter) 1973. "Improving the management of system development to produce more affordable military avionics systems." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/82698.

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Thesis (S.M.)--Massachusetts Institute of Technology, System Design & Management Program, 2003.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
"February 2003."
Includes bibliographical references (p. 126-127).
by Jeremy P. Tondreault.
S.M.

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Silva, Leon M. (Leon Manuel) 1968. "A partitioning methodology for helicopter avionics system with a focus on life cycle cost." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/82690.

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Thesis (S.M.)--Massachusetts Institute of Technology, System Design & Management Program, 2001.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 111).
by Leon M. Silva.
S.M.

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Vandeveld, Thierry F. R. "Etude expérimentale multisensorielle de la dynamique des impacts d'oiseaux sur structures d'avions." Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210274.

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Chaque année, d'innombrables collisions se produisent entre des avions en vol et des oiseaux. L'impact aviaire, menace redoutée par les pilotes, concerne tant l'aviation civile que son pendant militaire. Les statistiques démontrent que, même si fort heureusement le nombre d'accidents graves reste limité, les incidents sont de plus en plus nombreux.

Parmi les acteurs qui luttent contre ce danger, les constructeurs d'avions jouent un rôle prépondérant. Contraints par des réglementations internationales, ils s'attachent à produire des éléments de structure qui résistent à l'impact d'oiseaux.

Dans la mise au point de leur produits, les avionneurs démontrent cette résistance à l'aide d'essais d'impact :on accélère un simulant d'oiseau jusqu'à la vitesse voulue -- de l'ordre de la vitesse de croisière nominale de l'avion -- et on le projette sur un aileron ou un morceau de fuselage.

La présente thèse doctorale, co-dirigée par les professeurs Philippe Bouillard de l'ULB et Marc Pirlot de l'ERM, contribue doublement à l'amélioration de ces techniques d'essais dynamiques.

D'une part, elle réalise la mise au point et la validation d'un lanceur pyrotechnique à double étage pour l'accélération du simulant d'oiseau. Un canon de calibre 20 mm est combiné avec un accélérateur de calibre 160 mm. La combustion d'un mélange de poudre propulsive contenu dans une douille adaptée génère les gaz à haute température et à haute pression nécessaires à l'accélération d'un simulant d'oiseau dûment confiné dans un conteneur de protection. Un dispositif de séparation arrête le conteneur afin que seul le simulant d'oiseau percute l'élément d'avion à l'essai. La solution pyrotechnique à double étage mise au point est validée par de nombreux tirs instrumentés en vitesse, en accélération et en pression ;elle se révèle conforme aux exigences de sécurité et de reproductibilité. Le lanceur pyrotechnique présente par rapport aux solutions pneumatiques, utilisées à notre connaissance dans tous les autres centres d'essais, des avantages indéniables de compacité ainsi que de rapidité et de souplesse de mise en oeuvre.

D'autre part, la migration des alliages métalliques vers les matériaux composites est amorcée depuis plusieurs années déjà dans le monde de la construction aéronautique. Pour optimiser les structures, une connaissance des caractéristiques de ces matériaux est indispensable. Les modes de rupture font partie des caractéristiques encore mal connues. La mesure du déplacement hors-plan lors du tir sur panneaux plans est une des manières de quantifier le comportement du matériau sous l'action d'un impact. Cette mesure s'opère généralement de manière statique, après le tir. Une méthode de mesure dynamique a été mise au point, basée sur l'emploi de techniques de stéréoscopie par corrélation numérique d'images. Cette technique a été validée au moyen d'une méthode métrologique indépendante d'extensométrie laser.

ABSTRACT

Countless collisions occur each year between airplanes and birds. Bird strike is a concern to both civilian and militay aircraft. Statistics show that, although the number of serious accidents fortunately remains low, the number of incidents keeps increasing.

Amongst the actors tackling this issue, aircraft manufacturers play an important role. In compliance with international regulations, they have to produce structural elements that withstand bird impact. During the development of their products, aircraft manufacturers have to demonstrate this resistance through bird impact trials :a bird surrogate is accelerated to the required velocity - often close to the nominal cruise speed of the aircraft - and launched onto a flap or a piece of fuselage.

This PhD thesis has been co-supervised by Professor Philippe Bouillard (ULB) and Professor Marc Pirlot (ERM-KMS). Its contribution to the improvement of the aforementioned dynamic trials is twofold.

One one hand, a two-stage pyrotechnical launcher for bird surrogates has been developed and assessed. A 20 mm caliber gun is connected to a 160 mm diameter launcher. The combustion of a propellant mixture in a cartridge case generates high pressure, high temperature gases which accelerate a bird surrogate protected by a cylindrical container. A stripper refrains the container from hitting the target pane.

The pyrotechnical solution has been assessed through an important number of firings where pressure, velocity and acceleration have been measured. The solution has proven compliance with both the safety requirements and the repeatability specifications. Its advantages compared to the pneumatic solutions used, as far as we know, in all other test centres, include compactedness as well as flexibility and high firing rate.

On the other hand, migration towards composite materials has been initiated years ago in the area of aeronautical constructions.

To optimize structures, a thorough knowledge of these new materials is required. Failure modes belong to the still badly known features of carbon reinforced plastics. Measuring the out-of-plane deformation when firing on a flat pane is one way of quantifying the material's behaviour under impact. This measurement is most frequently made in a static way, after completion of the firing. A dynamic measuring method has been developed, based upon stereoscopic digital image correlation techniques. This technique has been validated by means of an independent laser extensometer measuring method.

Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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21

Dittrich, Joerg S. "Design and integration of an unmanned aerial vehicle navigation system." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/15669.

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Westerhoff, Kevin M. (Kevin Matthew) 1978. "Construction based design." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/84827.

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Fortunet, Charles. "Une méthode d'optimisation multicritère pour le Design For Manufacturing : application aux portes d'avion." Thesis, Université Clermont Auvergne‎ (2017-2020), 2017. http://www.theses.fr/2017CLFAC048.

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Actuellement, le marché aéronautique est en constante augmentation. Pour faire face à cela, les avionneurs doivent se restructurer et revoir les processus de fabrication des pièces. En effet, il est nécessaire d’augmenter les cadences et réduire les prix tout en conservant les performances des pièces (poids et résistance mécanique). Cependant, ces trois objectifs sont contradictoires et un compromis est difficile à trouver. Ces travaux de thèse abordent cette problématique dans le cadre du CORAC. Ils proposent une manière originale d’optimiser une pièce de structure aéronautique qui vise à développer une nouvelle approche de la conception de pièces et de processus de fabrication pour tendre vers des solutions de compromis performantes. Pour ce faire, une méthodologie multicritère en trois étapes est proposée. D’abord, l’expertise industrielle est formalisée afin de formuler le problème mathématiquement. Ensuite, un algorithme génétique est utilisé afin de déterminer une population de solutions dont les performances sont placées sur un front de Pareto.Enfin, une étape de choix parmi la population finale prenant en compte le contexte industriel est mise en place. Cette méthodologie est appliquée à une porte d’avion moyen-courrier fabriquée par matriçage puis usinage. Dans ce cas, elle permet de choisir la solution la plus adaptée au contexte industriel parmi mille solutions de compromis
Nowadays, the aeronautical market grows constantly. To face this, aircraft industry has to restructure and the manufacturing processes must be revised. Indeed, production rate must increase and manufacturing cost decrease while keeping the performances of the parts (weight and mechanical resistance). These objectives are contradictory and compromises must be found. This thesis broaches this problematic in relation to the CORAC. A novel method to optimize an aeronautical structural part and its manufacturing process is developed to tend toward performing compromise solutions. To do so, a three steps multi-criteria method is proposed. First, the industrial expertise is formalized to mathematically express the problem. Then, a genetic algorithm is used to determine a population in which every solution is located on a single Pareto front. At least, a decision step is set up to find the best solution in the population considering the industrial environment of the part. This methodology is applied to an aircraft door manufactured by forging and machining. In this case, it allows choosing the solution that fit the most the industrial environment within a one thousand solutions’ population

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Fetter, Bryan J. "Design recovery and implementation of the AYK-14 VHSIC processor module adapter with field programmable gate array technology." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FFetter.pdf.

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Thesis (M.S. in Aeronautical Engineering)--Naval Postgraduate School, December 2002.
Thesis advisor(s): Russell W. Duren, Hersch Loomis. Includes bibliographical references (p. 199). Also available online.

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Reilly, Dennis J. "Unitary Joint Standoff Captive Air Training Missile avionics design through operational concepts and functional requirements analysis /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA309753.

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Reilly, Dennis J. III. "Unitary Joint Standoff Captive Air Training Missile avionics design through operational concepts and functional requirements analysis." Thesis, Monterey, California. Naval Postgraduate School, 1996. http://hdl.handle.net/10945/9103.

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Approved for public release; distribution is unlimited.
To accurately simulate the Unitary Joint Standoff (JSOW) weapon functions and provide pilots with the most realistic training, the captive air training missile (CATM) avionics design will fully implement well defined operational concepts and functional requirements in terms of flight simulation characteristics, operational functions, pilot feedback, and electronic interfaces. This would provide the Navy, Marines, and Air Force with a single, multi-capable, light weight CATM that consolidates CATM procurement, decreases aircraft turnaround time and increases aircrew training per flight hour.

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Urbain, Francois 1974. "Vehicle design, flight control avionics, and flight tests for the Parent and Child Unmanned Air Vehicle." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/44900.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2001.
Includes bibliographical references (p. 115).
The Parent and Child Unmanned Aerial Vehicle (PCUAV) is the second project to originate from the MIT / Draper Technology Development Partnership, which aims to develop first-of-a-kind systems. The PCUAV proposes a low-cost solution to long distance closeup observation, using the cooperative action of a fleet of small UAVs. The project team will prove the potential of the system by demonstrating key enablers such as autonomous air rendezvous. This thesis presents the design of the project's vehicles, namely the Mini and Parent vehicles, and the Avionics Testbed Airplane. The avionics architecture is discussed including a detailed description of its components and their selection. The approach to obtain reliable estimates of aircraft attitude using low-cost gyroscopes is introduced. The planning and execution of several flight tests is presented.
by Francois Urbain.
S.M.

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Berrian, Joshua. "AN AUTOMATED TEST STATION DESIGN USED TO VERIFY AIRCRAFT COMMUNICATION PROTOCOLS." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/635.

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Requirements verification is typically the costliest part of the systems engineering design process. In the commercial aircraft industry, as the software and hardware design evolves, it must be verified to conform to requirements. In addition, when new design releases are made, regression analysis must be performed which usually requires repeat testing. To streamline verification, a suite of automated verification tools is described in this document which can reduce the test effort. This test suite can be qualified to be used to verify systems at any DO-178B design assurance level. Some of the software tools are briefly described below. There are major advantages of this automated verification effort. The tools can either be internally developed by a company or purchased "off the shelf", depending upon budget and staff constraints. Every automated test case can be run with the click of a button and failures caused by human factors are reduced. The station can be qualified per DO-178B guidelines, and can also be expanded to support ARINC 429, AFDX, Ethernet, and MIL-STD-1553 interfaces. The expansion of these test programs would enable the creation of a universal avionics test suite with minimal cost and a reduction of the overall program verification effort. The following is a presentation of an automated test station capable of reducing verification time and cost. The hardware and software aspects needed to create the test station are examined. Also, steps are provided to help guide a designer through the tool qualification process. Lastly, a full suite of test functions are included that can be implemented and customized to verify a wide range of avionics communication characteristics.

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Xie, Xiaoling. "Communications in construction design." Thesis, Loughborough University, 2002. https://dspace.lboro.ac.uk/2134/7571.

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Construction design has become an increasingly complex synthesis activity for which effective solutions depend upon co-operative participation by a number of people. Thus communication, including the integration of specialised knowledge and negotiation of differences between team members, is a vital process for collaborative design. A questionnaire survey was initially conducted to investigate communication issues and problems, which had been highlighted from a review of the literature, in current construction design. The results confirmed that communication among the different construction team members is often difficult although of paramount important to design outcomes. Based on these results, case studies have been carried out to gain further insights into communication issues and problems, and explore why and how they are caused. Through the application of multiple approaches, a model has been developed, which suggests strategies that may help participants communicate more effectively and ultimately improve the quality of construction design outcomes.

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Soto, Leticia S. M. Massachusetts Institute of Technology. "Construction design as a process for flow : applying lean principles to construction design." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42995.

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Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2007.
Includes bibliographical references (p. 108-111).
Delays and cost overruns are the rule rather than the exception in the construction industry. Design changes due to lack of constructability late in the construction phase generating costly ripple effect which create delay and disruption throughout the entire organization, are the largest contributors to the stated rule. In the building construction industry, of increased competitiveness, demand from many companies continued effort to develop new methods and tools, in which the design for quality, cost, construability and reliability play an important role. The planning and management of building design has historically focused upon traditional methods of planning such as Critical Path Method (CPM). Little effort is made to understand the complexities of the design process; instead design managers focus on allocating work packages where the planned output is a set of deliverables. This current design method forces design teams to manage their work on a discipline basis, each working on achieving their deliverable as dictated by the design program with little regard of the relationship with other disciplines and organizations. In addition, because Architect and Engineering firms view design and construction as two separate independent phases of work in project it makes it difficult to verify constructability in a design and create flow in the overall process. The goal of this study is to look at how aligning interests, objectives and practices based on lean fundamentals, during the earliest stages of a project, as a method of improving construction performance.
by Leticia Soto.
S.M.

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Zeaiter, Amal. "Thermal Modeling and Cooling of Electric Motors : Application to the Propulsion of Hybrid Aircraft Thermal Sensitivity Analysis of a High Power Density Electric Motor for Aeronautical Application Numerical Approach to Determining Windings’ Thermal Conductivity Electro-thermal Models and Design Approach for High Specific Power Electric Motor for Hybrid Aircraft Determination of electric motor losses and critical temperatures through an inverse approach." Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2020. http://www.theses.fr/2020ESMA0015.

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Le travail présenté dans ce mémoire concerne la modélisation thermique de moteurs électriques de forte densité de puissance. Le but est de trouver les techniques de refroidissement efficaces et adaptées aux moteurs conçus pour application à la propulsion de l’avion hybride du futur. Deux cibles de densité de puissance, 5 kW/kg pour le court terme (année 2025) et 10 kW/kg pour le long terme (année 2035), sont abordées avec leurs propres exigences. Les moteurs électriques étudiés sont de type synchrone à aimants permanents montés en surface du rotor. Ce type de moteur est caractérisé par un rendement élevé et contraint par les températures maximales admissibles relativement faibles de son bobinage et de ses aimants. Une fois atteintes, ces valeurs de température entraînent le dysfonctionnement du moteur ou la limitation de sa durée de vie. En outre, avec un design fermé imposé et des densités élevées de flux de chaleur dissipées dans la machine, une optimisation du refroidissement est incontournable.Pour se familiariser avec le problème, un état de l’art détaillé sur le refroidissement des machines électriques est réalisé. En conséquence, les différentes techniques utilisées et les avancements technologiques récents sont analysés vis-à-vis de notre cas d’application. Ensuite, afin de prédire le comportement thermique du moteur et d’assurer le suivi des températures critiques (surtout au bobinage et aux aimants), un modèle nodal transitoire est mis en place et résolu sous Matlab. Ce dernier est construit en considérant l’intégralité du système moteur avec son circuit de refroidissement. Les conditions externes liées à l’environnement sont prises en compte, en particulier la variation de la température d’air extérieur en fonction de l’altitude et le profil de mission de vol de l’avion. En effet, les pertes dans le moteur, qui constituent les sources de chaleur, varient en fonction de la puissance pendant le vol. Afin d’identifier précisément les paramètres intrinsèques du modèle, une étude par éléments finis a été menée et des corrélations permettant l’estimation de la conductivité thermique du bobinage en sont déduites par interpolation polynomiale. Plusieurs études ont ensuite été menées concernant l’influence des propriétés thermophysiques, de la température extérieure, de la nature du liquide de refroidissement, de son débit ainsi que la surface extérieure de l’échangeur sur les réponses en température du modèle. Plusieurs designs du moteur sont étudiés grâce à ce modèle afin de proposer des solutions de refroidissement adaptées. Pour chacune des cibles, une configuration optimale du moteur avec son système de refroidissement a été adoptée.Par ailleurs, les pertes électromagnétiques et mécaniques étant difficiles à estimer dans ces machines, un chapitre est consacré à leur identification par résolution d’un problème inverse. La technique est séquentielle et utilise la spécification de fonction de Beck comme méthode de régularisation. Trois cas, de complexité croissante, sont étudiés et montrent la fiabilité de la méthode qui permet également d’estimer les températures inaccessibles dans le moteur. C’est finalement ce modèle nodal à faible nombre de degré de liberté qui nous permet d’assurer, en temps réel, le suivi des points chauds
The concern of this thesis is the thermal modeling of high-specific power electric motors. The aim is to allow finding the efficient and adequate cooling solutions of the motors designed for hybrid aircraft propulsion application. Two specific power values, 5 kW/kg for the short-term (year 2025) and 10 kW/kg for the long-term (year 2035), are targeted, each with specific requirements. The investigated type of electric motors is the synchronous machine with surface-mounted permanent magnets. This motor type is constrained by relatively low values of maximum allowed temperatures in windings and magnets. Once reached, these temperature values lead to a failure in motor operation or at least to shortening its lifetime. Moreover, with a closed motor design and high heat fluxes generated, the optimization of the cooling is essential.To become acquainted with the issue, a detailed state of the art on electric machine cooling is elaborated. Then, the commonly used techniques and the recent technological advancements are analyzed with respect to our case study. Afterward, in order to predict motor thermal behavior and ensure the monitoring of critical temperatures (windings and magnets), a nodal transient model is implemented and solved on Matlab software. This latter is built for the whole system of the motor and cooling circuit. Specific conditions of the flight are taken into account, particularly the outside air temperature variation in terms of altitude and the flight mission profile. Actually, the motor losses, generating the heat in the machine, vary depending on the motor power during the mission. For the identification of crucial parameters, a Finite-Element study was conducted and corresponding correlations were elaborated to estimate the windings thermal conductivity through polynomial interpolation.Several studies were carried out involving the influence of the thermo-physical properties, the outside temperature, the coolant nature, its flow rate as well as the exchanger surface, on the temperature response of the model. This model has allowed studying several motor designs and proposing adequate cooling solutions. For each target, a final optimal configuration of the motor with its cooling system was adopted.Besides, since the electromagnetic and mechanical losses are hardly estimated in this machine type, a chapter was dedicated to identifying them through an inverse approach. A sequential technique, that uses Beck’s function specification for regularization, was developed. Three cases of unknown losses, with increasing complexity, were studied, proving the method's reliability. Finally, using the same developed low-order model, the real-time procedure also allows monitoring low-accessibility motor temperatures (specifically hot spots)

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Cranley, Nikki. "The Implications for DAU Design in a Networked Data Acquisition System." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595776.

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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
The higher bandwidth capacities available with the adoption of Ethernet technology for networked FTI data acquisition systems enable more data to be acquired by the Data Acquisition Unit (DAU) from high-speed data busses, with higher channel densities, faster sampling rates, and sample resolution. Ethernet offers increased flexibility, interoperability, and simplicity in terms of the FTI system topology. However, the adoption of Ethernet has numerous implications for the design and operation of the DAU in terms of supporting network protocols for synchronization, configuration, and the transmission of the acquired data. This paper explores these issues and discusses the merits of adopting Ethernet.

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33

Van, Wyk Robin. "Development of an integrated avionics hardware system for unmanned aerial vehicle research purposes." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6485.

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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: The development of an integrated avionics system containing all the required sensors and actuators for autopilot control is presented. The thesis analyzes the requirements for the system and presents detailed hardware design. The architecture of the system is based on an FPGA which is tasked with interfacing with the sensors and actuators. The FPGA abstracts a microprocessor from these interface modules, allowing it to focus only on the control and user interface algorithms. Firmware design for the FPGA, as well as a conceptualization of the microprocessor software design is presented. Simulation results showing the functionality of firmware modules are presented.
AFRIKAANSE OPSOMMING: Die ontwikkeling van ‘n geïntegreede avionika‐stelsel wat al die vereiste sensors en aktueerders vir outoloods‐beheer bevat, word voorgestel. Die tesis analiseer die vereistes van die stelsel en stel ‘n hardeware‐ontwerp voor. Die argitektuur van die stelsel bevat ‘n FPGA wat ‘n koppelvlak met sensors en aktueerders skep. Die FPGA verwyder die mikroverwerker weg van hierdie koppelvlak modules en stel dit sodoende in staat om slegs op die beheer en gebruikerskoppelvlak‐algoritmes te fokus. Sagteware‐ontwerp vir die FPGA, asook die konseptualisering van die sagtewareontwerp vir die mikroverwerker, word aangebied. Simulasie resultate wat die funksionaliteit van die FPGA‐sagteware modules aandui, word ook voorgestel.

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Sebille, Michel. "Design :construction, automorphisms and colourings." Doctoral thesis, Universite Libre de Bruxelles, 2002. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211428.

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Chew, En Phin. "Superconducting Transformer Design and Construction." Thesis, University of Canterbury. Electrical and Computer Engineering, 2010. http://hdl.handle.net/10092/4977.

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This thesis first outlines the testing undertaken on a partial core superconducting transformer under open circuit, short circuit, full load and endurance test conditions. During the endurance test, a failure occurred after 1 minute and 35 seconds. During the failure, voltage dipping and rapid liquid nitrogen boil off was observed. This prompted a failure investigation which concluded that the lack of cooling in the windings was the most probable cause to the failure. Full core transformer and superconductor theories are then introduced. A copper winding transformer model, based on a Steinmetz equivalent circuit and a reverse design method, is described. A superconductor loss model which outlines the different types of losses experienced under AC conditions is used to determine the resistance of the windings in the Steinmetz equivalent circuit. This resistance changes with the magnitude of current and the strength of the magnetic field that is present in the gaps between each layer of the windings. An alternative leakage flux model is then presented, where the flux is modelled based on the combination of the reluctance of the core and the air surrounding the windings. Based on these theories, an iterative algorithm to calculate the resistance of the superconductor is developed. A new design of a 15kVA single phase full core superconducting transformer, operating in liquid nitrogen, is presented. The issues with building the superconducting transformer are outlined. First, a copper mockup of the superconducting transformer was designed where the mockup would have the same tape and winding dimensions as the superconducting transformer, which means the same core can be used for two different sets of windings. This led to designing a core that could be easily taken apart as well as reassembled. Construction of the core, the copper windings and the superconductor windings ensued. The process of cutting the core laminations, insulating the copper and superconductor tapes, and making the steel fasteners and terminations are described. The copper mockup and superconducting transformers was then tested under open circuit, short circuit, different load and endurance conditions at both liquid nitrogen and room temperatures. These test results were then compared with the those from two models. The comparison showed a significant inaccuracy in the reactances in the models. This introduced a correction factor into the superconductor model which ii made it more accurate. However, further work is required to explain and quantify the correction factors for the copper transformer model under different load conditions.

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36

Leung, Chi-ming. "Design consultancy vs design and build consultancy : present trends in the construction industry /." Hong Kong : University of Hong Kong, 1995. http://sunzi.lib.hku.hk/hkuto/record.jsp?B14038869.

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37

Achard, Timothée. "Techniques de calcul de gradient aéro-structure haute-fidélité pour l'optimisation de voilures flexibles." Thesis, Paris, CNAM, 2017. http://www.theses.fr/2017CNAM1140/document.

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L'optimisation multidisciplinaire (MDO) à base de gradients est efficace et très utilisée pour le dimensionnement structural d'ailes flexibles. Cependant, dans le contexte de simulations numériques haute-fidélité, le calcul efficace des gradients reste un défi majeur. L'objectif de ce travail est d'étudier les approches les mieux adaptées aux spécificités du calcul de sensibilité des efforts aéroélastiques par rapport à des paramètres structuraux.Deux techniques de calcul de gradient haute-fidélité adaptées aux systèmes aéroélastiques fortement couplés sont proposées. La technique la plus intrusive repose sur les formulations directe et adjointe qui nécessitent un effort d'implémentation logicielle substantiel. Alternativement, nous proposons une approche découplée et non-intrusive, moins lourde à implémenter et cependant capable de fournir une approximation précise des gradients. Ces deux techniques ont été intégrées dans le logiciel CFD elsA de l'Onera.La précision, l'efficience et l'applicabilité de ces méthodes sont démontrées sur le cas-test avion de transport civil Common Research Model (CRM). Nous résolvons un problème inverse dont l'objectif est de retrouver, en conditions de vol de croisière, une loi cible de vrillage voilure. Ces deux méthodes s'avèrent comparables en matière de précision et de coût. Elles offrent ainsi une souplesse supplémentaire de mise en œuvre en fonction du niveau d'intégration recherché dans le processus MDO
To improve the structural design of flexible wings, gradient based Multidisciplinary Design Optimization (MDO) techniques are effective and widely used. However, gradients calculation is not trivial and can be costly when high-fidelity models are considered. Our objective is to study different suitable approaches to compute gradients of aeroelastic loads with respect to structural design parameters.To this end, two high-fidelity aero-structure gradient computation techniques for strongly coupled aeroelastic systems are proposed. The most intrusive technique includes the well-established direct and adjoint formulations that require substantial implementation effort. In contrast, we propose an alternative uncoupled non-intrusive approach easier to implement and yet capable of providing accurate gradients approximations. Both techniques have been implemented in the Onera elsA CFD software.Accuracy, efficiency and applicability of these methods are demonstrated on the civil transport aircraft Common Research Model (CRM) test-case. More specifically, an inverse design problem is set up with the objective of matching an in-flight target twist law distribution. These two methods prove to be comparable in terms of accuracy and cost. Thus they offer additional operational flexibility depending on the level of integration sought in the MDO process

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Ferguson, A. J. L. "Dilution refrigerator : Design, construction and performance." Thesis, University of Ulster, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378638.

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Batzer, Rachel E. (Rachel Elizabeth). "Design and construction of a dynamometer." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68827.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.
"June 2011." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 20).
Access to a dynamometer is a useful tool for any electrical system where the motors must be selected from various suppliers and fully characterized. Motor suppliers usually provide a torque, speed, efficiency curve, but it frequently lacks complete motor characterization and includes motor controller losses in the total system loss. The dynamometer presented in this thesis is primarily designed for testing of high efficiency motors and motor controllers in the power and speed range requires for competition in the World Solar Challenge, a transcontinental race for solar electric vehicles. The testing specifications of a solar electric vehicles are uncommon among motor testing needs because it requires high torque, low power, high efficiency, and the only a small operating range. This thesis covers the design and construction of the dynamometer.
by Rachel E. Batzer.
S.B.

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Bibby, Lee. "Improving design management techniques in construction." Thesis, Loughborough University, 2003. https://dspace.lboro.ac.uk/2134/793.

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Recent years has seen a significant drive away from traditional procurement routes with contractors finding themselves with an increasing responsibility for control of design - a process they have had little experience in managing. They now have to adapt accordingly. The learning curve is steep, not least because many projects must now be delivered fast track while co-ordinating increasingly complex fabric and content of buildings without a platform of accepted good practice to manage the design process. This is a major factor preventing the UK construction industry from delivering projects on time, to budget and to the specified quality. There is a need to educate an increasing number of people in design management techniques to equip them to manage today's fast moving and demanding projects. However, many current design management tools are insufficiently developed for industry application. Therefore, to improve design management in the industry, current techniques must be modified to align them with the needs of the modern design manager. This research has developed and tested a training initiative aimed at improving design management practice within a major UK Design and Construct Contractor. It comprises a Design Management Handbook, Design Management Training, Team Support and Project Monitoring. The Design Management Handbook is the core of the training initiative. It addresses critical aspects of design management practice and provides design management tools. Training provides guidance to project teams on the tools and practices. In Team Support project teams are supported in the implementation of the new practices and tools to help embed new ways of working in company practice. Project Monitoring establishes the impact of the new practices on project performance to demonstrate that they are working and thus reinforce change. To establish the training initiative's effectiveness and key findings, the impact of the initiative on design management performance has been explored. The research has established which practices and tools were used, which were not, as well as an understanding the applicability and performance of each Handbook practice and tool. From this, barriers to implementing new design management tools in industry were identified and strategies developed in order to overcome such barriers.

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Jeffries, James R. "Construction implications of photolithography equipment design /." May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.

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Tisaj, David. "Design and construction of a tachometer." Thesis, Tisaj, David (2014) Design and construction of a tachometer. Other thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/25564/.

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The purpose of this report is to provide a guided tour of how everything was achieved by choosing the right parts, implementation and building, testing, results and of course to inspire future projects and students into making student level tachometers because they all come in different shapes and sizes. A microcontroller programmed using the Arduino software on Microsoft Windows in a combination of C and C++ was used to control various circuitry and brought the device to life with the Arduino software and a few external libraries. Various alterations and upgrades could be made to this device as this thesis only explores a fraction of the endless possibility of technologies, methods, programs, and electrical components. This thesis paper contains extensive research and will explore where tachometers came from and the current sensor technology used today such as the Hall Effect, generator, light reflected from a laser or an optical encoder that can determine position of a rotating device. The different technologies’ advantages and disadvantages will be looked into because in differing circumstances one might be better than the other. The specifications for this thesis are to measure and display the movement of a rotating machine in revolutions per minute or radians per second. The idea of the project was to make all the parts fit into a box and make it portable so getting the right battery was a cost versus function compromise. Tachometers are essentially used for measuring speed and can be in turn, control manually or automatically some aspect of the measured machine. Tachometers can be used for scheduling maintenance after certain mileage and therefore reducing costs over a machine’s lifetime. The basis for measurement is by using the Arduino’s interrupt function which will take quick and accurate time based measurements. The internal pull up resistor built into the Arduino’s board will ensure no false positives are recorded when a falling edge is present on the interrupt pin. Specifications from data sheets are examined in great detail to prevent damage to any of the components and part of the method is testing along the way and looking for problems and solutions.

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Ajayi, Saheed O. "Design, procurement and construction strategies for minimizing waste in construction projects." Thesis, University of the West of England, Bristol, 2017. http://eprints.uwe.ac.uk/30123/.

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The construction industry contributes the largest portion of waste to landfill, and it consumes a significant proportion of mineral resources excavated from nature. Due to adverse environmental impacts of waste generation, as well as financial gains associated with its minimization, waste intensiveness of the industry has remained a major concern across nations. This study investigates the design, procurement and construction strategies for waste minimization, using a dynamic approach. Apart from an investigation of the key and underlying measures for construction waste mitigation, the study considers the interrelationship between stages of projects' lifecycle. This is as activities carried out at an earlier stage are capable of engendering occurrences at later stages of the dynamic project delivery processes. Following the tenets of critical realism philosophy and exploratory sequential mixed method, the study combined qualitative and quantitative approaches at intensive and extensive stages respectively. At the early stage of the study, data were collected through literature review and focus group discussions with industry experts. Results of the qualitative study were used to develop a questionnaire, which was analysed using statistical approach and structural equation modelling. As a means of investigating the key drivers of waste minimization at a holistic level, a system dynamic model was developed to simulate the interplay and effects of different strategies that were confirmed through the previous process. The study suggests that design stage has the most decisive impacts on construction waste minimization. At this stage, the key dimensions for designing out waste include design for modern methods of construction, collaborative design process, design for standardisation and waste-efficient design documentation. Error-free design and involvement of contractors at early design stage are part of the critical success factors for designing out waste. With design being much important for waste minimization, competencies of design in terms of waste behavioural competency, design task proficiency, construction-related knowledge and inter-professional collaborative competency are essential for designing out waste. Materials procurement process could enhance waste minimization by considering its key dimensions for driving waste-efficient projects, which includes waste-efficient materials purchase management, suppliers' alliance and waste-efficient bill of quantity. Efficient materials take-off and take back scheme are confirmed as critical success factors for driving waste minimization through materials procurement processes. During construction activities, waste could be reduced through prefabrication and offsite technology, contractual requirements, maximisation of materials reuse and improved collaboration, among others. Prefabrication, supply chain alliance and collaborative procurement routes are confirmed as the critical success factors for reducing waste during construction process. Dynamic interplay among these sets of strategies suggests that notwithstanding the significance of the different measures during design, procurement and construction processes, prefabrication technology and collaborative procurement route are the holistic drivers of construction waste minimisation. The study implies that designers could effectively drive waste minimization through dimensional coordination and standardisation of design in line with standard materials supplies. In addition to the need for prefabrication and offsite technologies, increasing collaboration among project team is requisite to reducing waste generated by construction activities. By implementing the strategies suggested in the study, substantial proportion of construction waste would be diverted from landfill.

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Sobron, Alejandro. "Design and Testing of a Flight Control System for Unstable Subscale Aircraft." Thesis, Linköpings universitet, Fluida och mekatroniska system, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121819.

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The primary objective of this thesis was to study, implement, and test low-cost electronic flight control systems (FCS) in remotely piloted subscale research aircraft with relaxed static longitudinal stability. Even though this implementation was carried out in small, simplified test-bed aircraft, it was designed with the aim of being installed later in more complex demonstrator aircraft such as the Generic Future Fighter concept demonstrator project. The recent boom of the unmanned aircraft market has led to the appearance of numerous electronic FCS designed for small-scale vehicles and even hobbyist-type model aircraft. Therefore, the purpose was not to develop a new FCS from scratch, but rather to take advantage of the available technology and to examine the performance of different commercial off-the-shelf (COTS) low-cost systems in statically unstable aircraft models. Two different systems were integrated, calibrated and tested: a simple, gyroscope-based, single-axis controller, and an advanced flight controller with a complete suite of sensors, including a specifically manufactured angle-of-attack transducer. A flight testing methodology and appropriate flight-test data analysis tools were also developed. The satisfactory results are discussed for different flight control laws, and the controller tuning procedure is described. On the other hand, the different test-bed aircraft were analysed from a theoretical point of view by using common aircraft-design methods and conventional preliminary-design tools. The theoretical models were integrated into a flight dynamics simulator, which was compared with flight-test data obtaining a reasonable qualitative correlation. Possible FCS modifications are discussed and some future implementations are proposed, such as the integration of the angle-of-attack in the control laws.

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Petras, James P. "Prefabrication and the Construction Industry: An Examination of Design, Construction, and Efficiency." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1277120331.

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46

Roth, Fabian. "Explicit design, and adaptation in self-construction /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17005.

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Rehnberg, Adam. "Suspension design for off-road construction machines." Doctoral thesis, KTH, Fordonsdynamik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-33883.

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Construction machines, also referred to as engineering vehicles or earth movers, are used in a variety of tasks related to infrastructure development and material handling. While modern construction machines represent a high level of sophistication in several areas, their suspension systems are generally rudimentary or even nonexistent. This leads to unacceptably high vibration levels for the operator, particularly when considering front loaders and dump trucks, which regularly traverse longer distances at reasonably high velocities. To meet future demands on operator comfort and high speed capacity, more refined wheel suspensions will have to be developed. The aim of this thesis is therefore to investigate which factors need to be considered in the fundamental design of suspension systems for wheeled construction machines. The ride dynamics of wheeled construction machines are affected by a number of particular properties specific to this type of vehicle. The pitch inertia is typically high in relation to the mass and wheelbase, which leads to pronounced pitching. The axle loads differ considerably between the loaded and the unloaded condition, necessitating ride height control, and hence the suspension properties may be altered as the vehicle is loaded. Furthermore, the low vertical stiffness of off-road tyres means that changes in the tyre properties will have a large impact on the dynamics of the suspended mass. The impact of these factors has been investigated using analytical models and parameters for a typical wheel loader. Multibody dynamic simulations have also been used to study the effects of suspended axles on the vehicle ride vibrations in more detail. The simulation model has also been compared to measurements performed on a prototype wheel loader with suspended axles. For reasons of manoeuvrability and robustness, many construction machines use articulated frame steering. The dynamic behaviour of articulated vehicles has therefore been examined here, focusing on lateral instabilities in the form of “snaking” and “folding”. A multibody dynamics model has been used to investigate how suspended axles influence the snaking stability of an articulated wheel loader. A remote-controlled, articulated test vehicle in model-scale has also been developed to enable safe and inexpensive practical experiments. The test vehicle is used to study the influence of several vehicle parameters on snaking stability, including suspension, drive configuration and mass distribution. Comparisons are also made with predictions using a simplified linear model. Off-road tyres represent a further complication of construction machine dynamics, since the tyres’ behaviour is typically highly nonlinear and difficult to evaluate in testing due to the size of the tyres. A rolling test rig for large tyres has here been evaluated, showing that the test rig is capable of producing useful data for validating tyre simulation models of varying complexity. The theoretical and experimental studies presented in this thesis contribute to the deeper understanding of a number of aspects of the dynamic behaviour of construction machines. This work therefore provides a basis for the continued development of wheel suspensions for such vehicles.
QC 20110531

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Law, Gordon Ki-Wai. "Decision support system for construction cycle design." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26715.

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The objective of this thesis is to develop a conceptual design of a computerized environment for detailed design of construction activities associated with projects characterized by significant repetition. High-rise building construction is used as the example of repetitive construction projects. The construction cycle design of a typical floor structure is studied to gain an understanding of the difficulty and complexity involved in the activity design process. Modeling techniques currently used in construction planning, modeling techniques developed in the field of operations research, and assembly line balancing techniques used in industrial engineering are reviewed to determine their applicability for detailed construction cycle design. Using the concept of decision support systems developed in the fields of management science and knowledge engineering for solving ill-structured and ill-defined problems, a conceptual design of a decision support system for construction cycle design is developed.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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Morris, Jonathan. "Improving construction design : the lean thinking paradigm." Thesis, Cranfield University, 1999. http://dspace.lib.cranfield.ac.uk/handle/1826/3840.

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A study has been conducted into improving construction design through the application of the lean thinking paradigm. Its objective was to identify the issues relating to design efficiency and how a lean thinking approach might address these issues. The investigation consisted of examining work already undertaken in the field by other researchers"to identify the state of the art. The change order request system was examined to gain first insights into waste in construction design, and to gauge the size of the opportunity for the application of lean thinking. An Electronic Data Gathering Tool (EDGT) was then developed to allow further exploration of the design decision making process at the system / sub-system level. The EDGT was used on three live construction projects. From the data recorded a design planning tool, Design Decision Planner (DDP), was created to help improve control of the design process and lead to a more standardised approach to construction design. Standardising the approach to product development is an important component of lean thinking. The main recommendations for making construction design lean are: Use DDP to plan and improve control of the design decision making process, assign design responsibility and to make the process more transparent. 2. Measuring progress against planned design is a useful process metric. 3. Improve the designer's cost and programme visibility when choosing between design options. 4. Redefine the role of the quantity surveyor from cost controller to value for money assessor. The role needs to be better integrated into the design process to reach its full potential. 5. Need to develop more rigorous methods of assessing the buildability of design options. This problem could be eased in the short-term by incorporating construction professionals into the early design phases. 6. Designers need to use more process reason drivers when choosing between design options, not just functional criteria. 7. The change order request system could be redesigned to identify the root causes of contract issue design changes and, hence, improve the design decision making process.

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Brouqueyre, Laurent. "Hydro-acoustic therapy : design, construction and testing." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/18215.

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Dissertations / Theses on the topic 'Avionics Design and construction'

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