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Etude et développement de tableaux non diffractants pour la conception de systèmes imageurs spécialisés / Analysis and development of non diffracting arrays for the design of specialized imaging systemsPiponnier, Martin 17 December 2012 (has links)
La capacité actuelle d’accéder à des détecteurs très performants et de faible coût amène la communauté des concepteurs de systèmes optiques à un changement de paradigme. Plutôt que de réaliser des caméras généralistes, aptes à réaliser un grand nombre de missions d’observation différentes, il est maintenant de plus en plus courant de développer des systèmes imageurs adaptés à une seule mission et/ou à une seule classe d’objets. Prendre en compte ces connaissances a priori sur la scène et la mission, au moment de la conception, permet d’envisager des systèmes plus simples, mais aussi dotés de nouvelles compétences. L'objectif de la thèse est d'explorer les potentialités des tableaux non diffractants pour la conception de systèmes imageurs spécialisés. Pour cette étude nous considérons l'environnement des drones aéroportés de faible capacité d'emport pour lesquels les systèmes imageurs embarqués doivent être simples et robustes. Nous considérons de plus que la mission du système imageur est de détecter les obstacles. Pour cela, il doit délivrer une information 3D sur la scène observée. Dans un premier temps, j'ai analysé les propriétés d'imagerie du système imageur constitué d'un composant non diffractant et d'un détecteur matriciel. L'analyse comparative de deux composants, l'axicon et le tableau non diffractant, m'a permis de montrer que c'est le second composant qui est le mieux adapté pour remplir ce type de mission. J'ai ensuite réalisé un système imageur de démonstration, ce qui m'a permis au final de mettre en évidence sa capacité à faire de l'imagerie 3D. Cette étude a montré que les tableaux non diffractants ont un très fort potentiel pour réaliser un système imageur simple, robuste et dédié à l'imagerie 3D. Ce travail doit être poursuivi en partenariat avec des industriels pour appliquer la démarche de conception à une mission précise et transformer ce travail théorique en un système industrialisable. / Currently, detectors with high performances and a low cost are available and lead the community of optical designers to a new paradigm. Instead of designing generalist cameras, suitable for fulfilling a high number of different observation missions, it is now more and more common to develop imaging systems adapted to a unique mission and/or a unique object class. Taking this a priori knowledge on the observed scene or on the mission into account, at the beginning of the design process, allows us to consider simpler imaging systems with new properties. The aim of this thesis is to investigate the possibilities of nondiffracting array for the design of specialized imaging systems. For this study we consider the environment of unmanned aerial vehicles with a small payload capacity, for which embedded imaging systems must be simple and robust. We consider in addition that the mission of the imaging system is to detect obstacles. To do this, it must provide a 3D information on the observed scene. At first, I have analysed the properties of the imaging system composed by a nondiffracting optical device and a focal plane array. The comparison between two devices, axicon and nondiffracting arrays, allowed me to show that the second one is best suited for achieving this kind of mission. Then, I have made a practical implementation of such an imaging system. Finally, I have used it to demonstrate the 3D imaging property. This study has demonstrated the potential of nondiffracting array to design a simple and robust imaging system dedicated to 3D imaging. This work must be continued in partnership with the industry to apply the co-design process to a more precise mission, transforming this way this theoretical work into an industrial prototype.
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Pathologies fonctionnelles mandibulaires, de l'outil numérique à la recherche applicative / Mandibular functional pathologies, numerical tool for applicative researchJaisson, Maxime 20 September 2013 (has links)
Le principal objectif de cette thèse a été d'utiliser des outils numériques en sciences pour l'ingénieur dans le cadre d'applications médicales dont le but était de mieux appréhender la pathogénie des troubles fonctionnels, et de développer de nouvelles techniques thérapeutiques (sphère orofaciale). Dans un premier temps l'outil éléments finis s'appuyant sur des données rhéologiques a été utilisé afin de mieux appréhender la problématique de l'articulation temporo-mandibulaire. Les résultats numériques associés à une captation du mouvement de la mandibule ont permis de mieux comprendre, au sens, mécanique certains aspects mandibulaires. Par ailleurs, dans un deuxième temps, l'outil CAO a été mis en œuvre afin d'aider la préparation de la chirurgie maxillofaciale. Cette nouvelle approche a permis de mettre en œuvre une nouvelle méthodologie en chirurgie des tumeurs interruptrices en améliorant (i) le contrôle du résultat esthétique, (ii) la réduction du temps opératoire et (iii) le respect de la bonne congruence de l'ATM. / The main objective of this thesis was to use numerical engineering softwares in the framework of medical applications whose purpose was to understand the pathogenesis functional disorders, and to develop new therapeutic techniques (orofacial sphere). At first, finite elements tools based on rheological data has been used to understand the problem of TMJ. Numerical results associated with motion capture of the mandible have a better understanding the mandibular mechanical aspects. Moreover, in a second step, the CAD tools implemented to assist the preparation of the maxillofacial surgery. This new approach allowed a new methodology surgery interrupter tumors improving (i) controling the esthetic result, (ii) reducing the operating time and (iii) respecting a good TMJ congruence.
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Nytten av å jamføre målkoordinatdata mot digitale kartgrunnlag for å øke nøyaktigheten ved indirekte bekjempning / The utility of merging target data coodinates with digital map tools in order to increase accuracy during indirect fires”Olssen, Andreas January 2016 (has links)
Evnen til å ta ut gode nok målkoordinater på landmål for engasjement med GPS-INS styrte våpen har siden innføringen av denne våpentypen på 90-tallet vært et omdiskutert tema. GNSS system sin egnethet for understøttelse av militære operasjoner har i nyere tid blitt gjenstand for diskusjon, da systemets unøyaktighet og sårbarhet er et faktum. Det er i denne oppgaven ført sammen resultater fra mest naturvitenskaplige metoder med noen få innslag av samfunnsvitenskapelig metode for å søke å finne ut om, og i så fall hvilken nytte, en operatør som tar ut målkoordinater med FOI2000, for bekjempelse ved bruk av GPS-INS styrt ammunisjon, har av å jamføre disse dataene med digitale kartverktøy. Datainnsamlingen er gjort ved litteraturstudier av naturvitenskaplig faglitteratur, publiserte artikler både fra industri, forskermiljø, offisielle instanser og studiebesøk ved VRICON og TELEPLAN. I tillegg brukes forfatterens egen erfaring til å dra veksler opp mot moderne aktuelle stridsmiljø. Resultatet viser at jamføring med digitale terrengmodeller gir under mange situasjoner gode muligheter for å minske unøyaktigheten i uttak av målkoordinater for bekjempning med GPS-INS styrte våpen. Imidlertid gir satellittbildegrunnlag og 3D modeller av terreng begge gode muligheter for optimering av måldata, på hver sin måte der den ene er ikke nødvendigvis bedre enn den andre men kan utfylle hverandre. Moderne satellittbilder er mest nøyaktige i horisontalplanet, mens 3D modeller har en mye bedre nøyaktighet i vertikal og 3D dimensjonen. Slutningen i oppgaven er at personell som jobber mer målkoordinatuttak med FOI2000 har store fordeler ved å bruke FACNAV med digitalt terrenggrunnlag bestående av både satellittbilder og 3D terreng modell, da de utfyller hverandre. Dette gir de beste forutsetninger for å produsere de mest nøyaktige måldata gjennom å kombinere og optimere dataene ved bruk av alle tre system. En annen viktig observasjon er dog 3D modellen store muligheter for støtte innenfor planlegging av oppdrag og det å gjøre seg kjent i lendet i et aktuelt operasjonsområde. / Since the invention of coordinate dependent weapons in the nineties, the ability to provide accurate land target coordinates for engagement has been a topic on discussion. GNSS systems unquestioned support to military operations has in the recent years been challenged by the obvious vulnerability the GNSS systems regarding its in-accuracy and potential vulnerability. During this paper results from both scientific methods and some social scientific methods have been merged in order to reveal whether, and if so, to what extent, an operator pulling target coordinates in a battlefield with use of the standard Norwegian observation instrument FOI2000 have use of merging the FOI2000 data with FACNAV digital map tools such as satellite imagery and/or a 3D terrain model. This is meant to acquire more accurate employment of coordinate dependent weapons (GPS-INS guided bombs and grenades) with focus on an increased target coordinate accuracy. The collection of data is done through literature studies of scientific books and published papers from industries, research societies, official institutions and own research-tours at VRICON and Teleplan Globe. Also included in the discussion is the author’s own experiences from modern areas of operation. Results show that in many scenarios the target coordinate will get an increased accuracy when merged with FACNAVs satellite imagery and/or 3D terrain. But this does not apply to all scenarios. Both satellite imageries and 3D models provide increased accuracy on the target coordinates when merged, however none is necessary better than the other, but they kind of have different qualities. Modern satellite imageries have better accuracy in the horizontal domain, while a 3D model has the best accuracy in the vertical and 3D domain. The conclusion of the work is that an operator pulling target coordinates with a FOI2000 takes great advantage of merging the target data with FACNAV´s satellite imagery and a 3D terrain model. The best target data will most likely be produced when utilizing all three systems. However, another discovery is the potential of a digital 3D model potential to support in operations planning and terrain knowledge acquirement in unfamiliar operation areas that military units are going into.
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