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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Development of a 3D multi-camera measurement system based on image stitching techniques applied for dynamic measurements of large structures /

Sabino, Danilo Damasceno. January 2018 (has links)
Orientador: João Antonio Pereira / Resumo: O objetivo específico deste trabalho é estender as capacidades da técnica de rastreamento de pontos em 3 dimensões (three-dimensional point tracking – 3DPT) para identificar as características dinâmicas de estruturas grandes e complexas, tais como pás de turbina eólica. Um sistema multi-camera (composto de múltiplos sistemas de estéreo visão calibrados independentemente) é desenvolvido para obter alta resolução espacial de pontos discretos a partir de medidas de deslocamento sobre grandes áreas. Uma proposta de técnica de costura é apresentada e empregada para executar o alinhamento de duas nuvens de pontos, obtidas com a técnica 3DPT, de uma estrutura sob excitação dinâmica. Três diferentes algoritmos de registro de nuvens de pontos são propostos para executar a junção das nuvens de pontos de cada sistema estéreo, análise de componentes principais (Principal Component Analysis - PCA), decomposição de valores singulares (Singular value Decomposition - SVD) e ponto mais próximo iterativo (Iterative Closest Point - ICP). Além disso, análise modal operacional em conjunto com o sistema de medição multi-camera e as técnicas de registro de nuvens de pontos são usadas para determinar a viabilidade de usar medidas ópticas (e.g. three-dimensional point tracking – 3DPT) para estimar os parâmetros modais de uma pá de gerador eólico comparando seus resultados com técnicas de medição mais convencionais. / Abstract: The specific objective of this research is to extend the capabilities of three-dimensional (3D) Point Tracking (PT) to identify the dynamic characteristics of large and complex structures, such as utility-scale wind turbine blades. A multi-camera system (composed of multiple independently calibrated stereovision systems) is developed to obtain high spatial resolution of discrete points from displacement measurement over very large areas. A proposal of stitching techniques is presented and employed to perform the alignment of two point clouds, obtained with 3DPT measurement, of a structure under dynamic excitation. The point cloud registration techniques are exploited as a technique for dynamic measuring (displacement) of large structures with high spatial resolution of the model. Three different image registration algorithms are proposed to perform the junction of the points clouds of each stereo system, Principal Component Analysis (PCA), Singular value Decomposition (SVD) and Iterative Closest Point (ICP). Furthermore, operational modal analysis in conjunction with the multi-camera measurement system and registration techniques are used to determine the feasibility of using optical measurements (e.g. three-dimensional point tracking (3DPT)) to estimate the modal parameters of a utility-scale wind turbine blade by comparing with traditional techniques. / Doutor
52

Development of a 3D multi-camera measurement system based on image stitching techniques applied for dynamic measurements of large structures / Desenvolvimento de um sistema de medição 3D multi-cameras com base em técnicas de costura de imagens aplicado para medições dinâmicas de grandes estruturas

Sabino, Danilo Damasceno 01 February 2018 (has links)
Submitted by DANILO DAMASCENO SABINO (engdanilosabino@gmail.com) on 2018-07-03T16:00:40Z No. of bitstreams: 1 DaniloSabino_TeseVersaoFinal.pdf: 4134991 bytes, checksum: 888a0a610949d5417be468fa2b94c7c8 (MD5) / Rejected by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br), reason: Danilo, seu trabalho foi redigido em língua inglesa, mas é preciso inserir o título em português no campo "título em outro idioma". Tentamos contato por e-mail mas sem resposta. Assim, solicitamos que refaça a submissão do seu trabalho com essa informação. on 2018-07-06T14:47:31Z (GMT) / Submitted by DANILO DAMASCENO SABINO (engdanilosabino@gmail.com) on 2018-09-24T22:07:38Z No. of bitstreams: 1 DaniloSabino_TeseVersaoFinal.pdf: 4134991 bytes, checksum: 888a0a610949d5417be468fa2b94c7c8 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-09-25T11:47:26Z (GMT) No. of bitstreams: 1 sabino_dd_dr_ilha.pdf: 4134991 bytes, checksum: 888a0a610949d5417be468fa2b94c7c8 (MD5) / Made available in DSpace on 2018-09-25T11:47:26Z (GMT). No. of bitstreams: 1 sabino_dd_dr_ilha.pdf: 4134991 bytes, checksum: 888a0a610949d5417be468fa2b94c7c8 (MD5) Previous issue date: 2018-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo específico deste trabalho é estender as capacidades da técnica de rastreamento de pontos em 3 dimensões (three-dimensional point tracking – 3DPT) para identificar as características dinâmicas de estruturas grandes e complexas, tais como pás de turbina eólica. Um sistema multi-camera (composto de múltiplos sistemas de estéreo visão calibrados independentemente) é desenvolvido para obter alta resolução espacial de pontos discretos a partir de medidas de deslocamento sobre grandes áreas. Uma proposta de técnica de costura é apresentada e empregada para executar o alinhamento de duas nuvens de pontos, obtidas com a técnica 3DPT, de uma estrutura sob excitação dinâmica. Três diferentes algoritmos de registro de nuvens de pontos são propostos para executar a junção das nuvens de pontos de cada sistema estéreo, análise de componentes principais (Principal Component Analysis - PCA), decomposição de valores singulares (Singular value Decomposition - SVD) e ponto mais próximo iterativo (Iterative Closest Point - ICP). Além disso, análise modal operacional em conjunto com o sistema de medição multi-camera e as técnicas de registro de nuvens de pontos são usadas para determinar a viabilidade de usar medidas ópticas (e.g. three-dimensional point tracking – 3DPT) para estimar os parâmetros modais de uma pá de gerador eólico comparando seus resultados com técnicas de medição mais convencionais. / The specific objective of this research is to extend the capabilities of three-dimensional (3D) Point Tracking (PT) to identify the dynamic characteristics of large and complex structures, such as utility-scale wind turbine blades. A multi-camera system (composed of multiple independently calibrated stereovision systems) is developed to obtain high spatial resolution of discrete points from displacement measurement over very large areas. A proposal of stitching techniques is presented and employed to perform the alignment of two point clouds, obtained with 3DPT measurement, of a structure under dynamic excitation. The point cloud registration techniques are exploited as a technique for dynamic measuring (displacement) of large structures with high spatial resolution of the model. Three different image registration algorithms are proposed to perform the junction of the points clouds of each stereo system, Principal Component Analysis (PCA), Singular value Decomposition (SVD) and Iterative Closest Point (ICP). Furthermore, operational modal analysis in conjunction with the multi-camera measurement system and registration techniques are used to determine the feasibility of using optical measurements (e.g. three-dimensional point tracking (3DPT)) to estimate the modal parameters of a utility-scale wind turbine blade by comparing with traditional techniques.
53

Dimensionamento e gestão de energia solar fotovoltaica para aplicação em sistemas automatizados isolados da rede elétrica

Borges, Leandro da Motta 27 September 2013 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-03-04T10:45:15Z No. of bitstreams: 1 leandrodamottaborges.pdf: 2242416 bytes, checksum: 10ac80b836250ec857dfe2dc8f819119 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T01:49:45Z (GMT) No. of bitstreams: 1 leandrodamottaborges.pdf: 2242416 bytes, checksum: 10ac80b836250ec857dfe2dc8f819119 (MD5) / Made available in DSpace on 2016-04-24T01:49:45Z (GMT). No. of bitstreams: 1 leandrodamottaborges.pdf: 2242416 bytes, checksum: 10ac80b836250ec857dfe2dc8f819119 (MD5) Previous issue date: 2013-09-27 / Este trabalho apresenta o estudo, dimensionamento e gestão de um sistema solar fotovoltaico isolado da rede elétrica para alimentar cargas de equipamentos de automação industrial. Um exemplo de aplicação são unidades de comando e sinalização ferroviária que, em alguns casos, são comandadas por relés e, mais atualmente, sendo substituídas por Controladores Lógico Programáveis. No sistema solar fotovoltaico isolado, o excedente de energia elétrica produzida nos painéis solares fotovoltaicos é armazenado em baterias eletroquímicas estacionárias de chumbo-ácido para posterior aproveitamento durante o período noturno e de baixa produção de eletricidade. Esse tipo de bateria apresenta efeito de memória, não pode sofrer descarga profunda ou ser submetida a tensões elevadas. Assim, este trabalho visa especificar e dimensionar um sistema solar fotovoltaico para aplicações em cargas de automação industrial isolados da rede elétrica, bem como assegurar elevada vida útil da bateria eletroquímica de chumbo-ácido sem prejudicar o rastreamento de máxima potência dos painéis solares fotovoltaicos. Para isso, uma estratégia de gestão de energia possibilita alterar o controle do conversor CC-CC que realiza a interconexão entre os painéis solares fotovoltaicos e a bateria eletroquímica. Resultados de simulação computacional apontam para o bom desempenho conceitual do sistema e seu potencial para a aplicação pretendida. / This work presents the study, design and management of a stand-alone photovoltaic system to feed industrial automation load. E examples of application are railway signaling unit controls, which in some cases are controlled by electromechanical relays and more currently being replaced by programmable logical controllers. In a stand-alone photovoltaic system, the excess of electricity produced in the photovoltaic panels is stored in lead-acid stationary electrochemical batteries for later use during the night and low electricity production periods. This kind of battery presents memory effect, cannot have deep discharge or be subjected to high voltages. Thus, this work aims to specify and size a solar photovoltaic system for applications in industrial automation loads isolated from the grid, as well as ensuring longer lifetime to electrochemical battery of lead-acid without harming the maximum power tracker of photovoltaic panels. For this, a strategy for changing power management enables the control of DC-DC converter that performs the interconnection of photovoltaic panels and electrochemical battery. Results of computer simulation indicate the good conceptual performance of the system and its potential for the intended application.
54

Energy management and control for hybrid renewable energy sources in rural area / Gestion de l'énergie et de contrôle pour les hybrides sources d'énergie renouvelables en zone rurale

Ahmed, Rana 27 November 2015 (has links)
Cette thèse propose principalement, un algorithme État-Flow MPPT basé P&O, amélioré avec deux degrés de liberté, dans lequel le système événementiel (MPPT) de comportement est modélisé par le décrivant en terme de transition entre les états, sous certaines conditions. Secondairement, un algorithme étendu MPPT, base d'exploitation en parallèle de l'état-débit est en outre proposé d'être une solution difficile pour le contrôle indépendant du système hybride, où la caractéristique de contrôle continu peut se présenter au cours d'un certain état de travail tout en discrète, est indiquée le long des transitions d'état. Deux configurations possibles pour le système hybride sont proposées : deux convertisseurs DC/DC séparés, et un convertisseur de sortie unique à double entrée (DISO) de configurations. Enfin, il est proposé, un comportement du système DC modélisation utilisant État-Flow, menant à l'ensemble de la conception de la stratégie de commande qui concernent RES MPPT, RES et la coordination BESS, la stabilité du système d'alimentation et de régulation de la tension du bus DC. La simulation et les résultats expérimentaux valident l'efficacité et l'applicabilité de l'algorithme proposé. Les deux résultats montrent la supériorité du MPPT basé proposé État-Flow pour réduire les oscillations de puissance RESs à l'état d'équilibre dans diverses conditions d'exploitation, en plus de son démarrage plus rapide, et l’opération de transition sans divergence de la MPP, selon des conditions météorologiques variables. / This thesis primarily proposes, an improved P&O based State-Flow MPPT algorithm featuring two degree of freedom, in which the event driven system (MPPT) behaviour is modelled by describing it in terms of transitions among states under certain conditions. Secondarily, an extended parallel operating State-Flowbased MPPT algorithm is further proposed to be a challenging solution for the independent control of the hybrid system, where continuous control characteristic can present during a certain working state while discrete one is indicated along state transitions. Two possible configurations for the hybrid system are proposed; two separate DC/DC converters and dual input single output converter (DISO) configurations. Finally it is proposed, DC system behaviour modelling using State-Flow leading to the whole control strategy design which concern RESs MPPT, RESs and BESS coordination, power system stability and DC bus voltage regulation.Simulation and experimental results validate the effectiveness and applicability of the proposed algorithm, both results show the superiority of the proposed State-Flow based MPPT in reducing the RESs power oscillations at steady-state in various operating conditions in addition to its faster start-up and transition operation without divergence from the MPP during sudden varying weather conditions.
55

Systém napájení domácnosti z obnovitelných zdrojů energie / Power Supply System for Housis Using Renewable Resources

Gálus, Matej January 2011 (has links)
The aim of this thesis is to describe the advantages of simultaneous utilization of photovoltaic and wind electricity in an autonomous system, supplying the household with electricity without connection to the electrical grid. The most used methods of connecting photovoltaic modules and wind generators to chemical batteries are discussed. Several maximum power point tracking methods and their properties are described. A block schematic diagram of an autonomous off-grid system utilizing chemical accumulators is proposed. The system also contains an inverter producing standard mains voltage 230 VAC to supply common household appliances. A Quasi-Square Wave converter topology was chosen for all three power converters. An experimental 180 W output power QSW converter with one controllable switch was designed, simulated with Pspice, manufactured and tested to verify the efficiency of the topology. Excellent agreement was found between predicted and measured efficiency at full output power. Efficiency for reliable operation varies between 89% and 92,2% at full power and depends mainly power inductor and MOSFET used. After successful evaluation of QSW topology, the power converters for the main system were designed. Because of higher power, the converters were designed as four-phase, whereas each phase contains two controllable switches to boost efficiency mainly in low-power area. The most critical and difficult part of the project was to design the mixed-signal control sections for the converters to ensure proper switching of two controllable MOSFETs in each phase. For user interactivity, main control board with graphic LC display, Ethernet module and SD memory card slot was also manufactured.
56

Implementation of DC-DC converter with maximum power point tracking control for thermoelectric generator applications

Jahanbakhsh, David January 2012 (has links)
A heavy duty vehicle looses approximately 30-40 % of the energy in the fuel as waste heat through the exhaust system. Recovering this waste heat would make the vehicle meet the legislative and market demands of emissions and fuel consumption easier. This recovery is possible by transforming the waste heat to electric power using a thermoelectric generator. However, the thermoelectric generator electric characteristics makes direct usage of it unprotable, thus an electric power conditioner is necessary. First a study of dierent DC-DC converters is presented, based on that the most suitable converter for thermoelectric application is determined. In order to maximize the harvested power, maximum power point tracking algorithms have been studied and analyzed. After the investigation, the single ended primary inductor converter was simulated and implemented with a perturb and observe algorithm, and the incremental conductance algorithm. The converter was tested with a 20 W thermoelectric generator, and evaluated.The results show that the incremental conductance is more robust and stable compared to the perturb and observe algorithm. Further on, the incremental conductance also has a higher average eciency during real implementation.
57

Robust Extremum Seeking Control Design

Odoemene, Daniel Okezuo Tarasius January 2022 (has links)
No description available.
58

Contribution au Dimensionnement et à la Commande d’un Générateur de type Cascade de Machines Asynchrones à Double Alimentation / Contribution to the Sizing and Control of the Cascaded Doubly Fed Induction Generator

El achkar, Maria 12 December 2016 (has links)
Le travail présenté dans cette thèse est une contribution au dimensionnement et à la commande d’un générateur de type Cascade de Machines Asynchrones à Double Alimentation. Le modèle de la machine pour les simulations est basé sur une représentation modulaire qui découle du modèle de Park de deux machines asynchrones doublement alimentées distinctes, en respectant deux systèmes de référence. Le modèle dynamique est ensuite étendu pour décrire la machine dans un repère unifié. Cette représentation est cruciale pour le dimensionnement de la machine et la synthèse de la commande. Le domaine de fonctionnement de la cascade en régime permanent est exploré. Une méthode analytique générique est proposée pour établir les plages de puissances active-réactive. Les courbes limites sont définies par rapport aux grandeurs nominales de la machine. L’étude prend en compte l’effet de saturation du circuit magnétique. Il est prouvé que la capacité en puissance de la machine est déterminée par les valeurs maximales des courants statoriques et peut être soumise à plusieurs limitations. L’approche analytique est testée et validée par des mesures expérimentales. Deux cas sont considérés pour la commande de la cascade : un générateur raccordé au réseau et un générateur autonome. Pour la connexion au réseau l’application visée est les éoliennes de grande puissance. Une nouvelle méthode pour l’extraction de la puissance maximale d’une éolienne à vitesse variable est proposée. Le système est contrôlé dans le but de fournir une puissance maximale quasi-constante indépendamment des fluctuations du vent. En plus de l’optimisation de la puissance, le facteur de puissance est également ajusté selon les normes de raccordement standard imposées par les services système, et les limites de fonctionnement de l’unité intégrée. Une commande vectorielle sans capteur de tension, basée sur une orientation suivant un flux virtuel, est appliquée pour la régulation découplée des puissances active et réactive. Pour le fonctionnement en mode isolé, l’application visée est la génération électrique pour système avionique embarqué. Deux réseaux de distribution sont traités : réseau AC à fréquence fixe et réseau DC. Dans les deux cas, la commande est élaborée dans le but de maintenir une tension de sortie constante. Le fonctionnement de la cascade alimentant une charge triphasée déséquilibrée est également étudié. Des schémas de contrôle servant à la compensation du déséquilibre des tensions statoriques sont développés. Deux méthodes de compensation sont proposées : l’une basée sur le principe de deux repères tournants et l’autre sur un correcteur répétitif. Les approches présentées sont validées par simulation avec Matlab/Simulink et par expérimentation. / This thesis is a contribution to the power sizing and the control of a Cascaded Doubly Fed Induction Generator (CDFIG). The machine model for simulation is based on a modular representation, derived from the Park model of two distinct Doubly Fed Induction Machines expressed in their own reference frames. The dynamic model of the cascaded machine is then extended to be described in a unified reference frame. This representation is convenient for the sizing of the machine and for the design of the controller. The steady state power operating margins of the cascaded machine are investigated. A generic analytic method is suggested to derive the active-reactive power domain. The limit curves are defined in terms of the rated quantities of the machine. The study takes into account the magnetic circuit saturation effect. It is proven that the power capability of the machine is determined by the stator current maximum values and is subject to several limitations. The analytical approach is tested and validated by experimental measurements. The CDFIG is controlled in grid-connected and standalone operation modes. In grid-connected application, the attention is paid to high power wind generation systems. A new maximum power tracking of a variable speed wind turbine is suggested. The generating plant is carried to provide a quasi-constant maximum power regardless wind fluctuations. In addition to active power optimization the power factor is adjusted according to the grid code requirements and the operating domain of the integrated unit. A virtual flux oriented vector control is applied for the decoupled regulation of active and reactive powers, leading to grid voltage sensorless operation. In standalone operating mode, the study treats in particular the embedded aircraft power system generation. Two distribution networks are considered: constant frequency AC network and DC network. In both cases, the control aims to maintain a constant output voltage. The operation of the CDFIG supplying unbalanced three-phase load is further explored. Control schemes to cope with unbalanced stator voltage conditions are developed. Two compensation methods are elaborated: the first dealing with dual rotating frames and the second is based on repetitive controller. Simulations with Matlab/Simulink software and experiments validate the control approaches.
59

Contribution to adaptative sliding mode, fault tolerant control and control allocation of wind turbine system / Contribution à la commande par modes glissants adaptative et tolérantes aux défauts : Application au système éolien

Liu, Xinyi 25 November 2016 (has links)
Les principaux défis pour le déploiement de systèmes de conversion de l'énergie éolienne est de maximiser la puissance électrique produite, malgré les variations des conditions météorologiques, tout en minimisant les coûts de fabrication et de maintenance du système. L'efficacité de la turbine éolienne est fortement dépendante des perturbations de l'environnement et des paramètres variables du système, tels que la vitesse du vent et l'angle de tangage. Les incertitudes sur le système sont difficiles à modéliser avec précision alors qu'ils affectent sa stabilité.Afin d'assurer un état de fonctionnement optimal, malgré les perturbations, le commande adaptative peut jouer un rôle déterminant. D'autre part, la synthèse de commandes tolérantes aux défauts, capables de maintenir les éoliennes connectées au réseau après la survenance de certains défauts est indispensable pour le bon fonctionnement du réseau. Le travail de cette thèse porte sur la mise en place de lois de commande adaptatives et tolérantes aux défauts appliqués aux systèmes de conversion de l'énergie éolienne. Après un état de l'art, les contributions de la thèse sont :Dans la première partie de la thèse, un modèle incertain non linéaire du système de conversion d'énergie éolienne avec un générateur à induction à double alimentation est proposé. Une nouvelles approches de commande adaptative par mode glissant est synthétisée et ensuite appliquée pour optimiser l'énergie issue de l'éolienne.Dans la deuxième partie, une nouvelle commande par modes glissants tolérante aux défauts et basée sur les modes glissants intégrales est présentée. Puis, cette méthode est appliquée afin de forcer la vitesse de la turbine éolienne à sa valeur optimale en prenant en compte des défauts qui surviennent sur l'actionneur. / The main challenges for the deployment of wind energy conversion systems (WECS) are to maximize the amount of good quality electrical power extracted from wind energy over a significantly wide range of weather conditions and minimize both manufacturing and maintenance costs. Wind turbine's efficiency is highly dependent on environmental disturbances and varying parameters for operating conditions, such as wind speed, pitch angle, tip-speed ratio, sensitive resistor and inductance. Uncertainties on the system are hard to model exactly while it affects the stability of the system. In order to ensure an optimal operating condition, with unknown perturbations, adaptive control can play an important role. On the other hand, a Fault Tolerant Control (FTC) with control allocation that is able to maintain the WECS connected after the occurrence of certain faults can avoid major economic losses. The thesis work concerns the establishment of an adaptive control and fault diagnosis and tolerant control of WECS. After a literature review, the contributions of the thesis are:In the first part of the thesis, a nonlinear uncertain model of the wind energy conversion system with a doubly fed induction generator (DFIG) is proposed. A novel Lyapunov-based adaptive Sliding Mode (HOSM) controller is designed to optimize the generated power.In the second part, a new output integral sliding mode methodology for fault tolerant control with control allocation of linear time varying systems is presented. Then, this methodology has been applied in order to force the wind turbine speed to its optimal value the presence of faults in the actuator.
60

Geometrische und stochastische Modelle zur Verarbeitung von 3D-Kameradaten am Beispiel menschlicher Bewegungsanalysen / Geometric and stochastic models for the processing of 3D camera data within the context of human motion analyses

Westfeld, Patrick 15 June 2012 (has links) (PDF)
Die dreidimensionale Erfassung der Form und Lage eines beliebigen Objekts durch die flexiblen Methoden und Verfahren der Photogrammetrie spielt für ein breites Spektrum technisch-industrieller und naturwissenschaftlicher Einsatzgebiete eine große Rolle. Die Anwendungsmöglichkeiten reichen von Messaufgaben im Automobil-, Maschinen- und Schiffbau über die Erstellung komplexer 3D-Modelle in Architektur, Archäologie und Denkmalpflege bis hin zu Bewegungsanalysen in Bereichen der Strömungsmesstechnik, Ballistik oder Medizin. In der Nahbereichsphotogrammetrie werden dabei verschiedene optische 3D-Messsysteme verwendet. Neben flächenhaften Halbleiterkameras im Einzel- oder Mehrbildverband kommen aktive Triangulationsverfahren zur Oberflächenmessung mit z.B. strukturiertem Licht oder Laserscanner-Systeme zum Einsatz. 3D-Kameras auf der Basis von Photomischdetektoren oder vergleichbaren Prinzipien erzeugen durch die Anwendung von Modulationstechniken zusätzlich zu einem Grauwertbild simultan ein Entfernungsbild. Als Einzelbildsensoren liefern sie ohne die Notwendigkeit einer stereoskopischen Zuordnung räumlich aufgelöste Oberflächendaten in Videorate. In der 3D-Bewegungsanalyse ergeben sich bezüglich der Komplexität und des Rechenaufwands erhebliche Erleichterungen. 3D-Kameras verbinden die Handlichkeit einer Digitalkamera mit dem Potential der dreidimensionalen Datenakquisition etablierter Oberflächenmesssysteme. Sie stellen trotz der noch vergleichsweise geringen räumlichen Auflösung als monosensorielles System zur Echtzeit-Tiefenbildakquisition eine interessante Alternative für Aufgabenstellungen der 3D-Bewegungsanalyse dar. Der Einsatz einer 3D-Kamera als Messinstrument verlangt die Modellierung von Abweichungen zum idealen Abbildungsmodell; die Verarbeitung der erzeugten 3D-Kameradaten bedingt die zielgerichtete Adaption, Weiter- und Neuentwicklung von Verfahren der Computer Vision und Photogrammetrie. Am Beispiel der Untersuchung des zwischenmenschlichen Bewegungsverhaltens sind folglich die Entwicklung von Verfahren zur Sensorkalibrierung und zur 3D-Bewegungsanalyse die Schwerpunkte der Dissertation. Eine 3D-Kamera stellt aufgrund ihres inhärenten Designs und Messprinzips gleichzeitig Amplituden- und Entfernungsinformationen zur Verfügung, welche aus einem Messsignal rekonstruiert werden. Die simultane Einbeziehung aller 3D-Kamerainformationen in jeweils einen integrierten Ansatz ist eine logische Konsequenz und steht im Vordergrund der Verfahrensentwicklungen. Zum einen stützen sich die komplementären Eigenschaften der Beobachtungen durch die Herstellung des funktionalen Zusammenhangs der Messkanäle gegenseitig, wodurch Genauigkeits- und Zuverlässigkeitssteigerungen zu erwarten sind. Zum anderen gewährleistet das um eine Varianzkomponentenschätzung erweiterte stochastische Modell eine vollständige Ausnutzung des heterogenen Informationshaushalts. Die entwickelte integrierte Bündelblockausgleichung ermöglicht die Bestimmung der exakten 3D-Kamerageometrie sowie die Schätzung der distanzmessspezifischen Korrekturparameter zur Modellierung linearer, zyklischer und signalwegeffektbedingter Fehleranteile einer 3D-Kamerastreckenmessung. Die integrierte Kalibrierroutine gleicht in beiden Informationskanälen gemessene Größen gemeinsam, unter der automatischen Schätzung optimaler Beobachtungsgewichte, aus. Die Methode basiert auf dem flexiblen Prinzip einer Selbstkalibrierung und benötigt keine Objektrauminformation, wodurch insbesondere die aufwendige Ermittlung von Referenzstrecken übergeordneter Genauigkeit entfällt. Die durchgeführten Genauigkeitsuntersuchungen bestätigen die Richtigkeit der aufgestellten funktionalen Zusammenhänge, zeigen aber auch Schwächen aufgrund noch nicht parametrisierter distanzmessspezifischer Fehler. Die Adaptivität und die modulare Implementierung des entwickelten mathematischen Modells gewährleisten aber eine zukünftige Erweiterung. Die Qualität der 3D-Neupunktkoordinaten kann nach einer Kalibrierung mit 5 mm angegeben werden. Für die durch eine Vielzahl von meist simultan auftretenden Rauschquellen beeinflusste Tiefenbildtechnologie ist diese Genauigkeitsangabe sehr vielversprechend, vor allem im Hinblick auf die Entwicklung von auf korrigierten 3D-Kameradaten aufbauenden Auswertealgorithmen. 2,5D Least Squares Tracking (LST) ist eine im Rahmen der Dissertation entwickelte integrierte spatiale und temporale Zuordnungsmethode zur Auswertung von 3D-Kamerabildsequenzen. Der Algorithmus basiert auf der in der Photogrammetrie bekannten Bildzuordnung nach der Methode der kleinsten Quadrate und bildet kleine Oberflächensegmente konsekutiver 3D-Kameradatensätze aufeinander ab. Die Abbildungsvorschrift wurde, aufbauend auf einer 2D-Affintransformation, an die Datenstruktur einer 3D-Kamera angepasst. Die geschlossen formulierte Parametrisierung verknüpft sowohl Grau- als auch Entfernungswerte in einem integrierten Modell. Neben den affinen Parametern zur Erfassung von Translations- und Rotationseffekten, modellieren die Maßstabs- sowie Neigungsparameter perspektivbedingte Größenänderungen des Bildausschnitts, verursacht durch Distanzänderungen in Aufnahmerichtung. Die Eingabedaten sind in einem Vorverarbeitungsschritt mit Hilfe der entwickelten Kalibrierroutine um ihre opto- und distanzmessspezifischen Fehler korrigiert sowie die gemessenen Schrägstrecken auf Horizontaldistanzen reduziert worden. 2,5D-LST liefert als integrierter Ansatz vollständige 3D-Verschiebungsvektoren. Weiterhin können die aus der Fehlerrechnung resultierenden Genauigkeits- und Zuverlässigkeitsangaben als Entscheidungskriterien für die Integration in einer anwendungsspezifischen Verarbeitungskette Verwendung finden. Die Validierung des Verfahrens zeigte, dass die Einführung komplementärer Informationen eine genauere und zuverlässigere Lösung des Korrespondenzproblems bringt, vor allem bei schwierigen Kontrastverhältnissen in einem Kanal. Die Genauigkeit der direkt mit den Distanzkorrekturtermen verknüpften Maßstabs- und Neigungsparameter verbesserte sich deutlich. Darüber hinaus brachte die Erweiterung des geometrischen Modells insbesondere bei der Zuordnung natürlicher, nicht gänzlich ebener Oberflächensegmente signifikante Vorteile. Die entwickelte flächenbasierte Methode zur Objektzuordnung und Objektverfolgung arbeitet auf der Grundlage berührungslos aufgenommener 3D-Kameradaten. Sie ist somit besonders für Aufgabenstellungen der 3D-Bewegungsanalyse geeignet, die den Mehraufwand einer multiokularen Experimentalanordnung und die Notwendigkeit einer Objektsignalisierung mit Zielmarken vermeiden möchten. Das Potential des 3D-Kamerazuordnungsansatzes wurde an zwei Anwendungsszenarien der menschlichen Verhaltensforschung demonstriert. 2,5D-LST kam zur Bestimmung der interpersonalen Distanz und Körperorientierung im erziehungswissenschaftlichen Untersuchungsgebiet der Konfliktregulation befreundeter Kindespaare ebenso zum Einsatz wie zur Markierung und anschließenden Klassifizierung von Bewegungseinheiten sprachbegleitender Handgesten. Die Implementierung von 2,5D-LST in die vorgeschlagenen Verfahren ermöglichte eine automatische, effektive, objektive sowie zeitlich und räumlich hochaufgelöste Erhebung und Auswertung verhaltensrelevanter Daten. Die vorliegende Dissertation schlägt die Verwendung einer neuartigen 3D-Tiefenbildkamera zur Erhebung menschlicher Verhaltensdaten vor. Sie präsentiert sowohl ein zur Datenaufbereitung entwickeltes Kalibrierwerkzeug als auch eine Methode zur berührungslosen Bestimmung dichter 3D-Bewegungsvektorfelder. Die Arbeit zeigt, dass die Methoden der Photogrammetrie auch für bewegungsanalytische Aufgabenstellungen auf dem bisher noch wenig erschlossenen Gebiet der Verhaltensforschung wertvolle Ergebnisse liefern können. Damit leistet sie einen Beitrag für die derzeitigen Bestrebungen in der automatisierten videographischen Erhebung von Körperbewegungen in dyadischen Interaktionen. / The three-dimensional documentation of the form and location of any type of object using flexible photogrammetric methods and procedures plays a key role in a wide range of technical-industrial and scientific areas of application. Potential applications include measurement tasks in the automotive, machine building and ship building sectors, the compilation of complex 3D models in the fields of architecture, archaeology and monumental preservation and motion analyses in the fields of flow measurement technology, ballistics and medicine. In the case of close-range photogrammetry a variety of optical 3D measurement systems are used. Area sensor cameras arranged in single or multi-image configurations are used besides active triangulation procedures for surface measurement (e.g. using structured light or laser scanner systems). The use of modulation techniques enables 3D cameras based on photomix detectors or similar principles to simultaneously produce both a grey value image and a range image. Functioning as single image sensors, they deliver spatially resolved surface data at video rate without the need for stereoscopic image matching. In the case of 3D motion analyses in particular, this leads to considerable reductions in complexity and computing time. 3D cameras combine the practicality of a digital camera with the 3D data acquisition potential of conventional surface measurement systems. Despite the relatively low spatial resolution currently achievable, as a monosensory real-time depth image acquisition system they represent an interesting alternative in the field of 3D motion analysis. The use of 3D cameras as measuring instruments requires the modelling of deviations from the ideal projection model, and indeed the processing of the 3D camera data generated requires the targeted adaptation, development and further development of procedures in the fields of computer graphics and photogrammetry. This Ph.D. thesis therefore focuses on the development of methods of sensor calibration and 3D motion analysis in the context of investigations into inter-human motion behaviour. As a result of its intrinsic design and measurement principle, a 3D camera simultaneously provides amplitude and range data reconstructed from a measurement signal. The simultaneous integration of all data obtained using a 3D camera into an integrated approach is a logical consequence and represents the focus of current procedural development. On the one hand, the complementary characteristics of the observations made support each other due to the creation of a functional context for the measurement channels, with is to be expected to lead to increases in accuracy and reliability. On the other, the expansion of the stochastic model to include variance component estimation ensures that the heterogeneous information pool is fully exploited. The integrated bundle adjustment developed facilitates the definition of precise 3D camera geometry and the estimation of range-measurement-specific correction parameters required for the modelling of the linear, cyclical and latency defectives of a distance measurement made using a 3D camera. The integrated calibration routine jointly adjusts appropriate dimensions across both information channels, and also automatically estimates optimum observation weights. The method is based on the same flexible principle used in self-calibration, does not require spatial object data and therefore foregoes the time-consuming determination of reference distances with superior accuracy. The accuracy analyses carried out confirm the correctness of the proposed functional contexts, but nevertheless exhibit weaknesses in the form of non-parameterized range-measurement-specific errors. This notwithstanding, the future expansion of the mathematical model developed is guaranteed due to its adaptivity and modular implementation. The accuracy of a new 3D point coordinate can be set at 5 mm further to calibration. In the case of depth imaging technology – which is influenced by a range of usually simultaneously occurring noise sources – this level of accuracy is very promising, especially in terms of the development of evaluation algorithms based on corrected 3D camera data. 2.5D Least Squares Tracking (LST) is an integrated spatial and temporal matching method developed within the framework of this Ph.D. thesis for the purpose of evaluating 3D camera image sequences. The algorithm is based on the least squares image matching method already established in photogrammetry, and maps small surface segments of consecutive 3D camera data sets on top of one another. The mapping rule has been adapted to the data structure of a 3D camera on the basis of a 2D affine transformation. The closed parameterization combines both grey values and range values in an integrated model. In addition to the affine parameters used to include translation and rotation effects, the scale and inclination parameters model perspective-related deviations caused by distance changes in the line of sight. A pre-processing phase sees the calibration routine developed used to correct optical and distance-related measurement specific errors in input data and measured slope distances reduced to horizontal distances. 2.5D LST is an integrated approach, and therefore delivers fully three-dimensional displacement vectors. In addition, the accuracy and reliability data generated by error calculation can be used as decision criteria for integration into an application-specific processing chain. Process validation showed that the integration of complementary data leads to a more accurate, reliable solution to the correspondence problem, especially in the case of difficult contrast ratios within a channel. The accuracy of scale and inclination parameters directly linked to distance correction terms improved dramatically. In addition, the expansion of the geometric model led to significant benefits, and in particular for the matching of natural, not entirely planar surface segments. The area-based object matching and object tracking method developed functions on the basis of 3D camera data gathered without object contact. It is therefore particularly suited to 3D motion analysis tasks in which the extra effort involved in multi-ocular experimental settings and the necessity of object signalling using target marks are to be avoided. The potential of the 3D camera matching approach has been demonstrated in two application scenarios in the field of research into human behaviour. As in the case of the use of 2.5D LST to mark and then classify hand gestures accompanying verbal communication, the implementation of 2.5D LST in the proposed procedures for the determination of interpersonal distance and body orientation within the framework of pedagogical research into conflict regulation between pairs of child-age friends facilitates the automatic, effective, objective and high-resolution (from both a temporal and spatial perspective) acquisition and evaluation of data with relevance to behaviour. This Ph.D. thesis proposes the use of a novel 3D range imaging camera to gather data on human behaviour, and presents both a calibration tool developed for data processing purposes and a method for the contact-free determination of dense 3D motion vector fields. It therefore makes a contribution to current efforts in the field of the automated videographic documentation of bodily motion within the framework of dyadic interaction, and shows that photogrammetric methods can also deliver valuable results within the framework of motion evaluation tasks in the as-yet relatively untapped field of behavioural research.

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