Sistema de digitalização 3D usando super-resolução em imagens RGBD

Orientador : Prof. Dr. Luciano SilvaCo-orientadora : Profª. Drª. Olga R. P. BellonDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Exatas, Programa de Pós-Graduação em Informática. Defesa: Curitiba, 10/09/2013Inclui referênciasResumo: Com o advento de novos sensores de profundidade de baixo custo e com o aumento do poder de processamento paralelo das placas gr_a_cas, houve um aumento signi_cativo em pesquisas na _area de reconstru_c~ao 3D em tempo real. No grupo de pesquisa IMAGO, existe um sistema de reconstru_c~ao 3D para a preserva _c~ao digital, adaptado aos scanners a laser de alta resolu_c~ao. Visando aumentar a exibilidade deste sistema, o objetivo deste trabalho _e a amplia_c~ao do atual pipeline de reconstru_c~ao 3D do IMAGO para permitir a cria_c~ao de modelos utilizando os novos sensores em tempo real. Outro objetivo _e a aplica_c~ao de um m_etodo para o tratamento das imagens de baixa qualidade desses sensores, proporcionando modelos reconstru__dos a partir das novas imagens de melhor resolu_c~ao. A principal meta da preserva_c~ao digital _e a _delidade tanto na geometria quanto na textura do modelo _nal, o tempo e custo computacional s~ao objetivos secund_arios. Portanto, o novo pipeline se resume a tr^es etapas: a modelagem geom_etrica em tempo real, a super-resolu_c~ao e a reconstru_c~ao 3D de alto custo. O objetivo da primeira _e proporcionar a captura completa e o armazenamento de todas as imagens, ambos em tempo real, usando o modelo atualizado apenas para guiar o usu_ario. Na segunda etapa, aumentamos a qualidade e resolu_c~ao das imagens capturadas para a cria_c~ao de um modelo mais _dedigno na etapa _nal, a etapa de reconstru_c~ao 3D utilizando o atual sistema do IMAGO.Abstract: With the advent of new low-cost depth sensors and with the increasing parallel processing power of graphics cards, there was a signi_cant increase in research involving the _eld of real-time 3D reconstruction. In the IMAGO research group, there is a 3D reconstruction system for digital preservation, applied to high resolution laser scanners. To increase the exibility of the mentioned system, our goal is to contributes to the expansion of IMAGO's current 3D reconstruction pipeline to enable the creation of models using new real-time depth sensors. Another objective is the employment of a method that process the sensor's low resolution images, providing reconstructed models using higher resolution images. The aim of digital preservation is the accuracy in both geometry and texture for the _nal model, the computational time and cost are secondary goals. Therefore, the new pipeline is summarized in three steps: a real-time geometric modeling, a super-resolution technique, and high-cost geometric modeling. The goal of the _rst step is to provide a complete capture and image storage, using the real-time model to guide the user. In the second step, we increase the quality and resolution of the captured images to create smooth and accurate models in the 3D reconstruction step using IMAGO's current system

Coordinated Landing and Mapping with Aerial and Ground Vehicle Teams

Micro Umanned Aerial Vehicle~(UAV) and Umanned Ground Vehicle~(UGV) teams present tremendous opportunities in expanding the range of operations for these vehicles. An effective coordination of these vehicles can take advantage of the strengths of both, while mediate each other's weaknesses. In particular, a micro UAV typically has limited flight time due to its weak payload capacity. To take advantage of the mobility and sensor coverage of a micro UAV in long range, long duration surveillance mission, a UGV can act as a mobile station for recharging or battery swap, and the ability to perform autonomous docking is a prerequisite for such operations. This work presents an approach to coordinate an autonomous docking between a quadrotor UAV and a skid-steered UGV. A joint controller is designed to eliminate the relative position error between the vehicles. The controller is validated in simulations and successful landing is achieved in indoor environment, as well as outdoor settings with standard sensors and real disturbances. Another goal for this work is to improve the autonomy of UAV-UGV teams in positioning denied environments, a very common scenarios for many robotics applications. In such environments, Simultaneous Mapping and Localization~(SLAM) capability is the foundation for all autonomous operations. A successful SLAM algorithm generates maps for path planning and object recognition, while providing localization information for position tracking. This work proposes an SLAM algorithm that is capable of generating high fidelity surface model of the surrounding, while accurately estimating the camera pose in real-time. This algorithm improves on a clear deficiency of its predecessor in its ability to perform dense reconstruction without strict volume limitation, enabling practical deployment of this algorithm on robotic systems

Vermessung, Modellierung und Verifizierung von Licht-Masse-Interaktions-Phänomenen

The photo-realistic rendering of scenes showing natural phenomena requires skilled graphic designers not only to produce a convincingly good-looking image but also to convey physical plausibility. This is especially important in industrial context, where a modelled scene showcasing a product has to approximate the actual environment of a product as closely as possible, e.g. in automotive industries. In this thesis, new techniques to measure natural phenomena are presented in order to provide new or verify existing models for rendering the physically plausible image. In contrast to other approaches, the measurement is performed using nonconventional methods: an ellipsometer is employed to capture the specular reflectance with respect to the polarisation behaviour, a transmissive screen attached to a glass tank is imaged to capture underwater reflectances, and the Microsoft Kinect, a motion capturing device, is used to detect the gas flows around objects. The results are the verification of existing, physically plausible models for commodity metals, an enhanced reflectance model for materials immersed in transparent media with known refractive index, and the reconstruction of two-phase gas flows around occluding objects.Das Erzeugen von Szenen mit natürlichen Phänomenen in fotorealistischer Qualität ist aufwändig, weil nicht nur ein realistisches Bild erstellt werden soll, sondern auch physikalische Plausibilität in Bezug auf das modellierte Phänomen verlangt wird. Besonders in der Industrie, z.B. in der Automobilindustrie, sollte die modellierte Szene, in der ein Produkt eingesetzt wird, der tatsächlichen Einsatzumgebung so naturgetreu wie möglich ähneln. In dieser Dissertation werden neue Ansätze zum Messen von natürlichen Phänomenen präsentiert, die es ermöglichen, für bestimmte Phänomene neue Modelle zu erstellen oder bestehende Modelle erschöpfender zu verifizieren, um damit physikalische Plausibilität für Szenen, die am Computer ereugt werden, zu gewährleisten. Im Unterschied zu anderen Verfahren, werden unkonventionelle Methoden zur Messung umgesetzt: Mit Hilfe eines Ellipsometers wird die Oberflächenreflektanz von Metallen so vermessen, dass auch Änderungen im Polarisationszustand des Lichtes erfasst werden. Unterwasserreflektanzen von Materialien werden mit Hilfe eines lichtdurchlässigen Diffusers abgebildet, der an einen Glasbecher angebracht wird, und der Bewegungssensor Kinect von Microsoft wird verwendet, um Gasströmungen um Objekte zu detektieren. Die Ergebnisse sind die Verifikation von bestehenden Modellen für handelsübliche Metallflächen, ein erweitertes Reflektanzmodell für Oberflächen, die in refraktive Medien eingetaucht werden und die Rekonstruktion von Gasströmungen um Objekte

Online Semantic Labeling of Deformable Tissues for Medical Applications

University of Minnesota Ph.D. dissertation. May 2017. Major: Mechanical Engineering. Advisor: Timothy Kowalewski. 1 computer file (PDF); ix, 133 pages.Surgery remains dangerous, and accurate knowledge of what is presented to the surgeon can be of great importance. One technique to automate this problem is non-rigid tracking of time-of-flight camera scans. This requires accurate sensors and prior information as well as an accurate non-rigid tracking algorithm. This thesis presents an evaluation of four algorithms for tracking and semantic labeling of deformable tissues for medical applications, as well as additional studies on a stretchable flexible smart skin and dynamic 3D bioprinting. The algorithms were developed and tested for this study, and were evaluated in terms of speed and accuracy. The algorithms tested were affine iterative closest point, nested iterative closest point, affine fast point feature histograms, and nested fast point feature histograms. The algorithms were tested against simulated data as well as direct scans. The nested iterative closest point algorithm provided the best balance of speed and accuracy while providing semantic labeling in both simulation as well as using directly scanned data. This shows that fast point feature histograms are not suitable for nonrigid tracking of geometric feature poor human tissues. Secondary experiments were also performed to show that the graphics processing unit provides enough speed to perform iterative closest point algorithms in real-time and that time of flight depth sensing works through an endoscope. Additional research was conducted on related topics, leading to the development of a novel stretchable flexible smart skin sensor and an active 3D bioprinting system for moving human anatomy