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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.
111

Kalibrace robotického pracoviště / Calibration of Robotic Workspace

Uhlíř, Jan January 2019 (has links)
This work is concerned by the issue of calibrating a robotic workplace, including the localization of a calibration object for the purpose of calibrating a 2D or 3D camera, a robotic arm and a scene of robotic workplace. At first, the problems related to the calibration of the aforementioned elements were studied. Further, an analysis of suitable methods for performing these calibrations was performed. The result of this work is application of ROS robotic system providing methods for three different types of calibration programs, whose functionality is experimentally verified at the end of this work.
112

3D model vybraného objektu / 3D model of the selected object

Raclavský, David January 2020 (has links)
The result of the diploma thesis is a photogrammetrically evaluated georeferenced 3D model of an object with its environment, located in the AdMaS complex. The work describes in detail all phases of creating a 3D model of the object from the selection and calibration of the camera to editing the 3D model. Discuss about software and methods for evaluating 3D models. The thesis deals with the optimal setting of ContectCapture software. The accuracy of the resulting 3D model is tested by the methodology according to ČSN 013410 on the basis of control measurements.
113

Vizuální detekce elektronických součástek / Visual detection of electronic devices

Juhas, Miroslav January 2010 (has links)
This thesis describes application of image processing for precise distance measurement in self acting production of a tip for AFM microscopes. The main goal is to measure distances between assembly parts during fabrication process. The purpose is to acquire a data for self acting assembly line which have to substitute inaccurate and nonrecurring manual assembly process. The assembly process consists of three technological steps. In first two steps the tungsten wire is glued to the cantilever. Distance measurement is necessary in all axes for proper alignment of parts. In third step the sharp tip is etched by KOH solution. The right distance between liquid level and the cantilever must be kept. A camera with high resolution and macro objective is used to acquire an image. Camera image is then calibrated to suppress distortions and scene position with respect to camera position. Length conversion coefficient is also computed. Object recognition and distance measurement is based on standard computer vision methods, mainly: adaptive thresholding, moments, image statistics, canny edge detector, Hough transform… Proposed algorithms have been implemented in C++ using Intel OpenCV library. The final achieved distance resolution is about 10µm per pixel. Algorithm output was successfully used to assembly few test tips.
114

Měření výšky postavy v obraze / Height Measurement in Digital Image

Olejár, Adam January 2015 (has links)
The aim of this paper is a summary of the theory necessary for a modification, detection of person and the height calculation of the detected person in the image. These information were then used for implementation of the algoritm. The first half reveals teoretical problems and solutions. Shows the basic methods of image preprocessing and discusses the basic concepts of plane and projective geometry and transformations. Then describes the distortion, that brings into the picture imperfections of optical systems of cameras and the possibilities of removing them. Explains HOG algorithm and the actual method of calculating height of person detected in the image. The second half describes algoritm structure and statistical evaluation.
115

Dokumentace historických artefaktů s využitím blízké fotogrammetrie / Use of Close Range Photogrammetry for Documentation of Historical Artefacts.

Naništa, Jiří January 2013 (has links)
This diploma thesis deals with the design and implementation of appropriate procedure photogrammetry processing of technical documentation of selected historical artifacts gauges. During processing was calibrated camera, historical gauges were photographed and metrological documented and model viualization was created.
116

Určení pozice mobilního zařízení v prostoru / Localization of Mobile Device in Space

Komár, Michal January 2013 (has links)
This thesis focuses on the current localization options of the Android mobile phone platform. It explores the possibilities of locating mobile devices not only with the use of inertial sensors, but also the possibility of localization using integrated video camera. The work describes the measurements done with available inertial sensors, introduces visual localization algorithm and design a system using these two approaches.
117

Lokalizace objektů v prostoru / Object Localisation in 3D Space

Šolony, Marek Unknown Date (has links)
Virtual reality systems are nowadays common part of many research institutes due to its low cost and effective visualization of data. They mostly allow visualization and exploration of virtual worlds, but many lack user interaction. In this paper we suggest multi-camera optical system, which allows effective user interaction, thereby increasing immersion of virtual system. This paper describes the calibration process of multiple cameras using point correspondences.
118

Geometric model of a dual-fisheye system composed of hyper-hemispherical lenses /

Castanheiro, Letícia Ferrari January 2020 (has links)
Orientador: Antonio Maria Garcia Tommaselli / Resumo: A combinação de duas lentes com FOV hiper-hemisférico em posição opostas pode gerar um sistema omnidirecional (FOV 360°) leve, compacto e de baixo custo, como Ricoh Theta S e GoPro Fusion. Entretanto, apenas algumas técnicas e modelos matemáticos para a calibração um sistema com duas lentes hiper-hemisféricas são apresentadas na literatura. Nesta pesquisa, é avaliado e definido um modelo geométrico para calibração de sistemas omnidirecionais compostos por duas lentes hiper-hemisféricas e apresenta-se algumas aplicações com esse tipo de sistema. A calibração das câmaras foi realizada no programa CMC (calibração de múltiplas câmeras) utilizando imagens obtidas a partir de vídeos feitos com a câmara Ricoh Theta S no campo de calibração 360°. A câmara Ricoh Theta S é composto por duas lentes hiper-hemisféricas fisheye que cobrem 190° cada uma. Com o objetivo de avaliar as melhorias na utilização de pontos em comum entre as imagens, dois conjuntos de dados de pontos foram considerados: (1) apenas pontos no campo hemisférico, e (2) pontos em todo o campo de imagem (isto é, adicionar pontos no campo de imagem hiper-hemisférica). Primeiramente, os modelos ângulo equisólido, equidistante, estereográfico e ortogonal combinados com o modelo de distorção Conrady-Brown foram testados para a calibração de um sensor da câmara Ricoh Theta S. Os modelos de ângulo-equisólido e estereográfico apresentaram resultados melhores do que os outros modelos. Portanto, esses dois modelos de projeção for... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The arrangement of two hyper-hemispherical fisheye lenses in opposite position can design a light weight, small and low-cost omnidirectional system (360° FOV), e.g. Ricoh Theta S and GoPro Fusion. However, only a few techniques are presented in the literature to calibrate a dual-fisheye system. In this research, a geometric model for dual-fisheye system calibration was evaluated, and some applications with this type of system are presented. The calibrating bundle adjustment was performed in CMC (calibration of multiple cameras) software by using the Ricoh Theta video frames of the 360° calibration field. The Ricoh Theta S system is composed of two hyper-hemispherical fisheye lenses with 190° FOV each one. In order to evaluate the improvement in applying points in the hyper-hemispherical image field, two data set of points were considered: (1) observations that are only in the hemispherical field, and (2) points in all image field, i.e. adding points in the hyper-hemispherical image field. First, one sensor of the Ricoh Theta S system was calibrated in a bundle adjustment based on the equidistant, equisolid-angle, stereographic and orthogonal models combined with Conrady-Brown distortion model. Results showed that the equisolid-angle and stereographic models can provide better solutions than those of the others projection models. Therefore, these two projection models were implemented in a simultaneous camera calibration, in which the both Ricoh Theta sensors were considered i... (Complete abstract click electronic access below) / Mestre
119

Calibrage de caméra fisheye et estimation de la profondeur pour la navigation autonome

Brousseau, Pierre-André 08 1900 (has links)
Ce mémoire s’intéresse aux problématiques du calibrage de caméras grand angles et de l’estimation de la profondeur à partir d’une caméra unique, immobile ou en mouvement. Les travaux effectués se situent à l’intersection entre la vision 3D classique et les nouvelles méthodes par apprentissage profond dans le domaine de la navigation autonome. Ils visent à permettre la détection d’obstacles par un drone en mouvement muni d’une seule caméra à très grand angle de vue. D’abord, une nouvelle méthode de calibrage est proposée pour les caméras fisheyes à très grand angle de vue par calibrage planaire à correspondances denses obtenues par lumière structurée qui peuvent être modélisée par un ensemble de caméras génériques virtuelles centrales. Nous démontrons que cette approche permet de modéliser directement des caméras axiales, et validons sur des données synthétiques et réelles. Ensuite, une méthode est proposée pour estimer la profondeur à partir d’une seule image, à partir uniquement des indices de profondeurs forts, les jonctions en T. Nous démontrons que les méthodes par apprentissage profond sont susceptibles d’apprendre les biais de leurs ensembles de données et présentent des lacunes d’invariance. Finalement, nous proposons une méthode pour estimer la profondeur à partir d’une caméra en mouvement libre à 6 degrés de liberté. Ceci passe par le calibrage de la caméra fisheye sur le drone, l’odométrie visuelle et la résolution de la profondeur. Les méthodes proposées permettent la détection d’obstacle pour un drone. / This thesis focuses on the problems of calibrating wide-angle cameras and estimating depth from a single camera, stationary or in motion. The work carried out is at the intersection between traditional 3D vision and new deep learning methods in the field of autonomous navigation. They are designed to allow the detection of obstacles by a moving drone equipped with a single camera with a very wide field of view. First, a new calibration method is proposed for fisheye cameras with very large field of view by planar calibration with dense correspondences obtained by structured light that can be modelled by a set of central virtual generic cameras. We demonstrate that this approach allows direct modeling of axial cameras, and validate it on synthetic and real data. Then, a method is proposed to estimate the depth from a single image, using only the strong depth cues, the T-junctions. We demonstrate that deep learning methods are likely to learn from the biases of their data sets and have weaknesses to invariance. Finally, we propose a method to estimate the depth from a camera in free 6 DoF motion. This involves calibrating the fisheye camera on the drone, visual odometry and depth resolution. The proposed methods allow the detection of obstacles for a drone.
120

Rekonstrukce 3D objektu z obrazových dat / 3D Objects Reconstruction from Image Data

Cír, Filip January 2008 (has links)
This paper deals with 3D reconstruction of objects from image data. There is describes theoretical basis of the 3D optical scanning. Handheld 3D optical scanner setup is described composed of a single camera and a line laser whose position is fixed with respect to the camera. Set of image markers and a simple real-time detection algorithm are proposed. Detected markers are used to estimate position and orientation of the camera. Finally, laser detection and triangulation of points lying on object surface are discussed.

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