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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.
271

Aplikace rozšířené reality: Měření rozměrů objektů / Application of Augmented Reality: Measurement of Object Dimensions

Karásek, Miroslav January 2019 (has links)
The goal of this diploma thesis is design and implementation of an application for automated measurement of objects in augmented reality. It focuses on automating the entire process, so that the user carries out the fewest number of manual actions. The proposed interface divides the measurement into several steps in which it gives the user instructions to progress to the next stage. The result is an Android application with ARCore technology. Is capable of determining the minimal bounding box of an object of a general shape lying on a horizontal surface. Measure error depends on ambient conditions and is in units of percent.
272

Automatická kalibrace robotického ramene pomocí kamer/y / Automatic calibration ot robotic arm using cameras

Adámek, Daniel January 2019 (has links)
K nahrazení člověka při úloze testování dotykových embedded zařízení je zapotřebí vyvinout komplexní automatizovaný robotický systém. Jedním ze zásadních úkolů je tento systém automaticky zkalibrovat. V této práci jsem se zabýval možnými způsoby automatické kalibrace robotického ramene v prostoru ve vztahu k dotykovému zařízení pomocí jedné či více kamer. Následně jsem představil řešení založené na estimaci polohy jedné kamery pomocí iterativních metod jako např. Gauss-Newton nebo Levenberg-Marquardt. Na konci jsem zhodnotil dosaženou přesnost a navrhnul postup pro její zvýšení.
273

6-DOF lokalizace objektů v průmyslových aplikacích / 6-DOF Object Localization in Industrial Applications

Macurová, Nela January 2021 (has links)
The aim of this work is to design a method for the object localization in the point could and as accurately as possible estimates the 6D pose of known objects in the industrial scene for bin picking. The design of the solution is inspired by the PoseCNN network. The solution also includes a scene simulator that generates artificial data. The simulator is used to generate a training data set containing 2 objects for training a convolutional neural network. The network is tested on annotated real scenes and achieves low success, only 23.8 % and 31.6 % success for estimating translation and rotation for one type of obejct and for another 12.4 % and 21.6 %, while the tolerance for correct estimation is 5 mm and 15°. However, by using the ICP algorithm on the estimated results, the success of the translation estimate is 81.5 % and the rotation is 51.8 % and for the second object 51.9 % and 48.7 %. The benefit of this work is the creation of a generator and testing the functionality of the network on small objects
274

Automated Gait Analysis : Using Deep Metric Learning

Engström, Isak January 2021 (has links)
Sectors of security, safety, and defence require methods for identifying people on the individual level. Automation of these tasks has the potential of outperforming manual labor, as well as relieving workloads. The ever-extending surveillance camera networks, advances in human pose estimation from monocular cameras, together with the progress of deep learning techniques, pave the way for automated walking gait analysis as an identification method. This thesis investigates the use of 2D kinematic pose sequences to represent gait, monocularly extracted from a limited dataset containing walking individuals captured from five camera views. The sequential information of the gait is captured using recurrent neural networks. Techniques in deep metric learning are applied to evaluate two network models, with contrasting output dimensionalities, against deep-metric-, and non-deep-metric-based embedding spaces. The results indicate that the gait representation, network designs, and network learning structure show promise when identifying individuals, scaling particularly well to unseen individuals. However, with the limited dataset, the network models performed best when the dataset included the labels from both the individuals and the camera views simultaneously, contrary to when the data only contained the labels from the individuals without the information of the camera views. For further investigations, an extension of the data would be required to evaluate the accuracy and effectiveness of these methods, for the re-identification task of each individual. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>
275

Simutaneous real-time object recognition and pose estimation for artificial systems operating in dynamic environments

Van Wyk, Frans-Pieter January 2013 (has links)
Recent advances in technology have increased awareness of the necessity for automated systems in people’s everyday lives. Artificial systems are more frequently being introduced into environments previously thought to be too perilous for humans to operate in. Some robots can be used to extract potentially hazardous materials from sites inaccessible to humans, while others are being developed to aid humans with laborious tasks. A crucial aspect of all artificial systems is the manner in which they interact with their immediate surroundings. Developing such a deceivingly simply aspect has proven to be significantly challenging, as it not only entails the methods through which the system perceives its environment, but also its ability to perform critical tasks. These undertakings often involve the coordination of numerous subsystems, each performing its own complex duty. To complicate matters further, it is nowadays becoming increasingly important for these artificial systems to be able to perform their tasks in real-time. The task of object recognition is typically described as the process of retrieving the object in a database that is most similar to an unknown, or query, object. Pose estimation, on the other hand, involves estimating the position and orientation of an object in three-dimensional space, as seen from an observer’s viewpoint. These two tasks are regarded as vital to many computer vision techniques and regularly serve as input to more complex perception algorithms. An approach is presented which regards the object recognition and pose estimation procedures as mutually dependent. The core idea is that dissimilar objects might appear similar when observed from certain viewpoints. A feature-based conceptualisation, which makes use of a database, is implemented and used to perform simultaneous object recognition and pose estimation. The design incorporates data compression techniques, originally suggested by the image-processing community, to facilitate fast processing of large databases. System performance is quantified primarily on object recognition, pose estimation and execution time characteristics. These aspects are investigated under ideal conditions by exploiting three-dimensional models of relevant objects. The performance of the system is also analysed for practical scenarios by acquiring input data from a structured light implementation, which resembles that obtained from many commercial range scanners. Practical experiments indicate that the system was capable of performing simultaneous object recognition and pose estimation in approximately 230 ms once a novel object has been sensed. An average object recognition accuracy of approximately 73% was achieved. The pose estimation results were reasonable but prompted further research. The results are comparable to what has been achieved using other suggested approaches such as Viewpoint Feature Histograms and Spin Images. / Dissertation (MEng)--University of Pretoria, 2013. / gm2014 / Electrical, Electronic and Computer Engineering / unrestricted
276

Towards Color-Based Two-Hand 3D Global Pose Estimation

Lin, Fanqing 14 June 2022 (has links)
Pose estimation and tracking is essential for applications involving human controls. Specifically, as the primary operating tool for human activities, hand pose estimation plays a significant role in applications such as hand tracking, gesture recognition, human-computer interaction and VR/AR. As the field develops, there has been a trend to utilize deep learning to estimate the 2D/3D hand poses using color-based information without depth data. Within the depth-based as well as color-based approaches, the research community has primarily focused on single-hand scenarios in a localized/normalized coordinate system. Due to the fact that both hands are utilized in most applications, we propose to push the frontier by addressing two-hand pose estimation in the global coordinate system using only color information. Our first chapter introduces the first system capable of estimating global 3D joint locations for both hands via only monocular RGB input images. To enable training and evaluation of the learning-based models, we propose to introduce a large-scale synthetic 3D hand pose dataset Ego3DHands. As knowledge in synthetic data cannot be directly applied to the real-world domain, a natural two-hand pose dataset is necessary for real-world applications. To this end, we present a large-scale RGB-based egocentric hand dataset Ego2Hands in two chapters. In chapter 2, we address the task of two-hand segmentation/detection using images in the wild. In chapter 3, we focus on the task of two-hand 2D/3D pose estimation using real-world data. In addition to research in hand pose estimation, chapter 4 includes our work on interactive refinement that generalizes the backpropagating refinement technique for dense prediction models.
277

Human pose estimation in low-resolution images / Estimering av mänskliga poser i lågupplösta bilder

Nilsson, Hugo January 2022 (has links)
This project explores the understudied, yet important, case of human pose estimation in low-resolution images. This is done in the use-case of images with football players of known scale in the image. Human pose estimation can mainly be done in two different ways, the bottom-up method and the top-down method. This project explores the bottom-up method, which first finds body keypoints and then groups them to get the person, or persons, within the image. This method is generally faster and has been shown to have an advantage when there is occlusion or crowded scenes, but suffers from false positive errors. Low-resolution makes human pose estimation harder, due to the decreased information that can be extracted. Furthermore, the output heatmap risks becoming too small to correctly locate the keypoints. However, low-resolution human pose estimation is needed in many cases, if the camera has a low-resolution sensor or the person occupies a small portion of the image. Several neural networks are evaluated and, in conclusion, there are multiple ways to improve the current state of the art network HigherHRNet for lower resolution human pose estimation. Maintaining large feature maps through the network turns out to be crucial for low-resolution images and can be achieved by modifying the feature extractor in HigherHRNet. Furthermore, as the resolution decreases, the need for sub-pixel accuracy grows. To improve this, various heatmap encoding-decoding methods are investigated, and by using unbiased data processing, both heatmap encoding-decoding and coordinate system transformation can be improved. / Detta projekt utforskar det understuderade, men ändå viktiga, fallet med uppskattning av mänskliga poser i lågupplösta bilder. Detta görs i användningsområdet av bilder med fotbollsspelare av en förutbestämd storlek i bilden. Mänskliga poseuppskattningar kan huvudsakligen göras på två olika sätt, nedifrån-och-upp- metoden och uppifrån-och-ned-metoden. Detta projekt utforskar nedifrån-och- upp-metoden, som först hittar kroppsdelar och sedan grupperar dem för att få fram personen, eller personerna, i bilden. Denna metod är generellt sett snabbare och har visat sig vara fördelaktig i scenarion med ocklusion eller mycket folk, men lider av falska positiva felaktigheter. Låg upplösning gör uppskattning av mänskliga poser svårare, på grund av den minskade informationen som kan extraheras. Dessutom riskerar färgdiagramet att bli för liten för att korrekt lokalisera kroppsdelarna. Ändå behövs uppskattning av lågupplöst mänskliga poser i många fall, exempelvis om kameran har en lågupplöst sensor eller om personen upptar en liten del av bilden. Flera neurala nätverk utvärderas och sammanfattningsvis finns flera sätt att förbättra det nuvarande toppklassade nätverket HigherHRNet för uppskattning av mänskliga poser med lägre upplösning. Att bibehålla stora särdragskartor genom nätverket visar sig vara avgörande för lågupplösta bilder och kan uppnås genom att modifiera särdragsextraktorn i HigherHRNet. Dessutom, när upplösningen minskar, ökar behovet av subpixel-noggrannhet. För att förbättra detta undersöktes olika färgdiagram-kodning-avkodningsmetoder, och genom att använda opartisk databehandling kan både färgdiagram-kodning-avkodning och koordinatsystemtransformationen förbättras.
278

An Autonomous Intelligent Robotic Wheelchair to Assist People in Need: Standing-up, Turning-around and Sitting-down

Papadakis Ktistakis, Iosif January 2018 (has links)
No description available.
279

Robust Localization of Research Concept Vehicle (RCV) in Large Scale Environment / Robust lokalisering av Research Concept Vehicle (RCV) i storskalig miljö

Raghuram, Anchit January 2018 (has links)
Autonomous vehicles in the recent era are robust vehicles that have the capability to drive themselves without human involvement using sensors and Simultaneous Localization and Mapping algorithms, which helps the vehicle gain an understanding of its environment while driving with the help of laser scanners (Velodyne), IMU and GPS to collect data and solidify the foundation for locating itself in an unknown environment. Various methods were studied and have been tested for increasing the efficiency of registration and optimization over the years but the implementation of the NDT library for mapping and localization have been found to be fast and more accurate as compared to conventional methods. The objective of this thesis is to ascertain a robust method of pose estimation of the vehicle by combining data from the laser sensor, with the data from the IMU and GPS receiver on the vehicle. The initial estimate prediction of the position is achieved by generating a 3D map using the Normal Distribution Transform and estimating the position using the NDT localization algorithm and the GPS data collected by driving the vehicle in an external environment. The results presented explain and verify the hypothesis being stated and shows the comparison of the localization algorithm implemented with the GPS receiver data available on the vehicle while driving. / Autonoma fordon har på senare tid utvecklats till robusta fordon som kan köra sig själva utan hjälp av en människa, detta har möjliggjorts genom användandet av sensorer och algoritmer som utför lokalisering och kartläggning samtidigt (SLAM). Dessa sensorer och algoritmer hjälper fordonet att förstå dess omgivning medan det kör och tillsammans med laser skanners (Velodyne), IMU'er och GPS läggs grunden för att kunna utföra lokalisering i en okänd miljö. Ett flertal metoder har studerats och testats för att förbättra effektiviteten av registrering och optimering under åren men implementationen av NDT biblioteket för kartläggning och lokalisering har visat sig att vara snabbt och mer exakt jämfört med konventionella metoder. Målet med detta examensarbete är att hitta en robust metod för uppskatta pose genom att kombinera data från laser sensorn, en uppskattning av den ursprungliga positionen som fås genom att generera en 3D karta med hjälp av normalfördelningstransformen och GPS data insamlad från körningar i en extern miljö. Resultaten som presenteras beskriver och verifierar den hypotes som läggs fram och visar jämförelsen av den implementerade lokaliseringsalgoritmen med GPS data tillgänglig på fordonet under körning.
280

Unsupervised 3D Human Pose Estimation / Oövervakad mänsklig poseuppskattning i 3D

Budaraju, Sri Datta January 2021 (has links)
The thesis proposes an unsupervised representation learning method to predict 3D human pose from a 2D skeleton via a VAEGAN (Variational Autoencoder Generative Adversarial Network) hybrid network. The method learns to lift poses from 2D to 3D using selfsupervision and adversarial learning techniques. The method does not use images, heatmaps, 3D pose annotations, paired/unpaired 2Dto3D skeletons, 3D priors, synthetic 2D skeletons, multiview or temporal information in any shape or form. The 2D skeleton input is taken by a VAE that encodes it in a latent space and then decodes that latent representation to a 3D pose. The 3D pose is then reprojected to 2D for a constrained, selfsupervised optimization using the input 2D pose. Parallelly, the 3D pose is also randomly rotated and reprojected to 2D to generate a ’novel’ 2D view for unconstrained adversarial optimization using a discriminator network. The combination of the optimizations of the original and the novel 2D views of the predicted 3D pose results in a ’realistic’ 3D pose generation. The thesis shows that the encoding and decoding process of the VAE addresses the major challenge of erroneous and incomplete skeletons from 2D detection networks as inputs and that the variance of the VAE can be altered to get various plausible 3D poses for a given 2D input. Additionally, the latent representation could be used for crossmodal training and many downstream applications. The results on Human3.6M datasets outperform previous unsupervised approaches with less model complexity while addressing more hurdles in scaling the task to the real world. / Uppsatsen föreslår en oövervakad metod för representationslärande för att förutsäga en 3Dpose från ett 2D skelett med hjälp av ett VAE GAN (Variationellt Autoenkodande Generativt Adversariellt Nätverk) hybrid neuralt nätverk. Metoden lär sig att utvidga poser från 2D till 3D genom att använda självövervakning och adversariella inlärningstekniker. Metoden använder sig vare sig av bilder, värmekartor, 3D poseannotationer, parade/oparade 2D till 3D skelett, a priori information i 3D, syntetiska 2Dskelett, flera vyer, eller tidsinformation. 2Dskelettindata tas från ett VAE som kodar det i en latent rymd och sedan avkodar den latenta representationen till en 3Dpose. 3D posen är sedan återprojicerad till 2D för att genomgå begränsad, självövervakad optimering med hjälp av den tvådimensionella posen. Parallellt roteras dessutom 3Dposen slumpmässigt och återprojiceras till 2D för att generera en ny 2D vy för obegränsad adversariell optimering med hjälp av ett diskriminatornätverk. Kombinationen av optimeringarna av den ursprungliga och den nya 2Dvyn av den förutsagda 3Dposen resulterar i en realistisk 3Dposegenerering. Resultaten i uppsatsen visar att kodningsoch avkodningsprocessen av VAE adresserar utmaningen med felaktiga och ofullständiga skelett från 2D detekteringsnätverk som indata och att variansen av VAE kan modifieras för att få flera troliga 3D poser för givna 2D indata. Dessutom kan den latenta representationen användas för crossmodal träning och flera nedströmsapplikationer. Resultaten på datamängder från Human3.6M är bättre än tidigare oövervakade metoder med mindre modellkomplexitet samtidigt som de adresserar flera hinder för att skala upp uppgiften till verkliga tillämpningar.

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