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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.
71

Multiple Hypothesis Testing Approach to Pedestrian Inertial Navigation with Non-recursive Bayesian Map-matching

Koroglu, Muhammed Taha 22 September 2020 (has links)
No description available.
72

Comparing Wrist Movement Analysis Technologies / Jämförelse av Tekniker för Analys av Handledsrörelser

Hanna, Markus, Cajander, Anton January 2023 (has links)
The wrist is a body part that can be used during repetitive movements in many work environments. There is a need to measure these movements in order to notice harmful repetitive movements in advance. There are many different ways to measure these movements, such as with the use of a depth camera. The goal of this study is to determine if this can be done with high precision compared to other technologies. In order to determine this, an application was created that used several different technologies and libraries to track and pinpoint the hand’s and forearm’s location in each frame. With these locations, together with timestamps from the frames, the angular velocity of the wrist could be calculated. The recordings were made in several different test cases with factors such as background, clothes and lighting changing in each test. In order to compare the depth cameras values, a golden standard had to be set. The depth camera’s recorded values were compared to the golden standard’s recorded values by displaying the values on a graph and by calculating the root mean squared error as well as the mean absolute error. The results indicated that a depth camera can be used to measure wrist movements relatively accurately, even with more advanced movements relative to this study. The result also showed that the depth camera had problems in some test cases. / Handleden är en kroppsdel som kan användas under repetitiva rörelser i många arbetsmiljöer. Det finns ett behov av att mäta dessa rörelser för att upptäcka skadliga repetitiva rörelser i förväg. Det finns många olika sätt att mäta dessa rörelser, till exempel med hjälp av en djupkamera. Målet med denna studie är att avgöra om detta kan göras med hög precision jämfört med andra teknologier. För att avgöra detta skapades en applikation som använder flera olika teknologier och bibliotek för att spåra och lokalisera handens och underarmens position i varje bildruta. Med hjälp av dessa positioner, tillsammans med tidsstämplar från bildrutorna, kunde vinkelhastigheten för handleden beräknas. Inspelningarna gjordes i flera olika testfall där faktorer som bakgrund, kläder och belysning ändrades i varje test. För att kunna jämföra djupkamerans värden behövdes en referensstandard fastställas. Djupkamerans inspelade värden jämfördes med referensstandardens inspelade värden genom att visa värdena på en graf och beräkna rotmedelkvadratfelet samt medelabsolutfelet. Resultaten indikerade att en djupkamera kan användas för att mäta handledsrörelser relativt noggrant, även med mer avancerade rörelser i förhållande till denna studie. Resultatet visade även att djupkameran hade problem i vissa testfall.
73

Domain Adaptation of IMU sensors using Generative Adversarial Networks

Radhakrishnan, Saieshwar January 2020 (has links)
Autonomous vehicles rely on sensors for a clear understanding of the environment and in a heavy duty truck, the sensors are placed at multiple locations like the cabin, chassis and the trailer in order to increase the field of view and reduce the blind spot area. Usually, these sensors perform best when they are stationary relative to the ground, hence large and fast movements, which are quite common in a truck, may lead to performance reduction, erroneous data or in the worst case, a sensor failure. This enforces a need to validate the sensors before using them for making life-critical decisions. This thesis proposes Domain Adaptation as one of the strategies to co-validate Inertial Measurement Unit (IMU) sensors. The proposed Generative Adversarial Network (GAN) based framework predicts the data of one IMU using other IMUs in the truck by implicitly learning the internal dynamics. This prediction model along with other sensor fusion strategies would be used by the supervising system to validate the IMUs in real-time. Through data collected from real-world experiments, it is shown that the proposed framework is able to accurately transform raw IMU sequences across domains. A further comparison is made between Long Short Term Memory (LSTM) and WaveNet based architectures to show the superiority of WaveNets in terms of performance and computational efficiency. / Autonoma fordon förlitar sig på sensorer för att skapa en bild av omgivningen. På en tung lastbil placeras sensorerna på multipla ställen, till exempel på hytten, chassiet och på trailern för att öka siktfältet och för att minska blinda områden. Vanligtvis presterar sensorerna som bäst när de är stationära i förhållande till marken, därför kan stora och snabba rörelser, som är vanliga på en lastbil, leda till nedsatt prestanda, felaktig data och i värsta fall fallerande sensorer. På grund av detta så finns det ett stort behov av att validera sensordata innan det används för kritiskt beslutsfattande. Den här avhandlingen föreslår domänadaption som en av de strategier för att samvalidera Tröghetsmätningssensorer (IMU-sensorer). Det föreslagna Generative Adversarial Network (GAN) baserade ramverket förutspår en Tröghetssensors data genom att implicit lära sig den interna dynamiken från andra Tröghetssensorer som är monterade på lastbilen. Den här prediktionsmodellen kombinerat med andra sensorfusionsstrategier kan användas av kontrollsystemet för att i realtid validera Tröghetssensorerna. Med hjälp av data insamlat från verkliga experiment visas det att det föreslagna ramverket klarar av att med hög noggrannhet konvertera obehandlade Tröghetssensor-sekvenser mellan domäner. Ytterligare en undersökning mellan Long Short Term Memory (LSTM) och WaveNet-baserade arkitekturer görs för att visa överlägsenheten i WaveNets när det gäller prestanda och beräkningseffektivitet.
74

Etude de la calibration et de l'intégration sur mini-drone d'un système caméra-capteurs inertiels et magnétiques et ses applications / Study of the calibration and the integration on a micro UAV of a camera-inertial and magnetic sensors system and its applications

Metge, Julien 16 December 2014 (has links)
Cette thèse aborde le problème de la calibration d’un ensemble de capteurscomposé d’une centrale inertielle, d’un magnétomètre et d’une caméra, avecpour objectif leur intégration sur un système très compact : un mini-drone.Cette étude expose tout d’abord les contraintes imposées par l’application surle choix des capteurs et les solutions envisagées notamment pour résoudre leproblème de la synchronisation des mesures. Après avoir étudié les techniquesde calibration existantes, une méthode permettant la calibration de l’ensembledes capteurs (accéléromètre, gyromètre, magnétomètre et caméra) est présentée.La solution proposée permet également d’estimer les changements de repèresentre les différents capteurs. Elle a la particularité de ne nécessiter l’emploid’aucun matériel particulier. D’autre part, l’intégration de ces capteurs dans unsystème aussi compact soulève de nouvelles difficultés. Dans ces conditions, leschamps magnétiques créés par les actionneurs du drone perturbent les mesuresdu magnétomètre se trouvant à proximité. Une nouvelle méthode est proposéeafin d’estimer et de compenser dynamiquement ces perturbations magnétiquesen fonction de l’état des actionneurs du drone. Enfin, deux applications dusystème comprenant une centrale inertielle et une caméra sont présentées :la construction de mosaïques d’images géo-référencées et la stabilisation devidéos. Ces deux applications exploitent les mesures des capteurs inertiels afind’effectuer un traitement en temps réel pour un coût calculatoire très faible. / This thesis deal with the issue of the calibration of a group of sensor composedof an inertial unit, a magnetometer and a camera. It aims at integratingthem into a very compact system : a mini-drone. First of all, this study outlinesthe constraints imposed by the application on the choice of the sensors andthe solutions considered to solve the measures synchronization issue. Afterstudying existing calibration techniques, a method for the calibration of allthe sensors (accelerometer, gyroscope, magnetometer and camera) is presented.The proposed solution allows to estimate the frame transformation between thedifferent sensors. It has the advantage of not requiring the use of any specialequipment. Furthermore, the integration of these sensors into a compact systemraises new difficulties. Under these conditions, the magnetic fields created bythe drone actuators disrupt magnetometer measurements. A new method isproposed to estimate and compensate for these magnetic disturbances. Thecompensation is dynamically adapted based on the state of the drone actuators.Finally, two applications of the system including an inertial unit and a cameraare presented : the construction of geo-referenced images mosaic and videostabilization. Both applications use measurements of inertial sensors and precisecalibration to perform a real-time processing for a very low computational cost.
75

Sensordatenfusion zur robusten Bewegungsschätzung eines autonomen Flugroboters

Wunschel, Daniel 15 March 2012 (has links) (PDF)
Eine Voraussetzung um einen Flugregler für Flugroboter zu realisieren, ist die Wahrnehmung der Bewegungen dieses Roboters. Diese Arbeit beschreibt einen Ansatz zur Schätzung der Bewegung eines autonomen Flugroboters unter Verwendung relativ einfacher, leichter und kostengünstiger Sensoren. Mittels eines Erweiterten Kalman Filters werden Beschleunigungssensoren, Gyroskope, ein Ultraschallsensor, sowie ein Sensor zu Messung des optischen Flusses zu einer robusten Bewegungsschätzung kombiniert. Dabei wurden die einzelnen Sensoren hinsichtlich der Eigenschaften experimentell untersucht, welche für die anschließende Erstellung des Filters relevant sind. Am Ende werden die Resultate des Filters mit den Ergebnissen einer Simulation und eines externen Tracking-Systems verglichen.
76

Methods and technologies for the analysis and interactive use of body movements in instrumental music performance

Visi, Federico January 2017 (has links)
A constantly growing corpus of interdisciplinary studies support the idea that music is a complex multimodal medium that is experienced not only by means of sounds but also through body movement. From this perspective, musical instruments can be seen as technological objects coupled with a repertoire of performance gestures. This repertoire is part of an ecological knowledge shared by musicians and listeners alike. It is part of the engine that guides musical experience and has a considerable expressive potential. This thesis explores technical and conceptual issues related to the analysis and creative use of music-related body movements in instrumental music performance. The complexity of this subject required an interdisciplinary approach, which includes the review of multiple theoretical accounts, quantitative and qualitative analysis of data collected in motion capture laboratories, the development and implementation of technologies for the interpretation and interactive use of motion data, and the creation of short musical pieces that actively employ the movement of the performers as an expressive musical feature. The theoretical framework is informed by embodied and enactive accounts of music cognition as well as by systematic studies of music-related movement and expressive music performance. The assumption that the movements of a musician are part of a shared knowledge is empirically explored through an experiment aimed at analysing the motion capture data of a violinist performing a selection of short musical excerpts. A group of subjects with no prior experience playing the violin is then asked to mime a performance following the audio excerpts recorded by the violinist. Motion data is recorded, analysed, and compared with the expert’s data. This is done both quantitatively through data analysis xii as well as qualitatively by relating the motion data to other high-level features and structures of the musical excerpts. Solutions to issues regarding capturing and storing movement data and its use in real-time scenarios are proposed. For the interactive use of motion-sensing technologies in music performance, various wearable sensors have been employed, along with different approaches for mapping control data to sound synthesis and signal processing parameters. In particular, novel approaches for the extraction of meaningful features from raw sensor data and the use of machine learning techniques for mapping movement to live electronics are described. To complete the framework, an essential element of this research project is the com- position and performance of études that explore the creative use of body movement in instrumental music from a Practice-as-Research perspective. This works as a test bed for the proposed concepts and techniques. Mapping concepts and technologies are challenged in a scenario constrained by the use of musical instruments, and different mapping ap- proaches are implemented and compared. In addition, techniques for notating movement in the score, and the impact of interactive motion sensor systems in instrumental music practice from the performer’s perspective are discussed. Finally, the chapter concluding the part of the thesis dedicated to practical implementations describes a novel method for mapping movement data to sound synthesis. This technique is based on the analysis of multimodal motion data collected from multiple subjects and its design draws from the theoretical, analytical, and practical works described throughout the dissertation. Overall, the parts and the diverse approaches that constitute this thesis work in synergy, contributing to the ongoing discourses on the study of musical gestures and the design of interactive music systems from multiple angles.
77

Contribution à la conception d'un système robotisé pour la télé-échographie / Contribution to the design of a robotized tele-echography system

Essomba, Terence 17 December 2012 (has links)
L’apparition de la télé-échographie à la fin des années 1990 a largement contribué à l’améliorationdes capacités de prise en charge des patients. Aujourd’hui, le laboratoire PRISME bénéficie d’unsavoir faire reconnu dans la conception de systèmes de télé-échographie robotisée. L’objectif deces travaux de thèse est d’apporter une contribution scientifique et technique au projet ANR-PROSIT,qui vise à la mise en oeuvre d’un robot de télé-échographie innovant. Une étude du geste du praticienen milieu clinique a été menée afin d’en déterminer les caractéristiques cinématiques. Réalisée àl’aide du système de capture de mouvement Vicon Nexus, cette analyse a contribué à l’établissementdes spécifications du futur robot. Sa structure mécanique a fait l’objet d’une attention particulière. Unearchitecture parallèle sphérique a été sélectionnée, étudiée puis optimisée via un algorithmegénétique en fonction des critères d’espace de travail, de dextérité et de compacité. L’architectureainsi obtenue est ensuite analysée sur des aspects de collisions et d’inaccessibilité. Pour le contrôlede ce robot, l’utilisation d’une interface haptique à l’aspect proche d’une sonde d’échographie estproposée. Dotée d’un système de retour d’effort et d’une centrale inertielle fiabilisée par un filtre deKalman adaptatif, cette nouvelle interface a été testée et validée par le système Vicon Nexus. / Since the end of the nineties, the tele-echography has been contributing to improve the taking carecapacities of patients. Today, the PRISME laboratory has a recognized expertise in the design ofrobotic tele-echography systems. The objective of this thesis is to provide scientific and technicalsupport to the ANR-PROSIT project. It aims to design of an innovative tele-echography robot. Anexpert gesture study has been carried out in clinical environment to determine its kinematiccharacteristics. It has been performed using the motion capture system Vicon Nexus and itcontributed to establish the specifications of the future robot. The mechanic structure of this robot hasbeen minutely taken in consideration. The spherical parallel mechanism has been selected, studiedand optimized using a genetic algorithm with respect of criterion such as workspace, dexterity andcompacity. The resulted architecture is then analyzed regarding collisions and inaccessibilityaspects. To control this robot, the use of a haptic device with the same shape of an ultrasound probeis proposed. It provides force feedback and it is instrumented with an inertial measurement unit,processed by an adaptative Kalman filter. This new interface has been tested and validated by ViconNexus system.
78

Integration of inertial navigation with global navigation satellite system / Integration of inertial navigation with global navigation satellite system

Štefanisko, Ivan January 2015 (has links)
This paper deals with study of inertial navigation, global navigation satellite system, and their fusion into the one navigation solution. The first part of the work is to calculate the trajectory from accelerometers and gyroscopes measurements. Navigation equations calculate rotation with quaternions and remove gravity sensed by accelerometers. The equation’s output is in earth centred fixed navigation frame. Then, inertial navigation errors are discussed and focused to the bias correction. Theory about INS/GNSS inte- gration compares different integration architecture. The Kalman filter is used to obtain navigation solution for attitude, velocity and position with advantages of both systems.
79

Sensordatenfusion zur robusten Bewegungsschätzung eines autonomen Flugroboters

Wunschel, Daniel 24 October 2011 (has links)
Eine Voraussetzung um einen Flugregler für Flugroboter zu realisieren, ist die Wahrnehmung der Bewegungen dieses Roboters. Diese Arbeit beschreibt einen Ansatz zur Schätzung der Bewegung eines autonomen Flugroboters unter Verwendung relativ einfacher, leichter und kostengünstiger Sensoren. Mittels eines Erweiterten Kalman Filters werden Beschleunigungssensoren, Gyroskope, ein Ultraschallsensor, sowie ein Sensor zu Messung des optischen Flusses zu einer robusten Bewegungsschätzung kombiniert. Dabei wurden die einzelnen Sensoren hinsichtlich der Eigenschaften experimentell untersucht, welche für die anschließende Erstellung des Filters relevant sind. Am Ende werden die Resultate des Filters mit den Ergebnissen einer Simulation und eines externen Tracking-Systems verglichen.
80

Inertialsensoren in der biomechanischen Gang- und Laufanalyse – Anforderungen an Sensoren und Algorithmik

Mitschke, Christian 20 November 2018 (has links)
Im Fokus dieser kumulativ angefertigten Dissertation stehen vier methodenorientierte biomechanische Studien, in welchen die potentiellen Fehlerquellen analysiert werden, die beim Einsatz von Inertialsensoren in der biomechanischen Gang- und Laufanalyse auftreten können. In den einzelnen Beiträgen werden die Einflüsse der Inertialsensoraufnahmefrequenz (Studie I) und des Messbereichs der Beschleunigungssensoren (Studie II) auf die kinematischen, kinetischen und räumlich-zeitlichen Parameter systematisch untersucht. Des Weiteren wird sich kritisch mit der Genauigkeit verschiedener Detektionsmethoden des initialen Bodenkontaktes (Studie III) sowie mit der Aussagekraft der maximalen Eversionsgeschwindigkeit (Studie IV) auseinandergesetzt. Um ein umfassendes Bild der Einflussgrößen zu erhalten, wurde in den Studien II, III und IV untersucht, ob die Materialcharakteristik der Laufschuhsohle die Genauigkeit der biomechanischen Parameter beeinflusst. Zudem wurde in Studie III geprüft, welchen zusätzlichen Effekt der Laufstil (Vor- und Rückfußlaufen) auf die Genauigkeit der initialen Bodenkontaktbestimmung hat sowie welchen Einfluss die Bewegungsgeschwindigkeit (Gehen und Laufen) auf die maximale Eversionsgeschwindigkeit nehmen kann (Studie IV). Die Ergebnisse der vier Untersuchungen werden am Ende dieser Arbeit in einem gemeinsamen Kontext diskutiert. Auf Grundlage der Erkenntnisse konnte eine Übersicht erstellt werden, welche sowohl die Mindestanforderungen an Inertialsensoren als auch die Einflussgrößen auf die Genauigkeit der biomechanischen Parameter enthält. Mit diesem Überblick erhalten Nutzer von Inertialsensoren (z.B. Sportler, Trainer, Mediziner und Wissenschaftler) bei der Planung einer Bewegungsanalyse die Unterstützung, die Sensoren mit der passenden Sensorspezifikation in Kombination mit den präzisesten Auswertealgorithmen auszuwählen. Zudem können die Informationen aus dieser Dissertation dazu genutzt werden, Erkenntnisse bereits publizierter Studien kritisch zu hinterfragen. / In previous studies, inertial sensors were used to investigate kinematic, kinetic, and spatio-temporal parameters during walking and running. The present cumulative doctoral thesis consists of four methodological studies. Two of the studies examine the influence of inertial sensor sampling rate (study I) and accelerometer operating range (study II) on the accuracy of biomechanical parameters. Another study investigated whether different published foot strike detection methods can accurately detect the time of initial ground contact (study III). The final study examined whether a single gyroscope can be used to accurately determine peak eversion velocity (study IV). In order to obtain a comprehensive view of the influencing factors, studies II, III and IV also investigated whether the material characteristics of the running shoe sole also influence the accuracy of the biomechanical parameters. Additionally, the effect of running style (forefoot or rearfoot) on the accuracy of foot strike detection methods was investigated in study III, and the effect of locomotion speed (walking, running slow up to running fast) on the accuracy of peak eversion velocity was examined in study IV. The results of the four investigations will be summarized and discussed in a common context. Based on the findings, an overview was prepared which contains both the minimum requirements for inertial sensors and also the influencing variables on the accuracy of the biomechanical parameters. This overview may assist users of inertial sensors (e.g. athletes, trainers, physicians, or scientists) in planning gait and running analyses to select inertial sensors with the appropriate specification in combination with the most accurate algorithms. In addition, the information from this dissertation can be used to critically consider the findings of published studies.

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