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Extended Target Tracking of Convex Polytope Shapes with Maneuvers and Clutter / Extended Target Tracking of Convex Polytope ShapesMannari, Prabhanjan January 2024 (has links)
High resolution sensors such as automotive radar and LiDAR have become prevalent in target tracking applications in recent times. Data from such sensors demands extended target tracking in which, the shape of the target is to be estimated along with the kinematics. Several applications benefit from extended target tracking, for example, autonomous vehicles and robotics.
This thesis proposes a different approach to extended target tracking compared to existing literature. Instead of a single shape descriptor to describe the entire target shape, different parts of the extended target are assumed to be distinct targets constrained by the target rigid body shape. This formulation is able to handle issues such as self-occlusion and clutter which, are not addressed sufficiently in literature. Firstly, a framework for extended target tracking is developed based on the formulation proposed. Using 2D convex hull as a shape descriptor, an algorithm to track 2D convex polytope shaped targets is developed. Further, the point target Probabilistic Multiple Hypotheses Tracker (PMHT) is modified to derive an extended target PMHT (ET-PMHT) equations to track 3D convex polytope shapes, using a Delaunay triangulation to describe the shape. Finally, the approach is extended to handle target maneuvers, as well as, clutter and measurements from the interior of the target.
In all three cases, the issue of self-occlusion is considered and the algorithms are still able to effectively capture the target shape. Since the true target center may not be observable, the shape descriptor abandons the use of target center in the state, and the shape is described by its boundary alone. The shape descriptors also support addition and deletion of faces, which is useful for handling newly visible parts of the target and clutter, respectively. The algorithms proposed have been compared with the existing literature for various scenarios, and it is seen that the proposed algorithms outperform, especially in the presence of self-occlusion. / Thesis / Candidate in Philosophy
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A Hardware-In-The-Loop Star Tracker Test BedHaraguchi, Ashley 01 June 2024 (has links) (PDF)
As the use of small satellites for advanced space missions continues to grow, the importance of low mass and cost three-axis attitude stabilization systems increases as well, with these systems requiring high accuracy attitude knowledge. Star trackers provide the most accurate attitude knowledge of any type of attitude sensor, but the high cost, size, and weight of commercial star trackers can be prohibitive to small satellite missions. Many simple star trackers have been developed using commercial off-the-shelf camera sensors and processing hardware, but the challenge remains in testing and characterizing these devices. A common solution is night sky tests, in which the star tracker is held up to the night sky to image the star field and perform attitude determination. Commercial star trackers, on the other hand, are regularly tested with manufacturer provided star field images that attach directly to the sensor. These methods, however, severely limit the sky conditions that can be used in testing. Night sky tests depend on weather and can only image regions of the sky the user has access to, while lab-based testing uses the few provided still images. This thesis presents a hardware-in-the-loop star tracker test bed developed for comprehensive ground-based testing of both in-house and commercial star trackers. The system consists of a small screen to display a star field, a simple in-house camera star tracker, and a microprocessor. This test bed allows any star field image to be simulated. The system is set up for use on a stationary tabletop, but its small size lends itself for use with a spacecraft dynamics platform, which can facilitate testing of control algorithms using real star tracker output.
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On the synchronization of two metronomes and their related dynamicsCarranza López, José Camilo [UNESP] 05 June 2017 (has links)
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Previous issue date: 2017-06-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nesta tese são investigadas, teórica e experimentalmente, a sincronização em fase e a sincronização em anti-fase de dois metrônomos oscilando sobre uma base móvel, a partir de um modelo aqui proposto. Uma descrição do funcionamento do mecanismo de escapamento dos metrônomos é feita, junto a um estudo da relação entre este e o oscilador de van der Pol. Também uma aproximação experimental do valor do amortecimento do metrônomo é fornecida. A frequência instantânea das respostas, numérica e experimental, do sistema é usada na analise. A diferença de outros trabalhos prévios, os dados experimentais têm sido adquiridos usando vídeos dos experimentos e extraídos com ajuda do software Tracker. Para investigar a relação entre as condições iniciais do sistema e seu estado final de sincronização, foram usados mapas bidimensionais chamados ‘basins of attraction’. A relação entre o modelo proposto e um modelo prévio também é mostrada. Encontrou-se que os parâmetros relevantes em relação a ambos os tipos de sincronização são a razão entre a massa do metrônomo e a massa da base, e o amortecimento do sistema. Tem-se encontrado, tanto experimental quanto teoricamente, que a frequência de oscilação dos metrônomos aumenta quando o sistema sincroniza-se em fase, e se mantém a mesma de um metrônomo isolado quando o sistema sincroniza-se em anti-fase. A partir de simulações numéricas encontrou-se que, em geral, incrementos no amortecimento do sistema levam ao sistema se sincronizar mais em fase do que em anti-fase. Adicionalmente se encontrou que, para dado valor de amortecimento, diminuir a massa da base leva a uma situação em que a sincronização em anti-fase é mais comum do que a sincronização em fase. / This thesis concerns a theoretical and experimental investigation into the synchronization of two coupled metronomes. A simplified model is proposed to study in-phase and anti-phase synchronization of two metronomes oscillating on a mobile base. A description of the escapement mechanism driving metronomes is given and its relationship with the van der Pol oscillator is discussed. Also an experimental value for the damping in the metronome is determined. The instantaneous frequency of the responses from both numerical and experimental data is used in the analysis. Unlike previous studies, measurements are made using videos and the time domain responses of the metronomes extracted by means of tracker software. Basins of attraction are used to investigate the relationship between initial conditions, parameters and both final synchronization states. The relationship between the model and a previous pendulum model is also shown. The key parameters concerning both kind of synchronization have been found to be the mass ratio between the metronome mass and the base mass, and the damping in the system. It has been shown, both theoretically and experimentally, that the frequency of oscillation of the metronomes increases when the system reaches in-phase synchronization, and is the same as an isolated metronome when the system synchronizes in anti-phase. From numerical simulations, it has been found that, in general, increasing damping leads the system to synchronize more in-phase than in anti-phase. It has also been found that, for a given damping value, decreasing the mass of the base results in the situation where anti-phase synchronization is more common than in-phase synchronization.
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Ensinando cinemática através da análise de movimentos em vídeos de captura de gamesSilva Neto, Manoel Coelho da 21 August 2017 (has links)
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Manoel Coelho da Silva Neto - Produto Final.pdf: 4043748 bytes, checksum: ed0f262e5d26eb90ede963337eadcabc (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Ciências Exatas. Programa de Pós-Graduação em Ensino de Física. Volta Redonda,RJ. / Esta dissertação apresenta uma atividade de ensino centrada no aluno para tópicos de
cinemática, utilizando Tecnologias de Informação e Comunicação (TICs) e o game
Angry Birds como motivador do engajamento do aluno no processo de
aprendizagem. Em nosso projeto, conduzido no Colégio Estadual Conde Pereira
Carneiro, em Angra dos Reis, RJ, os alunos cumpriram atividades de recuperação
escolar em aulas vagas do próprio turno de presença, onde, capturando uma sessão de
jogo de Angry Birds em vídeo, posteriormente analisavam os movimentos nele
contidos no software Tracker. Com isso, trabalharam-se todos os conceitos
fundamentais da cinemática, como posição, deslocamento, velocidade e aceleração,
além de tópicos da cinemática, como movimento uniforme, acelerado e de projéteis.
Os resultados sugerem que este tipo de atividade é efetiva em promover uma maior
aproximação do aluno à disciplina de Física, proporcionando engajamento e
estimulando autonomia e independência no aprendizado do estudante, qualidades
desejáveis em qualquer metodologia de ensino. / This work presents a student-centered teaching activity for teaching kinematics,
using Communication and Information Tecnologies, and the game Angry Birds as
the motivator for student engagement in the learning process. Our project, conducted
at Colégio Estadual Conde Pereira Carneiro, in Angra dos Reis, RJ, consisted of
sessions where students captured a playing session of Angry Birds in video, with
later analysis of the motion of the birds through the software Tracker. They dealt,
thus, with all the fundamental concepts of kinematics, such as position, displacement,
velocity and acceleration, as well as with topics specific to kinematics, such as
uniform and accelerated motion and projectile motion. The results suggest that this
kind of activity promotes a greater closeness to the discipline of Physics, as well as
engagement and independence in learning, something highly desirable in teaching
and learning.
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Look2Hook - A Comparative Study of Eye-tracker and Mouse Based Object Selection in a Complex Environment / Look2Hook - En Komparativ Studie av Eye-tracker och Musbaserad Objekt Selektion i en Komplex MiljöErlandsson, Oskar January 2021 (has links)
In this thesis the Tobii eye-tracker 4L was used to investigate how well eye-tracking solutions such as a confirmation-click and dwell-time algorithm compares to the standard mouse input device when performing selection tasks in a map environment. In order to distinguish the different complexity one could face, two user cases are proposed. Scenario one includes non clustered objects. Scenario two include clustered occluded objects. A user study with nine different participants where conducted in order to compare the execution times and find out how error prone the different methods were. Each test participant performed eight different tests, three in the non-clustered scenario and five in the clustered scenario. In two of the tests in the clustered scenario test participants were aided with zooming through a zoom algorithm. The methods was evaluated by calculating the average execution times and errors along with the corresponding standard deviations. In order to grasp the users experience a subjective cognitive load score was calculated with the help of a questionnaire. The eye-tracker methods was found to be competitive in comparison to mouse interaction in the more simple non-clustered case. However, in a more complex scenario such as the clustered case the mouse interaction had the lowest average completion time and cognitive load score. A different type of selection behaviour was discovered among the test participants in the clustered scenario due to the difference in precision between the eye-tracker and mouse interaction. Finally interesting areas to consider in the future is presented and discussed. / I denna avhandling användes en Tobii eye-tracker 4L för att undersöka hur väl eye-tracking metoder så som en bekräftelseklick och dwell-time algoritm jämför sig med standard mus interaktion vid objekt selektion i en kartmiljö. För att urskilja variationen i komplexitet man kan möta föreslås två olika användarfall. Scenario ett inkluderar objekt som är distinktivt separerade och därav ej grupperade. Scenario två inkluderar grupperade samt ockluderade objekt. En användarstudie med nio olika deltagare genomfördes för att jämföra exekveringstiderna och ta reda på hur felbenägna de olika metoderna var. Varje testdeltagare utförde åtta olika tester, tre i det icke-grupperade scenariot och fem i det grupperade scenariot. I två av testerna i det grupperade scenariot fick deltagarna hjälp med att zooma genom en zoomalgoritm. Metoderna utvärderades genom att beräkna de genomsnittliga exekveringstiderna samt antal fel tillsammans med motsvarande standardavvikelser. För att förstå hur användarna upplevde de olika metoderna togs en subjektiv kognitiv belastningspoäng fram genom ett frågeformulär. Eye-tracker metoderna var konkurrenskraftiga i jämförelse med musinteraktion i det enklare fallet där objekt ej var grupperade. I ett mer komplext scenario, såsom i det grupperade fallet, hade dock musinteraktionen den lägsta genomsnittliga exekveringstiden och kognitiva belastningspoängen. En annan typ av selektions beteende upptäcktes bland testdeltagarna i det grupperade scenariot på grund av skillnaden i precision mellan eye-trackern och musinteraktionen. Slutligen presenteras och diskuteras intressanta områden att överväga vid framtida arbeten.
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Tracking Under Countermeasures Using Infrared ImageryModorato, Sara January 2022 (has links)
Object tracking can be done in numerous ways, where the goal is to track a target through all frames in a sequence. The ground truth bounding box is used to initialize the object tracking algorithm. Object tracking can be carried out on infrared imagery suitable for military applications to execute tracking even without illumination. Objects, such as aircraft, can deploy countermeasures to impede tracking. The countermeasures most often mainly impact one wavelength band. Therefore, using two different wavelength bands for object tracking can counteract the impact of the countermeasures. The dataset was created from simulations. The countermeasures applied to the dataset are flares and Directional Infrared Countermeasures (DIRCMs). Different object tracking algorithms exist, and many are based on discriminative correlation filters (DCF). The thesis investigated the DCF-based trackers STRCF and ECO on the created dataset. The STRCF and the ECO trackers were analyzed using one and two wavelength bands. The following features were investigated for both trackers: grayscale, Histogram of Oriented Gradients (HOG), and pre-trained deep features. The results indicated that the STRCF and the ECO trackers using two wavelength bands instead of one improved performance on sequences with countermeasures. The use of HOG, deep features, or a combination of both improved the performance of the STRCF tracker using two wavelength bands. Likewise, the performance of the ECO tracker using two wavelength bands was improved by the use of deep features. However, the negative aspect of using two wavelength bands and introducing more features is that it resulted in a lower frame rate.
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A study for the development of a laser tracking system utilizing multilateration for high accuracy dimensional metrologyGreeff, Gabriel Pieter 03 1900 (has links)
MScEng / Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Accurate dimensional measurement devices are critical for international industrial
competitiveness for South Africa. An overview of all the necessary
components of a laser tracking system using a multilateration technique for
very accurate dimensional metrology is presented.
A prototype laser tracker station was built to further investigate this type
of system. The prototype successfully tracks a target within a volume of at
least 200 200 200 mm3, approximately 300 mm away from the tracker.
This system includes the mechanical design of a prototype tracker station,
electronic implementation of ampli cation and motor control circuits, a tracking
control algorithm, microcontroller programming and interfacing, as well as
a user interface.
Kinematic modelling along with Monte Carlo analyses nd the main error
source of such a tracker as the beam steering mechanism gimbal axes misalignment.
Multilateration is also motivated by the results found by the analysis.
Furthermore, an initial sequential multilateration algorithm is developed
and tested. The results of these tests are promising and motivate the use of
multilateration over a single beam laser tracking system. / AFRIKAANSE OPSOMMING: Dit is van kritieke belang dat Suid-Afrika akkurate dimensionele metingstoestelle
ontwikkel vir internasionale industriële medinging. 'n Oorsig van al die nodige
komponente vir 'n Laser-Volgsisteem, wat slegs van multilaterasie gebruik
maak om baie akkurate drie dimensionele metings te kan neem, word in hierdie
projek voorgestel.
'n Prototipe Laser-Volgsisteem-stasie word gebou om so 'n sisteem verder
te ondersoek. Die prototipe slaag wel daarin om 'n teiken, binne 'n volume
van 200 200 200 mm3 op 'n afstand van omtrent 300 mm te volg. Die
sisteem sluit die meganiese ontwerp van die sodanige stasie, elektroniese seinversterking,
motorbeheer, 'n volgingsbeheer algoritme, mikroverwerker programeering
en intergrasie, asook 'n gebruikerskoppelvlak program in.
Kinematiese modelering, tesame met Monte Carlo simulasies, toon aan dat
die hoof oorsaak van metingsfoute by so 'n stasie by die rotasie-asse van die
laserstraal-stuurmeganisme, wat nie haaks is nie, lê. Die multilaterasie metode
word ook verder ondersteun deur dié modelering.
'n Algoritme wat sekwensiële multilateratsie toepas word boonop ontwikkel
en getoets. Die resultate van die toetse dui daarop dat die algoritme funksioneer
en dat daar voordele daarin kan wees om so 'n metode in plaas van 'n
Enkelstraal-Volgsisteem te gebruik.
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OPTICAL SLIP-RING CONNECTORXu, Guoda, Bartha, John M., McNamee, Stuart, Rheaume, Larry, Khosrowabadi, Allen 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Current ground-based tracking systems at the DoD test and training ranges require
transmission of a variety of signals from rotating platform to fixed control and process
center. Implementation of commercial off the shelf (COTS) solution for transmitting high-speed,
multiple-channel data signals over a rotational platform prompt the development of
an advanced electro-optic hybrid rotating-to-fixed information transmission technology.
Based on current demand, an Air Force-sponsored Small Business Innovative Research
(SBIR) contract has been awarded to Physical Optics Corporation (POC) to modify
existing tracking mounts with a unique electro-optic hybrid rotary joint (EOHRJ). The
EOHRJ under current development is expected to provide the following features: 1)
include a specially designed electrical slip-ring, which is able to accommodate hundreds of
transmission channels, including electrical power, control, feedback, and low-speed data
signals; 2) include an optical fiber slip-ring which, by incorporating with electrical time
division mulitplexing (TDM) and optical wavelength division multiplexing (WDM)
technologies, is able to provide multiple channel, high data rate (over gigabits per second),
and bi-directional signal transmission; and 3) is designed to be reliable for harsh
environmental operation, adaptive to stringent size requirement, and accommodating to
existing electrical and mechanical interfaces.
Besides the military use, other possible commercial applications include on board
monitoring of satellite spinners, surveillance systems, instrumentation and multi spectral
vision systems, emergency/medical instruments, remote sensing, and robotics.
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Detector Development for the High Luminosity Large Hadron ColliderRieger, Julia 02 August 2016 (has links)
Um das Entdeckungspotential des Large Hadron Colliders auszunutzen, wird er beginnend 2024 zum High Luminosity Large Hadron Collider ausgebaut. Neue Detektorherausforderungen entstehen durch die höhere instantane Luminosität und den höheren Teilchenfluss. Der neue ATLAS Inner Tracker wird den aktuellen Spurdetektor ersetzen, um mit diesen Herausforderungen umzugehen. Es gibt viele Pixeldetektortechnologien zur Teilchenspurerkennung, jedoch muss ihre Eignung für den ATLAS Inner Tracker untersucht werden. Aktive Hochspannungs-CMOS-Sensoren, die in industriellen Prozessen produziert werden, bieten eine schnelle Auslese und Strahlenhärte. In dieser Arbeit wird der HV2FEI4v2-Sensor, der kapazitiv mit dem ATLAS-FE-I4-Auslesechip gekoppelt ist, dahingehend charakterisiert, ob er für eine Verwendung in einer der äußeren Lagen des ATLAS Inner Tracker geeignet ist. Schlüsselgrößen des Prototypens, wie die Treffereffizienz und die Subpixelentschlüsselung, werden untersucht. Der frühe HV2FEI4v2-Prototyp zeigt vielversprechende Ergebnisse, die als Ausgangspunkt für weitere Entwicklungen dienen. Aktive CMOS-Sensoren stellen einen möglichen Kandidaten für einen kosteneffizienten Detektor für den High Luminosity Large Hadron Collider.
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Odpověď zrakového analyzátoru při řízení vozidla v reálných podmínkách a na simulátoru při paralelní motorické úloze. / The response of the visual system when driving a car in real conditions and in a simulator during a parallel motor task.Čiháková, Lucie January 2011 (has links)
Work title: The response of the visual system when driving a car in real conditions and in a simulator during a parallel motor task. Aims: To implement a laboratory measurement in a driving simulator and in real conditions during a parallel motor task. To track the response of the visual system during the task and to determine potential differences in the response of the visual system and in the speed in the simulator and in the real car environment. Methods: The laboratory measurement was realized in a driving simulator OCTAVIA II. The measurement in real conditions was realized in Škoda Octavia as well. The eye-tracking method was used to track the drivers` eyes. Results: In the simulator the more experienced driver managed to do the parallel motor task within a shorter period of time than the less experienced driver, lower frequency of looks at the radio during the tasks with the more experienced driver was not proved. There was not an evidence of more balanced speed during the drive with the more experienced driver in the simulator. On the average the driver spent shorter time doing the tasks in the real environment than in the simulator and the total number of looks at the radio was lower. The speed of the drive in the real environment was lower than the speed in the simulator. Key words:...
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