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Dissertationen zum Thema „Optical sensor system“
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1
Hua, Ping. „Integrated optical fluorescence multi-sensor system“. Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/70934/.
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Research on fluorescence-based integrated optical immunoassay multisensing systems has gained growing interest in the last ten years. This is because the systems have the potential to simultaneously detect multiple analytes in a single measurement, and the techniques involved are fast, robust and cost-effective. Therefore they have the potential to replace conventional chromatographic techniques, as the monitoring systems for the rapid assessment of water or food samples. Other areas, such as clinical diagnostics or forensic science also have a demand for highly multiplexed analytical systems. This thesis presents a novel 32-analyte integrated optical fluorescence-based multisensor, and its integration to an automated multi-bio-sensing system. This system is primarily used for detecting organic pollutants in river water. A detailed study was also carried out with a CCD detector system, used to replace the fibre collection and photodiode array system and allow straight forward extension to more than 32 analytes. A direct comparison between these two systems is also presented
2
Fan, Chenjun. „Fiber optic sensor based on dual ring resonator system /“. Online version of thesis, 1992. http://hdl.handle.net/1850/11070.
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3
Murtaza, Ghulam. „Dual wavelength referenced intensity modulated optical fibre sensor system“. Thesis, Manchester Metropolitan University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358834.
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4
Yang, Yatao. „Development of a distributed optical fibre pH sensor system“. Thesis, Glasgow Caledonian University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321322.
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5
Ogundana, Olatokunbo Omodele. „Automated calibration of multi-sensor optical shape measurement system“. Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/33688.
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A multi-sensor optical shape measurement system (SMS) based on the fringe projection method and temporal phase unwrapping has recently been commercialised as a result of its easy implementation, computer control using a spatial light modulator, and fast full-field measurement. The main advantage of a multi-sensor SMS is the ability to make measurements for 360° coverage without the requirement for mounting the measured component on translation and/or rotation stages. However, for greater acceptance in industry, issues relating to a user-friendly calibration of the multi-sensor SMS in an industrial environment for presentation of the measured data in a single coordinate system need to be addressed. The calibration of multi-sensor SMSs typically requires a calibration artefact, which consequently leads to significant user input for the processing of calibration data, in order to obtain the respective sensor's optimal imaging geometry parameters. The imaging geometry parameters provide a mapping from the acquired shape data to real world Cartesian coordinates. However, the process of obtaining optimal sensor imaging geometry parameters (which involves a nonlinear numerical optimization process known as bundle adjustment), requires labelling regions within each point cloud as belonging to known features of the calibration artefact. This thesis describes an automated calibration procedure which ensures that calibration data is processed through automated feature detection of the calibration artefact, artefact pose estimation, automated control point selection, and finally bundle adjustment itself.
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Juarez, Juan C. „Distributed fiber optic intrusion sensor system for monitoring long perimeters“. Thesis, [College Station, Tex. : Texas A&M University, 2005. http://hdl.handle.net/1969.1/ETD-TAMU-1702.
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7
Al, Mahdawi Basil Mohamed Nouri. „Senior monitoring by using sensors network and optical metrology“. Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCD085.
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L’objectif du travail de cette thèse est la contribution au développement de nouvelles techniques dans le domaine dessystèmes de détection sans marqueur pour une utilisation dans trois domaines vitaux de la santé en utilisant des capteursinnovants et peu coûteux. Pour la réalisation de nos objectifs nous avons eu recours principalement à de l’électroniqueembarquées et du traitement du signal en utilisant le capteur Kinect. Des résultats encourageants ont été obtenus et sontprésentés tout au long de cette thèse. Dans la première partie de ce travail, nous présentons un nouveau système desurveillance visuelle sans marqueur en temps réel pour détecter et suivre les personnes âgées et surveiller leurs activitésdans leur environnement intérieur en utilisant un réseau de capteurs Kinect. Le système identifie également l’événementde chute des personnes âgées sous surveillance. Dans la deuxième partie nous utilisons également le capteur Kinectmais cette fois ci pour la détection sans marqueur des mouvements de la tête d’un patient lors d’un examen utilisant LaTomographie par Emission de Positons (CT/PET) du cerveau. Ce travail est basé sur la compensation de la dégradationde l’image TEP due aux mouvements de la tête du patient. Pour nos essais un cobaye dit « fantôme » a été réalisé,les résultats sur le fantôme sont prometteur ce qui a donné lieu à un test sur un vrai patient volontaire. Les résultatsfinaux montrent l’efficacité de ce nouveau système. La troisième partie du travail présente la mise en oeuvre d’un nouveausystème intelligent pour contrôler un fauteuil roulant électrique par des mouvements spéciaux de la tête toujours sansmarqueur. Un algorithme adapté est conçu pour détecter en continu les degrés des mouvements du visage en utilisant lecapteur Kinect. Fautes de fauteuil roulant électrique, le système a été testé sur un véhicule radio commandéThe objective of the work of this thesis is the contribution in developing novel technical methods in the field of marker-lesssensing systems for use in three vital health areas by using new inexpensive sensors. Several scientific areas are involvedin achieving our objective such as; electronics and signal processing by using the Kinect sensor. Encouraging results wereachieved as presented throughout this thesis. In the first part of this work we present a new real-time marker-less visualsurveillance system for detecting and tracking seniors and monitoring their activities in the indoor environment by usingnetwork of Kinect sensors. The system also identifies the fall event with the elderly. In the second part, we present anew approach for a marker-less movement detection system for influential head movements in the brain Positron EmissionTomography imaging (CT/PET) by employing the Kinect sensor. This work addresses the compensation of the PET imagedegradation due to subject’s head movements. A developed particular phantom and volunteer studies were carried out.The experimental results show the effectiveness of this new system. The third part of the work presents the design andimplementation of a new smart system for controlling an electric wheelchair by special mark-less head movements. Anadaptable algorithm is designed to continuously detect the rotation degrees of the face pose using the Kinect sensor inreal-time that are interpreted as controlling signals through a hardware interface for the electric wheelchair actuators
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Gunnam, Kiran Kumar. „A DSP embedded optical naviagtion system“. Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969/13.
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9
Toh, Edwin. „Implementation of an optical readout system for high-sensitivity terahertz microelectromechanical sensor array“. Thesis, Monterey, California: Naval Postgraduate School, 2014. http://hdl.handle.net/10945/44019.
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Approved for public release; distribution is unlimitedIn this thesis, an optical readout scheme was successfully developed based on the Fourier 4F optical configuration and integrated with a custom-fabricated microelectromechanical system (MEMS)-based, terahertz (THz), detector array. The MEMS THz detector array and 4F Fourier optics were able to transduce the THz scene into an optical signal that was captured by a commercial charged coupled device (CCD) camera for generating images. A quantum cascade laser (QCL) provided the THz illumination for generating images while post-image processing performed background subtraction in order to obtain the THz scene. The Fourier 4F optical readout system that was implemented was able to profile the general shape of the QCL beam pattern and displayed good linearity of response of about 23 gray level values per Kelvin. The concept of optical readout from a micromechanical sensor array was also validated.
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Cusworth, S. D. „An extrinsic optical fibre sensor system for the measurement of pressure and temperature“. Thesis, Manchester Metropolitan University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370938.
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11
Musa, Shah M. „Real-Time Signal Processing and Hardware Development for a Wavelength Modulated Optical Fiber Sensor System“. Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30679.
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The use of optical fiber sensors is increasing widely in civil, industrial, and military applications mainly due to their, (a) miniature size, (b) high sensitivity, (c) immunity from electro-magnetic interference, (d) resistance to harsh environments, (e) remote signal processing ability, and, (f) multiplexing capabilities. Because of these advantages a variety of optical fiber sensing techniques have evolved over the years having potentials for myriad of applications. One very challenging job, for any of these optical fiber sensing techniques, is to implement a stand alone system with the design and development of all the signal processing models along with the necessary hardware, firmware, and software satisfying the real-time signal processing requirements. In this work we first develop the equations for the system model of the wavelength modulated extrinsic Fabry-Perot interferometric (EFPI) optical fiber sensor, and then design and build all the hardware and software necessary to implement a stand-aPh. D.
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Adil, Fatime Zehra. „Development Of An Optical System Calibration And Alignment Methodology Using Shack-hartmann Wavefront Sensor“. Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615591/index.pdf.
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Shack-Hartmann wavefront sensors are commonly used in optical alignment, ophthalmology,
astronomy, adaptive optics and commercial optical testing. Wavefront error measurement yields
Zernike polynomials which provide useful data for alignment correction calculations.
In this thesis a practical alignment method of a helmet visor is proposed based on the wavefront error
measurements. The optical system is modeled in Zemax software in order to collect the Zernike
polynomial data necessary to relate the error measurements to the positioning of the visor. An
artificial neural network based computer program is designed and trained with the data obtained from
Zernike simulation in Zemax software and then the program is able to find how to invert the
misalignments in the system. The performance of this alignment correction method is compared with
the optical test setup measurements.
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Oh, Ki Dong. „Optical Fiber Fabry-Perot Interferometer based Sensor Instrumentation System for Low Magnetic Field Measurement“. Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/29687.
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This dissertation proposes a miniaturized optical fiber based sensor system for the measurement of 3-dimensional vector magnetic fields. The operation of the sensor system is based on the detection of magnetostrictive dimensional changes in the sensor gage using a modified extrinsic Fabry-Perot Interferometer configuration. Because of the magnetostrictive reflector the gap length depends on the magnetic fields applied to the sensor. Since the diameter of the magnetostrictive sensor gage is 125 micrometer which is the same as that of the input/output fiber, the sensor is simply constructed by inserting the sensor gage and the input/output fiber into a small glass tube. The glass tube serves as both an aligner for the sensor gage and input/out fiber, and a passive temperature compensator. In addition, it also enhances the mechanical strength and compactness of the sensor. This sensor design shows 98 percent suppression of the thermally induced sensor output changes. The linear output of the sensor system is enhanced by transverse field annealing which increases magnetostrictive induction in the ferromagnetic sensor gage material and controls the sensor gage geometry. A 5-times increase in sensor sensitivity is obtained with the transverse field annealing and the use of a new magnetostrictive material. A modified sensor gage endface demonstrates 92 percent of fringe visibility, which further improves the performance of the interferometer. The signal fading in the interferometric sensors at the peak or bottom of a fringe is reduced by using a quadrature signal demodulation method. The system has been shown to have a resolution better than 100 nT over a measurement range from 100 to 40,000 nT. This research is supported financially by the Phillips Laboratory of the U.S. Air Force.Ph. D.
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Raman, Baranidharan. „Sensor-based machine olfaction with neuromorphic models of the olfactory system“. Diss., Texas A&M University, 2005. http://hdl.handle.net/1969.1/4984.
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Electronic noses combine an array of cross-selective gas sensors with a pattern recognition engine to identify odors. Pattern recognition of multivariate gas sensor response is usually performed using existing statistical and chemometric techniques. An alternative solution involves developing novel algorithms inspired by information processing in the biological olfactory system. The objective of this dissertation is to develop a neuromorphic architecture for pattern recognition for a chemosensor array inspired by key signal processing mechanisms in the olfactory system. Our approach can be summarized as follows. First, a high-dimensional odor signal is generated from a chemical sensor array. Three approaches have been proposed to generate this combinatorial and high dimensional odor signal: temperature-modulation of a metal-oxide chemoresistor, a large population of optical microbead sensors, and infrared spectroscopy. The resulting high-dimensional odor signals are subject to dimensionality reduction using a self-organizing model of chemotopic convergence. This convergence transforms the initial combinatorial high-dimensional code into an organized spatial pattern (i.e., an odor image), which decouples odor identity from intensity. Two lateral inhibitory circuits subsequently process the highly overlapping odor images obtained after convergence. The first shunting lateral inhibition circuits perform gain control enabling identification of the odorant across a wide range of concentration. This shunting lateral inhibition is followed by an additive lateral inhibition circuit with center-surround connections. These circuits improve contrast between odor images leading to more sparse and orthogonal patterns than the one available at the input. The sharpened odor image is stored in a neurodynamic model of a cortex. Finally, anti-Hebbian/ Hebbian inhibitory feedback from the cortical circuits to the contrast enhancement circuits performs mixture segmentation and weaker odor/background suppression, respectively. We validate the models using experimental datasets and show our results are consistent with recent neurobiological findings.
15
Yussof, Hanafiah, und Masahiro Ohka. „Application of stiffness control algorithm for dexterous robot grasping using optical three-axis tactile sensor system“. IEEE, 2009. http://hdl.handle.net/2237/13948.
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16
Crolla, Paul. „On a dual wavelength optical sensor system for measuring strain and temperature simultaneously in tokamak port plug“. Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24278.
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A large variety of sources will provide energy, including nuclear fusion energy from tokamak type reactors; still at a research stage of development to produce 500 MW of energy. The reactor's structure will be affected by temperature changes and ionising radiation (neutrons produced by the burning plasma); it is therefore necessary to instrument the structure with long lasting, accurate, temperature and strain monitoring devices. This thesis demonstrates that using electrical sensors in the supporting structures of a fusion reactor for measuring strain and temperature will be strongly affected by the ionising radiation and the electromagnetic fields. This is because it was found that errors of over 100% can be present on the measurements due to combined electromagnetic and radiation effects. An optical fibre sensor was constructed to a strain resolution of ±10uε and temperature resolution of ±5°C. The fibre sensor is an off the shelf solution dual-wavelength fibre Bragg grating. The thesis proposes a method of coating the fibre in layers of silver and copper to protect this sensor. A new method of embedding the fibre in a stainless steel piece is described using a silver solder to couple the fibre with the steel increasing its temperature and strain sensitivity by approximately three times, with the solder melted using an induction heater. To measure the temperature and strain response from the fibre Bragg grating a broadband optical filter was used as a real-time interrogation system. Data capture and analysis software solution was created running at 30Hz and ~1pm resolution; temperature and strain requirements were met. This work describes a method of performing measurements of strain and temperature not subject to electromagnetic interference, with good electrical isolation possible and capable of operating in a near vacuum. The sensor package provides a robust, weldable solution for connecting the sensor to the port plug structure and/or plasma instrumentation equipment that will provide regular repeatable measurements of strain and temperature.
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Bäcklund, Tomas. „Development and validation of a system for clinical assessment of gait cycle parameter in patients with idiopathic normal pressure hydocephalus“. Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-82891.
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A number of parameters have been identified as characteristic of the walking pattern in patients with INPH. Most of these have been identified through qualitative surveys and manually conducted test batteries. In order to obtain quantitative, standardized and objective measures, which enable studies based on larger patient populations and comparable results, there is a need for a user-friendly system that can measure specific key parameters over time in a reliable manner in everyday clinical work. Step height, width and the variability in the gait cycle are such parameters which are interesting research areas for this group of patient. Problems with balance and gait are very common in other patient groups as well, particularly in neurological diseases such as Parkinson's disease, multiple sclerosis and stroke. This is the reason that the development of this gait analyzer is performed. Giving access to a simple and objective method for estimating gait and balance ability in clinical routine investigations would increase the ability to provide the right kind of treatment, confirm treatment results, and conducting larger research studies. Therefore, this equipment can contribute to the assessment of diseases which contain impaired gait. As a first test of the usability and for the validation of accuracy and repeatability of the equipment a group of healthy volunteers was used. Results from tests on healthy subjects show god repeatability between measurements, for step width at normal gait the difference was -0,2 ±0,34 cm (mean, ±SD) and step height 0,69 ±3,34 cm. The stride time variability in the healthy group where very small 0,00048 ±0,00028 s2 with a difference between test of 0,000019 ±0,00038 s2. Three pilot patients have been tested where we have clearly seen indications of increased stride time variability and reduced step height.
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Pickering, Todd Michael. „Methods for Validation of a Turbomachinery Rotor Blade Tip Timing System“. Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/47496.
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This research developed two innovative test methods that were used to experimentally evaluate the performance of a novel blade tip timing (BTT) system from Prime Photonics, LC. The research focused on creating known blade tip offsets and tip vibrations so that the results from a BTT system can be validated. The topic of validation is important to the BTT field as the results between many commercial systems still are not consistent. While the system that was tested is still in development and final validation is not complete, the blade tip offset and vibration frequency validation results show that this BTT system will be a valuable addition to turbomachinery research and development programs once completed.
For the first test method custom rotors were created with specified blade tip offsets. For the blade tip offset alternate measurement, the rotors were optically scanned and analyzed in CAD software with a tip location uncertainty of 0.1 mm. The BTT system agreed with the scanned results to within 0.13 mm. Tests were also conducted to ensure that the BTT system identified and indexed the blades properly.
The second developed test method used an instrumented piezoelectric blade to create known dynamic deflections. The active vibration rotor was able to create measureable deflection over a range of frequencies centered on the first bending mode of the blade. The results for the 110 Hz, 150 Hz, 180 Hz first bending resonance, 200 Hz, and 1036 Hz second bending resonance cases are presented. A strain gage and piezoelectric sensor were attached to the active blade during the dynamic deflection tests to provide an alternate method for determining blade vibration frequency. The BTT system correctly identified the active blade excitation frequencies as well as a 120 Hz frequency from the drive motor.
This thesis also explored applying BTT methods and testing to more realistic blade geometry and vibration. Blade vibrations are usually classified by their frequency relative to the rotation speed. Synchronous vibrations are integer multiples of the rotational speed and are often excited by struts or vanes fixed to the engine case. For this reason, special probe placement algorithms were explored that use sine curve fitting to optimize the probe placement. Knowing how the blade will vibrate at operation before testing is critical as well. In preparation for future research, ANSYS Mechanical was used to predict the first three modes of a PT6A-28 first stage rotor blade at 1,966, 5,539, and 7,144 Hz. These frequencies were validated to within 4% using scanning laser vibrometry. The simulation was repeated at speed to produce a Campbell Diagram to highlight synchronous excitation crossings.Master of Science
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Jia, Fei. „Multivariable And Sensor Feedback Based Real-Time Monitoring And Control Of Microalgae Production System“. Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/579045.
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A multi-wavelength laser diode based optical sensor was designed, developed and evaluated for monitoring and control microalgae growth in real-time. The sensor measures optical density of microalgae suspension at three wavelengths: 650 nm, 685 nm and 780 nm, which are commonly used for estimating microalgae biomass concentration and chlorophyll content. The sensor showed capability of measuring cell concentration up to 1.05 g L⁻¹ without sample dilution or preparation. The performance of the sensor was evaluated using both indoor photobioreactors and outdoor paddle wheel reactors. It was shown that the sensor was capable of monitoring the dynamics of the microalgae culture in real-time with high accuracy and durability. Specific growth rate (μ) and ratios of optical densities (OD ratios) at different wavelengths were calculated and were used as good indicators of the health of microalgae culture. A series of experiments was conducted to evaluate the sensor's capability of detecting environmental disturbances in microalgae systems, for instance, induced by dust or Vampirovibrio chlorellavorus, a bacteria found to cause crash of microalgae culture. Optical densities measured from the sensor were insensitive to the amount of dust that consisted of 59.7% of dry weight of microalgae in the system. However, the sensor was able to detect multiple events of introduction of dust timely by μ and OD ratios. The sensor was also capable of detecting subtle changes of culture in color that leads to a total crash of the culture before it can be differentiated by naked eye. The sensor was further integrated into an existing outdoor raceway to demonstrate the sensor's potential of being a core component to control microalgae production system. A real-time monitoring and control program along with a graphical user interface (GUI) was developed for a central control station aiming at improving resource use efficiency for biomass production.
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Stan, Nikola. „Complete Measurement System for Measuring High Voltage and Electrical Field Using Slab-Coupled Optical Fiber Sensors“. BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7053.
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A slab-coupled optical fiber sensor (SCOS) falls into a narrow class of all-dielectric optical fiber electric field sensors, which makes it a perfect candidate for measurements of high electric fields in environments where presence of conductors is highly perturbing to the system under test. Its nonlinear response to high fields requires a new nonlinear calibration technique. A nonlinear calibration method is explained and demonstrated to successfully measure high electric fields, as well as high voltages with dynamic range up to 50 dB. Furthermore, a SCOS can be fitted into narrow spaces and make highly localized measurements due to its small size. This allows a SCOS to be integrated inside a standard high voltage coaxial cable, such as RG-218. Effects of partial discharge and arcing is minimized by development of a fabrication method to avoid introduction of impurities, especially air-bubbles, into the cable during SCOS insertion. Low perturbation of the measured voltage is shown by simulating the introduced voltage reflections to be on the order of –50 dB. It is also shown that a SCOS can be inserted into other cables without significant perturbation to the voltage. A complete high voltage and high electric field measurement system is built based on the high-voltage modifications of the SCOS technology. The coaxial SCOS is enhanced for robustness. Enhancements include packaging a SCOS into stronger ceramic trough, strengthening the fiber with kevlar reinforced furcation tubing and protecting the sensor with metal braces and protective shells. The interrogator is protected from electromagnetic interference with an RF-shielded box. Reduction in power losses introduced by the new PANDA-SCOS technology allows interrogator bandwidths to be increased up to 1.2 GHz. The whole measurement process is streamlined with dedicated software, developed specifically for high voltage and electric field measurements with support for the nonlinear calibration.
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Janoušek, Adam. „Návrh optického vláknového senzoru pro detekci vibrací“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-412994.
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The master theses deals with a detailed analysis of optical fiber sensors. Specifically, there are discussed optical fibers, various types of sensors and realization optical fiber senzor and senzor system that has been optimized and processed data in real time. In master theses also describes the LabView programming enviroment and uses components, including the entire sensor systém of a sensors system that sends measured data
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Buaes, Alexandre Greff. „A low cost one-camera optical tracking system for indoor wide-area augmented and virtual reality environments“. reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/7138.
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O número de aplicações industriais para ambientes de “Realidade Aumentada” (AR) e “Realidade Virtual” (VR) tem crescido de forma significativa nos últimos anos. Sistemas óticos de rastreamento (optical tracking systems) constituem um importante componente dos ambientes de AR/VR. Este trabalho propõe um sistema ótico de rastreamento de baixo custo e com características adequadas para uso profissional. O sistema opera na região espectral do infravermelho para trabalhar com ruído ótico reduzido. Uma câmera de alta velocidade, equipada com filtro para bloqueio da luz visível e com flash infravermelho, transfere imagens de escala de cinza não comprimidas para um PC usual, onde um software de pré-processamento de imagens e o algoritmo PTrack de rastreamento reconhecem um conjunto de marcadores retrorefletivos e extraem a sua posição e orientação em 3D. É feita neste trabalho uma pesquisa abrangente sobre algoritmos de pré-processamento de imagens e de rastreamento. Uma bancada de testes foi construída para a realização de testes de acurácia e precisão. Os resultados mostram que o sistema atinge níveis de exatidão levemente piores, mas ainda comparáveis aos de sistemas profissionais. Devido à sua modularidade, o sistema pode ser expandido através do uso de vários módulos monoculares de rastreamento interligados por um algoritmo de fusão de sensores, de modo a atingir um maior alcance operacional. Uma configuração com dois módulos foi montada e testada, tendo alcançado um desempenho semelhante à configuração de um só módulo.In the last years the number of industrial applications for Augmented Reality (AR) and Virtual Reality (VR) environments has significantly increased. Optical tracking systems are an important component of AR/VR environments. In this work, a low cost optical tracking system with adequate attributes for professional use is proposed. The system works in infrared spectral region to reduce optical noise. A highspeed camera, equipped with daylight blocking filter and infrared flash strobes, transfers uncompressed grayscale images to a regular PC, where image pre-processing software and the PTrack tracking algorithm recognize a set of retro-reflective markers and extract its 3D position and orientation. Included in this work is a comprehensive research on image pre-processing and tracking algorithms. A testbed was built to perform accuracy and precision tests. Results show that the system reaches accuracy and precision levels slightly worse than but still comparable to professional systems. Due to its modularity, the system can be expanded by using several one-camera tracking modules linked by a sensor fusion algorithm, in order to obtain a larger working range. A setup with two modules was built and tested, resulting in performance similar to the stand-alone configuration.
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Selva, Ginani Luciano [Verfasser], René [Akademischer Betreuer] Theska, Eberhard [Akademischer Betreuer] Manske und Hermann [Akademischer Betreuer] Lepikson. „Optical scanning sensor system with submicron resolution / Luciano Selva Ginani. Technische Universität Ilmenau. Gutachter: Eberhard Manske ; Hermann Lepikson. Betreuer: Rene Theska“. Ilmenau : Universitätsbibliothek Ilmenau, 2013. http://d-nb.info/1046916467/34.
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Ashraf, Shahrukh. „Development of a Low-Cost Solution for the Navigation of UAVs in GPS-DeniedEnvironment“. University of Toledo / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1470181376.
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Oliveira, Fatima Cristina de. „Sistema multiespectral portátil para monitoramento de oxigênio dissolvido em meios aquosos e da dinâmica de crescimento microbiano“. Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-27022018-091936/.
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Nos dias de hoje o controle e monitoração de sistemas biológicos relacionados ao controle ambiental tem sido considerado importante para o diagnóstico e biorremediação de sistemas aquosos como rios e lagos. A eficácia dos processos de controle está diretamente relacionada aos processos de medição \"in-situ\" em tempo real. Nesse sentido o presente trabalho apresenta o desenvolvimento de sistemas multiespectrais portáteis para monitoramento, \"in-situ\" e em tempo real, da dinâmica do crescimento microbiano utilizados em processos de biorremediação. Assim, para este fim foram desenvolvidos dois sistemas, um para monitorar a concentração de oxigênio dissolvido (OD) em meio aquoso e outro para monitorar a absorção óptica do meio de cultura. O sensor óptico para monitorar a concentração de OD está baseado em uma fibra óptica na qual em uma de suas pontas (extremidades) foi depositado um filme fino de Poli (cloreto de vinila) (PVC) dopado com moléculas de octaetilporfirina de platina (PtOEP) como parte sensível do dispositivo. O sensor mostrou resposta linear em regiões entre 4 e 18 mg/L de OD em meio aquoso, tendo como tempo de resposta de 8 s e tempo de recuperação de 236 s. O sistema de medida de absorção óptica do meio de cultura foi projetado e fabricado utilizando-se um fotodetector multiespectral e um diodo LED (600nm) como fonte de excitação. A aquisição, controle e processamento de sinais deste sistema está baseado em uma placa de aquisição NI modelo myRIO-1900 fabricado pela National Instruments, utilizando-se tecnologia Field Programmable Gate Array (FPGA). Os resultados obtidos com este sistema mostram ter o mesmo nível de desempenho se comparado ao de um sistema biofotométrico comercial na faixa de concentração entre 1,13 mg/ml à 2,11mg/ml.Nowadays, the controlling and monitoring biological systems related to environmental control has been considered important for the diagnosis and bio-remediation of aqueous systems like rivers and lakes. The effectiveness of this control processes are directly related to \"in-situ\" and real-time measurement processes. In this sense the present work presents the development of portable multispectral systems for monitoring, \"in-situ\" and in real time, the dynamics of microbial growth used in bio-remediation processes. So, for this purpose were fabricated two systems, one to monitor the concentration of dissolved oxygen (DO) in aqueous medium and another to monitor the optical absorption of culture medium. The optical sensor to monitor the DO is based on an optical fiber in which in one of its ends was deposited a poly(vinyl chloride) (PVC) thin film doped with Platinum octaethylphorphyrin molecules (PtOEP) as part of the device. The sensor showed linear response in regions between 4 and 18 mg/L of DO in aqueous medium, with response time of 8s and the recovery time of 236s. The system of measurement of optical absorption of culture medium was designed and manufactured using a multispectral photodetector and a diode LED (600nm) as a source of excitation. The acquisition, signal processing and control of this system are based on an acquisition card NI myRIO-1900 model manufactured by National Instruments, using FPGA technology. The results obtained with this system shows to have the same level of performance to that of a commercial biophotometric system in the concentration range of 1.13 mg/mL to 2.11 mg/mL.
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Dragan, Stupar. „Elektronski sistem za merenje deformacija pri savijanju pomoću polimernog optičkog vlakna sa osetljivom zonom“. Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2016. https://www.cris.uns.ac.rs/record.jsf?recordId=99910&source=NDLTD&language=en.
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U ovoj doktorskoj disertaciji je razvijen elektronski senzorski sistem za merenje deformacija pri savijanju pomoću polimernog optičkog vlakna sa osetljivom zonom. Opisana je metoda izrade fiber-optičkog senzora zakrivljenosti pomoću polimernog optičkog vlakna. Izvršena je simulacija ponašanja senzora i urađena je karakterizacija senzora. Ispitana je mogućnost primene elektronskog senzorskog sistema za detekciju savijanja i loma građevinskih struktura. Pomoću istog senzora je realizovan fiber-optički goniometar za merenje ugla savijanja ljudskog kolena koji karakterišu linearni odziv u opsegu uglova od -45° do 25°, rezolucija od 1° i osetljivost od 20 mV/°. U tezi je takođe data metoda eliminacije grešaka koje mogu nastati usled savijanja delova vlakna koji vode do i od osetljive zone.In this thesis, an electronic system for measurement of bend-induceddeformations by using polymer optical fiber with sensitive zone is developed.A method for fabrication of the fiber-optic curvature sensor by using polymeroptical fiber is described. The simulation and characterization of the sensorbehavior have been conducted. The possibility of application of the proposedelectronic system in structural health monitoring for bending and crackdetection of civil engineering structures is investigated. Also, a fiber-opticgoniometer for human joint movement monitoring characterized by a linearresponse in the range from -45° to 25°, resolution of 1°, and the sensitivity of20 mV/° is implemented. A method for the elimination of errors which may becaused due to bending of lead-in and lead-out sections of the fiber (leadingto and from the sensitive zone) is also described.
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Dikmen, Serkan. „Development of Star Tracker Attitude and Position Determination System for Spacecraft Maneuvering and Docking Facility“. Thesis, Luleå tekniska universitet, Rymdteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-60166.
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Attitude and position determination systems in satellites are absolutely necessary to keep the desired trajectory. A very accurate, reliable and most used sensor for attitude determination is the star tracker, which orient itself in space by observing and comparing star constellations with known star patterns. For on earth tests of movements and docking maneuvers of spacecrafts, the new Spacecraft Maneuvering and Docking (SMD) facility at the chair of Aerospace Information Technology at the University of Würzburg has been built. Air bearing systems on the space ve- hicles help to create micro gravity environment on a smooth surface and simulate an artificial space-like surrounding. A new star tracker based optical sensor for indoor application need to be developed in order to get the attitude and position of the vehicles. The main objective of this thesis is to research on feasible star tracking algorithms for the SMD facility first and later to implement a star detection software framework with new developed voting methods to give the star tracker system its fully autonomous function of attitude determination and position tracking. Furthermore, together with image processing techniques, the software framework is embedded into a controller board. This thesis proposes also a wireless network system for the facility, where all the devices on the vehicles can uniquely communicate within the same network and a devel- opment of a ground station to monitor the star tracker process has also been introduced. Multiple test results with different scenarios on position tracking and attitude determination, discussions and suggestions on improvements complete the entire thesis work.
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Santos, Sofia Raquel Gonçalves dos. „Suspended sediment measurements on laboratory experiments“. Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/17341.
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Mestrado em Engenharia CivilThe sediment transport processes in rivers and coastal zones are characterized by two types of transport: bed-load and suspension. The quantification of this transport is important, in the evaluation of the shoreline and rivers evolution in order to protect areas that could be in danger of erosion when extreme meteorological phenomenon’s happen. How to measure the suspended sediment concentration has been subject of many discussions during the last years. There are several methods to quantify it numerically, although all of them exhibit uncertainties in the results. This work, performed in the Laboratori d’Enginyeria Marítima (LIM) of the Universitat Politècnica de Catalunya (UPC), has as goal to understand why the results obtained from the Optical Backscatter Sensors (OBS) and the Transverse Suction System (TSS) in SINBAD project were distant. To do it, after perform three hundred and twenty nine tests, the experimental and calculation procedures to obtain the best OBS calibration curve were described. Then, the concentrations from OBS and TSS were compared with the real concentrations. In the end, the functionalities of the equipment’s involved in the calibration set-up, OBS applicability and trapping efficiency of TSS, were verified. The results showed that, an accurate fit of OBS data is obtained when the curve is divided in sections depending on the suspended sediment concentration, with different behaviours and fitted differently. This equipment was considered the most accurate, up to concentrations bellow the saturation situation of the sensor.
Os processos de transporte sedimentar nos rios e zonas costeiras caracterizam-se por dois tipos de transporte: pelo fundo ou em suspensão. A quantificação deste transporte é importante, na avaliação da evolução da linha de costa e do leito dos rios, com vista a proteger zonas que possam estar em perigo de erosão na eminência de fenómenos meteorológicos extremos. A medição da concentração de sedimentos em suspensão tem sido, ao longo dos últimos anos, objeto de estudo por vários investigadores. Existem vários métodos para estimar esta grandeza no entanto, ainda apresentam muitas incertezas nos resultados. Esta dissertação, desenvolvida no Laboratório de Engenharia Marítima (LIM) da Universidade Politécnica da Catalunha (UPC), tem como objetivo a verificação do distanciamento dos resultados entre o Optical Backscatter Sensor (OBS) e o Transverse Suction System (TSS) no projeto SINBAD. Para isso, e após realizar 329 testes, foram descritos o procedimento experimental e de cálculo para obter a melhor reta de calibração de um OBS. Seguidamente, as concentrações obtidas com o OBS e com o TSS foram comparadas com as concentrações de sedimentos reais e no final foram verificados parâmetros relacionados com a funcionalidade dos equipamentos utilizados na calibração, a aplicabilidade do OBS e a eficiência do TSS. Os resultados mostraram que, a curva de calibração mais exata de um OBS obtém-se quando os dados são divididos em secções em função da concentração de sedimentos, com diferentes comportamentos, e tratadas separadamente. Este equipamento foi considerado o mais exato, até concentrações em que o sensor não está saturado.
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Le, Guillarme Jonathan, und Jakob Lindstam. „Implementering av Structural Health Monitoring : SHM - system för detektering och övervakning av vanligt förekommande skador på betongbroar“. Thesis, KTH, Byggteknik och design, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-259696.
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Sverige har som många länder runt om i världen en åldrande infrastruktur och behovet av underhåll stiger. I en artikel i Svenska Dagbladet från 21/9–2018 redovisar analys- och teknikkonsultföretaget WSP en grov uppskattning att 300 miljarder kronor behöver investeras för att rusta upp existerande infrastruktur. Efter upprustningen skulle det krävas ca 25 miljarder kronor årligen för att utföra löpande tillståndsbedömning och underhåll av Sveriges väg- och järnvägsnät. Idag används inspektioner för att bedöma broars tillstånd. Det finns tre olika inspektionstyper; huvudinspektion, allmäninspektion och särskild inspektion. Structural Health Monitoring (SHM) är en teknik som globalt används mer och mer som en metod vid tillståndsbedömning av broar. SHM siktar mot att i realtid utföra automatisk bedömning av hela konstruktionens och de enskilda skadornas tillstånd. SHM använder sig av sensorer placerade på kritiska positioner för att samla in mätdata som jämförs med i förtid definierade gränsvärden. I Sverige används SHM sparsamt idag där kunskapen ligger på akademisk nivå och det råder en osäkerhet om hur SHM ska implementeras i praktiken. Genom att implementera SHM, kan skador upptäckas i ett tidigt skede och minimeras genom att snabbt utföra reparationer på konstruktionen innan skadorna blivit kritiska. Studien syftar till att producera en rapport som kan användas som en guide för hur SHM kan implementeras samt visa på hur SHM-systemen har implementerats på tidigare projekt. Rapporten skall ge läsaren en helhetsbild över hur tillståndsbedömning går till idag, vilka skador som är vanligt förekommande samt hur SHM kan användas som ett verktyg vid tillståndsbedömning. Rapporten syftar också till att ge en övergripande förklaring på svenska av SHM-tekniken och vad som behövs för implementering. Öppna ostrukturerade intervjuer genomfördes med forskare inom SHM och skador på betongkonstruktioner samt sakkunniga inom tillståndsbedömning. Intervjuerna användes som utgångspunkt för vidare studier av vanligt förekommande skador och SHM-tekniker. I litteraturstudien användes olika vetenskapliga databaser såsom Diva och ScienceDirect, samt KTH:s bibliotek för att få fram tidigare material om betongskador på broar, deras skademekanismer och om SHM-tekniken. Vidare hämtades information från ett antal doktorsavhandlingar, artiklar och tidigare examensarbeten. Genom litteraturstudie och intervjuer med sakkunniga kom studien fram till att armeringskorrosion och sprickor i betongen är skador som är vanligt förekommande i betongbroar. Skadornas skademekanismer beskrivs i rapporten. Studien identifierade tre olika system som kan användas för detektering och övervakning av armeringskorrosion och sprickor, de systemen är akustisk emission, SOFO-system (SOFO är en förkortning för Surveillance d'Ouvrage par Fibers Optics) och MuST-system (MuST är ett kommersiellt namn). Rapporten ger exempel på hur systemen kan användas för detektering och övervakning av skadorna genom att presentera fyra fallstudier där systemen har använts. Två av fallstudierna presenterar hur akustisk emission har implementeras och två av fallstudierna presenterar hur SOFO-systemet har implementerats. Studien kunde inte identifiera någon fallstudie för MuST-systemet och hur systemet har implementerats. Slutsatsen av studien är att SHM kan användas som ett komplement vid tillståndsbedömningar men man kan inte utföra automatiserade tillståndsbedömningar idag.Like many countries around the world, Sweden has an aging infrastructure and the need for maintenance is increasing. In an article in Svenska Dagbladet from 21 / 9–2018, the analysis and engineering consulting company WSP reports a rough estimate that SEK 300 billion needs to be invested to upgrade existing infrastructure. After the upgrade, it would require approximately SEK 25 billion annually to carry out ongoing condition assessment and maintenance of Sweden's road and railway networks. Today, inspections are used to assess the condition of bridges. There are three types of inspection; main inspection, general inspection and special inspection. Structural Health Monitoring (SHM) is a technology that is globally more used as a method for condition assessment of bridges. SHM aims to perform automatic assessment of the state of the entire construction and individual damages in real time. SHM uses sensors placed at critical positions to collect measurement data compared to pre-defined limit values. In Sweden, SHM is used sparingly today, where knowledge is at an academic level and there is uncertainty about how SHM should be implemented in practice. By implementing SHM, damage can be detected at an early stage and minimized by quickly performing repairs on the design before the damage becomes critical. The study aims to produce a report that can be used as a guide on how SHM can be implemented and show how the SHM systems have been implemented on previous projects. The report should give the reader an overall picture of how condition assessment is performed today, which damages are common and how SHM can be used as a tool when assessing the condition. The report also aims to provide an overall explanation in Swedish of the SHM technology and what is needed for implementation. Open unstructured interviews were conducted with researchers within SHM and damages to concrete structures as well as experts in condition assessment. The interviews were used as a starting point for further studies of commonly occurring damages and SHM techniques. In the literature study, various scientific databases were used, such as Diva and ScienceDirect, as well as KTH's library to obtain earlier material on concrete damage to bridges, its damage mechanisms and about SHM technology. Furthermore, information was obtained from a number of doctoral dissertations, articles and previous degree projects. Through literature study and interviews with experts, the study concluded that reinforcement corrosion and cracks in the concrete are damages that are commonly found in concrete bridges. The damage mechanisms are described in the report. The study identified three different systems that can be used for detection and monitoring of reinforcement corrosion and cracks, those systems are acoustic emission, SOFO system (SOFO is an abbreviation for Surveillance d'Ouvrage pair of Fiber's Optics) and MuST system (MuST is a commercial name). The report gives examples of how the systems can be used for the detection and monitoring of the damages by presenting four case studies where the systems have been used. Two of the case studies present how acoustic emission has been implemented and two of the case studies present how the SOFO-system has been implemented. The study could not identify any case study for the MuST-system and how the system was implemented. The conclusion of the study is that SHM can be used as a supplement to condition assessments but cannot for the time being used for performing automated condition assessments today.
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Wang, Dong Ning. „White light interferometric sensor systems“. Thesis, City University London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283188.
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Ludden, Brendan Patrick. „A distributed optical fibre sensor“. Thesis, University of Cambridge, 1997. https://www.repository.cam.ac.uk/handle/1810/272327.
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Miller, Mark S. „Optical fiber-based corrosion sensor systems“. Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-03042009-041455/.
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Crosby, Peter. „In-situ cure monitoring of epoxy resin systems“. Thesis, Brunel University, 1998. http://bura.brunel.ac.uk/handle/2438/5425.
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This thesis describes the work carried out at Brunel University to develop novel optical fibre sensors capable of monitoring the cure state of an epoxy/amine resin system. The sensors were of simple construction, consisting of an optical fibre from which the silicone cladding layer had been removed over a short length. This stripped length was embedded into the curing resin system. The sensor was successfully used in two ways: i) as an evanescent absorption sensor to monitor specific absorption bands of the resin system. The absorption of energy from the evanescent wave of the optical fibre by absorbing media allows evanescent absorption spectra to be obtained. Absorption spectra were obtained from sensors embedded in a model curing resin system over narrow wavelength ranges. These wavelength ranges corresponded to positions of known absorptions in the spectra of active components in epoxy/amine systems. By monitoring the change in these absorptions it was possible to obtain information about concentration of the amine hardener functional group throughout cure; ii) as a refractive index sensor capable of monitoring the changes in the refractive index of the resin system during cure. A laser diode was used to launch light into the sensor and the intensity of light emerging from the other end of the fibre was monitored. Changes in the resin system refractive index caused changes in the guiding properties of this the sensor. This resulted in a significant change in the intensity of light recorded by the detector and allowed the cure process to be followed. This sensor was also embedded into a unidirectional pre-preg system and was able to follow the cure of the system. The results from the two sensing methods have been compared with data obtained using FTIR spectroscopy and Abbe refractometry during the resin system cure. A theoretical model of sensor response has been developed and compared with the experimental data obtained. The sensor response has also been compared to predictions made by several models of evanescent sensor systems obtained from the literature. These models have been modified so that they can be applied to a sensor embedded into a curing resin system. An analysis of the correspondence between theory and experiment is presented.
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Talebi, Fard Sahba. „Optical resonator sensors and systems“. Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52834.
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Silicon-on-insulator (SOI)-based sensors are attractive for sensing applications in environmental safety, oil and gas, medical research, and clinical applications. Since these devices are typically developed using Complementary metal-oxide-semiconductor (CMOS)-compatible multi-project-wafer (MPW) shuttles, they bring the potential for having sensing systems on chips (SSOCs), and for mass fabrication and low cost production. The objective of this thesis is to improve the sensitivity, accuracy, and repeatability of sensors fabricated on the SOI platform. Such sensors have the potential to be the key components of an SSOC.
One can increase the sensitivity of a resonator sensor by increasing the interaction between the evanescent field of the guided mode and the analyte. In this thesis, two methods for increasing this interaction in micro-ring resonator-based sensors are investigated: 1) using the transverse electric (TE) guided mode in ultra-thin strip waveguides and 2) using the quasi-transverse magnetic (TM) guided mode in thin strip waveguides. Using analyses and simulations, micro-ring sensors were designed to be fabricated within the constraints of a MPW CMOS-compatible process. Using the TE sensors, the temperature-induced errors were reduced by a factor of three; and the TM sensors exhibited twice the sensitivity of the best SOI micro-ring resonator-based sensors reported to date.
Moving towards the actual implementation of an SSOC, a system of sensors was design to correct for unwanted variations in the measurements. This system drew on multivariate techniques to achieve improvements that resulted in measurements that were more repeatable and more accurate in the presence of environmental variations. The capability of this system is investigated by designing a cascade of previously developed micro-ring sensors with various waveguide thicknesses. With this system of sensors, we achieved an R2 value of predictions over 0.996 in the presence of a 2 K temperature drift. This approach significantly improved the repeatability and reliability of the measurements in the presence of undesirable variations and drifts. In another move towards achieving an SSOC, integrating photodetectors in resonator sensors was investigated. To accomplish this, ion-implantation on micro-ring sensors was used. Such integrated photodetector-sensors were designed, fabricated, and tested. Their measured sensitivities were within 90% of the expected values.Applied Science, Faculty of
Graduate
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Kahn, Mohammed Tariq Ekeramodien. „Miniaturised dedicated application opto-electronic sensors in the evolution of smart systems“. Thesis, Peninsula Technikon, 2002. http://hdl.handle.net/20.500.11838/1196.
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Thesis (DTech (Electrical Engineering))--Peninsula Technikon, Cape Town, 2002In the last decade, the South Amcan Electricity Supply Commission would have had their ability to serve an ever demanding public severely tested. With the dilemma of providing electricity supply through hazardous environmental conditions, and with prospects of supplying power even beyond South Afiican borders, the need for a comprehensive damage and power delivery assessment strategy becomes all the more relevant. The rapid growth being made in the evolution of so called "intelligent" structures, with inherent sensor, actuator and control mechanisms built in can have direct influence on a power distribution network. At least in the foreseeable future, the impact ofphotonic sensors with inherent miniaturization, a foremost candidate in Smart System technology, can play a vital role in damage assessment of a potentially large network such as that found in the supply ofelectricity. Smart systems are nonliving systems that integrate the functions of sensing, actuation, logic and control, to respond adaptively to changes in their condition or environment to which they are exposed, in a useful and usually repetitive manner. Sensors are a fundamental part of the evolution of such systems and form the basis for the topic of this dissertation. The use ofoptical fiber sensors is increasing widely mainly due to their (a) miniature size, (b) remote signal processing ability, and (c) multiplexing capabilities. Because of the above features a variety of optical fiber sensing techniques has evolved over the years having potential for a myriad of applications. In this work a systems model and equations was developed for modeling the propagation of light in a optical waveguide, in order to study a Fabry Perrot sensor topology for application as a miniaturised sensor in a new type of smart structure, namely a smart electrical power system.
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Barragan, Dante E. „Optimal placement of sensors for network lifetime extension in wireless sensor networks with dynamic routing“. To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Mason, Julian. „Guided-wave optical and hybrid sensor systems“. Thesis, Kingston University, 1995. http://eprints.kingston.ac.uk/20587/.
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This thesis is concerned with the development of new fibre optic based sensors for liquid level and temperature measurement. For the measurement of fluid level an intrinsic sensor has been developed whereby the fibre itself forms the sensing medium. This fibre is made from a plastic, doped with a dye that fluoresces when illuminated by ultra-violet light. The sensing fibre is continuously illuminated but the fluid around it absorbs the light and hence the fluid level controls the intensity of light generated within the fluorescing fibre. The measurement of temperature forms the bulk of this thesis with liquid crystals being used as the transducing medium. Many different schemes have been investigated and characterised using their thermochromic, light scattering, and electro-optic properties. The latter necessitated the production of miniature photovoltaic devices which, apart from being a novel way of generating quasi-regulated electrical power, provide an alternative approach to energising many other types of hybrid sensor systems that at present are forced to use more complex techniques. Finally a simple theory has been developed to describe the behaviour of the liquid crystal based systems. The theory has been solved numerically and is in good agreement with the experimental results.
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Neradilková, Aneta. „Inspekční objektový senzor“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316825.
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Object inspection sensor is a device that is mainly used in the automation of the production process. The Diploma Thesis deals with the familiarization of optical inspection systems, survey and comparison of companies of these systems in the Czech Republic. ELLA-CS company and dafault state output control products in her workplace is presented in the Diploma Thesis. The next part concerns the design of the inspection system for the company ELLA-CS, which is designed on the platform Raspberry. The thesis also deals with the implementation of the inspection system, which describes the hardware and software of this system. The last part is intended to discuss the results and suggestions for improving the inspection.
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Luna, Arriaga Antonio. „Analysis and implementation of algorithms for embedded self-mixing displacement sensors design“. Phd thesis, Toulouse, INPT, 2014. http://oatao.univ-toulouse.fr/11920/1/luna_arriaga.pdf.
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Henderson, Philip James. „Chromatic modulation systems for multiparameter measurement in physically demanding environments“. Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257163.
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Willshire, Andrew J. „Robust optical sensor systems for aero-engine monitoring“. Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423883.
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Graumann, Jean-Marc. „Intelligent optical methods in image analysis for human detection“. Thesis, Brunel University, 2005. http://bura.brunel.ac.uk/handle/2438/7892.
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This thesis introduces the concept of a person recognition system for use on an integrated autonomous surveillance camera. Developed to enable generic surveillance tasks without the need for complex setup procedures nor operator assistance, this is achieved through the novel use of a simple dynamic noise reduction and object detection algorithm requiring no previous knowledge of the installation environment and without any need to train the system to its installation. The combination of this initial processing stage with a novel hybrid neural network structure composed of a SOM mapper and an MLP classifier using a combination of common and individual input data lines has enabled the development of a reliable detection process, capable of dealing with both noisy environments and partial occlusion of valid targets. With a final correct classification rate of 94% on a single image analysis, this provides a huge step forwards as compared to the reported 97% failure rate of standard camera surveillance systems.
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Khan, Muneeb Ullah. „Contribution to the design and fabrication of an integrated micro-positioning system“. Thesis, Compiègne, 2014. http://www.theses.fr/2014COMP1671/document.
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L’objectif de la thèse est de développer un dispositif de micro positionnement intégrant à la fois les actionneurs et les capteurs. Un dispositif a été conçu afin de réaliser des déplacements dans les plans sur une course millimétrique. Le dispositif compact ne nécessite pas de système de guidage additionnel et selon le mode d’utilisation de ces moteurs, il est capable de réaliser des translations dans le plan ou des rotations autour d’un axe perpendiculaire au plan. Le dispositif comprend quatre moteurs électromagnétiques linéaires fixés orthogonalement sur une structure en forme de croix. Chaque moteur consiste en une paire de bobines planes entrelacées fixe et une barre ’aimants mobile. Un capteur de déplacement intégré dans la structure en croix permettant de mesurer le déplacement de celle-ci a été conçu et fabriqué. Ce capteur est constitué d’une tête de mesure à fibres optiques placé face à un réseau en silicium réalisé par des techniques de microfabrication. Afin de minimiser les erreurs d’assemblage, la structure en croix a également été micro fabriquée. Le dispositif est capable de réaliser un déplacement de 10 mm et une rotation de ±11° autour de l’axe perpendiculaire au plan du dispositif. La résolution de déplacement du dispositif est de 1,4 µm avec une précision de 31 nm en boucle fermée. Le dispositif peut également atteindre une vitesse de déplacement de 12 mm/sThe objective of thesis is to develop an integrated micro positioning system for micro applications. A unique micro positioning system design capable to deliver millimeter level strokes with pre-embedded auto guidance feature in micro application has been realized. The design integrates, a stack of orthogonally arranged four electromagnetic linear motors. Each linear motor consists of a fixed planar electric drive coil and mobile permanent magnet array. The optimal design of the system delivers a small footprint size. In addition, to measure and control the displacement, a high resolution compact optical displacement measurement sensor has been designed and fabricated in silicon material using microfabrication technology. Furthermore, a light weight silicon cross structure was fabricated using dry etching technology to reduce components assembly errors. The device is capable to deliver 10 mm displacement stroke with a rotation of ±11° about an axis perpendicular to the plane of the device. The displacement resolution of the device is 1.4 µm with a precision of 31 nm in closed loop control. The device can realize displacement with a speed of 12 mm/s
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Godfrey, Martin William. „Optical detection system for ultrasonic surface displacements“. Thesis, Loughborough University, 1986. https://dspace.lboro.ac.uk/2134/28001.
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The work was carried out with the aim of developing an optical interferometric detection system. This was to be applied to the quantative measurement of low amplitude, high frequency surface displacements (< 1nm at several MHz). Two forms of interferometric detector are investigated. The performance and limitations in particular measurement situations are assessed for both types of interferometer. The first type of detector investigated is a miniature stabilised interferometer. The design of a stabilisation system is given, along with ways in which it can be optimised for a particular environment. The second type of detector studied is a quadrature interferometer. Various methods of processing the two channels of information from this device are discussed. The design of a new method of processing the signals is given, and its performance determined. The interferometric sensor is combined with a waveform digitiser and microcomputer to form an integrated detection system. Analysis of the waveforms obtained is performed by a system of Pascal programs developed for this purpose. The detection system is applied to tasks such as the calibration of other forms of transducer and the characterisation of artificial sources of acoustic emission. The results of experimental studies are given and the applications of such a system discussed.
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Montagner, Elison. „Optical readout system for bi-material terahertz sensors“. Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5478.
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Approved for public release; distribution is unlimited.The objective of this work is to design, assemble, and characterize an optical readout for bi-material MEMs sensor arrays that can be integrated into a THz imaging system. All this effort is a contribution to the goals of the research conducted by the Naval Postgraduate School Sensor Research Laboratory on designing and fabricating THz-optimized bi-material MEMs sensor arrays for THz imaging. Basic concepts of THz radiation and detection are presented. Several aspects of THz imaging, and sensor's array readout possibilities, are discussed in terms of the principle of operation for this type of sensor. An experimental optical readout was assembled during this research, and its configuration is shown, as well as all of its component details. The experimental setup was characterized following a method described in this work, and the obtained results are analyzed. Finally, one possibility of optical readout integration with a THz imaging system is suggested.
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Glomon, Lhusak. „Source based chromatic methodology for optical fibre sensor systems“. Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400231.
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Wang, Qi. „Studies of multimode fibre linked white light interferometric sensor systems“. Thesis, City University London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389649.
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Lewin, A. C. „An investigation of optical fibre interferometric vibration and rotation measurement techniques“. Thesis, University of Kent, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383750.
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Hofmann, Oliver. „Microfluidic systems for rapid immunoassays“. Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249705.
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Santos, Figueroa Luis Enrique. „New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest“. Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/43216.
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El presente proyecto de investigación está enfocado al desarrollo de sensores químicos fluoro-cromogénicos, para la detección y determinación de especies químicas de interés biológico, industrial y medioambiental de forma selectiva y con alta sensibilidad.
En forma general, se busca el diseñar nuevos sistemas sensores basados en compuestos (receptores) formados por dos unidades: una unidad coordinante que interacciona con el anión a determinar y una unidad generadora de señal que alerta del reconocimiento molecular efectuado.
Durante este estudio se están preparando diversas moléculas receptoras funcionalizandas con grupos modificadores de estructura para evaluar su influencia sobre las capacidades de detección y selectividad como receptores de especies específicas en diferentes condiciones y medios.
Las diferentes aproximaciones en prueba implican a su vez el diseño y síntesis molecular, así como el análisis de las diferentes señales ópticas producidas en el reconocimiento, con el fin de diseñar sistemas de alta eficacia y eficiencia, y con posibilidades reales de aplicación.Santos Figueroa, LE. (2014). New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/43216
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