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Vision based control and landing of Micro aerial vehicles / Visionsbaserad styrning och landning av drönareKarlsson, Christoffer January 2019 (has links)
This bachelors thesis presents a vision based control system for the quadrotor aerial vehicle,Crazy ie 2.0, developed by Bitcraze AB. The main goal of this thesis is to design andimplement an o-board control system based on visual input, in order to control the positionand orientation of the vehicle with respect to a single ducial marker. By integrating a cameraand wireless video transmitter onto the MAV platform, we are able to achieve autonomousnavigation and landing in relatively close proximity to the dedicated target location.The control system was developed in the programming language Python and all processing ofthe vision-data take place on an o-board computer. This thesis describes the methods usedfor developing and implementing the control system and a number of experiments have beencarried out in order to determine the performance of the overall vision control system. Withthe proposed method of using ducial markers for calculating the control demands for thequadrotor, we are able to achieve autonomous targeted landing within a radius of 10centimetres away from the target location. / I detta examensarbete presenteras ett visionsbaserat kontrollsystem for dronaren Crazy ie 2.0som har utvecklats av Bitcraze AB. Malet med detta arbete ar att utforma och implementeraett externt kontrollsystem baserat pa data som inhamtas av en kamera for att reglera fordonetsposition och riktning med avseende pa en markor placerad i synfaltet av kameran. Genom attintegrera kameran tillsammans med en tradlos videosandare pa plattformen, visar vi i dennaavhandling att det ar mojligt att astadkomma autonom navigering och landning i narheten avmarkoren.Kontrollsystemet utvecklades i programmeringsspraket Python och all processering avvisions-datan sker pa en extern dator. Metoderna som anvands for att utvecklakontrollsystemet och som beskrivs i denna rapport har testats under ett ertal experiment somvisar pa hur val systemet kan detektera markoren och hur val de olika ingaendekomponenterna samspelar for att kunna utfora den autonoma styrningen. Genom den metodsom presenteras i den har rapporten for att berakna styrsignalerna till dronaren med hjalp avvisuell data, visar vi att det ar mojligt att astadkomma autonom styrning och landning motmalet inom en radie av 10 centimeter.
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A Novel Approach for Spherical Stereo Vision / Ein Neuer Ansatz für Sphärisches Stereo VisionFindeisen, Michel 27 April 2015 (has links) (PDF)
The Professorship of Digital Signal Processing and Circuit Technology of Chemnitz University of Technology conducts research in the field of three-dimensional space measurement with optical sensors. In recent years this field has made major progress.
For example innovative, active techniques such as the “structured light“-principle are able to measure even homogeneous surfaces and find its way into the consumer electronic market in terms of Microsoft’s Kinect® at the present time. Furthermore, high-resolution optical sensors establish powerful, passive stereo vision systems in the field of indoor surveillance. Thereby they induce new application domains such as security and assistance systems for domestic environments.
However, the constraint field of view can be still considered as an essential characteristic of all these technologies. For instance, in order to measure a volume in size of a living space, two to three deployed 3D sensors have to be applied nowadays. This is due to the fact that the commonly utilized perspective projection principle constrains the visible area to a field of view of approximately 120°. On the contrary, novel fish-eye lenses allow the realization of omnidirectional projection models. Therewith, the visible field of view can be enlarged up to more than 180°. In combination with a 3D measurement approach, thus, the number of required sensors for entire room coverage can be reduced considerably.
Motivated by the requirements of the field of indoor surveillance, the present work focuses on the combination of the established stereo vision principle and omnidirectional projection methods. The entire 3D measurement of a living space by means of one single sensor can be considered as major objective.
As a starting point for this thesis chapter 1 discusses the underlying requirement, referring to various relevant fields of application. Based on this, the distinct purpose for the present work is stated.
The necessary mathematical foundations of computer vision are reflected in Chapter 2 subsequently. Based on the geometry of the optical imaging process, the projection characteristics of relevant principles are discussed and a generic method for modeling fish-eye cameras is selected.
Chapter 3 deals with the extraction of depth information using classical (perceptively imaging) binocular stereo vision configurations. In addition to a complete recap of the processing chain, especially occurring measurement uncertainties are investigated.
In the following, Chapter 4 addresses special methods to convert different projection models. The example of mapping an omnidirectional to a perspective projection is employed, in order to develop a method for accelerating this process and, hereby, for reducing the computational load associated therewith. Any errors that occur, as well as the necessary adjustment of image resolution, are an integral part of the investigation. As a practical example, an application for person tracking is utilized in order to demonstrate to which extend the usage of “virtual views“ can increase the recognition rate for people detectors in the context of omnidirectional monitoring.
Subsequently, an extensive search with respect to omnidirectional imaging stereo vision techniques is conducted in chapter 5. It turns out that the complete 3D capture of a room is achievable by the generation of a hemispherical depth map. Therefore, three cameras have to be combined in order to form a trinocular stereo vision system. As a basis for further research, a known trinocular stereo vision method is selected. Furthermore, it is hypothesized that, applying a modified geometric constellation of cameras, more precisely in the form of an equilateral triangle, and using an alternative method to determine the depth map, the performance can be increased considerably. A novel method is presented, which shall require fewer operations to calculate the distance information and which is to avoid a computational costly step for depth map fusion as necessary in the comparative method.
In order to evaluate the presented approach as well as the hypotheses, a hemispherical depth map is generated in Chapter 6 by means of the new method. Simulation results, based on artificially generated 3D space information and realistic system parameters, are presented and subjected to a subsequent error estimate.
A demonstrator for generating real measurement information is introduced in Chapter 7. In addition, the methods that are applied for calibrating the system intrinsically as well as extrinsically are explained. It turns out that the calibration procedure utilized cannot estimate the extrinsic parameters sufficiently. Initial measurements present a hemispherical depth map and thus con.rm the operativeness of the concept, but also identify the drawbacks of the calibration used. The current implementation of the algorithm shows almost real-time behaviour.
Finally, Chapter 8 summarizes the results obtained along the studies and discusses them in the context of comparable binocular and trinocular stereo vision approaches. For example the results of the simulations carried out produced a saving of up to 30% in terms of stereo correspondence operations in comparison with a referred trinocular method. Furthermore, the concept introduced allows the avoidance of a weighted averaging step for depth map fusion based on precision values that have to be calculated costly. The achievable accuracy is still comparable for both trinocular approaches.
In summary, it can be stated that, in the context of the present thesis, a measurement system has been developed, which has great potential for future application fields in industry, security in public spaces as well as home environments.
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Undersökning av kostnader som uppstår vid tillverkning av flera produktvarianter : En studie utförd på Axis Communications / Analysis of arising costs related to the manufacturing of multiple product variants : A study performed at Axis CommunicationsPersson, Jesper, Persson, Johanna January 2017 (has links)
Dagens företag lägger ner allt mer tid och resurser på att utöka variantfloran i deras produktsortiment. Syftet är att nå ut till ett bredare segment av kunder samtidigt som företaget behåller en konkurrenskraftig position på marknaden. Vid framtagning av nya produkter ställs Axis Communications ofta inför utmaningen att ta beslut om att tillverka en eller flera varianter. I dagsläget tas beslut om att tillverka fler varianter i produktsortimentet utifrån priset på direkt material och försäljningsvolymen för varje variant. Axis Communications saknar därmed kunskap om vilka ytterligare faktorer som påverkas när beslut om variantskapande ska tas. Syftet med studien är att ta fram en beräkningsmodell som kan användas som beslutsunderlag vid analys av kostnader i att tillverka mer än en produktvariant. För att besvara syftet har studien genomfört två fallstudier utifrån två olika produkter i Axis Communications produktsortiment. Den första fallstudien analyserar nuläget av tillverkningen hos Axis Communications kontraktstillverkare där kostnader som påverkas av att flera varianter tillverkas identifieras och beräknas. Den andra fallstudien är en fiktivt fallstudie där de identifierade kostnaderna beräknas på nytt men då endast en variant tillverkas och resterande varianter tagits bort. Därefter utfördes en analys på hur de identifierade kostnaderna påverkas vid tillverkning av endast en variant. Utifrån litteraturstudier har de kostnader som påverkas i samband med att flera varianter tillverkas identifierats. Vidare har även processkartläggningar samt ett studiebesök hos en av Axis Communications kontraktstillverkare genomförts där ytterligare relevanta kostnader identifierats och bekräftats av personer med bred kunskap inom området. De kostnader som identifierats i studien och som därmed ansett påverkas mest av att variantfloran förändras är följande: Direkta särkostnader Direkt material Lagerföringskostnader Ställkostnader Fixtur- och verktygskostnader Indirekta särkostnader Kvalitetskostnader Time to Market Investeringskostnader Resurskostnader för utveckling av mekanik Resurskostnader för utvecklig av elektronik Certifieringskostnader Verktygskostnader Kostnader för test av produktion Kostnader för framtagning av prototyper Resultatet för direkt material visade att det går att utgå från ett medelvärde av priset för direkt material samt den prognostiserade försäljningsvolymen per variant för att skapa sig en första uppfattning om hur mycket variantskapande egentligen kostar. Lagerföringskostnaden visade sig också påverkas vid tillverkning av endast en variant. Lagerföringskostnaden minskade i lagret för komponenter men ökade samtidigt i färdigvarulagret eftersom att det endast är den dyrare varianten med avseende på direkt material som tillverkas då det är den variant som har samtliga funktioner jämfört med resterande varianter. Ställkostnaden eliminerades helt då ställtiderna som uppstår vid byte av varianter i tillverkningen försvann. Vidare så halverades kostnaderna för fixturer och verktyg. Kvalitetskostnaden visade sig vara svårare att kvantifiera, dock gick det att inse att desto högre volym som tillverkas av en variant desto fortare når varianten de uppsatta kvalitetsmålen vilket i sin tur bidrar till lägre kvalitetskostnader. Dessutom innebär ett lägre antal varianter i en och samma produktionslina att hanteringen blir lättare då bland annat risken för felmontering minskar. Det blir även lättare att identifiera, prioritera samt åtgärda fel som kan tänkas uppstå i produktionslinan. Det leder i sin tur till att kvalitetskostnaderna minskar. Time to Market påverkades också när endast en variant tillverkades. Även om Time to Market inte direkt kan ses som en kostnad utan snarare som ett intäktsbortfall, påvisade studien att det går fortare att få fram produkterna på marknaden om antalet varianter minskar. Slutligen studerades olika investeringskostnader som går att koppla till tillverkningen av flera varianter och resultatet visade på att det går att minska investeringskostnaderna om endast en variant tillverkas. Utifrån resultatet från de två fallstudierna utformades en beräkningsmodell åt Axis Communications som ska hjälpa företaget med att ta beslut om variantskapande. Beräkningsmodellen lyfter fram de kostnader som påverkas mest av en förändring i variantfloran tillsammans med en beskrivning av hur kostnaderna ska beräknas. Med hjälp av beräkningsmodellen kan Axis Communications beslut om variantskapande underlättas jämfört med hur de tar beslut idag. / Today’s companies spend a significant amount of time and resources on increasing the number of product variants in their product range. The aim is to reach a wider segment of customers while maintaining a competitive position in the market. When developing new products, Axis Communications is often faced with the challenge of deciding whether to focus on one or more product variants. At present, focus is directed towards developing more product variants in the product range based on the price of direct material and the sales volume for each variant. Axis Communications therefore lacks knowledge of what additional factors that are affected when decisions about creating more product variants are taken. The purpose of the study is to provide a calculation model that can be used as a basis for analysing costs in producing more than one product variant. In order to achieve this purpose, the study has carried out two case studies based on two different products in Axis Communications product range. The first case study analyses the current state of production at Axis Communications’ contracted manufacturers, where costs that are affected by the production of multiple variants are identified and calculated. The second case study is a fictitious case study where the identified costs are calculated again, but only when one product variant is manufactured and the remaining product variants are disregarded. This was followed by an analysis regarding how the identified costs are affected when only one product variant is manufactured. Based on literature studies, the costs associated with the production of several variants have been identified. Furthermore, process flow charts have been developed and a study visit to one of Axis Communications contracted manufacturers was undertaken, where additional relevant costs have been identified and confirmed by persons with broad knowledge about the manufacturing processes. The costs identified to be affected the most by the variation of product variants are as follows: Direct incremental costs Direct material Inventory carrying costs Setup costs Fixture- and tooling costs Indirect incremental costs Quality costs Time to Market Investment costs Resource costs for the development of mechanics Resource costs for the development of electronics Certification costs Tooling costs Costs for testing of production Costs for prototyping The result for direct material showed that an average of the price of direct material as well as the forecasted production volume for each product variant can be assumed to create an initial perception of how much an increase of product variants actually costs. The inventory carrying cost also proved affected by the manufacturing of only one product variant. The inventory carrying cost decreased in the inventory of components but increased at the same time in the finished goods inventory since it is only the most expensive product variant with all functions compared to the other product variants that is being stored. The setup cost was eliminated since the setup times that occurred when changing product variants in the production disappeared. Furthermore, the cost of fixtures and tools was halved. The quality cost proved to be harder to quantify, however, it was realized that the higher the volume produced by a product variant the faster the product variant reaches the set quality goals, which in turn contributes to lower quality costs. Additionally, a lower number of product variants in the same production line means that handling becomes easier, including the risk of errors in assembling the product variant. It will also be easier to identify, prioritize and correct errors that may occur in the production line. This in turn leads to a reduction of quality costs. Time to Market was also affected when only one product variant was manufactured. Although Time to Market cannot be seen directly as a cost but rather as a loss of revenue, the study showed that it is faster to launch the product on the market if the number of product variants decreases. Finally, various investment costs were studied that could be linked to the production of several product variants, and the result showed that it is possible to reduce the investment costs if only one product variant is manufactured. Based on the outcome of the two case studies, a calculation model was designed for Axis Communications to help the company decide whether to manufacture product variants or not. The calculation model explains the costs that are affected the most by a change of number of product variants together with a description of how the costs are to be calculated. Using the calculation model will enable Axis Communications to make well-informed decision on whether or not to introduce more product variants in the product range.
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Využití kvalitativního a kvantitativního výzkumu pro tvorbu následné marketingové strategie u tištěných medií / Aplication of quality and quantity data outputs of research to be used for follow up marketing strategy in print mediasHofmannová, Vlasta January 2008 (has links)
Diploma thesis entitled "Application of Qualitative and Quantitative Research Methods into Marketing Strategy of Print Medias" discusses employment of output research data accumulated on eye-tracking, in-depth interviewing and CAWI method of research. These research outcomes are further analyzed and implemented in the development process of the EURO Business Weekly strategy in the Czech publishing market. The final evaluation is based on a mutual comparison of results which were recorded by the EURO Business Weekly in the years 2005 and 2006.
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Optický radar s využitím dvouosého kamerového manipulátoru / Optical Localization System with a Pan/Tilt CameraSenčuch, Daniel January 2018 (has links)
The effective surveillance of large critical areas is crucial for their security and privacy. There is no publicly available and acceptable solution of automating this task. This thesis aims to create an application utilizing a combination of a pan-tilt robotic manipulator and a visible-spectrum camera. Based on the pan-tilt unit's position and camera's images, the application searches for semantically significant changes in the captured environment and marks these regions of interest.
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Detekce vad vláknitého materiálu užitím metod strojového učení / Defect detection on fiber materials using machine learningLang, Matěj January 2019 (has links)
Cílem této diplomové práce je automatizace detekce vad ve vláknitých materiálech. Firma SILON se již přes padesát let zabývá výrobou jemné vaty z recyklovaných PET lahví. Tato vata se následně používá ve stavebnictví, automobilovém průmyslu, ale nejčastěji v dámských hygienických potřebách a dětských plenách. Cílem firmy je produkovat co nejkvalitnější výrobek a proto je každá dávka testována v laboratoři s několika přísnými kritérii. Jednám z testů je i množství vadných vláken, jako jsou zacuchané smotky vláken, nebo nevydloužená vlákna, která jsou tvrdá a snadno se lámou. Navrhovaný systém sestává ze snímací lavice fungující jako scanner, která nasnímá vzorek vláken, který byl vložen mezi dvě skleněné desky. Byla provedena série testů s různým osvětlením, která ověřovala vlastnosti Rhodaminu, který se používá právě na rozlišení defektů od ostatních vláken. Tyto defekty mají zpravidla jinou molekulární strukturu, na kterou se barvivo chytá lépe. Protože je Rhodamin fluorescenční barvivo, je možné ho například pod UV světlem snáze rozeznat. Tento postup je využíván při manuální detekci. Při snímání kamerou je možno si vypomoci filtrem na kameře, který odfiltruje excitační světlo a propustí pouze světlo vyzářené Rhodaminem. Součástí výroby skeneru byla i tvorba ovládacího programu. Byla vytvořena vlastní knihovna pro ovládání motoru a byla upravena knihovna pro kameru. Oba systém pak bylo možno ovládat pomocí jednotného GUI, které zajišťovalo pořizování snímku celé desky. Pomocí skeneru byla nasnímána řada snímků, které bylo třeba anotovat, aby bylo možné naučit počítač rozlišovat defekty. Anotace proběhla na pixelové úrovni; každý defekt byl označen v grafickém editoru ve speciální vrstvě. Pro rozlišování byla použita umělá neuronová síť, která funguje na principu konvolucí. Tento typ sítě je navíc plně konvoluční, takže výstupem sítě je obraz, který by měl označit na tom původním vadné pixely. Výsledky naučené sítě jsou v práci prezentovány a diskutovány. Síť byla schopna se naučit rozeznávat většinu defektů a spolehlivě je umí rozeznat a segmentovat. Potíže má v současné době s detekcí rozmazaných defektů na krajích zorného pole a s defekty, jejichž hranice není tolik zřetelná na vstupních obrazech. Nutno zmínit, že zákazník má zájem o kompletní řešení scanneru i s detekčním softwarem a vývoj tohoto zařízení bude pokračovat i po závěru této diplomové práce.
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Robot s autonomním audio-vizuálním řízením / Robot with autonomous audio-video controlDvořáček, Štěpán January 2019 (has links)
This thesis describes the design and realization of a mobile robot with autonomous audio-visual control. This robot is able of movement based on sensors consisting of camera and microphone. The mechanical part consists of components made with 3D print technology and omnidirectional Mecanum wheels. Software utilizes OpenCV library for image processing and computes MFCC a DTW for voice command detection.
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Určení parametrů pohybu ze snímků kamery / Determination of Motion Parameters in Machine VisionDušek, Stanislav January 2009 (has links)
This thesis describe about determination of camera motion parameters in plane. At first there are introduce the basics of motion tracking, is focused to find out displacement between two input images. Below is describe the algorithm GoodFeatruresToTrack, which find out the most significant point in a first image. The point is search out the good point, which will be easy to track in next image, reduce the data volume and prepare the input information (array of significant point) for the algorithm Lucas-Kanade optical flow. In second part is deal with processing and utilization estimations optical flow. There is median filtration, below is describe computation of homogenous transformation, which describe all affine transformation in affine space. As the result are coordinates, which describe the shift between the two input images as X-axis and Y-axis value. The project used the library Open Computer Vision.
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Využití termovizní kamery pro měření teploty elektrických strojů / Utilization of infrared camera for temperature measurement of electrical machinesLíbal, Jan January 2009 (has links)
The master‘s thesis deals with utilization of infrared camera for temperature measurement of electrical machines. The first part describes non-contact temperature measuring, the second part describes principle of sensors that evaluate quantity of incident infrared radiation. In the next part there is termovision camera SAT-HY 6800 presented and the instructional manual for SAT Report computer programme created. This computer programme is used for analyzing of termovision pictures from the SAT-HY 6800 termovison camera. The chapter 7 describes temperature measuring of one-phase asynchronous motor type J22TO484. The chapter 8 describes temperature measuring of semiconductor components of EC motor G6 series. Both of these motors are produced by ATAS elektromotory Náchod a.s. The last part of the thesis describes creation of animation of one-phase asynchronous motor type J22TO455. The animation was created in 3ds Max computer programme.
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Analýza fotovoltaických článků pomocí fotoluminiscence / Analyse of photovoltaic solar cells by the photoluminescence methodBaura, Tomáš January 2012 (has links)
This thesis deals with the analysis of solar cells by photoluminescence method. Photoluminescence method is based on the excitation of luminescence radiation of the solar cell material by an external excitation light source. This method can detect various types of defects in the material solar cells. The main objective is the design and realization of a measuring system defects of solar cells, which is based on this method. For excitation of luminescence is used LED array. For the detection of luminescence is used CCD camera with IR optical filter. To filter out the excitation light radiation is used disc screen and optical interrupter. The parameters and options of this measuring system are verified and characterized by test measuring for example the achievable rotation speed of screen and response of optical interrupter. At the end is tested detection of luminescence radiation of solar cells in the measuring system. The measured images are compared with the method of electroluminescence.
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