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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Meteorologiska mätningar med drönare / Meteorological measurements with drones

Greenland, Christopher January 2019 (has links)
Studien handlade om att belysa hur UAV:s kan komma till nytta i meteorologisk forskning och att ta reda på hur bra drönare är på att mäta meteorologiska storheter. Drönare, som också kallas UAV:s (Unmanned Aerial Vehicle) är mindre obemmanade luftfartyg som kan flyga autonomt eller fjärrstyras. Idag används drönare alltmer i meteorologi vilket beror mycket på den tekniska utvecklingen. Exempel på meteorologiska applikationer är mätning av vindhastighet och koncentrationen av koldioxid i luften som kan användas för att studera de lägsta atmosfäriska skikten. Storheter som mättes i detta projekt var vindhastighet, vindriktning, temperatur och relativ fuktighet på olika höjder. Mätningarna gjordes två gånger i en mätstation i Marsta, som ligger utanför Uppsala. Efteråt jämfördes datan från drönaren med data från en instrumenterad mast vid väderstationen. Resultaten visade att drönarens vindprofiler stämde ganska väl överens med mastens vindprofiler och den logaritmiska vindlagen. Under den första fältmätningen uppskattade drönaren att vindhastigheten var 8.13 ± 1.33 m/s vid hovring på tio meters höjd medan masten angav 8.41 ± 0.958 m/s. Drönarens mätvärden för vindriktningen var ibland bra och ibland mindre bra. Mätvärdena för temperaturen och den relativa fuktigheten avvek med upp mot 1 ◦C respektive 10 procentenheter. / The aim of this report was to study how UAV:s can be applied in meteorological research and find out how good drones are at measuring meteorological parameters. A drone, also known as an UAV (Unmanned Aerial Vehicle) is a smaller unmanned aircraft that can fly autonomously or under remote control. Today, drones are used more frequently in meteorology, mostly due to the recent technological development. Examples of meteorological applications include measurements of wind speed and the amount of carbon dioxide in the air which can be used to analyze the lower parts of the atmosphere. In this project, the wind speed and its direction, the temperature and the relative humidity were measured at different heights. The measurements took place twice in Marsta which is a field station outside Uppsala. Then, the data from the drone was compared to the data from a weather tower at the instrumented station. The results showed that the drone’s wind profiles were relatively similar to the profiles according to the tower and the logarithmic wind profiles. For instance, during the first flight the drone estimated the wind speed to be 8.13 ± 1.33 m/s while hovering ten metres above the ground. The tower measured 8.41 ± 0.958 m/s at the same height. The drone’s estimations of the wind direction were sometimes accurate and sometimes not accurate. The temperature and relative humidity however was different by 1 ◦C and ten percentage units respectively.
212

Armed Drones: An Age Old Problem Exacerbated by New Technology

Frazier, Grant H 01 January 2016 (has links)
The purpose of this thesis is to examine the history behind and the use of militarized drones in modern day conflicts, and to conclude whether the use of these machines, with special attention to the United States, is legal, ethical, and morally defensible. In achieving the aforementioned goals, shortcomings of current policy surrounding drone warfare will be highlighted, acting as the catalyst for a proposal for changes to be made to better suit legal, ethical, and moral considerations. The proposal of a policy to help us work with armed drones is due to the fact that this thesis acknowledges that armed drones, like guns, nuclear weapons, or any type of military technology, is here to stay and that once we acknowledge that fact, the most important step is to make sure we have the right tools to judge the conduct of conflict carried out using armed drones or other weapons that raise similar issues and questions.
213

Autonomous Systems in Society and War : Philosophical Inquiries

Johansson, Linda January 2013 (has links)
The overall aim of this thesis is to look at some philosophical issues surrounding autonomous systems in society and war. These issues can be divided into three main categories. The first, discussed in papers I and II, concerns ethical issues surrounding the use of autonomous systems – where the focus in this thesis is on military robots. The second issue, discussed in paper III, concerns how to make sure that advanced robots behave ethically adequate. The third issue, discussed in papers IV and V, has to do with agency and responsibility. Another issue, somewhat aside from the philosophical, has to do with coping with future technologies, and developing methods for dealing with potentially disruptive technologies. This is discussed in papers VI and VII. Paper I systemizes some ethical issues surrounding the use of UAVs in war, with the laws of war as a backdrop. It is suggested that the laws of war are too wide and might be interpreted differently depending on which normative moral theory is used. Paper II is about future, more advanced autonomous robots, and whether the use of such robots can undermine the justification for killing in war. The suggestion is that this justification is substantially undermined if robots are used to replace humans to a high extent. Papers I and II both suggest revisions or additions to the laws or war. Paper III provides a discussion on one normative moral theory – ethics of care – connected to care robots. The aim is twofold: first, to provide a plausible and ethically relevant interpretation of the key term care in ethics of care, and second, to discuss whether ethics of care may be a suitable theory to implement in care robots. Paper IV discusses robots connected to agency and responsibility, with a focus on consciousness. The paper has a functionalistic approach, and it is suggested that robots should be considered agents if they can behave as if they are, in a moral Turing test. Paper V is also about robots and agency, but with a focus on free will. The main question is whether robots can have free will in the same sense as we consider humans to have free will when holding them responsible for their actions in a court of law. It is argued that autonomy with respect to norms is crucial for the agency of robots. Paper VI investigates the assessment of socially disruptive technological change. The coevolution of society and potentially disruptive technolgies makes decision-guidance on such technologies difficult. Four basic principles are proposed for such decision guidance, involving interdisciplinary and participatory elements. Paper VII applies the results from paper VI – and a workshop – to autonomous systems, a potentially disruptive technology. A method for dealing with potentially disruptive technolgies is developed in the paper. / <p>QC 20130911</p>
214

Navigation d'un avion miniature de surveillance aérienne en présence de vent / Small lightweight aircraft navigation in the presence of wind

Brezoescu, Cornel-Alexandru 28 October 2013 (has links)
Ce travail de thèse porte sur le comportement en vol de drones légers à voilure fixe en présence de vent. Ces dispositifs aériens offrent une transition en douceur de la théorie à la pratique dans le domaine de la commande autonome. En outre, ils fournissent une solution appropriée dans des environnements inaccessibles ou dangereux pour les êtres humains. Cependant, ne pas avoir un pilote humain à bord implique que les UAV reposent sur l'automatisation pour naviguer ou pour éviter les obstacles. De plus, leur vitesse de fonctionnement relativement faible les rend particulièrement affectés par le vent. Motivé par ces considérations, les objectifs de ce travail de recherche visent des résultats théoriques et expérimentaux dans le domaine de la conception de contrôleurs de vol pour les petits drones à voilure fixe de configuration classique permettant le vol stable dans les conditions de vent. Pour atteindre ces objectifs, plusieurs domaines de recherche sont abordés dans cette thèse comme il suit.Tout d'abord, une étude approfondie sur l'aspect aérodynamique de l'avion est menée afin d'obtenir le modèle mathématique du véhicule en présence de vent. En outre, des modèles qui reproduisent le comportement essentiel du système dans un contexte simplifié sont analysés. Par conséquent, des modèles non linéaires de complexité réduite, qui sont plus simples à analyser et simuler et plus adaptés à la conception de stratégies de contrôle, sont présentés. Deuxièmement, le problème à résoudre est formulé comme un problème de suivi de trajectoire dans lequel le dispositif de commande de vol doit être en mesure de diriger le véhicule le long d'un chemin. Des stratégies de navigation sont élaborées dans le but d'éliminer la déviation de l'avion par rapport à la trajectoire de référence. Le vent est considéré d'abord mesurable par une station au sol et, ensuite, estimé en utilisant une navigation adaptative basée sur la théorie de Lyapunov. La performance de l'algorithme d'estimation est améliorée en utilisant la stratégie de commande basée sur la méthode des fonctions de réglage. Le troisième axe de recherche est la conception et la mise en œuvre d'un dispositif expérimental qui se compose d'une station au sol utilisée pour la visualisation et la commande à distance du drone et d'un pilote automatique embarqué contenant la plate-forme de vol munie d'avionique appropriée. / This research work addresses the flight behavior of lightweight fixed-wing UAVs in windy conditions. Such aerial devices offer a smooth transition of autonomous flight control design from theory to practice in addition to providing a proper solution in environments inaccessible or dangerous to human beings. However, not having a human pilot onboard implies that UAVs rely on automation to navigate or to avoidobstacles. In addition, their relatively low operating speed makes them particularly affected by the wind field.Motivated by theses considerations, the objectives of the current research aim theoretical and experimental results in designing flight controllers for small fixed-wing UAVs of conventional configuration allowing for stable flight in windy conditions. In order to achieve these objectives, several research areas are being addresses in this thesis as it follows. First, a comprehensive study on the aerodynamic aspect of the aiplane in conducted in order to obtain the mathematical model of the aircraft in presence of wind. Further, models thet reproduce the essential behavior of the system in a simplified context are analyzed. consequently, nonlinear models of reduced complexity, that are easier to analyze and simulate and more adapted to the design of control strategies, are presented. Secondly, the problem to be solved is formulated as a trajectory following problem in which the flight controller must be able to steer the vehicle along a path. Navigation strategies are developed in order to minimize the airplane deviation relative to the reference trajectory. the wind is considered initially measurable by a ground station and, then, estimated using adaptative navigation based on the theory of Lyapunov. The performance of the estimation algorithm is improved using control design based on thr tuning functions method. The third axis of research is the design and the implementation of an experimental setup which consists of a ground station used for visualization and control purposes and an embedded autopilot architecture containing the airframe platform equipped with appropriate avionics.
215

Robotic hummingbird: design of a control mechanism for a hovering flapping wing micro air vehicle

Karasek, Matej 21 November 2014 (has links)
<p>The use of drones, also called unmanned aerial vehicles (UAVs), is increasing every day. These aircraft are piloted either remotely by a human pilot or completely autonomously by an on-board computer. UAVs are typically equipped with a video camera providing a live video feed to the operator. While they were originally developed mainly for military purposes, many civil applications start to emerge as they become more affordable.<p><p><p>Micro air vehicles are a subgroup of UAVs with a size and weight limitation; many are designed also for indoor use. Designs with rotary wings are generally preferred over fixed wings as they can take off vertically and operate at low speeds or even hover. At small scales, designs with flapping wings are being explored to try to mimic the exceptional flight capabilities of birds and insects. <p><p><p>The objective of this thesis is to develop a control mechanism for a robotic hummingbird, a bio-inspired tail-less hovering flapping wing MAV. The mechanism should generate moments necessary for flight stabilization and steering by an independent control of flapping motion of each wing.<p><p><p>The theoretical part of this work uses a quasi-steady modelling approach to approximate the flapping wing aerodynamics. The model is linearised and further reduced to study the flight stability near hovering, identify the wing motion parameters suitable for control and finally design a flight controller. Validity of this approach is demonstrated by simulations with the original, non-linear mathematical model.<p><p><p>A robotic hummingbird prototype is developed in the second, practical part. Details are given on the flapping linkage mechanism and wing design, together with tests performed on a custom built force balance and with a high speed camera. Finally, two possible control mechanisms are proposed: the first one is based on wing twist modulation via wing root bars flexing; the second modulates the flapping amplitude and offset via flapping mechanism joint displacements. The performance of the control mechanism prototypes is demonstrated experimentally. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
216

Concevoir l'interaction avec des systèmes de drones militaires : une approche incarnée et située. / Designing interaction with military UAV systems : an embodied and situated approach

Large, Anne-Claire 14 December 2015 (has links)
Cette thèse s’inscrit dans une approche incarnée et située de la cognition humaine et de l’ergonomie des interfaces Homme-Machine (IHM). En rupture avec les théories computo-symboliques, cette approche considère que la cognition a pour seule vocation l’action dans le but de s’adapter au monde. Appliquée à l’ergonomie des IHM, elle met l’accent sur la perception, l’action et le contexte comme éléments clés de l’interaction Homme-Machine. Cette vision de l’ergonomie est ici mise au service de la conception de stations sol de drones militaires, sur lesquelles le manque de sollicitations perceptivo-motrices et le caractère isolé des opérateurs contribuent à une accidentologie symptomatique. L’objet de cette thèse est donc de montrer en quoi l’approche incarnée et située permet de guider une démarche ergonomique et, en particulier, la conception de deux stations sol de drones militaires développés par Airbus Defence and Space. Dans un premier temps, une analyse centrée sur les aspects moteurs, perceptifs et contextuels de l’activité des opérateurs de drones est réalisée. La seconde étape est dédiée à la définition d’une organisation matériel-logiciel standardisée pour tous types de drones. Cette organisation repose sur l’exploitation de processus perceptivo-moteurs, notamment au moyen du paradigme Stimulus-Response Compatibility (SRC). En troisième lieu, est présentée la conception matérielle et logicielle de deux stations sol de drones adaptées à leurs contextes respectifs d’utilisation. Des moyens de vérification (e.g. tests utilisateurs) sont mis en œuvre pour valider les solutions proposées. Les résultats obtenus montrent que la démarche adoptée permet d’améliorer significativement certains aspects de l’activité des opérateurs de drones, en particulier en termes de performances et de charge mentale. D’autre part, ces travaux soulignent l’intérêt de l’approche incarnée et située, et sa forte valeur applicative tant au sein de la démarche ergonomique que dans un cycle de conception industrielle. / Cette thèse s’inscrit dans une approche incarnée et située de la cognition humaine et de l’ergonomie des interfaces Homme-Machine (IHM). En rupture avec les théories computo-symboliques, cette approche considère que la cognition a pour seule vocation l’action dans le but de s’adapter au monde. Appliquée à l’ergonomie des IHM, elle met l’accent sur la perception, l’action et le contexte comme éléments clés de l’interaction Homme-Machine. Cette vision de l’ergonomie est ici mise au service de la conception de stations sol de drones militaires, sur lesquelles le manque de sollicitations perceptivo-motrices et le caractère isolé des opérateurs contribuent à une accidentologie symptomatique. L’objet de cette thèse est donc de montrer en quoi l’approche incarnée et située permet de guider une démarche ergonomique et, en particulier, la conception de deux stations sol de drones militaires développés par Airbus Defence and Space. Dans un premier temps, une analyse centrée sur les aspects moteurs, perceptifs et contextuels de l’activité des opérateurs de drones est réalisée. La seconde étape est dédiée à la définition d’une organisation matériel-logiciel standardisée pour tous types de drones. Cette organisation repose sur l’exploitation de processus perceptivo-moteurs, notamment au moyen du paradigme Stimulus-Response Compatibility (SRC). En troisième lieu, est présentée la conception matérielle et logicielle de deux stations sol de drones adaptées à leurs contextes respectifs d’utilisation. Des moyens de vérification (e.g. tests utilisateurs) sont mis en œuvre pour valider les solutions proposées. Les résultats obtenus montrent que la démarche adoptée permet d’améliorer significativement certains aspects de l’activité des opérateurs de drones, en particulier en termes de performances et de charge mentale. D’autre part, ces travaux soulignent l’intérêt de l’approche incarnée et située, et sa forte valeur applicative tant au sein de la démarche ergonomique que dans un cycle de conception industrielle.
217

Viltinventering med hjälp av drönare utrustad med termisk- och RGB kamera. : Identifiering och artbestämning av älg och annat klövvilt / Wildlife inventory with drone equipped with RGB and thermal camera : Identification and species determination of moose and other cloven-hoofed animals

Eilert, Annette, Magnusson, Katrin January 2020 (has links)
Betesskador på skog kostar både skogsägare och industri stora summor pengar. Ett sätt att minska betesskador kan vara bättre kontroll över populationsstorleken av klövvilt. I Sverige används flera olika etablerade viltinventeringsmetoder. Svagheten är att de baseras på trender, index och avskjutningar mer än att få fram en siffra på antalet djur. En tillförlitlig inventeringsmetod är av stor vikt som beslutsunderlag till förvaltningsplaner. Drönare är ett obemannat luftfartyg som kan utrustas med olika kameror och sensorer. Tidigare fältstudier har visat att värme från vilt kan plockas upp av en drönare utrustad med termisk kamera. Svårigheten har varit att få tillförlitlighet vid artbestämning av vilt med enbart termiska kamera. I denna studie utfördes en viltinventering av ett 506 ha stort område norr om Ljungby i Kronobergs län under januari 2020. Med hjälp av en drönare utrustad med både termisk och RGB kamera utfördes en totalinventering av området. Resultatet visar att kombinationen av både termisk och RGB kamera ökar tillförlitligheten vid artbestämning av vilt. Metodens svagheter är täta krontak av gran, gällande regelverk från transportstyrelsen samt drönarens begränsande batterikapacitet. Slutsatsen är att vilt säkrare kan identifieras och artbestämmas med kombinationen av termisk- och RGB kamera jämfört med enbart termisk kamera men att metoden behöver vidareutvecklas.
218

UAV DETECTION AND LOCALIZATION SYSTEM USING AN INTERCONNECTED ARRAY OF ACOUSTIC SENSORS AND MACHINE LEARNING ALGORITHMS

Facundo Ramiro Esquivel Fagiani (10716747) 06 May 2021 (has links)
<div> The Unmanned Aerial Vehicles (UAV) technology has evolved exponentially in recent years. Smaller and less expensive devices allow a world of new applications in different areas, but as this progress can be beneficial, the use of UAVs with malicious intentions also poses a threat. UAVs can carry weapons or explosives and access restricted zones passing undetected, representing a real threat for civilians and institutions. Acoustic detection in combination with machine learning models emerges as a viable solution since, despite its limitations related with environmental noise, it has provided promising results on classifying UAV sounds, it is adaptable to multiple environments, and especially, it can be a cost-effective solution, something much needed in the counter UAV market with high projections for the coming years. The problem addressed by this project is the need for a real-world adaptable solution which can show that an array of acoustic sensors can be implemented for the detection and localization of UAVs with minimal cost and competitive performance.<br><br></div><div> In this research, a low-cost acoustic detection system that can detect, in real time, about the presence and direction of arrival of a UAV approaching a target was engineered and validated. The model developed includes an array of acoustic sensors remotely connected to a central server, which uses the sound signals to estimate the direction of arrival of the UAV. This model works with a single microphone per node which calculates the position based on the acoustic intensity change produced by the UAV, reducing the implementation costs and being able to work asynchronously. The development of the project included collecting data from UAVs flying both indoors and outdoors, and a performance analysis under realistic conditions. <br><br></div><div> The results demonstrated that the solution provides real time UAV detection and localization information to protect a target from an attacking UAV, and that it can be applied in real world scenarios. </div><div><br></div>
219

Модел оптимизације доставе пошиљака у системима са хетерогеним доставним возилима / Model optimizacije dostave pošiljaka u sistemima sa heterogenim dostavnim vozilima / The optimisation model for parcele delivery in systems with heterogeneous vehicles

Dumnić Slaviša 30 September 2019 (has links)
<p>Машинско учење и неуронске мреже су алати који налазе све већу<br />примену у решавању практичних проблема. За креирање неуронске<br />мреже потребан је скуп података, који може бити прикупљен на<br />различите начине. У овој тези је показано да се подаци за тренинг<br />неуронске мреже могу успешно прикупити креирањем веб игре.<br />Сакупљени скуп података садржи стратегије решавања проблема<br />трговачког путника и проблема рутирања возила.</p> / <p>Mašinsko učenje i neuronske mreže su alati koji nalaze sve veću<br />primenu u rešavanju praktičnih problema. Za kreiranje neuronske<br />mreže potreban je skup podataka, koji može biti prikupljen na<br />različite načine. U ovoj tezi je pokazano da se podaci za trening<br />neuronske mreže mogu uspešno prikupiti kreiranjem veb igre.<br />Sakupljeni skup podataka sadrži strategije rešavanja problema<br />trgovačkog putnika i problema rutiranja vozila.</p> / <p>Machine learning and neural networks are the tools that are finding more and<br />more fields of application in solving practical problems. For the creation of<br />the neural networks, data can be successfully collected by creating a web<br />game. The data collected in this manner has strategic solutions for the<br />problems of Travel salesperson problem and vehicle routing problem.</p>
220

Redefining Horizons: A Study on Business Model Innovation for the Commercialization of Services within Urban Air Mobility / Nya Horisonter: Affärsmodellssinnovation för Kommersialiseringen av Tjänster inom Uraban Air Mobility

Landberg, Otto, Blomgren, Jacob January 2023 (has links)
Urban air mobility has gained increased attention in recent years due to the emergence of novel technologies. Several use cases within different industries exist. These services can substitute existing services as well as offering entirely new ones. Previous research has focused on novel technologies and changes needed to be made in order for the technology to be established in the market. However, non-technological aspects are lacking, specifically concerning suitable business models. Thus, the role of business models, and changes related to these, required for a commercialization of urban air mobility services constitutes a research gap and are of interest for further exploration. To understand how actors are changing their business models to commercialize urban air mobility three different case studies were conducted on three projects focusing on use cases connected to urban air mobility. Interviews were used as the primary data gathering method, and in total 13 were conducted. The theoretical STOF framework, which delimits the business model into four domains, was used to identify potential changes. The main results indicate important future actors in a commercialization, the degree of change of these actors and potential challenges for them. Due to the uncertainty of the role business models play in a commercialization of urban air mobility services, this thesis will contribute to bridging this research gap. Concrete changes are identified, as well as specific business model areas in need of more attention. Furthermore, the thesis contributes to the literature concerning challenges related to urban air mobility services, as well as suggesting how they can be handled. Finally, the thesis evaluates and explains how the STOF framework can be extended to new industries. / Urban air mobility har fått ökad uppmärksamhet de senaste åren på grund av uppkomsten av nya teknologier. Flera användningsområden inom olika branscher existerar. Dessa tjänster kan ersätta befintliga tjänster samt erbjuda helt nya. Tidigare forskning har främst fokuserat på nya teknologier och förändringar som behöver göras för att tekniken ska etableras på marknaden. Emellertid saknas aspekter som inte är teknologiska, särskilt lämpliga affärsmodeller. Därmed är inte affärsmodellens roll samt nödvändiga förändringar relaterade till den för en kommersialisering av urban air mobility tillräckligt belysta och är därför intressant för vidare forskning. För att förstå hur aktörer ändrar sina affärsmodeller för att kommersialisera urban air mobility genomfördes tre olika fallstudier på tre projekt som fokuserar på användningsområden kopplade till urban air mobility. Den teoretiska STOF modellen, som avgränsar affärsmodellen i fyra områden, användes för att identifiera potentiella förändringar för de olika projektaktörernas affärsmodeller. De främsta resultaten indikerar vilka de viktiga framtida aktörerna i en kommersialisering är, graden av affärsmodellsförändring för dem, samt potentiella utmaningar. På grund av osäkerheten kring vilken roll affärsmodeller har vid kommersialisering av tjänster relaterade till urban air mobility bidrar denna avhandling till att ytterligare belysa detta forskningsområde. Konkret identifierar avhandlingen nödvändiga affärsmodellsförändringar för de olika aktörerna, samt specifika områden inom affärsmodellen som behöver mer uppmärksamhet. Dessutom bidrar avhandlingen till forskningslitteraturen om utmaningar relaterade till urban air mobility tjänster, samt föreslår hur de kan hanteras. Slutligen utvärderar och förklarar avhandlingen hur STOF modellen kan utökas till fler branscher än internetbaserade tjänster.

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