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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.
171

ESTIMATIVA DO ÍNDICE DE SEVERIDADE DE FERRUGEM ASIÁTICA NA CULTURA DA SOJA POR MEIO DE IMAGENS OBTIDAS COM AERONAVE REMOTAMENTE PILOTADA

Lacerda, Victor Schnepper 02 February 2017 (has links)
Made available in DSpace on 2017-07-21T14:19:30Z (GMT). No. of bitstreams: 1 Victor Schnepper Lacerda.pdf: 2047594 bytes, checksum: f0234089904caa6e03e22d3efba8394c (MD5) Previous issue date: 2017-02-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Soybean cultivation is of great importance to the Brazilian economy, and one of the major obstacles to its high productivity is the Asian soybean rust, a disease caused by the fungus Phakopsora pachyrhizi. The main measure to control the damage caused by this disease is the application of fungicides at the appropriate time, but the biggest obstacle to its implementation is the difficult detection of Asian rust in its early stages. In this sense, remote sensing combined with the use of unmanned aerial vehicles (UAVs) has potential for disease detection, especially for providing information that is hard to assess by traditional means, and for the advantages of quality and cost of this technology. The present work explores the use of unmanned aerial vehicles to detect and predict the severity of Asian soybean rust by use of digital image processing and data mining techniques for retrieval of predictive models of severity in different development stages. The models obtained showed satisfactory potential for Asian rust detection, and a high correlation between disease severity and the visible spectrum (RGB camera), as it was possible to obtain correlation coefficients greater than 93% after the R5 development stage of the soybean crop. / O cultivo da soja (Glycine max) é importante para a economia brasileira, sendo que um dos principais obstáculos à alta produtividade na lavoura é a ferrugem asiática, causada pelo fungo Phakopsora pachyrhizi. O principal fator para o controle de danos causados por essa doença é a aplicação de fungicidas em momento apropriado, porém o maior obstáculo para uso dessa medida é a difícil detecção da ferrugem asiática em estágios iniciais. Nesse sentido, o sensoriamento remoto aliado ao uso de veículos aéreos remotamente pilotados apresenta potencial para detecção da doença, principalmente por fornecer informação de difícil acesso aos meios tradicionais e pelas vantagens de qualidade e custo dessa tecnologia. O presente trabalho explora o uso de veículos aéreos remotamente pilotados para detecção e predição de severidade da ferrugem asiática da soja, associados a técnicas de processamento digital de imagens e de mineração de dados, visando a obtenção de modelos preditivos de severidade nos diferentes estágios de desenvolvimento da soja. Os modelos obtidos demonstraram potencial para a detecção da ferrugem asiática, e uma boa correlação da severidade da doença com o espectro visível (câmera RGB), ao passo que foi possível obter coeficientes de correlação maiores que 93% utilizando o algoritmo SMOREG após o estádio R5 de desenvolvimento da cultura da soja.
172

Adaptive Estimation and Control with Application to Vision-based Autonomous Formation Flight

Sattigeri, Ramachandra Jayant 17 May 2007 (has links)
The role of vision as an additional sensing mechanism has received a lot of attention in recent years in the context of autonomous flight applications. Modern Unmanned Aerial Vehicles (UAVs) are equipped with vision sensors because of their light-weight, low-cost characteristics and also their ability to provide a rich variety of information of the environment in which the UAVs are navigating in. The problem of vision based autonomous flight is very difficult and challenging since it requires bringing together concepts from image processing and computer vision, target tracking and state estimation, and flight guidance and control. This thesis focuses on the adaptive state estimation, guidance and control problems involved in vision-based formation flight. Specifically, the thesis presents a composite adaptation approach to the partial state estimation of a class of nonlinear systems with unmodeled dynamics. In this approach, a linear time-varying Kalman filter is the nominal state estimator which is augmented by the output of an adaptive neural network (NN) that is trained with two error signals. The benefit of the proposed approach is in its faster and more accurate adaptation to the modeling errors over a conventional approach. The thesis also presents two approaches to the design of adaptive guidance and control (G&C) laws for line-of-sight formation flight. In the first approach, the guidance and autopilot systems are designed separately and then combined together by assuming time-scale separation. The second approach is based on integrating the guidance and autopilot design process. The developed G&C laws using both approaches are adaptive to unmodeled leader aircraft acceleration and to own aircraft aerodynamic uncertainties. The thesis also presents theoretical justification based on Lyapunov-like stability analysis for integrating the adaptive state estimation and adaptive G&C designs. All the developed designs are validated in nonlinear, 6DOF fixed-wing aircraft simulations. Finally, the thesis presents a decentralized coordination strategy for vision-based multiple-aircraft formation control. In this approach, each aircraft in formation regulates range from up to two nearest neighboring aircraft while simultaneously tracking nominal desired trajectories common to all aircraft and avoiding static obstacles.
173

Autonomous Landing Of Unmanned Aerial Vehicles

Singh, Shashiprakash 02 1900 (has links)
In this thesis the problem of autonomous landing of an unmanned aerial vehicle named AE-2 is addressed. The guidance and control technique is developed and demonstrated through numerical simulation results. The complete work includes Mathematical modeling, Control design, Guidance and State estimation for AE-2, which is a fixed wing vehicle with 2m wing span and 6kg weight. The aerodynamic data for AE-2 is available from static wind tunnel tests. Functional fit is done on the wind tunnel data with least squares method to find static aerodynamic coefficients. The aerodynamic forces and moment coefficients are highly nonlinear some of them are partitioned in two zones based on the angle of attack. The dynamic derivatives are found with Athena Vortex Lattice software. For the validation of vortex lattice method the static derivatives obtained by the wind tunnel tests and vortex lattice method, are compared before finding dynamic derivatives. The dynamics of the servo actuators for the aerodynamic control surfaces is incorporated in the simulation. The nonlinear dynamic inversion technique has been used for the guidance and control design. The control is structured in two loops, outer and inner loop. The goal of outer loop is to track the guidance commands of altitude, roll angle and yaw angle by converting them into body rate commands through dynamic inversion. The inner loop than tracks these commanded roll rate, pitch rate and yaw rate by finding the required deflection of control surfaces. The forward velocity of the vehicle is controlled by varying the throttle. A controller for actuator is also designed to reduce the lag. The guidance for landing consists of three phases approach, glideslope and flare. During approach the vehicle is aligned with the runway and guided to a specified height from where the glideslope can begin. The glideslope is straight line path specified by a flight path angle which is restricted between 3 to 4 degree. At the end of glideslope which is marked by flare altitude the flare maneuver begins which is an exponential curve. The problem of transition between the glideslope and flare has addressed by ensuring continuity and smoothness at transition. The exponential curve of flare is designed to end below the ground so that it intersects the ground at a prespecified point. The sink rate at touchdown is also controlled along with the location of touchdown point. The state estimation has been done with Extended Kalman Filter in continuous discrete formulation. The external disturbances like wind shear and wind gust are accounted by appending them in state variables. Further the control design with guidance is tested from various initial conditions, in presence of wind disturbances. The designed filter has also been tested for parameter uncertainty.
174

Reactive navigation of a fleet of drones in interaction / Navigation réactive de drones en interaction dans une flottille

Saif, Osamah 23 March 2016 (has links)
De nos jours, les applications utilisant des quadrirotors autonomes sont en plein essor. La surveillance et la sécurité de sites industriels ou sensibles, de zones géographiques pour l’agriculture par exemple sont quelques-unes des applications les plus célèbres des véhicules aériens sans pilote (UAV). Actuellement, certains chercheurs et scientifiques se concentrent sur le déploiement multi-drones pour l’inspection et la surveillance de vastes zones. L’objectif de cette thèse est de concevoir des algorithmes afin de réaliser une commande de vol en formation distribuée/décentralisée de multi-UAVs en temps réel dans une perspective de systèmes de systèmes. Tout d’abord, nous avons passé en revue certains travaux récents de la littérature sur la commande de vol en formation et la commande de quadrirotors. Nous avons présenté une brève introduction sur les systèmes de systèmes, leur définition et leurs caractéristiques. Ensuite, nous avons introduit la commande de vol en formation avec ses structures les plus utilisées dans la littérature. Nous avons alors présenté quelques travaux existants traitant du flocking (comportement de regroupement en flotte), les méthodes de modélisation les plus utilisés pour les quadrirotors et quelques approches de commande les plus utilisées pour stabiliser des quadrirotors. Deuxièmement, nous avons utilisé la structure de la commande comportementale pour réaliser un vol en formation de plusieurs UAVs. Nous avons conçu un comportement pour réaliser le vol en formation de multi-UAVs sans fragmentation. Le comportement proposé traite le problème flocking dans une perspective globale, c’est-à-dire, nous avons inclus une tendance dans chaque drone pour former une formation. Les défis des Systèmes de systèmes nous a motivés à chercher des algorithmes de flocking et de consensus introduits dans la littérature qui peuvent être utiles pour répondre à ces défis. Cela nous a amenés à proposer quatre lois de commande en visant à être compatibles avec le modèle non linéaire des quadrirotors et pouvant être expérimentés sur des plates-formes réelles. Les lois de commande ont été exécutées à bord de chaque quadrirotor dans la formation et chaque quadrirotor interagit avec ses voisins pour assurer un vol en formation sans collision. Enfin, nous avons validé nos lois de commande par des simulations et des expériences en temps réel. Pour la simulation, nous avons utilisé un simulateur de multi quadrirotors développé au laboratoire Heudiasyc. Pour les expériences, nous avons mis en œuvre nos lois de contrôle sur des quadrirotors ArDrone2 évolués dans un environnement intérieur équipé d’un système de capture de mouvement (Optitrack). / Nowadays, applications of autonomous quadrotors are increasing rapidly. Surveillance and security of industrial sites, geographical zones for agriculture for example are some popular applications of Unmanned Aerial Vehicles (UAVs). Nowadays, researchers and scientists focus on the deployment of multi-UAVs for the inspection and the surveillance of large areas. The objective of this thesis is to design algorithms and techniques to perform a real-time distributed/decentralized multi-UAVs flight formation control, from a system of systems perspective. Firstly, we reviewed recent works of the literature about flight formation control and the control of quadrotors. We presented a brief introduction about systems of systems, their definition and characteristics. Then, we introduced the flight formation control with its most used structures in the literature, some existing works dealing with flocking. Finally, we presented the most used modeling methodologies for quadrotors and some control approaches that are used to stabilize quadrotors. Secondly, we used the behavioral-based control structure to achieve a multiple UAV flocking. We conceived a behavior intending to address the control design towards a successful achievement of the flocking task without fragmentation. The proposed behavior treats the flocking problem from a global perspective, that is, we included a tendency of separated UAVs to form a flock.System of systems challenges motivated us to look for flocking and consensus algorithms introduced in the literature that could be helpful to answer to these challenges. This led us to propose four flocking control laws aiming at being compatible with the nonlinear model of quadrotors and at being implemented on experimental platforms. The control laws were run aboard each quadrotor in the flock. By running the control law, each quadrotor interacts with its neighbors to ensure a collision-free flocking. Finally, we validated our proposed control laws by simulations and real-time experiments. For the simulation, we used a PC-based simulator of flock of multiple quadrotors which was developed at Heudiasyc laboratory. For experiments, we implemented our control laws on ArDrone2 quadrotors evolved in an indoor environment equipped with an Optitrack motion capture system.
175

Développement d’un estimateur d’état non linéaire embarqué pour le pilotage-guidage robuste d’un micro-drone en milieu complexe / Nonlinear state estimation for guidance and navigation of unmanned aerial vehicles flying in a complex environnement

Condomines, Jean-Philippe 05 February 2015 (has links)
Le travail effectué au cours de cette thèse tente d’apporter une solution algorithmique à la problématique de l’estimation de l’état d’un mini-drone en vol qui soit compatible avec les exigences d’embarquabilité inhérentes au système. Il a été orienté vers les méthodes d’estimation non linéaire à base de modèles. Les algorithmes d’estimation, d’état ou de paramètres, et de contrôle apparaissent primordiaux, lorsque la technologie des capteurs et des actionneurs, pour des raisons de coût et d’encombrement essentiellement, ne permet pas de disposer de capacités illimitées. Ceci est particulièrement vrai dans le cas des micro- et des mini-drones. L’estimation permet de fusionner en temps réel les informations imparfaites provenant des différents capteurs et de fournir une estimation, par exemple de l’état du drone (orientation, vitesse, position) au calculateur embarqué où sont implémentés les algorithmes de commande de l’engin. Ce contrôle de l’appareil doit garantir sa stabilité en boucle fermée quelque soit l’ordre de consigne fourni directement par l’opérateur ou par tout système automatique de gestion du vol et assurer que celle-ci soit correctement recopiée. Estimation et commande participent donc grandement au succès de toute mission. Une dimension extrêmement importante qui a conditionné les travaux entrepris tout au long de cette thèse concerne la capacité d’emport des mini-drones que nous considérons. En effet, celle-ci, relativement limitée, et couplée à la volonté de ne pas grever les budgets de développement de tout mini-drone, autorise uniquement l’intégration de matériels dits bas-coûts. Malgré les progrès significatifs de la miniaturisation et l’augmentation continuelle des capacités de calcul embarqué (loi de Moore), les mini-drones d’intérêt considérés ici n’embarquent donc que des capteurs aux performances limitées dans un contexte où cette catégorie d’engins autonomes est amenée à être de plus en plus fréquemment exploitée pour remplir des missions elles-mêmes toujours plus nombreuses. Celles-ci requièrent notamment que de tels drones puissent de manière sûre s’insérer et partager l’espace aérien civil moyennant le passage d’une certification de leur vol au même titre que pour les avions de transport des différentes compagnies aériennes. Dès lors, face à cet enjeu de sécurisation des vols de mini-drones, la consolidation de la connaissance de l’état de l’aéronef par des techniques d’estimation devient un tâche essentielle pour en assurer le contrôle, y compris en situations dégradées (pannes capteurs, perte occasionnelle de signaux, bruit et perturbations environnantes, imperfections des moyens de mesure, etc). Tenter de répondre à cet enjeu conduit naturellement le chercheur à s’attaquer à des problèmes relativement nouveaux, en tout cas pas forcément aussi proches de ceux qui se posent dans le secteur de l’aéronautique civile ou militaire, où le système avionique est sans commune mesure avec celui sur lequel nous avons travaillé dans cette thèse. Ce travail à tout d’abord consisté à définir une modélisation dynamique descriptive du vol des mini-drones étudiés, suffisamment générique pour être appliquée à différents types de minidrones (voilure fixe, multirotor, etc). Par la suite, deux algorithmes d’estimation originaux, dénommés IUKF et -IUKF, exploitant ce modèle, ont été développés avant d’être testés en simulation puis sur données réelles pour la version -IUKF. Ces deux méthodes transposent le cadre générique des observateurs invariants au cas de l’estimation non linéaire de l’état d’un système dynamique par une technique de type Unscented Kalman Filter (UKF) qui appartient à la classe plus générale des algorithmes de filtrage non linéaire de type Sigma Point (SP). La solution proposée garantit un plus grand domaine de convergence de l’estimé que les techniques plus traditionnelles. / This thesis presents the study of an algorithmic solution for state estimation problem of unmanned aerial vehicles, or UAVs. The necessary resort to multiple miniaturized low-cost and low-performance sensors integrated into mini-RPAS, which are obviously subjected to hardspace requirements or electrical power consumption constraints, has led to an important interest to design nonlinear observers for data fusion, unmeasured systems state estimation and/or flight path reconstruction. Exploiting the capabilities of nonlinear observers allows, by generating consolidated signals, to extend the way mini-RPAS can be controlled while enhancing their intrinsic flight handling qualities.That is why numerous recent research works related to RPAS certification and integration into civil airspace deal with the interest of highly robust estimation algorithm. Therefore, the development of reliable and performant aided-INS for many nonlinear dynamic systems is an important research topic and a major concern in the aerospace engineering community. First, we have proposed a novel approach for nonlinear state estimation, named pi-IUKF (Invariant Unscented Kalman Filter), which is based on both invariant filter estimation and UKF theoretical principles. Several research works on nonlinear invariant observers have been led and provide a geometrical-based constructive method for designing filters dedicated to nonlinear state estimation problems while preserving the physical properties and systems symmetries. The general invariant observer guarantees a straightforward form of the nonlinear estimation error dynamics whose properties are remarkable. The developed pi-IUKF estimator suggests a systematic approach to determine all the symmetry-preserving correction terms, associated with a nonlinear state-space representation used for prediction, without requiring any linearization of the differential equations. The exploitation of the UKF principles within the invariant framework has required the definition of a compatibility condition on the observation equations. As a first result, the estimated covariance matrices of the pi-IUKF converge to constant values due to the symmetry-preserving property provided by the nonlinear invariant estimation theory. The designed pi-IUKF method has been successfully applied to some relevant practical problems such as the estimation of Attitude and Heading for aerial vehicles using low-cost AH reference systems (i.e., inertial/magnetic sensors characterized by low performances). In a second part, the developed methodology is used in the case of a mini-RPAS equipped with an aided Inertial Navigation System (INS) which leads to augment the nonlinear state space representation with both velocity and position differential equations. All the measurements are provided on board by a set of low-cost and low-performance sensors (accelerometers, gyrometers, magnetometers, barometer and even Global Positioning System (GPS)). Our designed pi-IUKF estimation algorithm is described and its performances are evaluated by exploiting successfully real flight test data. Indeed, the whole approach has been implemented onboard using a data logger based on the well-known Paparazzi system. The results show promising perspectives and demonstrate that nonlinear state estimation converges on a much bigger set of trajectories than for more traditional approaches.
176

Search Strategies For Multiple Autonomous Agents

Sujit, P B 10 1900 (has links) (PDF)
No description available.
177

Stratégies de mobilité optimisées pour la tolérance aux perturbations dans les réseaux sans fil / Designing optimized and disruption-tolerant mobility strategies for wireless networks

Reynaud, Laurent 30 March 2017 (has links)
L'objectif de cette thèse est de proposer des stratégies d'optimisation protocolaire et architecturale adaptées aux cas d'usages pour lesquels les communications entre les noeuds d'un réseau sont susceptibles d'être fortement perturbées par des conditions de déploiement défavorables, sans que les mécanismes standards de réparation de panne prévus pour ce réseau puissent convenablement traiter et résorber les effets de ces perturbations. Il peut s'agir de divers contextes applicatifs, comme celui des réseaux de communication d'urgence, mis en oeuvre suite à la survenue de désastres ou plus généralement d'incidents non planifiés capables de laisser les réseaux d'une zone affectée partiellement ou totalement endommagés. Les perturbations mentionnées peuvent être de différente nature : elles peuvent par exemple être provoquées par un dimensionnement du réseau défavorable (ex. nombre de noeuds trop faible, surface de dispersion des nœuds trop importante, portée des interfaces de communication sans fil trop réduites, . . . en regard des autres paramètres de déploiement considérés). Elles peuvent aussi être provoquées par des causes externes, comme par exemple la présence non anticipée d'obstacles ou la survenue de sources d'interférences extérieures au réseau considéré. De manière générale, on constate qu'en présence de telles perturbations, un réseau non conçu pour spécifiquement fonctionner dans de telles conditions peut voir ses performances et la qualité d'expérience de ses utilisateurs baisser significativement. Dans ce contexte, nous cherchons à comparer la perception que nous avons traditionnellement de la mobilité dans les réseaux sans fil, en particulier dans les réseaux ad hoc mobiles et les réseaux tolérants aux perturbations et aux délais, avec les principes de la mobilité contrôlée, selon lesquels un noeud est capable de participer directement à la détermination de sa trajectoire et à la réalisation de son déplacement. Nous définissons un système de forces virtuelles, comprenant diverses composantes répulsives, attractives, de frottement et d'alignement, pouvant être appliquées aux noeuds d'un réseau. Nous expliquons ensuite comment concrètement utiliser ces forces virtuelles dans un déploiement réseau, et nous spécifions une solution protocolaire utilisée selon diverses variations, que nous mettons en oeuvre à travers des stratégies de mobilité contrôlée adaptées à différents environnements réseau.Nous prenons tout d'abord appui sur un scénario applicatif relatif à la lutte contre la progression d'une espèce invasive, le frelon asiatique, et décrivons un déploiement sur un réseau ad hoc sans fil reposant sur un ensemble de véhicules mobiles aériens qui exécutent une première stratégie de mobilité contrôlée. Nous cherchons à identifier les plages de valeurs pour les paramètres-clés de notre protocole à base de forces virtuelles aboutissant aux meilleures performances du réseau constitué par l'ensemble des noeuds considérés. Par la suite, nous introduisons également un scénario de déploiement de réseau temporaire de secours en situation de désastre, toujours de type ad hoc sans fil, puis nous présentons une analyse de la performance d'une seconde stratégie de mobilité contrôlée adaptée à cet environnement. Nous montrons en particulier comment cette stratégie se comporte lorsque le nombre de noeuds du réseau augmente. Nous abordons ensuite le contexte des réseaux utilisés en conditions défavorables et des mécanismes de tolérance aux perturbations. Nous cherchons ici à concevoir un troisième type de stratégie de mobilité contrôlée utilisant conjointement des mécanismes de tolérance aux perturbations et aux délais et les principes de mobilité contrôlée afin d'augmenter significativement les performances du réseau / Throughout this thesis, we seek to propose and design optimized strategies that are adapted to a widespread class of use cases in which communications between network nodes may be disrupted by adverse deployment conditions, assuming that standard fault repair mechanisms are unable to address and mitigate the effects created by these disruptions. Such use cases include the applicative context of emergency communication networks, which are often met in the wake of disasters, or more generally after the occurrence of any unexpected event which may leave the existing networks of an affected area partially or even totally damaged. The aforementioned disruptions can be of different nature: they may result from a detrimental network dimensioning (e.g. low number of network nodes, excessive node scattering surface, insufficient radio communication range, . . . with respect to the other considered deployment parameter values). They may also stem from external causes, e.g. the unexpected presence of obstacles on the area of interest, or the existence of extrinsic interference sources that may disturb the considered network. In general, it can be observed that given such disruptions, a network which is not inherently designed to operate in these conditions is likely to under-perform and, as a result, to offer a significantly decreased quality of experience to its users. In this regard, we seek to compare our perception of the traditional concept of mobility as seen in common infrastructure, ad hoc or disruption- and delay-tolerant wireless networks with the principles of controlled mobility, according to which a network node may directly control its own movement and affect its trajectory accordingly. More precisely, we investigate the means to define a virtual force system which encompasses multiple repulsive, attractive, friction and alignment forces, all of which may be applied to network nodes in order to enforce this principle of controlled mobility.We then explain how virtual forces can concretely be implemented and used in a realistic network deployment, and we specify a protocol solution and its variations, which we enforce within controlled mobility strategies with the prospect that those prove best suited to the considered network environments. We first take as an applicative background a scenario aiming to fight the spread of an invasive species, the Asian hornet, and we outline a practical deployment relying on a wireless ad hoc network formed with unmanned aerial nodes which all enforce our first proposed controlled mobility strategy. We then seek to identify the best value intervals for the key parameters of our virtual force-based protocol, anticipating that configured with these values, the deployed network will yield its best performance in terms of delays and packet delivery. Later, we introduce a scenario related to the deployment of an emergency communication network, still on the basis of wireless ad hoc network principles. We then present an analysis of how a second proposed controlled mobility strategy performs in this applicative environment. In particular, we show how this strategy behaves when the number of network nodes increases. At that point, we address the context of networks deployed in challenging conditions, and of the use of disruption- and delaytolerant mechanisms. We aim here at designing a third type of strategy that jointly uses disruption- and delay-tolerant mechanisms as well as controlled mobility principles, in order to significantly increase the overall network performance. We then investigate and explain how this strategy allows transmitting a fraction of the user traffic with short delays, when an end-to-end route is available along a communication chain, while the other fraction of the traffic is delivered with longer delays, with the support of delay-tolerant routing mechanisms
178

Controles topográficos en pendientes pronunciadas para evitar deslizamientos utilizando vehículos aéreos no tripulados (UAV) / Topographic control son steep slopes to prevent landslides using unmanned aerial vehicles (UAV)

Gibaja Bautista, Roberto Sebastian, Rojas Ruiz, Rodrigo David 18 August 2019 (has links)
El siguiente trabajo de investigación se realizó en la bajada de Armendáriz, acantilado de la Costa Verde, distrito de Miraflores, provincia de Lima, Perú. En este se propone la creación de una metodología de control topográfico en la zona anteriormente mencionada, esto debido a que se presentan constantes deslizamientos de rocas por diversos factores como la erosión marina y el tránsito vehicular cercano. Usando información del Instituto Geográfico Nacional (IGN), información brindada por profesionales en el área e información obtenida del vuelo fotogramétrico con dron Mavic 2 Pro realizado, se elaboró la comparación de perfiles longitudinales de los años 2019, 2020 y 2021 en una zona del talud que sufre deslizamientos de manera constante. Con el fin de mantener la precisión y coherencia de los resultados, se procesó la información obtenida para lograr las mismas características entre los planos de curvas de nivel que sirvieron para la realización de los cálculos y el posterior análisis. Entre los principales resultados obtenidos se determinó que la parte superior del talud se redujo 1.30 m durante los años evaluados, la parte media una reducción de 0.50 m y la parte inferior un incremento de 1.20 m. Con los resultados mencionados anteriormente se determinó la tendencia a sufrir derrumbes que posee la zona del talud evaluada y se propuso la realización de vuelos fotogramétricos anuales para el seguimiento del comportamiento del talud con el fin de implementar obras de ingeniería de contención en las zonas vulnerables. / The following research work was carried out in the Bajada de Armendariz, cliff of the Costa Verde, district of Miraflores, province of Lima, Peru. In this, the creation of a topographic control methodology in the aforementioned area is proposed, due to the fact that there are constant rock slides due to various factors such as marine erosion and nearby vehicular traffic. Using information from the National Geographic Institute (IGN), information provided by professionals in the area and information obtained from the photogrammetric flight with a Mavic 2 Pro drone carried out. the comparison of longitudinal profiles of the years 2019, 2020 and 2021 in an area of ​​the slope was elaborated that suffers landslides constantly. In order to maintain the precision and coherence of the results, the information obtained was processed to achieve the same characteristics between the contour planes that were used to carry out the calculations and the subsequent analysis. Among the main results obtained, it was determined that the upper part of the slope decreased 1.30 m during the evaluated years, the middle part a reduction of 0.50 m and the lower part an increase of 1.20 m. With the aforementioned results, the tendency to collapse in the area of ​​the evaluated slope was determined and it was proposed to carry out annual photogrammetric flights to monitor the behavior of the slope in order to implement containment engineering works in vulnerable areas. / Trabajo de investigación
179

Development of Adaptive Computational Algorithms for Manned and Unmanned Flight Safety

Elkin, Colin P. January 2018 (has links)
No description available.
180

Diseño de nuevos algoritmos de guiado y navegación con evasión de colisiones para vehículos aéreos no tripulados.

Samaniego Riera, Franklin Eduardo 15 February 2021 (has links)
Tesis por compendio / [ES] Debido a la creciente popularidad sobre la variedad de los Vehículos No Tripulados tanto en el campo militar como en el comercial, y de sus capacidades para navegar por diversos entornos, ya sean terrestres, aéreos o marinos, se evidencia que la clásica planificación de trayectorias y movimientos bidimensionales 2D podría no ser suficiente en un futuro inmediato. De esta manera, se debe resaltar que el presente trabajo aborda el problema de los Vehículos Aéreos No Tripulados (UAVs) de ala fija. En este sentido, la necesidad de encontrar una trayectoria navegable en el espacio euclídeo 3D se hace cada vez más necesario. En el caso de los UAV, considerar su cinemática para generar trayectorias suaves en tres dimensiones puede tener un interés significativo para la navegación autónoma aérea. Finalmente, los beneficios adicionales que se pueden producir son importantes. La principal dificultad de este problema es que los vehículos aéreos de características no-holonómicas se ven obligados a avanzar sin la posibilidad de detenerse a través de trayectorias 3D con curvaturas limitadas. En este sentido, se ha investigado la manera de proporcionar una completa caracterización de trayectorias óptimas para UAVs con un radio de giro limitado que se mueve en el plano tridimensional a una velocidad constante. Para completar tales tareas, un planificador de trayectorias no sólo debe proporcionar rutas tridimensionales para alcanzar una posición de destino sin colisionar con obstáculos, sino también debe asegurar que tal trayectoria sea adecuada para los UAVs que poseen propiedades cinemáticas específicas. Por lo tanto, el desarrollo del trabajo ha completado la algoritmia que genera una trayectoria discreta tridimensional al definir un conjunto de puntos 3D, resultantes de una división del espacio euclídeo tridimensional de manera dinámica, determinando las mejores opciones de avance, evitando analizar cada espacio del entorno completo. De esta manera, partiendo de los puntos 3D resultantes de la planificación de trayectoria tridimensional, se ha generado una trayectoria en forma de curva suave construida en función de las limitaciones de giro del UAV (resaltando que es difícil asegurar que el camino resultante cumpla con las restricciones cinemáticas en las tres dimensiones simultáneamente). Finalmente, es importante destacar que a menudo las restricciones mencionadas se calculan secuencialmente y de forma bidimensional, sobre un par de dimensiones desacopladas, lo que limita la capacidad de optimización. Para todo ello, se ha desarrollado un algoritmo de suavizado para un planificador de trayectorias que considera las restricciones cinemáticas tridimensionales completas sin desacoplar las dimensiones. / [CA] Debut a la creixent popularitat sobre la varietat dels Vehicles No Tripulats tant en el camp militar com en el comercial, i de les seves capacitats per navegar per diversos entorns, ja siguin terrestres, aeris o marins, s'evidencia que la clàssica planificació de trajectòries i moviments bidimensionals 2D podria no ser suficient en un futur immediat. D'aquesta manera, s'ha de ressaltar que el present treball aborda el problema dels Vehicles Aeris No Tripulats (UAV) d'ala fixa. En aquest sentit, la necessitat de trobar una trajectòria navegable en l'espai euclidià 3D es fa cada vegada més necessari. En el cas dels UAV, considerar la seva cinemàtica per generar trajectòries suaus en tres dimensions pot tenir un interès significatiu per a la navegació autònoma aèria. Finalment, els beneficis addicionals que es poden produir són importants. La principal dificultat d'aquest problema és que els vehicles aeris de característiques no-holonómicas es veuen obligats a avançar sense la possibilitat de detenir-se a través de trajectòries 3D amb curvatures limitades. En aquest sentit, s'ha investigat la manera de proporcionar una completa caracterització de trajectòries òptimes per UAVs amb un radi de gir limitat que es mou en el pla tridimensional a una velocitat constant. Per completar aquestes tasques, un planificador de trajectòries no només ha de proporcionar rutes tridimensionals per assolir una posició de destinació sense col·lisionar amb obstacles, sinó també ha d'assegurar que tal trajectòria sigui adequada per als UAVs que posseeixen propietats cinemàtiques específiques. Per tant, el desenvolupament de la feina ha completat la algorísmia que genera una trajectòria discreta tridimensional a l'definir un conjunt de punts 3D, resultants d'una divisió de l'espai euclidià tridimensional de manera dinàmica, determinant les millors opcions d'avanç, evitant analitzar cada espai de l' entorn complet. D'aquesta manera, partint dels punts 3D resultants de la planificació de trajectòria tridimensional, s'ha generat una trajectòria en forma de corba suau construïda en funció de les limitacions de gir de l'UAV (ressaltant que és difícil assegurar que el camí resultant compleixi amb les restriccions cinemàtiques en les tres dimensions simultàniament). Finalment, és important destacar que sovint les restriccions esmentades es calculen seqöencialment i de forma bidimensional, sobre un parell de dimensions desacoblades, el que limita la capacitat d'optimització. Per tot això, s'ha desenvolupat un algoritme de suavitzat per a un planificador de trajectòries que considera les restriccions cinemàtiques tridimensionals completes sense desacoblar les dimensions. / [EN] Due to the growing popularity of the variety of Unmanned Vehicles in both the military and commercial fields, and their capabilities to navigate diverse environments, whether land, air or sea, it is evident that the classic two-dimensional 2D trajectory and motion planning may not be enough in the near future. Thus, it should be noted that this paper addresses the problem of fixed-wing Unmanned Aerial Vehicles (UAVs). In this sense, the need to find a navigable path in 3D Euclidean space becomes more and more necessary. In the case of UAVs, considering their kinematics to generate smooth trajectories in three dimensions may be of significant interest for autonomous air navigation. Finally, the additional benefits that can be produced are important. The main difficulty of this problem is that air vehicles with non-holonomic characteristics are forced to advance without the possibility of stopping through 3D trajectories with limited curvatures. In this regard, research has been conducted to provide a complete characterization of optimal trajectories for UAVs with a limited turning radius that move in the 3D plane at a constant speed. To complete such tasks, a path planner must not only provide three-dimensional paths to reach a target position without colliding with obstacles, but must also ensure that such a path is suitable for UAVs that possess specific kinematic properties. Therefore, the development of the work has completed the algorithm that generates a discrete three-dimensional path by defining a set of 3D points, resulting from a division of the three-dimensional Euclidean space in a dynamic way, determining the best forward options, avoiding to analyze each space of the whole environment. In this way, starting from the 3D points resulting from the three-dimensional path planning, a smooth curve path has been generated, built according to the UAV turning constraints (highlighting that it is difficult to ensure that the resulting path meets the kinematic constraints in the three dimensions simultaneously). Finally, it is important to note that often the constraints mentioned are calculated sequentially and in a two-dimensional shape, on a pair of decoupled dimensions, which limits the ability to optimize. For all this, a smoothing algorithm has been developed for a path planner that considers the complete three-dimensional kinematic constraints without decoupling the dimensions. / Este trabajo ha sido parcialmente financiado por el Gobierno de España a través del Ministerio de Economía y Competitividad bajo el proyecto de Investigación DP I2015−71443−R, y por la administración local de la Generalitat Valenciana a través de los proyectos GV /2017/029 y AICO/2019/055. El autor ha sido beneficiario de una beca otorgada por el Instituto de Fomento al Talento Humano (IFTH) (2015−AR2Q9209) a través del Gobierno de Ecuador. / Samaniego Riera, FE. (2021). Diseño de nuevos algoritmos de guiado y navegación con evasión de colisiones para vehículos aéreos no tripulados [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/161274 / Compendio

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