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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.
21

Mobilní robotická platforma řízená pomocí PLC / PLC Control of Mobile Robotics Platform

Konečný, Michael January 2020 (has links)
The aim of this master's thesis was to create a design for a prototype of a mobile robotic platform and its physical fabrication. Another goal of this master's thesis was to develop a control algorithm and its implementation into a prototype. In addition, the thesis was extended by an autonomous motion mode, an algorithm for robot path planning, and the design of the Human Machine Interface (HMI). The introduction contains a description of some already created mobile robotic platforms, a presentation of the company B&R and the theory needed to understand omnidirectional mobility. The next chapters describe the design and construction of a prototype with a selection of electronic components and their wiring, implementation of an algorithm for robot path planning, implementation of a control algorithm and design, together with the implementation of the user environment. At the end of this master's thesis, the possibilities of extending the project to future years are described.
22

Zpracování obrazu na platformě Raspberry Pi pro mobilní robotiku / Image processing on Raspberry Pi platform for mobile robotics

Kapitančik, Maroš January 2016 (has links)
This thesis deals with developing of image processing algorithm for robots controlled by informations taken from visual system. Core of the used system constitutes low-budget platform Raspberry Pi. Before the development of algorithm there is a series of test for image processing which discovers possibilities of used platform. Problem solution is divided to several parts. Limited performance frequently leads to individual problem solving. Afterall is shown sensitivity and performance analysis of developed solution.
23

On Cooperative Surveillance, Online Trajectory Planning and Observer Based Control

Anisi, David A. January 2009 (has links)
The main body of this thesis consists of six appended papers. In the  first two, different  cooperative surveillance problems are considered. The second two consider different aspects of the trajectory planning problem, while the last two deal with observer design for mobile robotic and Euler-Lagrange systems respectively.In Papers A and B,  a combinatorial optimization based framework to cooperative surveillance missions using multiple Unmanned Ground Vehicles (UGVs) is proposed. In particular, Paper A  considers the the Minimum Time UGV Surveillance Problem (MTUSP) while Paper B treats the Connectivity Constrained UGV Surveillance Problem (CUSP). The minimum time formulation is the following. Given a set of surveillance UGVs and a polyhedral area, find waypoint-paths for all UGVs such that every point of the area is visible from  a point on a waypoint-path and such that the time for executing the search in parallel is minimized.  The connectivity constrained formulation  extends the MTUSP by additionally requiring the induced information graph to be  kept recurrently connected  at the time instants when the UGVs  perform the surveillance mission.  In these two papers, the NP-hardness of  both these problems are shown and decomposition techniques are proposed that allow us to find an approximative solution efficiently in an algorithmic manner.Paper C addresses the problem of designing a real time, high performance trajectory planner for an aerial vehicle that uses information about terrain and enemy threats, to fly low and avoid radar exposure on the way to a given target. The high-level framework augments Receding Horizon Control (RHC) with a graph based terminal cost that captures the global characteristics of the environment.  An important issue with RHC is to make sure that the greedy, short term optimization does not lead to long term problems, which in our case boils down to two things: not getting into situations where a collision is unavoidable, and making sure that the destination is actually reached. Hence, the main contribution of this paper is to present a trajectory planner with provable safety and task completion properties. Direct methods for trajectory optimization are traditionally based on a priori temporal discretization and collocation methods. In Paper D, the problem of adaptive node distribution is formulated as a constrained optimization problem, which is to be included in the underlying nonlinear mathematical programming problem. The benefits of utilizing the suggested method for  online  trajectory optimization are illustrated by a missile guidance example.In Paper E, the problem of active observer design for an important class of non-uniformly observable systems, namely mobile robotic systems, is considered. The set of feasible configurations and the set of output flow equivalent states are defined. It is shown that the inter-relation between these two sets may serve as the basis for design of active observers. The proposed observer design methodology is illustrated by considering a  unicycle robot model, equipped with a set of range-measuring sensors. Finally, in Paper F, a geometrically intrinsic observer for Euler-Lagrange systems is defined and analyzed. This observer is a generalization of the observer proposed by Aghannan and Rouchon. Their contractivity result is reproduced and complemented  by  a proof  that the region of contraction is infinitely thin. Moreover, assuming a priori bounds on the velocities, convergence of the observer is shown by means of Lyapunov's direct method in the case of configuration manifolds with constant curvature. / QC 20100622 / TAIS, AURES
24

Online trajectory planning and observer based control

Anisi, David A. January 2006 (has links)
<p>The main body of this thesis consists of four appended papers. The first two consider different aspects of the trajectory planning problem, while the last two deal with observer design for mobile robotic and Euler-Lagrange systems respectively.</p><p>The first paper addresses the problem of designing a real time, high performance trajectory planner for aerial vehicles. The main contribution is two-fold. Firstly, by augmenting a novel safety maneuver at the end of the planned trajectory, this paper extends previous results by having provable safety properties in a 3D setting. Secondly, assuming initial feasibility, the planning method is shown to have finite time task completion. Moreover, in the second part of the paper, the problem of simultaneous arrival of multiple aerial vehicles is considered. By using a time-scale separation principle, one is able to adopt standard Laplacian control to this consensus problem, which is neither unconstrained, nor first order.</p><p>Direct methods for trajectory optimization are traditionally based on<i> a</i> <i>priori </i>temporal discretization and collocation methods. In the second paper, the problem of adaptive node distribution is formulated as a constrained optimization problem, which is to be included in the underlying nonlinear mathematical programming problem. The benefits of utilizing the suggested method for online trajectory optimization are illustrated by a missile guidance example.</p><p>In the third paper, the problem of active observer design for an important class of non-uniformly observable systems, namely mobile robotics systems, is considered. The set of feasible configurations and the set of output flow equivalent states are defined. It is shown that the inter-relation between these two sets may serve as the basis for design of active observers. The proposed observer design methodology is illustrated by considering a unicycle robot model, equipped with a set of range-measuring sensors.</p><p>Finally, in the fourth paper, a geometrically intrinsic observer for Euler-Lagrange systems is defined and analyzed. This observer is a generalization of the observer recently proposed by Aghannan and Rouchon. Their contractivity result is reproduced and complemented by a proof that the region of contraction is infinitely thin. However, assuming <i>a</i> <i>priori </i>bounds on the velocities, convergence of the observer is shown by means of Lyapunov's direct method in the case of configuration manifolds with constant curvature.</p>
25

Localisation et cartographie simultanées en environnement extérieur à partir de données issues d'un radar panoramique hyperfréquence / Simultaneous localization and mapping in extensive outdoor environments from hyper-frequency radar measurements

Gérossier, Franck 05 June 2012 (has links)
Le SLAM, « Simultaneous Localisation And Mapping », représente à l'heure actuelle l'une des principales thématiques investiguées dans le domaine des robots mobiles autonomes. Il permet, à l'aide de capteurs extéroceptifs (laser, caméra, radar, etc.) et proprioceptifs (odomètre, gyromètre, etc.), de trouver l'orientation et la localisation d'un robot dans un environnement extérieur vaste, inconnu ou modifié, avec la possibilité de créer une carte au fur et à mesure des déplacements du véhicule. Les travaux de thèse décrits dans ce manuscrit s'intègrent dans ce courant de recherche. Ils visent à développer un SLAM innovant qui utilise un radar à modulation de fréquence continue « FMCW » comme capteur extéroceptif. Ce capteur est insensible aux conditions climatiques et possède une portée de détection importante. Néanmoins, c'est un capteur tournant qui, dans une utilisation mobile, va fournir des données corrompues par le déplacement du véhicule. Pour mener à bien ces travaux, nous avons proposés différentes contributions : une correction de la distorsion par l'utilisation de capteurs proprioceptifs ; le développement d'une technique de localisation et cartographie simultanées nommée RS-SLAM-FMT qui effectue un scan matching sur les observations et utilise un algorithme estimatif de type EKF-SLAM ; l'utilisation, pour la première fois en SLAM, de la mise en correspondance par Transformée de Fourier-Mellin pour réaliser l'opération de scan matching ; la création d'un outil expérimental pour déterminer la matrice de covariance associée aux observations ; des tests de robustesse de l'algorithme dans des conditions d'utilisation réelles : dans des zones avec un faible nombre de points d'intérêts, sur des parcours effectués à vitesse élevée, dans des environnements péri-urbains avec une forte densité d'objets mobiles ; la réalisation d'une application temps réel pour le test du procédé sur un véhicule d'exploration qui se déplace dans un environnement extérieur vaste. / Simultaneous Localization And Mapping (SLAM) is one of the main topics investigated in the field of autonomous mobile robots. It permits the Localization and mapping of a robot in a large outdoor environment, using exteroceptive (laser, camera, radar, etc.) and proprioceptive (odometer, gyroscope, etc.) sensors. The objective of this PhD thesis is to develop innovative SLAM that uses a radar frequency modulated continuous wave (FMCW) as an exteroceptive sensor. Microwave radar provides an alternative solution for environmental imaging and overcomes the shortcomings of laser, video and sonar sensors such as their high sensitivity to atmospheric conditions. However, data obtained with this rotating range sensor is adversely affected by the vehicle’s own movement. In order to efficiently manage the work, we propose : a correction, on-the-fly, of the rotating distortion with an algorithm that uses the proprioceptive sensors’ measurements ; development of a new technique for simultaneous localization and mapping named RS-SLAM-FMT ; for the first time in SLAM, the use of the Fourier-Mellin Transform provides an accurate and efficient way of computing the rigid transformation between consecutive scans ; creation of an experimental tool to determine the covariance matrix associated with the observations. It is based on an uncertainty analysis of a Fourier-Mellin image registration ; tests of the robustness of the SLAM algorithm in real-life conditions : in an environment containing a small number of points of interest, in real full speed driving conditions, in peri-urban environments with a high density of moving objects etc. ; creation and experiment of a real-time RS-SLAM-FMT implemented on a mobile exploration vehicle in an extensive outdoor environment.
26

Perception de l'environnement par radar hyperfréquence. Application à la localisation et la cartographie simultanées, à la détection et au suivi d'objets mobiles en milieu extérieur / Perception of the environment with a hyper-frequency radar. Application to simultaneous localization and mapping, to detection and tracking of moving objects in outdoor environment.

Vivet, Damien 05 December 2011 (has links)
Dans le cadre de la robotique mobile extérieure, les notions de perception et de localisation sont essentielles au fonctionnement autonome d’un véhicule. Les objectifs de ce travail de thèse sont multiples et mènent vers un but de localisation et de cartographie simultanée d’un environnement extérieur dynamique avec détection et suivi d’objet mobiles (SLAMMOT) à l’aide d’un unique capteur extéroceptif tournant de type radar dans des conditions de circulation dites "réalistes", c’est-à-dire à haute vitesse soit environ 30 km/h. Il est à noter qu’à de telles vitesses, les données acquises par un capteur tournant son corrompues par le déplacement propre du véhicule. Cette distorsion, habituellement considérée comme une perturbation, est analysée ici comme une source d’information. Cette étude vise également à évaluer les potentialités d’un capteur radar de type FMCW (onde continue modulée en fréquence) pour le fonctionnement d’un véhicule robotique autonome. Nous avons ainsi proposé différentes contributions : – une correction de la distorsion à la volée par capteurs proprioceptifs qui a conduit à une application de localisation et de cartographie simultanées (SLAM), – une méthode d’évaluation de résultats de SLAM basées segment, – une considération de la distorsion des données dans un but proprioceptif menant à une application SLAM, – un principe d’odométrie fondée sur les données Doppler propres au capteur radar, – une méthode de détection et de pistage d’objets mobiles : DATMO avec un unique radar. / In outdoor robotic context, notion of perception and localization is essential for an autonomous navigation of a mobile robot. The objectives of this PhD are multiple and tend to develop a simultaneous localization and mapping approach in a dynamic outdoor environment with detection and tracking of moving objects (SLAMMOT) with a unique exteroceptive radar sensor in real driving conditions, around 30 km/h. At such high speed, data obtained with a rotating range sensor are corrupted by the own vehicle displacement. This distortion, usually considered as a disturbance, is analyzed here as a source of information. This study explores radar frequency modulated continuous wave (FMCW) technology potential for mobile robotics in extended outdoor environment. In this work, we propose : – a distortion correction on-the-fly with proprioceptive sensors in order to realize a localization and mapping application (SLAM), – a line based SLAM evaluation method, – a consideration of distortion in a proprioceptive purpose for localization and mapping, – an odometry principle based on Doppler velocimetry provided by radar sensor, – a detection and tracking of mobile objects : DATMO, with a unique radar sensor.
27

Online trajectory planning and observer based control

Anisi, David A. January 2006 (has links)
The main body of this thesis consists of four appended papers. The first two consider different aspects of the trajectory planning problem, while the last two deal with observer design for mobile robotic and Euler-Lagrange systems respectively. The first paper addresses the problem of designing a real time, high performance trajectory planner for aerial vehicles. The main contribution is two-fold. Firstly, by augmenting a novel safety maneuver at the end of the planned trajectory, this paper extends previous results by having provable safety properties in a 3D setting. Secondly, assuming initial feasibility, the planning method is shown to have finite time task completion. Moreover, in the second part of the paper, the problem of simultaneous arrival of multiple aerial vehicles is considered. By using a time-scale separation principle, one is able to adopt standard Laplacian control to this consensus problem, which is neither unconstrained, nor first order. Direct methods for trajectory optimization are traditionally based on a priori temporal discretization and collocation methods. In the second paper, the problem of adaptive node distribution is formulated as a constrained optimization problem, which is to be included in the underlying nonlinear mathematical programming problem. The benefits of utilizing the suggested method for online trajectory optimization are illustrated by a missile guidance example. In the third paper, the problem of active observer design for an important class of non-uniformly observable systems, namely mobile robotics systems, is considered. The set of feasible configurations and the set of output flow equivalent states are defined. It is shown that the inter-relation between these two sets may serve as the basis for design of active observers. The proposed observer design methodology is illustrated by considering a unicycle robot model, equipped with a set of range-measuring sensors. Finally, in the fourth paper, a geometrically intrinsic observer for Euler-Lagrange systems is defined and analyzed. This observer is a generalization of the observer recently proposed by Aghannan and Rouchon. Their contractivity result is reproduced and complemented by a proof that the region of contraction is infinitely thin. However, assuming a priori bounds on the velocities, convergence of the observer is shown by means of Lyapunov's direct method in the case of configuration manifolds with constant curvature. / QC 20101108

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