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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.
561

From a Synthetic Auto-Biographical Memory toward the Emergence of Different Levels of Self : a Case Study with the iCub Humanoid Robot / Depuis une mémoire autobiographique synthétique à l'émergence de différents niveaux de soi : étude de cas chez le robot humanoïde iCub

Pointeau, Grégoire 06 October 2015 (has links)
L'objectif de l'étude suivante est de déterminer l'influence de la mémoire autobiographique et de ses deux principaux composants : la mémoire épisodique et la mémoire sémantique dans l'émergence de la notion de soi. Je vais me concentrer sur la composante fonctionnelle de la mémoire autobiographique davantage que sur ses aspects anatomiques et neuronaux. Je vais ensuite décrire l'implémentation d'une mémoire autobiographique synthétique chez un robot humanoïde : l'iCub. Puis, je vais montrer comment cette mémoire synthétique peut participer avec l'aide de procédés de raisonnement, `a l'émergence d'un “soi”. Concernant cet aspect du soi, nous avons décidé de concentrer notre travail sur la définition d'Ulric Neisser de 1995 de quatre composants du soi : le “Soi Ecologique”, le “Soi Interpersonnel”, le “Soi Conceptuel” et le “Soi Etendu dans le Temps” / The objective of the following study is to define the influence of an Autobiographical Memory and its two main components : the Episodic Memory and the Semantic Memory in the emergence of the notion of “self”. I will focus on the functional part of the autobiographical memory rather that on its technical and neuronal aspect. Then I will describe the implementation of an synthetic autobiographical memory in an Humanoid Robot : the iCub. I will show how this synthetic autobiographical memory can participate with the help of several reasoning modules, in the emergence of the self. Concerning the aspect of self, we decided to work about Ulric Neisser’s four components of the self described in 1995 : the Ecological Self, the Interpersonal Self, the Conceptual Self and the Temporally Extended Self
562

Intuitive robot teleoperation based on haptic feedback and 3D visualization

Yangjun, Chen January 2016 (has links)
Robots are required in many jobs. The jobs related to tele-operation may be very challenging and often require reaching a destination quickly and with minimum collisions. In order to succeed in these jobs, human operators are asked to tele-operate a robot manually through a user interface. The design of a user interface and of the information provided in it, become therefore critical elements for the successful completion of robot tele-operation tasks. Effective and timely robot tele-navigation mainly relies on the intuitiveness provided by the interface and on the richness and presentation of the feedback given. This project investigated the use of both haptic and visual feedbacks in a user interface for robot tele-navigation. The aim was to overcome some of the limitations observed in a state of the art works, turning what is sometimes described as contrasting into an added value to improve tele-navigation performance. The key issue is to combine different human sensory modalities in a coherent way and to benefit from 3-D vision too. The proposed new approach was inspired by how visually impaired people use walking sticks to navigate. Haptic feedback may provide helpful input to a user to comprehend distances to surrounding obstacles and information about the obstacle distribution. This was proposed to be achieved entirely relying on on-board range sensors, and by processing this input through a simple scheme that regulates magnitude and direction of the environmental force-feedback provided to the haptic device. A specific algorithm was also used to render the distribution of very close objects to provide appropriate touch sensations. Scene visualization was provided by the system and it was shown to a user coherently to haptic sensation. Different visualization configurations, from multi-viewpoint observation to 3-D visualization, were proposed and rigorously assessed through experimentations, to understand the advantages of the proposed approach and performance variations among different 3-D display technologies. Over twenty users were invited to participate in a usability study composed by two major experiments. The first experiment focused on a comparison between the proposed haptic-feedback strategy and a typical state of the art approach. It included testing with a multi-viewpoint visual observation. The second experiment investigated the performance of the proposed haptic-feedback strategy when combined with three different stereoscopic-3D visualization technologies. The results from the experiments were encouraging and showed good performance with the proposed approach and an improvement over literature approaches to haptic feedback in robot tele-operation. It was also demonstrated that 3-D visualization can be beneficial for robot tele-navigation and it will not contrast with haptic feedback if it is properly aligned to it. Performance may vary with different 3-D visualization technologies, which is also discussed in the presented work.
563

Robot Navigation Using Velocity Potential Fields and Particle Filters for Obstacle Avoidance

Bai, Jin January 2015 (has links)
In this thesis, robot navigation using the Particle Filter based FastSLAM approach for obstacle avoidance derived from a modified Velocity Potential Field method was investigated. A switching controller was developed to deal with robot’s efficient turning direction when close to obstacles. The determination of the efficient turning direction is based on the local map robot derived from its on board local sensing. The estimation of local map and robot path was implemented using the FastSLAM approach. A particle filter was utilized to obtain estimated robot path and obstacles (local map). When robot sensed only obstacles, the estimated robot positions was regarding to obstacles based the measurement of the distance between the robot and obstacles. When the robot detected the goal, estimation of robot path will switch to estimation with regard to the goal in order to obtain better estimated robot positions. Both simulation and experimental results illustrated that estimation with regard to the goal performs better than estimation regarding only to obstacles, because when robot travelled close to the goal, the residual error between estimated robot path and the ideal robot path becomes monotonously decreasing. When robot reached the goal, the estimated robot position and the ideal robot position converge. We investigated our proposed approach in two typical robot navigation scenarios. Simulations were accomplished using MATLAB, and experiments were conducted with the help of both MATLAB and LabVIEW. In simulations and experiments, the robot successfully chose efficiently turning direction to avoid obstacles and finally reached the goal.
564

Towards a distributed, embodied and computational theory of cooperative interaction / Vers une théorie de la coopération incarnée, distribuée et computationelle

Lallée, Stéphane 02 April 2012 (has links)
Les robots vont peu à peu intégrer nos foyers sous la forme d’assistants et de compagnons,humanoïdes ou non. Afin de remplir leur rôle efficacement ils devront s’adapter àl’utilisateur, notamment en apprenant de celui-ci le savoir ou les capacités qui leur fontdéfaut. Dans ce but, leur manière d’interagir doit être naturelle et évoquer les mêmesmécanismes coopératifs que ceux présent chez l’homme. Au centre de ces mécanisme setrouve le concept d’action : qu’est-ce qu’une action, comment les humains les reconnaissent,comment les produire ou les décrire ? La modélisation de toutes ces fonctionnalitésconstituera la fondation de cette thèse et permettra la mise en place de mécanismescoopératifs de plus haut niveau, en particulier les plan partagés qui permettent à plusieursindividus d’oeuvrer de concert afin d’atteindre un but commun. Finalement, je présenteraiune différence fondamentale entre la représentation de la connaissance chez l’homme etchez la machine, toujours dans le cadre de l’interaction coopérative : la dissociation possibleentre le corps d’un robot et sa cognition, ce qui n’est pas imaginable chez l’homme. Cettedissociation m’amènera notamment à explorer le « shared experience framework », unesituation dans laquelle une cognition artificielle centrale gère l’expérience partagée demultiples individus ayant chacun une identité propre. Cela m’amènera finalement àquestionner les différentes philosophies de l’esprit du point de vue de l’attribution d’unesprit à une machine et de ce que cela impliquerai quant à l’esprit humain. / Robots will gradually integrate our homes wielding the role of companions, humanoids ornot. In order to cope with this status they will have to adapt to the user, especially bylearning knowledge or skills from him that they may lack. In this context, their interactionshould be natural and evoke the same cooperative mechanisms that humans use. At thecore of those mechanisms is the concept of action: what is an action, how do humansrecognize them, how they produce or describe them? The modeling of aspects of thesefunctionalities will be the basis of this thesis and will allow the implementation of higherlevel cooperative mechanisms. One of these is the ability to handle “shared plans” whichallow two (or more) individuals to cooperate in order to reach a goal shared by all.Throughout the thesis I will attempt to make links between the human development ofthese capabilities, their neurophysiology, and their robotic implementation. As a result ofthis work, I will present a fundamental difference between the representation of knowledgein humans and machines, still in the framework of cooperative interaction: the possibledissociation of a robot body and its cognition, which is not easily imaginable for humans.This dissociation will lead me to explore the “shared experience framework, a situationwhere a central artificial cognition manages the shared knowledge of multiple beings, eachof them owning some kind of individuality. In the end this phenomenon will interrogate thevarious philosophies of mind by asking the question of the attribution of a mind to amachine and the consequences of such a possibility regarding the human mind.
565

Lifelong Exploratory Navigation : integrating planning, navigation and SLAM for autonomous mobile robots with finite resources / Navigation exploratoire au long de la vie : une approche intégrant planification, navigation, cartographie et localisation pour des robots mobiles disposant de ressources finies

Mayran de Chamisso, Fabrice 18 November 2016 (has links)
Il est fondamental pour un robot d'être capable de se déplacer de manière complètement autonome afin d'accomplir une mission qui lui a été confiée, et ce avec un budget énergétique fini, dans un laps de temps contraint et sans connaissances préalables de l’environnement. Afin d'atteindre un objectif dans le plan ou l'espace, un robot doit à minima être capable d'accomplir quatre tâches: maintenir une représentation abstraite de l'environnement (une carte), être capable de se localiser à l'intérieur de cette représentation, utiliser la représentation pour planifier des itinéraires et naviguer le long de la trajectoire prévue tout en s'adaptant aux dynamiques de l'environnement et en évitant les obstacles. Chacun de ces problèmes a été étudié par la communauté de la robotique. Cependant, ces quatre composants sont en général étudiés séparément et sont par conséquent incompatibles entre eux pour l'essentiel. De plus, étant donné qu'humains et robots ne disposent que de ressources computationelles et mémorielles finies, les algorithmes de planification, navigation et SLAM devraient être capables de fonctionner avec des données incomplètes ou compressées tout en garantissant que le ou les objectifs fixés soient atteints. Dans cette thèse, la planification, la navigation et le SLAM dans des environnements arbitrairement grands et avec des ressources computationelles et mémorielles finies sont vues comme un seul problème, créant un nouveau paradigme que nous appelons Navigation Exploratoire au long de la Vie ou Lifelong Exploratory Navigation. / One of the yet unresolved canonical problems of robotics is to have robots move completely autonomously in order to accomplish any mission they are charged with, with time and resource constraints and without prior knowledge of the environment. Reaching a goal requires the robot to perform at least four tasks: maintaining an abstract representation of the environment (map), being able to localize itself within this representation, using the representation to plan paths and navigating on the planned paths while handling dynamics of the environment and avoiding obstacles. Each of these problems has been studied extensively by the robotics community. However, the four components are usually studied separately, and as a result are mostly incompatible with each other. Additionally, since humans as well as robots have to operate with finite memory and computing resources, long running planning, navigation and SLAM algorithms may have to operate on incomplete or compressed data while guaranteeing that the goal(s) can still be reached. In this thesis, planning, navigation and SLAM in arbitrarily large environments with finite computing resources and memory are considered as one single problem, for a new bio-inspired paradigm which we call Lifelong Exploratory Navigation.
566

Apport d’un entraînement utilisant un dispositif robotisé sur la motricité du membre supérieur chez des patients présentant une hémiparésie après un accident vasculaire cérébral / Contribution of a robot-assisted training on motors skills of the upper limb in patients with hemiparesis following stroke.

Pila, Ophélie 08 November 2018 (has links)
Le syndrome de parésie spastique consécutif à un accident vasculaire cérébral (AVC) comprend plusieurs composantes dont la rétraction musculaire, la parésie sensible à l’étirement et l’hyperactivité musculaire, trois symptômes concourant à une altération de la fonction motrice du membre supérieur dans l’hémiparésie. Les progrès d’un patient atteint par ce syndrome peuvent reposer sur deux types de plasticité cérébrale : post-lésionnelle et liée à l’activité. Les maîtres-mots pour optimiser une récupération motrice par la plasticité liée à l’activité sont : intensité, répétition, effort, attention portée au mouvement, tâche dirigée vers un but et mouvement actif. Au regard des différentes techniques de rééducation, la thérapie utilisant un dispositif robotisé répond à ces principes stimulateurs de la plasticité cérébrale liée à l’activité. Cependant les modalités exactes de l’intervention robotisée et sa durée souhaitable n’ont pas été clarifiées.Une première étude rétrospective a montré que les bénéfices cliniques et cinématiques associés à l’utilisation combinée de l’ergothérapie conventionnelle et de la robot-thérapie sur au moins trois mois suggèrent l’intérêt d’une durée de traitement longue chez des patients aux limitations modérées en phase tardive de la période subaiguë. Une deuxième étude rétrospective suggère qu’à quatre ans, l’évolution lente de la fonction motrice pour ces mêmes patients semble fonction de la sévérité initiale, où finalement les moins bons régressent et les meilleurs s’améliorent un peu. Enfin, une étude prospective randomisée contrôlée en phase subaiguë a démontré que l’entraînement de mouvements sur robot sans assistance améliore l’amplitude active d’extension du coude plus que le même entraînement avec assistance au besoin, qui pourtant a permis au patient d’effectuer environ un tiers de mouvements en plus par séance. Aussi, le facteur difficulté de l’effort prévaudrait sur celui du nombre de répétitions pour stimuler la plasticité cérébrale. Ce dernier principe ne s’exprime cependant que sur le mouvement élémentaire qui est directement entraîné par le robot, en l’occurrence l’extension du coude, tandis que d’autres mouvements fondamentaux dans l’utilisation du bras humain, par exemple la flexion de l’épaule en charge, l’extension du poignet et la préhension digitale, ne sont pas exercés avec la plupart des versions actuelles des robots d’assistance à la rééducation. L’autre limite majeure de la thérapie assistée par un dispositif robotisé est qu’elle ignore la maladie musculaire présentée par les patients (rétractions), ne s’adressant qu’à la composante neurologique de la parésie spastique (parésie de l’agoniste et cocontraction de l’antagoniste). C’est ainsi que malgré le grand nombre de répétitions de mouvements qu’elle permet, nous n’avons pas constaté que la thérapie assistée par un robot se montrait plus efficace que la thérapie conventionnelle seule sur la progression de la fonction globale du membre supérieur en phase subaiguë après un AVC.Les données issues de ce travail devraient permettre aux thérapeutes ayant accès à des dispositifs robotisés d’aide à la rééducation du membre supérieur d’affiner les modalités et la durée de leur prise en charge. L’association de la thérapie assistée par robots à d’autres thérapies pourrait permettre d’optimiser la réduction des troubles moteurs dans l’hémiparésie après un AVC. / Following stroke, the syndrome of deforming spastic paresis includes several components in which three main symptoms, soft tissue contracture, stretch-sensitive paresis and spastic muscle overactivity, impede motor function. Patient progress may utilize two types of brain plasticity: lesion-induced and behavior-induced. The key notions to optimize motor recovery through behavior-induced plasticity are: repetition, effort, attention to movement, goal-directed task and active movement. Robot-assisted therapy fulfills all these conditions. However, the exact modalities of use and optimal duration are yet to be defined.From a first retrospective study, the magnitude of the clinical and kinematic benefits associated with the combined use of robot-assisted and conventional occupational therapies during three months suggest the value of a long duration treatment in the late subacute phase for moderately impaired hemiparetic patients. A second retrospective study observed the four-year long-term evolution of motor function for these patients, which appears to be related to the baseline severity, in which the more severely affected deteriorate and the less severe patients improve a little. Finally, a prospective randomized controlled study demonstrated that non-assisted movement training was associated with greater active elbow extension improvement than training with the assist-as-needed modality even though the latter offered the patient 33% movements more in each session. Therefore, the difficulty of effort appears to be a more effective factor of brain plasticity than the number of movement repetitions. This principle has however been demonstrated only for the primary movement directly trained by the robot, that is, elbow extension. The other movements that are essential in human upper limb use, such as shoulder flexion, wrist extension, gross and fine digit prehension, are not trained with the most current versions of robots used in upper limb rehabilitation. In addition, another important limitation of robot-assisted therapy is that it ignores the muscle disorder (antagonist shortening) of spastic paresis by focusing only on the neural disorder component (paresis in agonists and cocontraction in antagonists). Despite the high number of movement repetitions in robot-assisted therapy, our prospective study has not been able to show superiority of robot-assisted therapy over conventional occupational therapy in improving overall upper limb motor function in the subacute phase after stroke.The findings of this work should help therapists with access to robotic devices to refine the modalities and duration of their use in patient care. Combining robot-assisted therapy with other therapies might optimize the reduction of motor disorder in hemiparesis following stroke.
567

Robotic Construction Using Intelligent Scaffolding

Enyedy, Albert J. 18 May 2020 (has links)
Construction is a complex activity that requires the cooperation of multiple workers. Every year, construction activities cause injuries and casualties. To make construction safer, new solutions could be provided by robotics. Robots could be employed not only to replace human workers, but also to make construction in harsh environments safe and cost-effective, paving the way for enhanced underwater infrastructure, deeper underground mining, and planetary colonization. In this thesis, we focus on the topic of collective construction, which involves the cooperation of multiple robots, by presenting a collective robot construction method of our own. Collective construction can be a more viable option than employing individual, complex robots, by potentially allowing the effective realization of large structures, while offering resilience through redundancy, analogous to insect colonies. Our approach offers a novel solution in the design trade-off between choosing the number of robots involved vs. the complexity of the robots involved. On the one hand, capable and complex robots are expensive, limiting the cost effectiveness of realizing large swarms which provide redundancy and increase the system’s resilience to faults. On the other hand, simple and inexpensive robots can be manufactured in large numbers and offer high redundancy, at the cost of limited individual capa bilities and lower performance. We use two types of robots: intelligent scaffolding and worker robots. The intelligent scaffolding acts as regular scaffolding, allowing the worker robots to navigate the structure they assemble, while also guiding and monitoring the construction of the structure. The worker robots move and connect scaffolding and building material while only knowing the local commands necessary to complete their task. This approach is loosely inspired by termite mounds, in which termites use the process of stigmergy in which they mark construction pellets with pheromones to affect the progress of construction, while navigating the struc ture that they build. Thanks to intelligent scaffolding, construction robots have a simple design that allows minimalist onboard computation and communication equipment. In this thesis, we produced a minimum viable prototype demonstrating this concept. Intelligent scaffolding is realized through smart blocks that can be laid and connected to each other. The smart blocks are capable of simple computation and communication once laid. The construction robot uses local navigation methods by line-following across the scaffolding and building blocks of the system. The blocks and construction robot both have a modular design, simplifying the process of manufacturing and repairs while maintaining a low cost. The robot and blocks use magnets to increase the margin of error during block manipulation and allow for the assembly and removal of scaffolding as well as its reuse between build sites. To communicate with the robot, the intelligent scaffolding blocks send local IR signals, similar to TV remote signals, when the robot is on top of them, minimizing the risk of global interference and keeping the system portable. To monitor the connectivity of the system throughout the life cycle of the structure, electrical connections run through each of the blocks, which indicate the status of the structure and can be used to diagnose the location of breaks in the structure for maintenance.
568

Coordinated Navigation and Localization of an Autonomous Underwater Vehicle Using an Autonomous Surface Vehicle in the OpenUAV Simulation Framework

January 2020 (has links)
abstract: The need for incorporating game engines into robotics tools becomes increasingly crucial as their graphics continue to become more photorealistic. This thesis presents a simulation framework, referred to as OpenUAV, that addresses cloud simulation and photorealism challenges in academic and research goals. In this work, OpenUAV is used to create a simulation of an autonomous underwater vehicle (AUV) closely following a moving autonomous surface vehicle (ASV) in an underwater coral reef environment. It incorporates the Unity3D game engine and the robotics software Gazebo to take advantage of Unity3D's perception and Gazebo's physics simulation. The software is developed as a containerized solution that is deployable on cloud and on-premise systems. This method of utilizing Gazebo's physics and Unity3D perception is evaluated for a team of marine vehicles (an AUV and an ASV) in a coral reef environment. A coordinated navigation and localization module is presented that allows the AUV to follow the path of the ASV. A fiducial marker underneath the ASV facilitates pose estimation of the AUV, and the pose estimates are filtered using the known dynamical system model of both vehicles for better localization. This thesis also investigates different fiducial markers and their detection rates in this Unity3D underwater environment. The limitations and capabilities of this Unity3D perception and Gazebo physics approach are examined. / Dissertation/Thesis / Masters Thesis Computer Science 2020
569

Mobilní robot s GNSS navigací / GNSS Navigated Mobile Robot

Chmelař, Jakub January 2018 (has links)
The diploma thesis is focused on the topic of global satellite navigation of mobile robots. The paper describes the principle of currently available global satellite navigation systems. The main element of the thesis is the proposal of mobile robot navigation algorithm. An integral part is also the design of a mobile robot to verify the functionality of the navigation algorithm. The robot software program is described. At the end, everything is verified by real experiments.
570

Plánování cesty mobilního robotu / Mobile robot path planning

Klobušníková, Zuzana January 2018 (has links)
This master thesis deals with the planning of the robot's path using selected graph algorithms of artificial intelligence. The theoretical part describes the basic methods of planning a robot's path. It is related to the graph algorithm more closely. The practical part deals with implementation of selected graph algorithms, creation of simulation environment in Python, description and evaluation of experiments.

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