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Dissertations / Theses on the topic 'Mobile Robot'
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1
Yang, Hai. "Etude d’un système de fabrication agile mobile pour composants de grande taille." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20042/document.
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Les robots industriels, bien connus pour être des systèmes de fabrication flexibles et agiles, atteignent leurs limites lorsqu'il s'agit d'effectuer des tâches sur des pièces de grande taille (par exemple: les pièces longues et minces de l'industrie aéronautique). Pour ce type des tâches, les solutions existantes sont à leurs limites: les bras manipulateurs à base fixe souffrent d'un espace de travail trop limité; les bras manipulateurs montés sur véhicule ne sont pas assez précis; les machines-outils conventionnelles doivent être conçus à méga-échelle (plusieurs dizaines de mètres). Dans la cadre de cette thèse de doctorat, nous avons proposé des solutions robotiques innovantes qui combinent la capacité de marcher (ou de grimper) sur la pièce (ou sur le montage d'usinage) avec la capacité d'usiner. De l'analyse de la topologie et de la mobilité à la modélisation géométrique et cinématique, ainsi que la proposition d'algorithmes de contrôle innovants, des robots ont été proposés et étudiés pour la réalisation des tâches d'usinage ainsi que des tâches de locomotion. Un prototype a été construit qui témoigne de la pertinence de ce concept innovant. Il repose sur une architecture parallèle à actionnement redondant (8 moteurs pour 6 degrés de liberté) et combine moteurs, freins, dispositifs de bridage et de nombreux capteurs de position. Le prototype peut se fixer sur le montage d'usinage, réaliser ses tâches de fabrication, puis modifier sa configuration pour devenir un robot marcheur capable d'atteindre la zone de travail suivanteIndustrial robots, well known as flexible and agile manufacturing systems, reach their limits when dealing with very large workpieces (e.g.: very long and slender parts found in aeronautics industry). For such tasks, existing solutions are at their limits: stationary manipulator arms suffer from a too limited workspace; manipulators mounted on a vehicle are not accurate enough; classical machine-tools must be designed at mega-scale (several tens of meters). This thesis work aims at offering an innovative robotic solution that combines the ability to walk (or climb) on the workpiece (or on the tooling that supports the workpieces) together with manufacturing ability. From the topology and mobility analysis to the geometrics and kinematics modeling, as well as innovative control algorithms proposition, the proposed mobile manufacturing robots have been studied for achieving both machining and locomotion tasks. A prototype has been built to show the concept effectiveness . It is based on a parallel mechanism with actuation redundancy (8 motors for 6 degrees-of-freedom), combining motors, brakes, clamping devices and numerous position sensors. The robot can clamp itself on the manufacturing tooling, and then change its configuration to become a walking robot able to reach the next working area
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Luh, Cheng-Jye 1960. "Hierarchical modelling of mobile, seeing robots." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276998.
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This thesis describes the implementation of a hierarchical robot simulation environment which supports the design of robots with vision and mobility. A seeing robot model applies a classification expert system for visual identification of laboratory objects. The visual data acquisition algorithm used by the robot vision system has been developed to exploit multiple viewing distances and perspectives. Several different simulations have been run testing the visual logic in a laboratory environment. Much work remains to integrate the vision system with the rest of the robot system.
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Baba, Akihiko. "Robot navigation using ultrasonic feedback." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=677.
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Thesis (M.S.)--West Virginia University, 1999.Title from document title page. Document formatted into pages; contains viii, 122 p. : ill. Includes abstract. Includes bibliographical references (p. 57-59).
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Cheng, Sheri A. (Sheri Ann) 1977. "Mobile robot relocation." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/91353.
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Sorour, Mohamed. "Motion discontinuity-robust controller for steerable wheeled mobile robots." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTS090/document.
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Les robots mobiles à roues orientables gagnent de la mobilité en employant des roues conventionnelles entièrement orientables, comportant deux joints actifs, un pour la direction et un autre pour la conduite. En dépit d'avoir seulement un degré de mobilité (DOM) (défini ici comme degrés de liberté instantanément autorisés DOF), correspondant à la rotation autour du centre de rotation instantané (ICR), ces robots peuvent effectuer des trajectoires planaires complexes de $ 2D $. Ils sont moins chers et ont une capacité de charge plus élevée que les roues non conventionnelles (par exemple, Sweedish ou Omni-directional) et, en tant que telles, préférées aux applications industrielles. Cependant, ce type de structure de robot mobile présente des problèmes de contrôle textit {basic} difficiles de la coordination de la direction pour éviter les combats d'actionneur, en évitant les singularités cinématiques (ICR à l'axe de la direction) et les singularités de représentation (du modèle mathématique). En plus de résoudre les problèmes de contrôle textit {basic}, cette thèse attire également l'attention et présente des solutions aux problèmes de textit {niveau d'application}. Plus précisément, nous traitons deux problèmes: la première est la nécessité de reconfigurer "de manière discontinue" les articulations de direction, une fois que la discontinuité dans la trajectoire du robot se produit. Une telle situation - la discontinuité dans le mouvement du robot - est plus susceptible de se produire de nos jours, dans le domaine émergent de la collaboration homme-robot. Les robots mobiles qui fonctionnent à proximité des travailleurs humains en mouvement rapide rencontrent généralement une discontinuité dans la trajectoire calculée en ligne. Le second apparaît dans les applications nécessitant que l'angle de l'angle soit maintenu, certains objets ou fonctionnalités restent dans le champ de vision (p. Ex., Pour les tâches basées sur la vision) ou les changements de traduction. Ensuite, le point ICR est nécessaire pour déplacer de longues distances d'un extrême de l'espace de travail à l'autre, généralement en passant par le centre géométrique du robot, où la vitesse du robot est limitée. Dans ces scénarios d'application, les contrôleurs basés sur l'ICR à l'état de l'art conduiront à des comportements / résultats insatisfaisants. Dans cette thèse, nous résolvons les problèmes de niveau d'application susmentionnés; à savoir la discontinuité dans les commandes de vitesse du robot et une planification meilleure / efficace pour le contrôle du mouvement du point ICR tout en respectant les limites maximales de performance des articulations de direction et en évitant les singularités cinématiques et représentatives. Nos résultats ont été validés expérimentalement sur une base mobile industrielleSteerable wheeled mobile robots gain mobility by employing fully steerable conventional wheels, having two active joints, one for steering, and another for driving. Despite having only one degree of mobility (DOM) (defined here as the instantaneously accessible degrees of freedom DOF), corresponding to the rotation about the instantaneous center of rotation (ICR), such robots can perform complex $2D$ planar trajectories. They are cheaper and have higher load carrying capacity than non-conventional wheels (e.g., Sweedish or Omni-directional), and as such preferred for industrial applications. However, this type of mobile robot structure presents challenging textit{basic} control issues of steering coordination to avoid actuator fighting, avoiding kinematic (ICR at the steering joint axis) and representation (from the mathematical model) singularities. In addition to solving the textit{basic} control problems, this thesis also focuses attention and presents solutions to textit{application level} problems. Specifically we deal with two problems: the first is the necessity to "discontinuously" reconfigure the steer joints, once discontinuity in the robot trajectory occurs. Such situation - discontinuity in robot motion - is more likely to happen nowadays, in the emerging field of human-robot collaboration. Mobile robots working in the vicinity of fast moving human workers, will usually encounter discontinuity in the online computed trajectory. The second appears in applications requiring that some heading angle is to be maintained, some object or feature stays in the field of view (e.g., for vision-based tasks), or the translation verse changes. Then, the ICR point is required to move long distances from one extreme of the workspace to the other, usually passing by the robot geometric center, where the feasible robot velocity is limited. In these application scenarios, the state-of-art ICR based controllers will lead to unsatisfactory behavior/results. In this thesis, we solve the aforementioned application level problems; namely discontinuity in robot velocity commands, and better/efficient planning for ICR point motion control while respecting the maximum steer joint performance limits, and avoiding kinematic and representational singularities. Our findings has been validated experimentally on an industrial mobile base
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Li, Wan-chiu. "Localization of a mobile robot by monocular vision /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23765896.
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Gonullu, Muhammet Kasim. "Development Of A Mobile Robot Platform To Be Used In Mobile Robot Research." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615654/index.pdf.
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Robotics is an interdisciplinary subject and combines mechanical, computer and electrical engineering components together to solve different kinds of problems. In order to build robotic systems, these disciplines should be integrated. Therefore, mobile robots can be used as a tool in education for teaching engineering concepts. They can be employed to be used in undergraduate, graduate and doctorate research. Hands on experience on a mobile robot increase motivation of the students on the topic and give them precious practical knowledge. It also delivers students new skills like teamwork, problem solving, creativity, by executing robotic exercises. To be able to fulfill these outcomes, universities and research centers need mobile robot platforms that are modular, easy to build, cheap and flexible. However it should be also powerful and capable of being used in different research studies and hence be customizable depending on the requirements of these topics.
This thesis aims at building an indoor mobile robot that can be used as a platform for developing algorithms involving various sensors incorporated onto a mobile platform. More precisely, it can be used as a base for indoor navigation and localization algorithms, as well as it can be used as platform for developing algorithms for larger autonomous mobile robots. The thesis work involves the design and manufacturing of a mobile robot platform that can potentially facilitate mobile robotics research that involves use of various hardware to develop and test different perception and navigation algorithms.
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Tennety, Srinivas. "Mobile robot navigation in hilly terrains." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1313757135.
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李宏釗 and Wan-chiu Li. "Localization of a mobile robot by monocular vision." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31226371.
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Olafsson, Asgrimur. "Autonomous Mobile Robot Cooperation." Thesis, University of Skövde, Department of Computer Science, 1997. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-242.
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This project is concerned with an investigation of simple communication between ANN-controlled mobile robots. Two robots are trained on a (seemingly) simple navigation task: to stay close to each other while avoiding collisions with each other and other obstacles.
A simple communication scheme is used: each of the robots receives some of the other robots’ outputs as inputs for an algorithm which produces extra inputs for the ANNs controlling the robots.
In the experiments documented here the desired cooperation was achieved. The different problems are analysed with experiments, and it is concluded that it is not easy to gain cooperation between autonomous mobile robots by using only output from one robot as input for the other in ANNs.
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HASSANZADEH, Aidin. "Mobile Robot Wind Mapping." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-34606.
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Statistical gas distribution mapping has recently become a prominent research area in the robotics community. Gas distribution mapping using mobile robots aims for building map of gas dispersion in an unknown environment using the sampled gas concentrations accompanied by the corresponding atmospheric variables. In this context, wind is considered as one of the main driving forces and recently exploited as an environmental bias in the the modelling process. However, the existing approaches utilizing the wind data are based on very simple averaging window methods which do not take the specic spatio-temporal wind variations into account appropriately. In the current thesis work, under the heading of statistical wind modelling, the various aspects of the existing approaches to model both temporal and spatial wind variations are studied. Accordingly, in the undertaking of Mobile Robot Wind Mapping (MRWM) task, three individual methods for statistically wind speed modelling, wind direction modelling and spatial wind mapping are proposed and implemented. Particularly, wind speed is modelled in form of a Gaussian distribution where the valid averaging scale is dened using an online adaptive approach, namely Time-Dependent Memory Method (TDMM) . The wind direction is modelled by means of the mixturemodel of Von-Mises distribution and for the spatial mapping of modelled wind data, a recursive approach based on Linear Kalman lter is utilized. The proposed approaches for statistically wind speed and direction modelling are applied to and evaluated by real wind data, collected specically for this project. The wind mapping algorithm is implemented and tested using simulated data.
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Celikkanat, Hande. "Control Of A Mobile Robot Swarm Via Informed Robots." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609966/index.pdf.
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In this thesis, we study how and to what extent a self-organized mobile robot flock can be guided by informing some of the robots within the flock about a preferred direction of motion. Specifically, we extend a flocking behavior that was shown to maneuver a swarm of mobile robots as a cohesive group in free space, avoiding obstacles. In its original form, this behavior does not have a preferred direction and the flock would wander aimlessly. In this study, we incorporate a preference for a goal direction in some of the robots. These informed robots do not signal that they are informed (a.k.a. unacknowledged leadership) and instead guide the swarm by their tendency to move in the desired direction. Through experimental results with physical and simulated robots we show that the self-organized flocking of a robot swarm can be effectively guided by an informed minority of the flock. We evaluate the system using a number of quantitative metrics: First, we propose to use the mutual information metric from Information Theory as a dynamical measure of the information exchange. Then, we discuss the accuracy metric from directional statistics and size of the largest cluster as the measures of system performance. Using these metrics, we perform analyses from two points of views: In the transient analyses, we demonstrate the information exchange between the robots as the time advances, and the increase in the accuracy of the flock when the conditions are suitable for an adequate amount of information exchange. In the steady state analyses, we investigate the interdependent effects of the size of the flock in terms of the robots in it, the ratio of informed robots in the flock over the total flock size, the weight of the direction preference behavior, and the noise in the system.
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Wooden, David T. "Graph-based Path Planning for Mobile Robots." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-11092006-180958/.
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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2007.Magnus Egerstedt, Committee Chair ; Patricio Vela, Committee Member ; Ayanna Howard, Committee Member ; Tucker Balch, Committee Member ; Wayne Book, Committee Member.
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Chen, Haoyao. "Towards multi-robot formations : study on vision-based localization system /." access full-text access abstract and table of contents, 2009. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?phd-meem-b3008295xf.pdf.
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Thesis (Ph.D.)--City University of Hong Kong, 2009."Submitted to Department of Manufacturing Engineering and Engineering Management in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves 87-100)
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Smith, Brian Stephen. "Automatic coordination and deployment of multi-robot systems." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28248.
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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.Committee Chair: Dr. Magnus Egerstedt; Committee Co-Chair: Dr. Ayanna Howard; Committee Member: Dr. David Taylor; Committee Member: Dr. Frank Dellaert; Committee Member: Dr. Ian Akyildiz; Committee Member: Dr. Jeff Shamma.
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Kwok, Chung Tin. "Robust real-time perception for mobile robots /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/7017.
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Litter, Jansen J. "Mobile robot for search and rescue." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1176921842.
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Sequeira, Gerard. "Vision based leader-follower formation control for mobile robots." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Sequeira_09007dcc804429d4.pdf.
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Thesis (M.S.)--University of Missouri--Rolla, 2007.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 13, 2008) Includes bibliographical references (p. 39-41).
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Switzer, Barbara T. "Robotic path planning with obstacle avoidance /." Online version of thesis, 1993. http://hdl.handle.net/1850/11712.
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Pradalier, Cédric. "Navigation intentionnelle d'un robot mobile." Phd thesis, Grenoble INPG, 2004. http://tel.archives-ouvertes.fr/tel-00147375.
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Inscrit dans le contexte de la robotique autonome, cette thèse se focalise sur l'étude de la navigation intentionnelle, c'est à dire le pilotage d'un robot mobile de façon à atteindre un but
en tenant compte d'informations perceptives.
Pour atteindre cet objectif, nous allons nous poser trois questions fondamentales que nous
préciserons par la suite :
– Comment définir une tâche de navigation intentionnelle (TNI) ?
– Comment réaliser une TNI ?
– Comment implanter une TNI ?
Nos réponses à ces questions s'articulent en une arborescence de problématiques que nous
illustrons dans la figure 1.1. Nous allons maintenant détailler cette arborescence.
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Skumsnes, Bjørn Heber. "Teleoperation of Mobile Robot Manipulators." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18438.
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With ever cheaper and more versatile robots, the use of robotic systems in creases rapidly. Although robots are becoming more intelligent, the cognitive capabilities of humans can still not be matched. By combining the intelligence of a human operator with the strength, endurance and size of a robot, in addition to separating the robot and operator to avoid danger to the operator, the applications are innumerable. The use of an operator to remotely control a robot is often referred to as teleoperation.In a teleoperation system it is important to present the state of the robot and the remote environment with high accuracy and in a comprehensible way. With a large number of sensor data, a solution is to enhance the feeling of telepresence or transparency of the system. That is, making the human operator feel like he or she is interacting directly with the manipulated environment. This could be achieved by using a haptic joystick, which is able to generate force feedback to the operator, to present information about the slave robot. Examples of such informations are the distance to an obstacle or deviation from a desired movement. Such a system is often called a bilateral teleoperation system, where the stability is especially sensitive to transmission delay. This time-delay is often introduced by the communication network between the human operator and remote robot.This thesis presents a control architecture for interpreting a change in the joystick position to a desired end-effector velocity for a mobile manipulator. In addition to calculating the velocity, the controller is designed to comply with the joint limits, optimize the manipulability and handle time-varying transmission delay. A force, that depends on the deviation between the desired and measured end-effector position, is sent back to the human operator, as well as a visual feedback. To increase the precision of the end-effector movement the position of the movable robot base is fixed when the manipulability is above a given threshold, and moves only to increase the workspace of the robot. The designed system is implemented using Robot Operating System (ROS) and tested on a virtual mobile manipulator. The virtual robot is based on a model of a Schunk LWA3 7-DOF manipulator, mounted on a Seekur Jr. wheeled mobile base.Several experiments prove that the system with the proposed control architecture is stable when under influence of constant, as well as variable time-delay. Any standard deviation between the measured and desired end-effector position is eliminated, and the trajectory of the end-effector is almost identical the desired, though delayed when affected by communication delay. Neither the force feedback nor end-effector position show indications of dramatic change at the transition between fixed and moving robot base. Simulations with human operators show that they are able to move the end-effector of a virtual mobile manipulator from an initial position to a predefined goal, with the use of a Phantom Omni, haptic joystick.
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Jos´e, Iglesias Garc´ıa Fernando. "Cloud-based Mobile Robot Localization." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-153649.
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Molnbaserad mobil robotlokalisering Cloud robotics Är en modern inställning till robotik baserad på datormoln, lagringsmoln och andra internettjänster som robotar kan använda för att överkomma fundamentala begränsningar i inbygd beräkning och lagringsskalbarhet. Det här nya delområdet inom robotik drivs av den snabba utvecklingen av trådlös kommunikation och lättillgänglig molnbaserad infrastruktur som tillhandahålls av stora företag som till exempel Google, Amazon och Microsoft. Målet med det här projektet är att designa och implementera en molnbaserad prototyp för mobil robotlokalisering inomhus med RGB-D kameror. Lokalisering är ett fundamentalt problem inom robotik och har undersökts i den här rapporten. Rapporten behandlar även särdragsextraktion av 3D-bilder för robotlokalisering. Som ett resultat av det här projektet presenteras ett nytt system av molnbaserad robotlokalisering. Systemet använder öppen programvara som ROS och GraphLab. Slutligen, experiment redovisar fördelar och nackdelar med vårt tillvägagångssätt.Cloud robotics is a modern approach to robotics based on cloud computing, cloud storage and other Internet services that robots can benefit from to overcome fundamental limitations in on-board computation and memory scalability. This new subfield of robotics is driven by the rapid progress of wireless communications and easy-toaccess cloud infrastructure provided by large industries such as Google, Amazon, and Microsoft. The goal of this project consists of the design and implementation of a prototype for indoor mobile robot localization with RGB-D cameras leveraging the cloud. Localization is a fundamental problem in autonomous robotics surveyed in this report. In addition, extraction of features for localization from depth images is also addressed. As a result of this project, a new system for cloud-based robot localization is presented. The system makes use of modern opensource software such as ROS and GraphLab. Finally, experiments are presented to analyse the improvements and limitations achieved by our approach.
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Sprunk, Christoph [Verfasser], and Wolfram [Akademischer Betreuer] Burgard. "Highly accurate mobile robot navigation." Freiburg : Universität, 2015. http://d-nb.info/1119452481/34.
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Kuderer, Markus [Verfasser], and Wolfram [Akademischer Betreuer] Burgard. "Socially compliant mobile robot navigation." Freiburg : Universität, 2015. http://d-nb.info/1114669814/34.
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Sherfey, Solomon Rand. "A mobile robot sonar system." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/26635.
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Long, Xianchao. "Tactile-Based Mobile Robot Navigation." Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-theses/891.
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"This thesis presents an effective approach to study tactile based mobile robot navigation. A Matlab simulator, which can simulate the properties of the tactile sensors, the environment, and the motion of the robot, is developed. The simulator uses an abstraction model of a compliant tactile sensor to represent an array of sensors covering the robot. The tactile sensor can detect normal and shear forces. The simulator has been used by a set of human subjects to drive a robot in an indoor environment to capture data. The details of the implementation and the data collected are presented in this thesis. From the data, some contact features can be extracted. Regarding the features, this thesis uses the Gaussian classifier and Gaussian mixture model to classify the data and build the feature classification model. Comparing the classification results of these two methods, the Gaussian mixture model has better performance. Applying the feature classification model, some contact objects can be detected, such as wall and corner. Based on this classification tool, a simple navigation problem can be solved successfully."
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Devillard, François. "Vision du robot mobile Mithra." Grenoble INPG, 1993. http://www.theses.fr/1993INPG0112.
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Nous proposons un ensemble de vision stereoscopique embarque, destine a la navigation d'un robot mobile en site industriel. En robotique mobile, les systemes de vision sont soumis a de severes contraintes de fonctionnement (traitement en temps reel, volume, consommation. . . ). Pour une modelisation 3D de l'environnement, le systeme de vision doit utiliser des indices visuels permettant un codage compact, precis et robuste de la scene observee. Afin de repondre au mieux aux contraintes de vitesse, nous nous sommes attaches a extraire, des images, les informations les plus significatives d'un point de vue topologique. Dans le cas de missions en sites industriels, l'ensemble des projets presente des geometries orthogonales telles que les intersections de cloisons, les portes, les fenetres, le mobilier. . . La detection des geometries proches de la verticale permet une definition suffisante de l'environnement tout en reduisant la redondance des informations visuelles dans des proportions satisfaisantes. Les indices utilises sont des segments de droite verticaux extraits de deux images stereoscopiques. Nous proposons des solutions algorithmiques pour la detection de contours et l'approximation polygonale adaptees a une implementation temps reel. Ensuite, nous presentons le systeme de vision realise. L'ensemble est constitue de 2 cartes VME. La premiere carte est un operateur cable systolique implementant l'acquisition d'images et la detection de contours. La seconde est concue a partir d'un processeur de traitement de signal et realise l'approximation polygonale. La conception et la realisation de ce systeme de vision a ete realisee dans le cadre du projet de robotique mobile EUREKA EU 110 (Mithra)
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Muhammad, Naveed. "Contributions to the use of 3D lidars for autonomous navigation : calibration and qualitative localization." Thesis, Toulouse, INSA, 2012. http://www.theses.fr/2012ISAT0001/document.
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Afin de permettre une navigation autonome d'un robot dans un environnement, le robot doit être capable de percevoir son environnement. Dans la littérature, d'une manière générale, les robots perçoivent leur environnement en utilisant des capteurs de type sonars, cameras et lidar 2D. L'introduction de nouveaux capteurs, nommés lidar 3D, tels que le Velodyne HDL-64E S2, a permis aux robots d'acquérir plus rapidement des données 3D à partir de leur environnement. La première partie de cette thèse présente une technique pour la calibrage des capteurs lidar 3D. La technique est basée sur la comparaison des données lidar à un modèle de vérité de terrain afin d'estimer les valeurs optimales des paramètres de calibrage. La deuxième partie de la thèse présente une technique pour la localisation et la détection de fermeture de boucles pour les robots autonomes. La technique est basée sur l'extraction et l'indexation des signatures de petite-taille à partir de données lidar 3D. Les signatures sont basées sur les histogrammes de l'information de normales de surfaces locale extraite à partir des données lidar en exploitant la disposition des faisceaux laser dans le dispositif lidarIn order to autonomously navigate in an environment, a robot has to perceive its environment correctly. Rich perception information from the environment enables the robot to perform tasks like avoiding obstacles, building terrain maps, and localizing itself. Classically, outdoor robots have perceived their environment using vision or 2D lidar sensors. The introduction of novel 3D lidar sensors such as the Velodyne device has enabled the robots to rapidly acquire rich 3D data about their surroundings. These novel sensors call for the development of techniques that efficiently exploit their capabilities for autonomous navigation.The first part of this thesis presents a technique for the calibration of 3D lidar devices. The calibration technique is based on the comparison of acquired 3D lidar data to a ground truth model in order to estimate the optimal values of the calibration parameters. The second part of the thesis presents a technique for qualitative localization and loop closure detection for autonomous mobile robots, by extracting and indexing small-sized signatures from 3D lidar data. The signatures are based on histograms of local surface normal information that is efficiently extracted from the lidar data. Experimental results illustrate the developments throughout the manuscript
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Da, Silva Filho José Grimaldo. "Towards natural human-robot collaboration during collision avoidance." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALM003.
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Ces dernières années, la tendance des robots capables de partager des espaces domestiques ou de travail avec des personnes a connu une croissance importante. Du robot guide à l’aspirateur autonome, ces robots dits "de service" sont de plus en plus intégrés dans la vie quotidienne des profanes.Bien que les progrès des logiciels et du matériel aient permis un comportement plus intelligent et plus autonome des robots, la présence plus répandue des robots parmi les gens pose un nouvel ensemble de défis pour la communauté scientifique. Même si les gens ne sont pas que des obstacles ordinaires, les approches classiques de navigation se sont concentrées sur la garantie d’un mouvement sans collision en supposant que les gens sont soit des obstacles statiques, soit des obstacles en mouvement. Traiter les gens comme des obstacles ordinaires signifie qu’un robot est incapable de tenir compte de la réaction d’une personne au mouvement du robot. Pour cette raison, un mouvement donné d’un robot peut être perçu comme dangereux ou inhabituel, ce qui incite les gens à adopter un mouvement plus prudent pendant qu’ils réfléchissent activement aux intentions du robot. Dans ce contexte, notre travail se concentre sur la manière dont un robot doit se déplacer au milieu des gens, ce qu’on appelle un problème de Mouvement homme-robot. Plus précisément, nous nous concentrons sur la reproduction d’une caractéristique de l’interaction homme-homme lors de la prévention des collisions, à savoir le partage mutuel des adaptations effectuées pour résoudre une collision.Etant donné que les situations d’évitement des collisions entre les personnes sont résolues en coopération, cette thèse modélise la manière dont cette coopération se fait afin qu’un robot puisse reproduire leur comportement. Pour ce faire, des centaines de situations où deux personnes ont des trajectoires de croisement ont été analysées. À partir de ces trajectoires humaines impliquant une tâche d’évitement des collisions, nous avons déterminé comment l’effort total est partagé entre chaque agent en fonction de plusieurs facteurs de l’interaction tels que l’angle de croisement, le temps avant collision ainsi que la vitesse. Pour valider notre approche, une preuve de concept est intégrée dans le framework Robot Operating System (ROS) utilisant une version modifiée de Reciprocal Velocity Objects (RVO) afin de répartir l’effort d’évitement des collisions de façon humanoïde.Bien que la modélisation de la manière dont un robot devrait collaborer avec des personnes ait fourni une base de référence importante pour le comportement d’évitement des collisions, la collaboration pendant une collision pourrait éventuellement engendrer de conséquences négatives. En particulier, pour assurer une collaboration efficace lors de la prévention des collisions, il est nécessaire de prévoir si la personne tentera d’éviter la collision en passant du côté gauche ou du côté droit, c’est-à-dire en prenant une décision de classe homotopie. Cependant, à situation ou cette décision de classe d’homotopie n’est pas cohérente pour les gens, le robot est obligé de tenir compte de la possibilité que les deux agents tentent de se croiser d’un côté ou de l’autre et prennent une décision nuisible à la prévention des collisions.Ainsi, dans cette thèse, nous évaluons également ce qui détermine la frontière qui sépare la décision d’éviter la collision d’un côté ou de l’autre. En faisant une approximation de l’incertitude entourant cette limite, nous avons élaboré une stratégie d’évitement des collisions qui tente de résoudre ce problème. Notre approche est basée sur l’idée que le robot doit planifier son mouvement d’évitement des collisions de telle sorte que, même si les agents, dans un premier temps, choisissent à tort de se croiser sur des côtés différents, le robot et la personne soient capables de percevoirClassical approaches for robot navigation among people have focused on guaranteed collision-free motion with the assumption that people are either static or moving obstacles. However, people are not ordinary obstacles. People react to the presence and the motion of a robot. In this context, a robot that behaves in human-like manner has been shown to reduce overall cognitive effort for nearby people as they do not have to actively think about a robot's intentions while moving on its proximity.Our work is focused on replicating a characteristic of human-human interaction during collision avoidance that is the mutual sharing of effort to avoid a collision. Based on hundreds of situations where two people have crossing trajectories, we determined how total effort is shared between agents depending on several factors of the interaction such as crossing angle and time to collision. As a proof of concept our generated model is integrated into gls{rvo}. For validation, the trajectories generated by our approach are compared to the standard gls{rvo} and to our dataset of people with crossing trajectories.Collaboration during collision avoidance is not without its potential negative consequences. For effective collaboration both agents have to pass each other on the same side. However, whenever the decision of which side collision should be avoided from is not consistent for people, the robot should also account for the risk that both agents will attempt to incorrectly cross each other on different sides. Our work first determines the uncertainty around this decision for people. Based on this, a collision avoidance approach is proposed so that, even if agents initially choose to incorrectly attempt to cross each other on different sides, the robot and the person would be able to perceive the side from which collision should be avoided in their following collision avoidance action. To validate our approach, several distinct scenarios where the crossing side decision is ambiguous are presented alongside collision avoidance trajectories generated by our approach in such scenarios
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Kulkarni, Suyash M. "Mobile Robot Localization with Active Landmark Deployment." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535702460399878.
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Gregoire, Jean. "Priority-based coordination of mobile robots." Thesis, Paris, ENMP, 2014. http://www.theses.fr/2014ENMP0023/document.
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Depuis la fin des années 1980, le développement de véhicules autonomes, capables de rouler sans l'intervention d'un être humain, est un champ de recherche très actif dans la plupart des grands pays industrialisés. La diminution du nombre d'accidents, des temps de trajet plus courts, une meilleure efficacité énergétique et des besoins en infrastructure plus limités, sont autant d'effets socio-économiques espérés de leur déploiement. Des formes de coopération inter-véhicules et entre les véhicules et l'infrastructure routière sont nécessaires au fonctionnement sûr et efficace du système de transport dans sa globalité. Cette thèse s'intéresse à une forme de coopération particulière en étudiant la coordination de robots mobiles aux intersections. La majorité des systèmes de coordination existants planifie une trajectoire que les robots doivent exécuter afin d'assurer l'absence de collision. C'est une approche classique de la planification, qui est alors considérée comme un mécanisme de génération de l'action. Dans cette thèse, seules les priorités entre les véhicules sont planifiées, c'est-à-dire l'ordre relatif de passage des véhicules dans l'intersection, ce qui est bien plus faible car un grand nombre de trajectoires respectent les même priorités. Les priorités sont alors simplement utilisées comme une ressource de coordination pour guider les robots dans l'intersection. Une fois les priorités affectées, les robots suivent une loi de contrôle qui s'assure qu'elles soient bien respectées. Il en découle un système de coordination robuste, capable de gérer toute une classe d'événements imprévisibles de façon réactive, ce qui est particulièrement adapté pour une application à la coordination de véhicules autonomes aux intersections où voitures, transports en commun et piétons partagent la routeSince the end of the 1980's, the development of self-driven autonomous vehicles is an intensive research area in most major industrial countries. Positive socio-economic potential impacts include a decrease of crashes, a reduction of travel times, energy efficiency improvements, and a reduced need of costly physical infrastructure. Some form of vehicle-to-vehicle and/or vehicle-to-infrastructure cooperation is required to ensure a safe and efficient global transportation system. This thesis deals with a particular form of cooperation by studying the problem of coordinating multiple mobile robots at an intersection area. Most of coordination systems proposed in previous work consist of planning a trajectory and to control the robots along the planned trajectory: that is the plan-as-program paradigm where planning is considered as a generative mechanism of action. The approach of the thesis is to plan priorities – the relative order of robots to go through the intersection – which is much weaker as many trajectories respect the same priorities. Then, priorities are merely used as a coordination resource to guide robots through the intersection. Once priorities are assigned, robots are controlled through a control law preserving the assigned priorities. It results in a more robust coordination system – able to handle a large class of unexpected events in a reactive manner – particularly well adapted for an application to the coordination of autonomous vehicles at intersections where cars, public transport and pedestrians share the road
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Habert, Olivier. "Modélisation dynamique d'un environnement intérieur pour robot mobile." Nancy 1, 1995. http://www.theses.fr/1995NAN10051.
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Les travaux présentés dans ce mémoire concernent les aspects modélisation de l'environnement et planification de trajectoire du projet V. A. H. M. (véhicule autonome pour handicapé moteur). Nous proposons d'exploiter les informations provenant d'une représentation incertaine de l'environnement. L’originalité de cette représentation provient du fait qu'elle est issue d'un dessin a vue effectue par un opérateur humain. Nous résolvons le problème de l'interprétation et de l'évaluation des incertitudes par une modélisation simple du comportement humain qui consiste à utiliser des relations de proximité entre les primitives géométriques du dessin originel. À partir de la modélisation par nombres multivaleurs de l'environnement à priori, nous effectuons des planifications de trajectoires. L’utilisation des caractéristiques incertaines du modèle permet alors la mise en évidence des régions ou la navigation du robot présente de hauts risques de collision avec les obstacles. Le fauteuil est équipé de capteurs extéroceptifs (capteurs à ultrasons) et proprioceptifs (odomètre) qui autorisent respectivement l'observation de l'environnement et l'estimation de la localisation. Lors de la navigation du robot dans l'environnement, la mise en correspondance du modèle et des données issues des moyens de perception permet d'effectuer une modification de la configuration des objets modélisés. Après plusieurs déplacements dans le milieu d'évolution, on observe une convergence de la configuration relative des objets vers leur configuration réelle
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Winter, Pieter Arnoldus. "Position control of a mobile robot /." Link to the online version, 2005. http://hdl.handle.net/10019/1317.
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Bennewitz, Maren. "Mobile robot navigation in dynamic environments." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971778329.
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McNamee, Louis P. "Photogrammetric calibration of mobile robot kinematics." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26522.
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Numerous simulation and control applications of mobile robotics require accurate kinematic models. A kinematic model relates the position and orientation of a robot to control inputs. This thesis proposes a non-intrusive methodology to calibrate kinematic models for wheeled mobile robots. Model calibration requires accurate measurement of kinematic state and robust estimation techniques to account for process and measurement uncertainty. A photogrammetric camera system is used to measure the kinematic trajectory of wheeled mobile robot. A fully projective formulation of Lowe's pose recovery algorithm is used to estimate robot pose from monocular images. A derivative free form of the extended Kalman filter is applied to the time series pose data to estimate robot model parameters. Experimental results are presented for a differential wheeled mobile robot. Calibration by photogrammetry is shown to be viable for typical mobile robot applications.
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Sim, Robert. "Mobile robot localisation using learned landmarks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0007/MQ44278.pdf.
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Flynn, Anita M. "Redundant Sensors for Mobile Robot Navigation." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/6871.
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Redundant sensors are needed on a mobile robot so that the accuracy with which it perceives its surroundings can be increased. Sonar and infrared sensors are used here in tandem, each compensating for deficiencies in the other. The robot combines the data from both sensors to build a representation which is more accurate than if either sensor were used alone. Another representation, the curvature primal sketch, is extracted from this perceived workspace and is used as the input to two path planning programs: one based on configuration space and one based on a generalized cone formulation of free space.
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Lonji, Kadima. "Mobile robot teleoperation using enhanced video." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=24021.
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In the context of teleoperated mobile robotics, the use of video data is one of the most desirable sensing modalities for vehicle guidance. Unfortunately, maintaining reliable noise-free video transmission, especially in cost sensitive teleoperation applications is a frequent problem.We developed a mobile robot system for teleoperation using a robot mounted camera as a primary sensor. This system functions in a partially-known environment for which a 3D geometric map is available. In this thesis we describe aspects of the system related to enhanced reality, that is the augmentation of the returned video data with information extracted from the world knowledge base. If during robot navigation our sensor data (returned video) experiences transmission delays or becomes too noisy or obstructed, we superimposed artificially generated graphics (using the model representation) onto a regular video picture. Once a clear transmission was recaptured or the obscuring obstacle shifted from its old position, video data covering that area of the image was redisplayed for consequent navigation. This task of fusing these two representations together simultaneously, in an efficient and realistic fashion during robot teleoperation, was the goal of our research.
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Davison, Andrew John. "Mobile robot navigation using active vision." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298606.
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Burke, Thomas P. H. "Design of a modular mobile robot." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339301.
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Olumuyiwa, Ibikunle Ashiru. "Evolutionary approaches to mobile robot systems." Thesis, De Montfort University, 1997. http://hdl.handle.net/2086/10667.
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Kehoe, Charles W. (Charles Ward). "Indexical grounding for a mobile robot." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33304.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (p. 26-27).
We have outfitted a mobile research robot with several sensors and algorithms designed to facilitate small- and large-scale navigation and natural language interaction. We begin with a parser using a large, hand-crafted English grammar and lexicon. We then add a standard gradient navigation algorithm for local obstacle avoidance, and a line segment comparison algorithm for basic, high-performance location recognition. The result is a full end-to-end system for natural-language-driven, mobile robotics research. The theme of grounding-mapping linguistic references to the corresponding real-world entities-runs throughout our approach. After the parser simplifies linguistic symbols and structures, we must connect them to the basic concepts that they represent, and then to our system's specific sensor readings and motor commands, to make natural language interaction possible. Additionally, many of the symbols we must ground are indexicals with critical contextual dependencies. We must therefore handle the implicit context that spatial communication carries with it.
by Charles W. Kehoe.
M.Eng.
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Winter, Pieter. "Position control of a mobile robot." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/1776.
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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2005.Position calculation of mobile objects has challenged engineers and designers for years and is still continuing to do so. There are many solutions available today. Probably the best known and most widely used outdoor system today is the Global Positioning System (GPS). There are very little systems available for indoor use. An absolute positioning system was developed for this thesis. It uses a combination of ultrasonic and Radio Frequency (RF) communications to calculate a position fix in doors. Radar techniques were used to ensure robustness and reliability even in noisy environments. A small mobile robot was designed and built to test and illustrate the use of the system.
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Bedwani, Jean-Luc. "Atlas multi-couches pour robot mobile." Mémoire, Université de Sherbrooke, 2009. http://savoirs.usherbrooke.ca/handle/11143/1508.
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En cherchant à connaitre les origines de la vie sur Terre, on se demande également si elle peut se trouver ailleurs. Malgré le fait que Mars nous est voisine et qu'elle ne semble pas en démontrer la présence, on désire toutefois l'étudier et la comparer avec la Terre. Pour y arriver, l'Homme a recours à la technologie : les télescopes, satellites, sondes et robots servent à observer Mars. À chacune des expéditions d'observation de Mars, nous cherchons à en connaître davantage et améliorons en conséquence la technologie utilisée. C'est pour cela que la prochaine génération de véhicules d'exploration planétaire nécessitera une plus grande autonomie de navigation. De tels requis impliquent une gestion adéquate de données géoréférencées potentiellement volumineuses et denses, représentées sous la forme de cartes. Ce mémoire présente l'état des recherches faites sur un système de gestion de données utilisable dans un contexte d'exploration planétaire autonome. Pour valider un tel système, il a fallu utiliser, mais ,également constituer, un répertoire de cartes en trois dimensions ayant été géoréférencées. Afin d'obtenir un répertoire représentatif du contexte d'utilisation, il a également été nécessaire de développer un comportement d'exploration et de navigation sur une plateforme robotisée, capable d'acquérir les cartes requises. À l'aide de ce répertoire, il a été possible de vérifier les capacités, les performances ainsi que l'exactitude des opérations effectuées à l'aide du système de gestion proposé. Un article intégré au mémoire présente la conception d'un tel système de gestion de données, ainsi qu'une solution permettant de gérer dynamiquement une variété de données, l'incertitude des relations spatiales entre deux cartes, de procurer un mécanisme de planification de chemins au travers des cartes, ainsi que la corrélation des cartes pour les opérations de localisation. Cet article présente également les résultats expérimentaux sur l'utilisation du système de gestion atlas par un véhicule d'exploration autonome. En plus de démontrer la faisabilité et l'utilité d'un tel gestionnaire de données en navigation autonome, le système pourrait également être utilisé comme plateforme d'analyse afin de comparer les performances de différents algorithmes de recalage de surfaces.
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Grondin, François. "Reconnaissance de locuteurs pour robot mobile." Mémoire, Université de Sherbrooke, 2012. http://savoirs.usherbrooke.ca/handle/11143/1632.
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L'audition artificielle est de plus en plus utilisée en robotique mobile pour améliorer l'interaction humain-robot. La reconnaissance de la parole occupe présentement une place importante tandis qu'un intérêt particulier se développe pour la reconnaissance de locuteurs. Le système ManyEars permet actuellement à un robot mobile de localiser, suivre et séparer plusieurs sources sonores. Ce système utilise un ensemble de huit microphones qui sont disposés en cube. Ce mémoire porte sur la conception et l'évaluation d'un système de reconnaissance de locuteurs, baptisé WISS (Who IS Speaking), couplé au système ManyEars. Le système de reconnaissance de locuteurs conçu est robuste au bruit ambiant et au changement d'environnement. Une technique de combinaison de modèle parallèle (parallel model combination (PMC)) et des masques sont utilisés pour améliorer le taux d'identification dans un milieu bruité. Un indice de confiance est également introduit pour pondérer les identifications obtenues. La simplicité du système proposé fait en sorte qu'il est possible d'exécuter en temps réel l'algorithme sur un processeur généraliste ( General Purpose Processor (GPP)). Les performances du système sont établies à l'aide de plusieurs scénarios. Dans un premier lieu, des enregistrements sont diffusés dans des haut-parleurs pour un ensemble de vingt locuteurs. Le système est ainsi caractérisé en fonction des positions angulaires et radiales des sources sonores. Le taux de reconnaissance est affecté par la qualité du signal (i.e. diminution du rapport signal sur bruit ( Signal-to-Noise Ratio (SNR))) : il passe de 95.6% à 84.3% en moyenne lorsque le SNR passe d'environ 16 dB à 2 dB lorsque le locuteur se situe à 1.5 mètres des microphones. Par la suite, un scénario dit statique est vérifié à l'aide de quatre locuteurs qui récitent chacun leur tour des phrases à un volume de voix naturel. Finalement, un scénario dynamique dans lequel un groupe de quatre locuteurs ont une conversation naturelle avec des chevauchements entre les segments de paroles est étudié. Le taux de reconnaissance varie entre 74.2% et 100.0% (avec une moyenne de 90.6%) avec le scénario statique, et entre 42.6% et 100.0% avec le scénario dynamique (avec des moyennes de 58.3%, 72.8% et 81.4% pour des segments de 1, 2 et 3 secondes respectivement). Des solutions sont identifiées afin d'améliorer les performances lors de travaux futurs. Au meilleur de notre connaissance, il n'existe aucun système qui effectue une reconnaissance de locuteurs dans un environnement contaminé simultanément par des bruits convolutif et additif. De plus, l'utilisation de masques pour estimer ces bruits est un nouveau concept. Ces masques sont d'ailleurs généralement employés pour la reconnaissance de la parole et leur utilisation dans un contexte de reconnaissance de locuteur est une première. De plus, une caractérisation complète du système qui inclue les SNRs est proposée en fonction de la position du locuteur, ce qui est rarement disponible dans la littérature en audition artificielle pour les robots.
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Le, Bras-Mehlman Elizabeth. "Représentation de l'environnement d'un robot mobile." Paris 11, 1989. http://www.theses.fr/1989PA112195.
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Le robot mobile de l'INRIA est doté d'un système de vision qui fournit des segments 3D, situés sur la surface des objets de la scène. On utilise la triangulation de Delaunay pour fournir une approximation polyhédrique des scènes.
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Wang, Yang. "Hybrid approaches for mobile robot navigation." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/8017.
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The work described in this thesis contributes to the efficient solution of mobile robot navigation problems. A series of new evolutionary approaches is presented. Two novel evolutionary planners have been developed that reduce the computational overhead in generating plans of mobile robot movements. In comparison with the best-performing evolutionary scheme reported in the literature, the first of the planners significantly reduces the plan calculation time in static environments. The second planner was able to generate avoidance strategies in response to unexpected events arising from the presence of moving obstacles. To overcome limitations in responsiveness and the unrealistic assumptions regarding a priori knowledge that are inherent in planner-based and a vigation systems, subsequent work concentrated on hybrid approaches. These included a reactive component to identify rapidly and autonomously environmental features that were represented by a small number of critical waypoints. Not only is memory usage dramatically reduced by such a simplified representation, but also the calculation time to determine new plans is significantly reduced. Further significant enhancements of this work were firstly, dynamic avoidance to limit the likelihood of potential collisions with moving obstacles and secondly, exploration to identify statistically the dynamic characteristics of the environment. Finally, by retaining more extensive environmental knowledge gained during previous navigation activities, the capability of the hybrid navigation system was enhanced to allow planning to be performed for any start point and goal point.
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Wong, Chee Kit. "Cognitive inspired mapping by an autonomous mobile robot." Click here to access this resource online, 2008. http://hdl.handle.net/10292/427.
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When animals explore a new environment, they do not acquire a precise map of the places visited. In fact, research has shown that learning is a recurring process. Over time, new information helps the animal to update their perception of the locations it has visited. Yet, they are still able to use the fuzzy and often incomplete representation to find their way home. This process has been termed the cognitive mapping process. The work presented in this thesis uses a mobile robot equipped with sonar sensors to investigate the nature of such a process. Specifically, what is the information that is fundamental and prevalent in spatial navigation? Initially, the robot is instructed to compute a “cognitive map” of its environment. Since a robot is not a cognitive agent, it cannot, by definition, compute a cognitive map. Hence the robot is used as a test bed for understanding the cognitive mapping process. Yeap’s (1988) theory of cognitive mapping forms the foundation for computing the robot’s representation of the places it has visited. He argued that a network of local spaces is computed early in the cognitive mapping process. Yeap coined these local spaces as Absolute Space Representations (ASRs). However, ASR is not just a process of partitioning the environment into smaller local regions. The ASRs describe the bounded space that one is in, how one could leave that space (exits) and how the exits serves to link the ASRs to form a network that serves as the cognitive map (see Jefferies (1999)). Like the animal’s cognitive map, ASRs are not precise geometrical maps of the environment but rather, provide a rough shape or feel of the space the robot is currently in. Once the robot computes its “cognitive map”, it is then, like foraging and hoarding animals, instructed to find its way home. To do so, the robot uses two crucial pieces of information: distance between exits of ASRs and relative orientation of adjacent ASRs. A simple animal-like strategy was implemented for the robot to locate home. Results from the experiments demonstrated the robot’s ability to determine its location within the visited environment along its journey. This task was performed without the use of an accurate map. From these results and reviews of various findings related to cognitive mapping for various animals, we deduce that: Different animals have different sensing capabilities. They live in different environments and therefore face unique challenges. Consequently, they evolve to have different navigational strategies. However, we believe two crucial pieces of information are inherent in all animals and form the fundamentals of navigation: distance and orientation. Higher level animals may encode and may even prefer richer information to enhance the animal’s cognitive map. Nonetheless, distance and orientation will always be computed as a core process of cognitive mapping. We believe this insight will help future research to better understand the complex nature of cognitive mapping.
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Aguilar, Jeffrey Jose. "Exploring lift-off dynamics in a jumping robot." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45961.
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We study vertical jumping in a simple robot comprising an actuated mass spring arrangement. The actuator frequency and phase are systematically varied to find optimal performance. Optimal jumps occur above and below (but not at) the robot's resonant frequency f0. Two distinct jumping modes emerge: a simple jump which is optimal above f0 is achievable with a squat maneuver, and a peculiar stutter jump which is optimal below f0 is generated with a countermovement. A simple dynamical model reveals how optimal lift-off results from non-resonant transient dynamics.
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Nguyen, Hai Dai. "Constructing mobile manipulation behaviors using expert interfaces and autonomous robot learning." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50206.
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With current state-of-the-art approaches, development of a single mobile manipulation capability can be a labor-intensive process that presents an impediment to the creation of general purpose household robots. At the same time, we expect that involving a larger community of non-roboticists can accelerate the creation of new novel behaviors. We introduce the use of a software authoring environment called ROS Commander (ROSCo) allowing end-users to create, refine, and reuse robot behaviors with complexity similar to those currently created by roboticists. Akin to Photoshop, which provides end-users with interfaces for advanced computer vision algorithms, our environment provides interfaces to mobile manipulation algorithmic building blocks that can be combined and configured to suit the demands of new tasks and their variations.
As our system can be more demanding of users than alternatives such as using kinesthetic guidance or learning from demonstration, we performed a user study with 11 able-bodied participants and one person with quadriplegia to determine whether computer literate non-roboticists will be able to learn to use our tool. In our study, all participants were able to successfully construct functional behaviors after being trained. Furthermore, participants were able to produce behaviors that demonstrated a variety of creative manipulation strategies, showing the power of enabling end-users to author robot behaviors.
Additionally, we introduce how using autonomous robot learning, where the robot captures its own training data, can complement human authoring of behaviors by freeing users from the repetitive task of capturing data for learning. By taking advantage of the robot's embodiment, our method creates classifiers that predict using visual appearances 3D locations on home mechanisms where user constructed behaviors will succeed. With active learning, we show that such classifiers can be learned using a small number of examples. We also show that this learning system works with behaviors constructed by non-roboticists in our user study. As far as we know, this is the first instance of perception learning with behaviors not hand-crafted by roboticists.