• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1204
  • 263
  • 234
  • 204
  • 181
  • 114
  • 36
  • 34
  • 20
  • 18
  • 13
  • 13
  • 9
  • 9
  • 7
  • Tagged with
  • 2781
  • 570
  • 544
  • 522
  • 483
  • 415
  • 408
  • 393
  • 351
  • 290
  • 260
  • 252
  • 215
  • 213
  • 213
  • 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.
351

Development of a prototype for a game including an industrial robot

Guijarro Chirosa, María del Sol January 2009 (has links)
<p>The aim of this essay is to describe the development of two prototypes, a physical one and a computer one, for a ball game involving interaction with an industrial robot.The purpose of the game is to attract young people, especially young women, to engineering, for amusement or education, at exhibitions or other student environments.</p><p>This project in Product Design Engineering was initiated by the Centre for Intelligent Automation, a research group of Skövde University who offered the task in cooperation with two other areas of engineering, i.e Automation Engineering and Computer Science.</p><p>The entire robot game project was developed by a five-woman team, which resulted in three different projects belonging to each study. The design engineering task was carried out by analysing the component needs, taking in consideration all the important factors involved, to recognize problems and limitations, and focus on prototypes. The development process included concept generation and evaluation, prototyping and detail design and testing and refinement of the physical prototype. As a result the prototype showed an intuitive way to play the game, and a 3D CAD model was developed to show an alternative design which found solutions to some of the problems shown by the physical one.</p>
352

Design of a Pivotally Tool Holder

Voxberg, Joel, Persson, Johan January 2008 (has links)
<p>Ljunghäll AB in Södra Vi has many industrial robots in their casting production. These</p><p>robots have a tendency to wear out. The purpose with this thesis was to design a toolholder</p><p>that was able flip to a 90 degree angle to get a more flexible production but also to</p><p>lessen the wear on the robot.</p><p>Parts of David G. Ullman and Ulf Liedholm’s design processes was used as a base for</p><p>the solutions and the conceptual design.</p><p>A number of concepts where made and one of them evaluated to be a refined concept.</p><p>The result became a tool-holder that used an air-motor and two spur gears to rotate the</p><p>plate where the tool is mounted to a 90 degree angle. According to the calculations that was</p><p>made, both by hand and by the computer program COSMOS, the concept should work</p><p>in practice. A prototype ought to be made to guarantee the function of the concept.</p>
353

Robots parallèles à nacelle articulée, du concept à la solution industrielle pour le pick-andplace

Nabat, Vincent 02 March 2007 (has links) (PDF)
Les applications de pick-and-place à hautes cadences requièrent des caractéristiques très élevées en terme de performances dynamiques, que seuls les robots parallèles sont capables d'atteindre. Les robots à quatre degrés de liberté proposent le plus de flexibilité, mais l'amplitude de la rotation permettant l'orientation de l'objet est souvent le point faible de ces architectures. Cependant, le concept de nacelle articulée permet de dépasser cet inconvénient. Ainsi, trois nouvelles architectures de robots de pick-and-place à quatre degrés de liberté sont présentées dans ce manuscrit : les architectures Par4, Héli4 et Dual4. Pour chacun des robots présentés, une étude complète est effectuée et un démonstrateur est réalisé afin de valider les concepts et de les évaluer. Une méthode de modélisation dynamique simplifiée appliquée aux robots à nacelle articulée est ensuite présentée. Cette méthode est appliquée au robot Par4 et permet de mettre en avant un déséquilibre des couples moteurs sur ce mécanisme. Il est alors démontré qu'un changement mineur dans la cinématique de la nacelle permet de réduire de 30% les couples mis en jeux lors de trajectoires de prises-déposes. Une nouvelle version "équilibrée" du robot est donc proposée en se fondant sur l'étude dynamique présentée précédemment. Enfin, deux types d'optimisations appliquées aux robots de pick-and-place sont présentés. Tout d'abord, une méthode de recherche des paramètres géométriques dédiée aux robots de pick-and-place est présentée et appliquée au robot Par4. De plus, une génération de trajectoire utilisant les clothoïdes et une loi horaire adaptative est proposée afin d'optimiser les déplacements du robot lors de mouvements de pick-and-place à très hautes accélérations
354

Spacecraft pose estimation via a cascading genetic algorithm /

Obsniuk, Mark. January 2006 (has links)
Thesis (M.Sc.)--York University, 2006. Graduate Programme in Computer Science. / Typescript. Includes bibliographical references (leaves 157-162). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR29596
355

Hybrid force and position control in robotic surface processing

Steven, Andrew January 1989 (has links)
This programme of research was supported by NEI Parsons Ltd. who sought a robotic means of polishing mechanical components. A study of the problems associated with robot controlled surface processing is presented. From this evolved an approach consistent with the formalisation of the demands of workpiece manipulation which included the adoption of the Hybrid robot control scheme capable of simultaneous force and position control. A unique 3 axis planar experimental manipulator was designed which utilized combined parallel and serial drives. A force sensing wrist was used to measure contact force. A variant of the Hybrid control 'scheme was successfully implemented on a twin computer control system. A number of manipulator control programs are presented. The force control aspect is shown both experimentally and analytically to present control problems and the research has concentrated on this aspect. A general analysis of the dynamics of force control is given which shows force response to be dependent on a number' of important parameters including force sensor, environment and manipulator dynamics. The need for a robust or adaptable force controller is discussed. A series of force controlled manipulator experiments is described and the results discussed in the context of general analyses and specific single degree of freedom simulations. Improvements to manipulator force control are suggested and some were implemented. These are discussed together with their immediate application to the improvement of robot controlled surface processing. This work also lays important foundations for long term related research. In particular the new techniques for actively controlled assembly and force control under 'fast' operation.
356

Fast biped walking with a neuronal controller and physical computation

Geng, Tao January 2007 (has links)
Biped walking remains a difficult problem and robot models can greatly {facilitate} our understanding of the underlying biomechanical principles as well as their neuronal control. The goal of this study is to specifically demonstrate that stable biped walking can be achieved by combining the physical properties of the walking robot with a small, reflex-based neuronal network, which is governed mainly by local sensor signals. This study shows that human-like gaits emerge without {specific} position or trajectory control and that the walker is able to compensate small disturbances through its own dynamical properties. The reflexive controller used here has the following characteristics, which are different from earlier approaches: (1) Control is mainly local. Hence, it uses only two signals (AEA=Anterior Extreme Angle and GC=Ground Contact) which operate at the inter-joint level. All other signals operate only at single joints. (2) Neither position control nor trajectory tracking control is used. Instead, the approximate nature of the local reflexes on each joint allows the robot mechanics itself (e.g., its passive dynamics) to contribute substantially to the overall gait trajectory computation. (3) The motor control scheme used in the local reflexes of our robot is more straightforward and has more biological plausibility than that of other robots, because the outputs of the motorneurons in our reflexive controller are directly driving the motors of the joints, rather than working as references for position or velocity control. As a consequence, the neural controller and the robot mechanics are closely coupled as a neuro-mechanical system and this study emphasises that dynamically stable biped walking gaits emerge from the coupling between neural computation and physical computation. This is demonstrated by different walking experiments using two real robot as well as by a Poincar\' map analysis applied on a model of the robot in order to assess its stability. In addition, this neuronal control structure allows the use of a policy gradient reinforcement learning algorithm to tune the parameters of the neurons in real-time, during walking. This way the robot can reach a record-breaking walking speed of 3.5 leg-lengths per second after only a few minutes of online learning, which is even comparable to the fastest relative speed of human walking.
357

Design of an Autonomous Robot for Indoor Navigation

McConnell, Michael, Chionuma, Daniel, Wright, Jordan, Brandt, Jordan, Zhe, Liu 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / This paper describes the design and implementation of an autonomous robot to navigate indoors to a specified target using an inexpensive commercial off the shelf USB camera and processor running an imbedded Linux system. The robot identifies waypoints to aid in navigation, which in our case consists of a series of quick response (QR) codes. Using a 1080p USB camera, the robot could successfully identify waypoints at a distance of over 4 meters, and navigate at a rate of 50 cm/sec.
358

Localization of a mobile robot by monocular vision

李宏釗, Li, Wan-chiu. January 2001 (has links)
published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy
359

Ολοκληρωμένο σύστημα οδομετρίας για κινούμενα ρομπότ με χρήση μετρήσεων από πολλαπλούς αισθητήρες / Integrated robotic odometry system using sensor data fusion

Κελασίδη, Ελένη 10 June 2009 (has links)
Στόχος της παρούσας διπλωματικής εργασίας είναι η ανάπτυξη ολοκληρωμένου συστήματος οδομετρίας που θα υπολογίζει την απόσταση μετακίνησης ενός κινητού μέσου με χρήση τεχνικών όρων της όρασης των υπολογιστών. Στα κλασικά μετρητικά συστήματα εμφανίζονται σημαντικές αποκλίσεις μεταξύ της πραγματικής και της υπολογισθείσας θέσης του ρομπότ. Σκοπός της ολοκληρωμένης διάταξης οδομετρίας που θα κατασκευαστεί είναι ο περιορισμός των σφαλμάτων αυτών. / Aim of this diploma thesis is the development of a dead-reackoning (odometry) system through a hollistic approach, in order to calculate the distance travelled by a mobile system (robot) by means of computer vision. In traditional systems there exist important deviations between the real and the calculated positions. Goal of the current work is to limit (minimize) the aforementioned deviations.
360

A Multi-Robot Coordination Methodology for Wilderness Search and Rescue

Macwan, Ashish 13 January 2014 (has links)
One of the applications where the use of robots can be beneficial is Wilderness Search and Rescue (WiSAR), which involves the search for a possibly mobile but non-trackable lost person (i.e., the target) in wilderness environments. A mobile target implies that the search area grows continuously and potentially without bound. This fact, combined with the presence of typically rugged, varying terrain and the possibility of inclement weather, poses a considerable challenge to human Search and Rescue (SAR) personnel with respect to the time and effort required to perform the search and the danger entailed to the searchers. Mobile robots can be advantageous in WiSAR due to their ability to provide consistent performance without getting tired and their lower susceptibility to harsh weather conditions compared to humans. Thus, a coordinated team of robots that can assist human SAR personnel by autonomously performing searches in WiSAR scenarios would be of great value. However, to date, a suitable multi-robot coordination methodology for autonomous search that can satisfactorily address the issues relevant to WiSAR is lacking. The objective of this Dissertation is, thus, to develop a methodology that can autonomously coordinate the search strategy of a multi-robot team in wilderness environments to locate a moving target that is neither continuously nor intermittently observed during the search process. Three issues in particular are addressed: (i) target-location prediction, (ii) robot deployment, and (iii) robot-path planning. The corresponding solution approaches devised to address these issues incorporate the influence of varying terrain that may contain a priori known and unknown obstacles, and deal with unique target physiology and psychology as well as found clues left behind by the target. The solution methods for these three tasks work seamlessly together resulting in a tractable MRC methodology for autonomous robotic WiSAR. Comprehensive simulations have been performed that validate the overall proposed methodology. Moreover, the tangible benefits provided by this methodology were further revealed through its comparison with an alternative search method.

Page generated in 0.0343 seconds