183 research outputs found

    Data-Driven Grasp Synthesis - A Survey

    Full text link
    We review the work on data-driven grasp synthesis and the methodologies for sampling and ranking candidate grasps. We divide the approaches into three groups based on whether they synthesize grasps for known, familiar or unknown objects. This structure allows us to identify common object representations and perceptual processes that facilitate the employed data-driven grasp synthesis technique. In the case of known objects, we concentrate on the approaches that are based on object recognition and pose estimation. In the case of familiar objects, the techniques use some form of a similarity matching to a set of previously encountered objects. Finally for the approaches dealing with unknown objects, the core part is the extraction of specific features that are indicative of good grasps. Our survey provides an overview of the different methodologies and discusses open problems in the area of robot grasping. We also draw a parallel to the classical approaches that rely on analytic formulations.Comment: 20 pages, 30 Figures, submitted to IEEE Transactions on Robotic

    Fuzzy optimisation based symbolic grounding for service robots

    Get PDF
    A thesis submitted to the University of Bedfordshire in partial fulfilment of the requirements for the degree of Doctor of PhilosophySymbolic grounding is a bridge between task level planning and actual robot sensing and actuation. Uncertainties raised by unstructured environments make a bottleneck for integrating traditional artificial intelligence with service robotics. In this research, a fuzzy optimisation based symbolic grounding approach is presented. This approach can handle uncertainties and helps service robots to determine the most comfortable base region for grasping objects in a fetch and carry task. Novel techniques are applied to establish fuzzy objective function, to model fuzzy constraints and to perform fuzzy optimisation. The approach does not have the short comings of others’ work and the computation time is dramatically reduced in compare with other methods. The advantages of the proposed fuzzy optimisation based approach are evidenced by experiments that were undertaken in Care-O-bot 3 (COB 3) and Robot Operating System (ROS) platforms

    Workspace and singularity determination of a 7-DoF wrist-partitioned serial manipulator towards graffiti painting

    Get PDF
    Els robots estan sent utilitzats, cada cop més, en la realització de tasques en la indústria. Molts d'ells també són dissenyats pensats per a realitzar les tasques de la llar. En general, els robots són dissenyats per a facilitar el dia a dia del éssers humans. Però quan es tracta d'obres artístiques, és menys comú trobar-se robots realitzant-les. Nosaltres pretenem sortir de la norma mitjançant l'ús d'un robot per a pintar un grafiti. La motivació per a aconseguir-ho convergeix en la formulació de dues preguntes: "Quin és el volum de treball d'un robot, quan l'orientació del seu efector final està fixada?" i "Donat un pla arbitrari, quina és la major àrea de treball lliure de singularitats en aquest?" Aquesta tesi proposa un mètode per a l'obtenció de les singularitats de posició en un pla qualsevol d'un manipulador serial amb un canell esfèric. El mètode s'ha obtingut mitjançant la combinació d'un mètode de determinació de singularitats de posició, el qual està basat en una tècnica per al decoplat de manipuladors que presenten un canell esfèric, i un algorisme branch-and-prune per a la resolució de sistemes d'equacions. S'ha obtingut el volum de treball d'un manipulador serial de 7 graus de llibertat a través d'un enfocament de cinemàtica directa. Es presenta una metodologia per a obtenir el volum de treball del manipulador serial quan el seu efector final té l'orientació constant i s'aplica per a obtenir aproximacions per al cas de certes orientacions. Es mostra com les singularitats poden ser analitades a través de separar-les en singularitats de posició i d'orientació. el mètode proposat formula i resol les equacions que determinen les singularitats de posició. Pel que fa a les singularitats d'orientació, es mostra que poden ser evitades sense perdre una quantitat significant de volum de treball, des del punt de vista de la posició.Los robots estén siendo utilizados, cada vez más, en la realización de tareas en la industria. Muchos de ellos también son diseñados pensados para realizar las tareas del hogar. En general, los robots son diseñados para facilitar el día a día de los seres humanos. Pero cuando se trata de obras artíticas, es menos común encontrarse a robots realizándolas. Nosotros pretendemos salirnos de lo común mediante el uso de un robot para pintar un grafiti. La motivación por lograrlo converge en la formulación de dos preguntas: "¿Cuál es el volumen de trabajo de un robot, cuando la orientación de su efector final está fijada?" y "Dado un plano arbitrario, ¿cuál es la mayor área de trabajo libre de singularidades en éste?" Esta tesis propone un método para la obtención de las singularidades de posición en un plano cualquiera de un manipulador serial con una muñeca esférica. El método ha sido obtenido mediante la combinación de un método de determinación de singularidades de posición, el cual está basado en una técnica para el decoplado de manipuladores que presentan una muñeca esférica, y un algoritmo branch-and-prune para la resolución de sistemas de ecuaciones. Se ha obtenido el volumen de trabajo de un manipulador serial de 7 grados de libertad a través de un enfoque de cinemática directa. Se presenta la metodología para obtener el volumen de trabajo del manipulador serial cuando su efector final tiene una orientación constante y se aplica para obtener aproximaciones para el caso de ciertas orientaciones. Se muestra cómo las singularidades pueden ser analizadas a través de separarlas en singularidades de posición y de orientación. El método propuesto formula y resuelve las ecuaciones que determinan las singularidades de posición. En cuanto a las singularidades de orientación, se muestra que pueden ser evitadas sin perder una cantidad significante de volumen de trabajo, desde el punto de vista de la posición.Robots are overtaking every day more tasks in the industry. A lot of them are even designed for performing household chores. In general, robots are designed to facilitate the day-to-day of human beings. But when it comes to artistic tasks, it is less usual to see robots performing them. We pretend to stay out of the crowd by using a robot to paint a graffiti. The motivation to achieve this task converges into the statement of two questions: "What is the workspace of a robot, when the orientation of its end-effector is fixed?" and "For a given plane, what is the largest singularity free surface on it?". This thesis proposes a method for the computation of the position singularities of a wrist-partitioned serial manipulator for a given plane. The method is obtained from the combination of a position singularity determination method, which is based on the decoupling technique of a wrist-partitioned manipulator, and a branch-and-prune algorithm for the resolution of systems of equations. The workspace of a 7-DoF serial manipulator is obtained by a forward kinematics approach. A methodology to obtain the constant orientation workspace of a serial manipulator is presented and applied to get approximations for some specific orientations. It is shown how singularities can be analyzed by decoupling them into position singularities and orientation singularities. The proposed method formulates and solves the equation that determines the position singularities. In the case of the orientation singularities, it is shown that they can be avoided without losing a significant amount of the workspace's volume, from the point of view of the position.Outgoin

    On-the-Fly Workspace Visualization for Redundant Manipulators

    Get PDF
    This thesis explores the possibilities of on-line workspace rendering for redundant robotic manipulators via parallelized computation on the graphics card. Several visualization schemes for different workspace types are devised, implemented and evaluated. Possible applications are visual support for the operation of manipulators, fast workspace analyses in time-critical scenarios and interactive workspace exploration for design and comparison of robots and tools

    Advances in flexible manipulation through the application of AI-based techniques

    Get PDF
    282 p.Objektuak hartu eta uztea oinarrizko bi eragiketa dira ia edozein aplikazio robotikotan. Gaur egun, "pick and place" aplikazioetarako erabiltzen diren robot industrialek zeregin sinpleak eta errepikakorrak egiteko duten eraginkortasuna dute ezaugarri. Hala ere, sistema horiek oso zurrunak dira, erabat kontrolatutako inguruneetan lan egiten dute, eta oso kostu handia dakarte beste zeregin batzuk egiteko birprogramatzeak. Gaur egun, industria-ingurune desberdinetako zereginak daude (adibidez, logistika-ingurune batean eskaerak prestatzea), zeinak objektuak malgutasunez manipulatzea eskatzen duten, eta oraindik ezin izan dira automatizatu beren izaera dela-eta. Automatizazioa zailtzen duten botila-lepo nagusiak manipulatu beharreko objektuen aniztasuna, roboten trebetasun falta eta kontrolatu gabeko ingurune dinamikoen ziurgabetasuna dira.Adimen artifizialak (AA) gero eta paper garrantzitsuagoa betetzen du robotikaren barruan, robotei zeregin konplexuak betetzeko beharrezko adimena ematen baitie. Gainera, AAk benetako esperientzia erabiliz portaera konplexuak ikasteko aukera ematen du, programazioaren kostua nabarmen murriztuz. Objektuak manipulatzeko egungo sistema robotikoen mugak ikusita, lan honen helburu nagusia manipulazio-sistemen malgutasuna handitzea da AAn oinarritutako algoritmoak erabiliz, birprogramatu beharrik gabe ingurune dinamikoetara egokitzeko beharrezko gaitasunak emanez

    Affordances in Psychology, Neuroscience, and Robotics: A Survey

    Get PDF
    The concept of affordances appeared in psychology during the late 60s as an alternative perspective on the visual perception of the environment. It was revolutionary in the intuition that the way living beings perceive the world is deeply influenced by the actions they are able to perform. Then, across the last 40 years, it has influenced many applied fields, e.g., design, human-computer interaction, computer vision, and robotics. In this paper, we offer a multidisciplinary perspective on the notion of affordances. We first discuss the main definitions and formalizations of the affordance theory, then we report the most significant evidence in psychology and neuroscience that support it, and finally we review the most relevant applications of this concept in robotics

    Robot Navigation in Human Environments

    Get PDF
    For the near future, we envision service robots that will help us with everyday chores in home, office, and urban environments. These robots need to work in environments that were designed for humans and they have to collaborate with humans to fulfill their tasks. In this thesis, we propose new methods for communicating, transferring knowledge, and collaborating between humans and robots in four different navigation tasks. In the first application, we investigate how automated services for giving wayfinding directions can be improved to better address the needs of the human recipients. We propose a novel method based on inverse reinforcement learning that learns from a corpus of human-written route descriptions what amount and type of information a route description should contain. By imitating the human teachers' description style, our algorithm produces new route descriptions that sound similarly natural and convey similar information content, as we show in a user study. In the second application, we investigate how robots can leverage background information provided by humans for exploring an unknown environment more efficiently. We propose an algorithm for exploiting user-provided information such as sketches or floor plans by combining a global exploration strategy based on the solution of a traveling salesman problem with a local nearest-frontier-first exploration scheme. Our experiments show that the exploration tours are significantly shorter and that our system allows the user to effectively select the areas that the robot should explore. In the second part of this thesis, we focus on humanoid robots in home and office environments. The human-like body plan allows humanoid robots to navigate in environments and operate tools that were designed for humans, making humanoid robots suitable for a wide range of applications. As localization and mapping are prerequisites for all navigation tasks, we first introduce a novel feature descriptor for RGB-D sensor data and integrate this building block into an appearance-based simultaneous localization and mapping system that we adapt and optimize for the usage on humanoid robots. Our optimized system is able to track a real Nao humanoid robot more accurately and more robustly than existing approaches. As the third application, we investigate how humanoid robots can cover known environments efficiently with their camera, for example for inspection or search tasks. We extend an existing next-best-view approach by integrating inverse reachability maps, allowing us to efficiently sample and check collision-free full-body poses. Our approach enables the robot to inspect as much of the environment as possible. In our fourth application, we extend the coverage scenario to environments that also include articulated objects that the robot has to actively manipulate to uncover obstructed regions. We introduce algorithms for navigation subtasks that run highly parallelized on graphics processing units for embedded devices. Together with a novel heuristic for estimating utility maps, our system allows to find high-utility camera poses for efficiently covering environments with articulated objects. All techniques presented in this thesis were implemented in software and thoroughly evaluated in user studies, simulations, and experiments in both artificial and real-world environments. Our approaches advance the state of the art towards universally usable robots in everyday environments.Roboternavigation in menschlichen Umgebungen In naher Zukunft erwarten wir Serviceroboter, die uns im Haushalt, im Büro und in der Stadt alltägliche Arbeiten abnehmen. Diese Roboter müssen in für Menschen gebauten Umgebungen zurechtkommen und sie müssen mit Menschen zusammenarbeiten um ihre Aufgaben zu erledigen. In dieser Arbeit schlagen wir neue Methoden für die Kommunikation, Wissenstransfer und Zusammenarbeit zwischen Menschen und Robotern bei Navigationsaufgaben in vier Anwendungen vor. In der ersten Anwendung untersuchen wir, wie automatisierte Dienste zur Generierung von Wegbeschreibungen verbessert werden können, um die Beschreibungen besser an die Bedürfnisse der Empfänger anzupassen. Wir schlagen eine neue Methode vor, die inverses bestärkendes Lernen nutzt, um aus einem Korpus von von Menschen geschriebenen Wegbeschreibungen zu lernen, wie viel und welche Art von Information eine Wegbeschreibung enthalten sollte. Indem unser Algorithmus den Stil der Wegbeschreibungen der menschlichen Lehrer imitiert, kann der Algorithmus neue Wegbeschreibungen erzeugen, die sich ähnlich natürlich anhören und einen ähnlichen Informationsgehalt vermitteln, was wir in einer Benutzerstudie zeigen. In der zweiten Anwendung untersuchen wir, wie Roboter von Menschen bereitgestellte Hintergrundinformationen nutzen können, um eine bisher unbekannte Umgebung schneller zu erkunden. Wir schlagen einen Algorithmus vor, der Hintergrundinformationen wie Gebäudegrundrisse oder Skizzen nutzt, indem er eine globale Explorationsstrategie basierend auf der Lösung eines Problems des Handlungsreisenden kombiniert mit einer lokalen Explorationsstrategie. Unsere Experimente zeigen, dass die Erkundungstouren signifikant kürzer werden und dass der Benutzer mit unserem System effektiv die zu erkundenden Regionen spezifizieren kann. Der zweite Teil dieser Arbeit konzentriert sich auf humanoide Roboter in Umgebungen zu Hause und im Büro. Der menschenähnliche Körperbau ermöglicht es humanoiden Robotern, in Umgebungen zu navigieren und Werkzeuge zu benutzen, die für Menschen gebaut wurden, wodurch humanoide Roboter für vielfältige Aufgaben einsetzbar sind. Da Lokalisierung und Kartierung Grundvoraussetzungen für alle Navigationsaufgaben sind, führen wir zunächst einen neuen Merkmalsdeskriptor für RGB-D-Sensordaten ein und integrieren diesen Baustein in ein erscheinungsbasiertes simultanes Lokalisierungs- und Kartierungsverfahren, das wir an die Besonderheiten von humanoiden Robotern anpassen und optimieren. Unser System kann die Position eines realen humanoiden Roboters genauer und robuster verfolgen, als es mit existierenden Ansätzen möglich ist. Als dritte Anwendung untersuchen wir, wie humanoide Roboter bekannte Umgebungen effizient mit ihrer Kamera abdecken können, beispielsweise zu Inspektionszwecken oder zum Suchen eines Gegenstands. Wir erweitern ein bestehendes Verfahren, das die nächstbeste Beobachtungsposition berechnet, durch inverse Erreichbarkeitskarten, wodurch wir kollisionsfreie Ganzkörperposen effizient generieren und prüfen können. Unser Ansatz ermöglicht es dem Roboter, so viel wie möglich von der Umgebung zu untersuchen. In unserer vierten Anwendung erweitern wir dieses Szenario um Umgebungen, die auch bewegbare Gegenstände enthalten, die der Roboter aktiv bewegen muss um verdeckte Regionen zu sehen. Wir führen Algorithmen für Teilprobleme ein, die hoch parallelisiert auf Grafikkarten von eingebetteten Systemen ausgeführt werden. Zusammen mit einer neuen Heuristik zur Schätzung von Nutzenkarten ermöglicht dies unserem System Beobachtungspunkte mit hohem Nutzen zu finden, um Umgebungen mit bewegbaren Objekten effizient zu inspizieren. Alle vorgestellten Techniken wurden in Software implementiert und sorgfältig evaluiert in Benutzerstudien, Simulationen und Experimenten in künstlichen und realen Umgebungen. Unsere Verfahren bringen den Stand der Forschung voran in Richtung universell einsetzbarer Roboter in alltäglichen Umgebungen

    Humanoid Robots

    Get PDF
    For many years, the human being has been trying, in all ways, to recreate the complex mechanisms that form the human body. Such task is extremely complicated and the results are not totally satisfactory. However, with increasing technological advances based on theoretical and experimental researches, man gets, in a way, to copy or to imitate some systems of the human body. These researches not only intended to create humanoid robots, great part of them constituting autonomous systems, but also, in some way, to offer a higher knowledge of the systems that form the human body, objectifying possible applications in the technology of rehabilitation of human beings, gathering in a whole studies related not only to Robotics, but also to Biomechanics, Biomimmetics, Cybernetics, among other areas. This book presents a series of researches inspired by this ideal, carried through by various researchers worldwide, looking for to analyze and to discuss diverse subjects related to humanoid robots. The presented contributions explore aspects about robotic hands, learning, language, vision and locomotion
    • …
    corecore