914 research outputs found

    Time independent tracking using 2-D movement flow-based visual servoing

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    In this paper, the so-called 2-D movement flowbased visual servoing system is proposed, which allows the tracking of trajectories planned in the image space. This method is time-independent, which is useful when problems such as obstructions occur during the tracking. This method allows the tracking of image trajectories assuring the correct behaviour in the 3-D space and avoiding the limitations of the time-dependent systems used up to now for tracking trajectories. This aspect has allowed its application to manipulation tasks in which the trajectory can be obstructed during the tracking.This work is partially supported by the Spanish MCYT project “DESAURO: Desensamblado Automático Selectivo para Reciclado mediante Robots Cooperativos y Sistema Multisensorial” (DPI2002-02103)

    Robust visual servoing in 3d reaching tasks

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    This paper describes a novel approach to the problem of reaching an object in space under visual guidance. The approach is characterized by a great robustness to calibration errors, such that virtually no calibration is required. Servoing is based on binocular vision: a continuous measure of the end-effector motion field, derived from real-time computation of the binocular optical flow over the stereo images, is compared with the actual position of the target and the relative error in the end-effector trajectory is continuously corrected. The paper outlines the general framework of the approach, shows how visual measures are obtained and discusses the synthesis of the controller along with its stability analysis. Real-time experiments are presented to show the applicability of the approach in real 3-D applications

    A Multi-Robot Cooperation Framework for Sewing Personalized Stent Grafts

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    This paper presents a multi-robot system for manufacturing personalized medical stent grafts. The proposed system adopts a modular design, which includes: a (personalized) mandrel module, a bimanual sewing module, and a vision module. The mandrel module incorporates the personalized geometry of patients, while the bimanual sewing module adopts a learning-by-demonstration approach to transfer human hand-sewing skills to the robots. The human demonstrations were firstly observed by the vision module and then encoded using a statistical model to generate the reference motion trajectories. During autonomous robot sewing, the vision module plays the role of coordinating multi-robot collaboration. Experiment results show that the robots can adapt to generalized stent designs. The proposed system can also be used for other manipulation tasks, especially for flexible production of customized products and where bimanual or multi-robot cooperation is required.Comment: 10 pages, 12 figures, accepted by IEEE Transactions on Industrial Informatics, Key words: modularity, medical device customization, multi-robot system, robot learning, visual servoing, robot sewin

    Survey of Visual and Force/Tactile Control of Robots for Physical Interaction in Spain

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    Sensors provide robotic systems with the information required to perceive the changes that happen in unstructured environments and modify their actions accordingly. The robotic controllers which process and analyze this sensory information are usually based on three types of sensors (visual, force/torque and tactile) which identify the most widespread robotic control strategies: visual servoing control, force control and tactile control. This paper presents a detailed review on the sensor architectures, algorithmic techniques and applications which have been developed by Spanish researchers in order to implement these mono-sensor and multi-sensor controllers which combine several sensors

    A Multi-Robot Cooperation Framework for Sewing Personalized Stent Grafts

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    This paper presents a multi-robot system for manufacturing personalized medical stent grafts. The proposed system adopts a modular design, which includes: a (personalized) mandrel module, a bimanual sewing module, and a vision module. The mandrel module incorporates the personalized geometry of patients, while the bimanual sewing module adopts a learning-by-demonstration approach to transfer human hand-sewing skills to the robots. The human demonstrations were firstly observed by the vision module and then encoded using a statistical model to generate the reference motion trajectories. During autonomous robot sewing, the vision module plays the role of coordinating multi-robot collaboration. Experiment results show that the robots can adapt to generalized stent designs. The proposed system can also be used for other manipulation tasks, especially for flexible production of customized products and where bimanual or multi-robot cooperation is required.Comment: 10 pages, 12 figures, accepted by IEEE Transactions on Industrial Informatics, Key words: modularity, medical device customization, multi-robot system, robot learning, visual servoing, robot sewin

    Safe cooperation between human operators and visually controlled industrial manipulators

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    Industrial tasks can be improved substantially by making humans and robots collaborate in the same workspace. The main goal of this chapter is the development of a human-robot interaction system which enables this collaboration and guarantees the safety of the human operator. This system is composed of two subsystems: the human tracking system and the robot control system. The human tracking system deals with the precise real-time localization of the human operator in the industrial environment. It is composed of two systems: an inertial motion capture system and an Ultra-WideBand localization system. The robot control system is based on visual servoing. A safety behaviour which stops the normal path tracking of the robot is performed when the robot and the human are too close. This safety behaviour has been implemented through a multi-threaded software architecture in order to share information between both systems. Thereby, the localization measurements obtained by the human tracking system are processed by the robot control system to compute the minimum human-robot distance and determine if the safety behaviour must be activated.Spanish Ministry of Science and Innovation and the Spanish Ministry of Education through the projects DPI2005-06222 and DPI2008-02647 and the grant AP2005-1458

    Visual Servoing

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    The goal of this book is to introduce the visional application by excellent researchers in the world currently and offer the knowledge that can also be applied to another field widely. This book collects the main studies about machine vision currently in the world, and has a powerful persuasion in the applications employed in the machine vision. The contents, which demonstrate that the machine vision theory, are realized in different field. For the beginner, it is easy to understand the development in the vision servoing. For engineer, professor and researcher, they can study and learn the chapters, and then employ another application method
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