1,720,956 research outputs found
A Shared Telemanipulation Interface to Facilitate Bimanual Grasping and Transportation of Objects of Unknown Mass
No full textThe teleoperation of robots with human-like capabilities may pose significant challenges to the human operator due to the kinematic complexity and redundancy of these robots. Bimanual telemanipulation represents such a challenging task that requires precise coordination of the two arms to perform a stable bimanual grasp on an object and eventually transport the object while maintaining the grasp.In this work, we present a shared control telemanipulation interface to facilitate the bimanual grasping and transportation of objects of unknown mass. With the proposed method, the robot is able to transport the object maintaining autonomously a sufficient amount of grasping force while accepting commands from the operator to reach the desired location. As humans do, it is not necessary to know the weight of the object in advance; instead, the robot estimates it during the lifting phase. On the basis of the estimated weight, the required amount of grasping force is computed. During object transportation, the robot autonomously regulates the grasping forces in a shared control fashion, allowing the operator to seamlessly command only the trajectories of the object.The proposed method has been implemented and validated on the CENTAURO robot, a quadrupedal platform with a humanoid dual arm upper body, performing experiment where objects of different weights and dimensions must be picked up and transported
Towards an Open-Source Hardware Agnostic Framework for Robotic End-Effectors Control
No full textNowadays a wide range of industrial grippers are available on the market and usually their integration to robotics automation systems relies on dedicated software modules and interfaces specific for each gripper. During the past two decades, more sophisticated end-effector modules that target to provide additional functionality including dexterous manipulation skills as well as sensing capabilities have been developed. The integration of these new devices is usually not trivial, requiring the development of brand new, tailor-made software modules and interfaces, which is a time consuming and certainly not efficient activity. To address the above issue and facilitate the quick integration and validation of the new end-effectors, we developed the ROS End-Effector open-source framework, which provides a software infrastructure capable to accommodate a range of robotic end-effectors of different hardware characteristics (number of fingers, actuators, sensing modules and communication protocols) and capabilities (with different manipulation skills, such as grasping, pinching, or independent finger dexterity) effectively facilitating their integration through the development of hardware agnostic software modules, simulation tools and application programming interfaces (APIs). A key feature of the ROS End-Effector framework is that rather than controlling each end-effector in a different and customized way, following specific protocols and instructions data fields, it masks the physical hardware differences and limitations (e.g., kinematics and dynamic model, actuator, sensor, update frequency, etc.) and permits to command the end-effector using a set of high level grasping primitives. The framework capabilities and flexibility in supporting different robotics end-effectors are demonstrated both in a kinematic/dynamic simulation and in real hardware experiments
TelePhysicalOperation: Remote Robot Control Based on a Virtual "Marionette" Type Interaction Interface
No full textTeleoperation permits to control robots from a safe distance while performing tasks in a remote environment. Kinematic differences between the input device and the remotely controlled manipulator or the existence of redundancy in the remote robot may pose challenges in moving intuitively the remote robot as desired by the human operator. Motivated by the above challenges, this work introduces TelePhysicalOperation, a novel teloperation concept, which relies on a virtual physical interaction interface between the human operator and the remote robot in a manner that is equivalent to a "Marionette" based interaction interface. With the proposed approach, the user can virtually "interact" with the remote robot, through the application of virtual forces, which are generated by the operator tracking system and can be then selectively applied to any body part of the remote robot along its kinematic chain. This leads to the remote robot generating motions that comply with the applied virtual forces, thanks to the underlying control architecture. The proposed method permits to command the robot from a distance by exploring the intuitiveness of the "Marionette" based physical interaction with the robot in a virtual/remote manner. The details of the proposed approach are introduced and its effectiveness is demonstrated through a number of experimental trials executed on the CENTAURO, a hybrid leg-wheel platform with an anthropomorphic upper body
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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