1,494 research outputs found

    The KIT swiss knife gripper for disassembly tasks: a multi-functional gripper for bimanual manipulation with a single arm

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    © 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This work presents the concept of a robotic gripper designed for the disassembly of electromechanical devices that comprises several innovative ideas. Novel concepts include the ability to interchange built-in tools without the need to grasp them, the ability to reposition grasped objects in-hand, the capability of performing classic dual arm manipulation within the gripper and the utilization of classic industrial robotic arms kinematics within a robotic gripper. We analyze state of the art grippers and robotic hands designed for dexterous in-hand manipulation and extract common characteristics and weak points. The presented concept is obtained from the task requirements for disassembly of electromechanical devices and it is then evaluated for general purpose grasping, in-hand manipulation and operations with tools. We further present the CAD design for a first prototype.Peer ReviewedPostprint (author's final draft

    Method and apparatus for positioning a robotic end effector

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    A robotic end effector and operation protocol for a reliable grasp of a target object irrespective of the target's contours is disclosed. A robotic hand includes a plurality of jointed fingers, one of which, like a thumb, is in opposed relation to the other. Each finger is comprised of at least two jointed sections, and provided with reflective proximity sensors, one on the inner surface of each finger section. Each proximity sensor comprises a transmitter of a beam of radiant energy and means for receiving reflections of the transmitted energy when reflected by a target object and for generating electrical signals responsive thereto. On the fingers opposed to the thumb, the proximity sensors on the outermost finger sections are aligned in an outer sensor array and the sensors on the intermediate finger sections and sensors on the innermost finger sections are similarly arranged to form an intermediate sensor array and an inner sensor array, respectively. The invention includes a computer system with software and/or circuitry for a protocol comprising the steps in sequence of: (1) approach axis alignment to maximize the number of outer layer sensors which detect the target; (2) non-contact contour following the target by the robot fingers to minimize target escape potential; and (3) closing to rigidize the target including dynamically re-adjusting the end effector finger alignment to compensate for target motion. A signal conditioning circuit and gain adjustment means are included to maintain the dynamic range of low power reflection signals

    Ground Robotic Hand Applications for the Space Program study (GRASP)

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    This document reports on a NASA-STDP effort to address research interests of the NASA Kennedy Space Center (KSC) through a study entitled, Ground Robotic-Hand Applications for the Space Program (GRASP). The primary objective of the GRASP study was to identify beneficial applications of specialized end-effectors and robotic hand devices for automating any ground operations which are performed at the Kennedy Space Center. Thus, operations for expendable vehicles, the Space Shuttle and its components, and all payloads were included in the study. Typical benefits of automating operations, or augmenting human operators performing physical tasks, include: reduced costs; enhanced safety and reliability; and reduced processing turnaround time

    dexterous gripper for in hand manipulation with embedded object localization algorithm

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    Abstract Since the last decade, thanks to the spreading of the concept of Industry 4.0 and Smart Factory, more and more companies have started to investigate the robotic field looking for reliable solutions aiming at improving the efficiency of assembly lines. Promising technologies are connected to the speeding up of production stages like fast algorithms for object localization, as well as dexterous grippers for manipulation and assembly. Nowadays, most of the solutions for pick and place tasks involve the use of robotic grippers for grasping objects, while robotic manipulators are responsible for their accurate placements. Focusing on the grippers, although their simple structure can be appreciated, it greatly reduces their in-hand manipulation abilities, making unfeasible the twists of grasped objects and their release in a desired pose. As consequence, the efficiency of the pick and place operation is reduced since several adjustments of the robotic arm are required to accomplish the task. In this paper, a novel dexterous gripper coupled with a vision system algorithm for object localization and pose estimation are presented, and their performances in manipulating different objects are discussed. The designed gripper has a symmetrical structure with two finger modules, each one consisting in a couple of linear actuators arranged mutually orthogonal, so the translations in two axis, namely y and z directions, are allowed. As terminal part of each finger there is a revolute joint to whom is attached a fingertip modelled according to the shape of the target objects and easily replaceable. The embedded vision system algorithm adopted estimates position and orientation of the objects on a flat surface, and it coordinates the gripper placement to grasp them. The case study of the handling of a Spanish fan is presented and discussed in details
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