43 research outputs found

    A new family of magnetic adhesion based wall-climbing robots

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    This paper is devoted to climbing robots that adhere to the wall through permanent magnetic elements. If the surface on which they adhere is not ferromagnetic, it is necessary for the system to be composed of two subsystems (master and follower carts), arranged in a sandwich configuration, with the surface to climb interposed between the two. However, this configuration does not allow the robot to descend from the wall where it is climbing and to move freely on the floor (because of the presence of the follower). This paper shows how to remove this limitation. In fact, the system is able to automatically detach the follower when the robot has to move on the floor and recover it when it has to climb

    Development of a Chain Climbing Robot and an Automated Ultrasound Inspection System for Mooring Chain Integrity Assessment

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    Mooring chains used to stabilise offshore floating platforms are often subjected to harsh environmental conditions on a daily basis, i.e. high tidal waves, storms etc. Chain breakage can lead to vessel drift and serious damage such as riser rupture, production shutdown and hydrocarbon release. Therefore, integrity assessment of chain links is vital, and regular inspection is mandatory for offshore structures. Currently, structural health monitoring of chain links is conducted using either remotely operated vehicles (ROVs), which are associated with high costs, or by manual means, which increases the risk to human operators. The development of climbing robots for mooring chain applications is still in its infancy due to the operational complexity and geometrical features of the chain. This thesis presents a Cartesian legged magnetic adhesion tracked-wheel crawler robot developed for mooring chain inspection. The crawler robot presented in this study is suitable for mooring chain climbing in air and the technique can be adapted for underwater use. The proposed robot addresses straight mooring chain climbing and a misaligned scenario that is commonly evident in in-situ conditions. The robot can be used as a platform to convey equipment, i.e. tools for non-destructive testing/evaluation applications. The application of ultrasound for in-service mooring chain inspection is still in the early stages due to lack of accessibility, in-field operational complexity and the geometrical features of mooring systems. With the advancement of robotic/automated systems (i.e. chain-climbing robotic mechanisms), interest in in-situ ultrasound inspection has increased. Currently, ultrasound inspection is confined to the weld area of the chain links. However, according to recent studies on fatigue and residual stresses, ultrasound inspection of the chain crown should be further investigated. A new automated application for ultrasonic phased-array full-matrix capture is discussed in this thesis for investigation of the chain crown. The concept of the chain-climbing robot and the inspection technique are validated with laboratory-based climbing experiments and presented in this thesis

    Laboratory Directed Research and Development Annual Report - Fiscal Year 2000

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    Maintenance Management of Wind Turbines

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    “Maintenance Management of Wind Turbines” considers the main concepts and the state-of-the-art, as well as advances and case studies on this topic. Maintenance is a critical variable in industry in order to reach competitiveness. It is the most important variable, together with operations, in the wind energy industry. Therefore, the correct management of corrective, predictive and preventive politics in any wind turbine is required. The content also considers original research works that focus on content that is complementary to other sub-disciplines, such as economics, finance, marketing, decision and risk analysis, engineering, etc., in the maintenance management of wind turbines. This book focuses on real case studies. These case studies concern topics such as failure detection and diagnosis, fault trees and subdisciplines (e.g., FMECA, FMEA, etc.) Most of them link these topics with financial, schedule, resources, downtimes, etc., in order to increase productivity, profitability, maintainability, reliability, safety, availability, and reduce costs and downtime, etc., in a wind turbine. Advances in mathematics, models, computational techniques, dynamic analysis, etc., are employed in analytics in maintenance management in this book. Finally, the book considers computational techniques, dynamic analysis, probabilistic methods, and mathematical optimization techniques that are expertly blended to support the analysis of multi-criteria decision-making problems with defined constraints and requirements

    Technology 2003: Conference Proceedings from the Fourth National Technology Transfer Conference and Exposition, Volume 1

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    Proceedings from symposia of the Technology 2003 Conference and Exposition, December 7-9, I993, Anaheim, CA. Volume 1 features the Plenary Session and the Plenary Workshop, plus papers presented in Advanced Manufacturing, Biotechnology/Medical Technology, Environmental Technology, Materials Science, and Power and Energy

    NASA thesaurus. Volume 1: Hierarchical Listing

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    There are over 17,000 postable terms and nearly 4,000 nonpostable terms approved for use in the NASA scientific and technical information system in the Hierarchical Listing of the NASA Thesaurus. The generic structure is presented for many terms. The broader term and narrower term relationships are shown in an indented fashion that illustrates the generic structure better than the more widely used BT and NT listings. Related terms are generously applied, thus enhancing the usefulness of the Hierarchical Listing. Greater access to the Hierarchical Listing may be achieved with the collateral use of Volume 2 - Access Vocabulary and Volume 3 - Definitions

    Proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress

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    Published proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress, hosted by York University, 27-30 May 2018

    Index to 1985 NASA Tech Briefs, volume 10, numbers 1-4

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    Short announcements of new technology derived from the R&D activities of NASA are presented. These briefs emphasize information considered likely to be transferrable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. This index for 1985 Tech Briefs contains abstracts and four indexes: subject, personal author, originating center, and Tech Brief Number. The following areas are covered: electronic components and circuits, electronic systems, physical sciences, materials, life sciences, mechanics, machinery, fabrication technology, and mathematics and information sciences

    Space station systems: A bibliography with indexes (supplement 10)

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    This bibliography lists 1,422 reports, articles, and other documents introduced into the NASA scientific and technical information system between July 1, 1989 and December 31, 1989. Its purpose is to provide helpful information to researchers, designers and managers engaged in Space Station technology development and mission design. Coverage includes documents that define major systems and subsystems related to structures and dynamic control, electronics and power supplies, propulsion, and payload integration. In addition, orbital construction methods, servicing and support requirements, procedures and operations, and missions for the current and future Space Station are included
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