Utsira Nord Floating Wind farm – Optimalisation of marine operations related to inter-array cable installation.

The offshore wind industry is experiencing significant growth, with wind farms expanding in size, capacity, and moving to more challenging locations. However, cable faults remain a major concern, particularly during the installation of inter-array and export cables. This thesis aims to research and analyse the installation steps of inter-array cables at the Utsira Nord offshore wind farm. It further seeks to enhance the installation process by identifying functional sea states through a combination of previous work and new data. The research focuses on answering key questions related to the installation of inter-array cables. This includes identifying the main steps, defining critical phases, and analysing the typical loads that impact cable installation to determine the parameters affecting the process. Additionally, the thesis seeks to determine the optimal environmental conditions for cable installation. The methodology employed in this thesis includes literature studies, experience from employees at DeepOcean regarding offshore operations, and the use of Orcaflex and Excel. The analysis, primarily conducted using Orcaflex, concentrates on the installation of 1st and 2nd end dynamic section. The floating windmill is treated as a fixed structure in the Orcaflex model, neglecting its movement due to the ongoing development of the foundation concept and limited comprehensive information on weather and environmental factors. The study primarily focuses on tension and curvature acting on the cable during installation, disregarding boat and floating structure considerations that are not directly relevant to the research objectives. From the knowledge gained in the literature review, an analysis was carried out to investigate crucial parameters in the cable laying process and a conclusion for when it is optimal to do inter-array cable installation operations at Utsira Nord was given. The focus was on tension loads, minimum bending radius, and potential clashes with the Moonpool. This was conducted with both Gumbel and Rayleigh analysis with irregular vessel motions. The result of the analysis illustrated the extent of impact the various environmental wave conditions had on the system. Throughout the study, certain wave conditions were found to be more favourable than others. Wave directions ranging from 90-135° and 225-270°, simulated with a current velocity of 0.3 m/s, offered the most optimal conditions for cable installation. In contrast, the analysis showed that sea states with wave directions of 0° and 180°, as well as current at 1.0 m/s, presented a higher risk of cable damage. To enhance the findings of this master's thesis, further analysis of different current velocities is recommended to identify operable sea states under higher currents. Additionally, analysing the system with a moving floating wind turbine, given that sufficient data is available

Cumulative index to NASA Tech Briefs, 1963-1967

Cumulative index to NASA survey on technology utilization of aerospace research outpu

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 42)

Abstracts are provided for 174 patents and patent applications entered into the NASA scientific and technical information system during the period July 1992 through December 1992. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

Mu2e Technical Design Report

The Mu2e experiment at Fermilab will search for charged lepton flavor violation via the coherent conversion process mu- N --> e- N with a sensitivity approximately four orders of magnitude better than the current world's best limits for this process. The experiment's sensitivity offers discovery potential over a wide array of new physics models and probes mass scales well beyond the reach of the LHC. We describe herein the preliminary design of the proposed Mu2e experiment. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-2 approval.Comment: compressed file, 888 pages, 621 figures, 126 tables; full resolution available at http://mu2e.fnal.gov; corrected typo in background summary, Table 3.

Cable-driven parallel mechanisms for minimally invasive robotic surgery

Minimally invasive surgery (MIS) has revolutionised surgery by providing faster recovery times, less post-operative complications, improved cosmesis and reduced pain for the patient. Surgical robotics are used to further decrease the invasiveness of procedures, by using yet smaller and fewer incisions or using natural orifices as entry point. However, many robotic systems still suffer from technical challenges such as sufficient instrument dexterity and payloads, leading to limited adoption in clinical practice. Cable-driven parallel mechanisms (CDPMs) have unique properties, which can be used to overcome existing challenges in surgical robotics. These beneficial properties include high end-effector payloads, efficient force transmission and a large configurable instrument workspace. However, the use of CDPMs in MIS is largely unexplored. This research presents the first structured exploration of CDPMs for MIS and demonstrates the potential of this type of mechanism through the development of multiple prototypes: the ESD CYCLOPS, CDAQS, SIMPLE, neuroCYCLOPS and microCYCLOPS. One key challenge for MIS is the access method used to introduce CDPMs into the body. Three different access methods are presented by the prototypes. By focusing on the minimally invasive access method in which CDPMs are introduced into the body, the thesis provides a framework, which can be used by researchers, engineers and clinicians to identify future opportunities of CDPMs in MIS. Additionally, through user studies and pre-clinical studies, these prototypes demonstrate that this type of mechanism has several key advantages for surgical applications in which haptic feedback, safe automation or a high payload are required. These advantages, combined with the different access methods, demonstrate that CDPMs can have a key role in the advancement of MIS technology.Open Acces

Proceedings of a Workshop on Applications of Tethers in Space: Executive Summary

The workshop was attended by persons from government, industry, and academic institutions to discuss the rapidly evolving area of tether applications in space. Many new applications were presented at the workshop, and existing applications were revised, refined, and prioritized as to which applications should be implemented and when. The workshop concluded with summaries developed individually and jointly by each of the applications panels

Development of Power Assist Crane Operated by Tensional Information of Dual Wire

Cranes and hoists at automotive assembly plant handle heavy objects such as batteries to decrease the physical burden on personnel. On/off button operations in such devices during fine positioning increase personnel mental stress. On the other hand, in power assist using force sensors which directly measure operating force, maneuverability is improved but we should be concerned about sensor weight, signal wiring, wire breakage and so on, so in this study, a power assist system driven by two wires is developed to improve maneuverability and maintenance. The method we propose estimates operating force and work load from tension information on wires and controls the position of work by admittance control. The effectiveness of the proposed method is shown from confirmation and power assist experiments