Collaborative Research: Design, Modeling and Testing of Electro-Optic Mechanical [EOM] Mooring Cables for Moored-Buoy Observations

Woods Hole Oceanographic Institution, Woods Hole MA

Investigators

Abstract

P.I. Frye (WHOI) Proposal #: 0337893 Collaborating Inst: Chaffey (MBARI) Proposal #: 0337888 Proposal Title: Collaborative Research: Design, Modeling, and Testing of Electro-Optic Mechanical (EOM) Mooring Cables for Moored-Buoy Observatories Project Summary This proposal is for the development and testing of an electro-optical-mechanical (EOM) mooring system for use with the global network of moored buoy observatories. This EOM mooring cable and its related mechanical and electro-optical components is a crucial technological element of moored buoy observatories that at present is not well defined and is not available from commercial manufacturers. The goal of the proposed work is to develop a reliable and cost effective design for this key mooring component and the related termination and connection hardware. It will be applicable to most of the global network sites and reliable for periods of three to five years before replacement or repair. Existing EOM mooring/cable designs are expensive, unreliable and not designed for the full range of environmental conditions. In addition, reliable and tested methods for terminating the cables, connecting them to buoys and anchors and adjusting their buoyancy to meet the mooring configuration requirements are not available. The PIs propose to develop and test a complete and integrated mooring system for long term observatory applications that will provide the capability for real-time data and power transfer between surface buoys and submerged instruments arrays. The technical effort will include tasks to: 1) design and perform numerical modeling of candidate mooring configurations for moored buoy observatories, 2) develop laboratory test procedures that reliably predict cable and termination performance in the field, 3) design EOM cables, terminations, and strain- relief connection devices, 4) conduct laboratory strength, bending and fatigue testing of cable specimens, 5) develop techniques for predicting fatigue failure in synthetic EOM cables, 6) fabricate and field test a prototype EOM cable and mooring system, 7) instrument the mooring to collect engineering data on cable strain and bending to assess mooring and cable performance, and 8) perform post-deployment testing of mooring components to determine residual strength and compare these results to predictions of the fatigue models.