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The Arctic Wave Glider on board the RV Ukpik. WAVE RADARS DIRECTIONAL WAVE AND CURRENT MONITORING SM-050 WAVE AND CURRENT RADAR, Microwave Doppler Radar of High Accuracy. WAVEX, Wave and Current Extractor for Marine Radars. Type Approved by DNV. Six RST Instruments Ltd. (Maple Ridge, Canada) Therm- Array thermistors were molded into the tether at depths of 0.5, 1, 1.5, 3, 4.5 and 6 meters, in addition to a standard satellite-based command and control, and data-handling package. Communication was through an RS-485 transceiv- er to the command and control electronics. Data were re- corded on board the AWG and transmitted in near real time at user-selectable intervals. A one-minute interval was cho- sen for this mission, which was oversampled but allowed researchers to evaluate sending large files through the Wave Glider platform. Uncertain solar power availability during late summer motivated the use of a supplemental lithium-ion battery pack of 1,200-watt-hour capacity. This module has the ca- pacity to provide backup power to the AWG system for 15 days of operation. Additionally, an aft-mounted camera connected to the Iridium Communications Inc. (McLean, Virginia) link was installed to send back real-time images for situational awareness because of the unknowns of working in the sea- sonal ice zone. Tests were conducted on the bench and in the field to determine the fatigue endurance of the AWG umbilical, increased drag due to the faired polyurethane overmold- ing, and the accuracy and response time of the thermistors. Early on in the development, a highly accelerated life test of one of the thermistor umbilicals was conducted by cycling a 720-pound load every 2.4 seconds for 30,000 cycles. Analysis showed that several thermistor wires failed under strain. While the test was ultimately judged to be too harsh, a subsequent modified design with unique strain relief loops was developed, deployed and tested at the Liquid Robot- ics marine engineering and test facility in Hawaii for three weeks and passed without incident. The AWG was raced against a baseline vehicle with an unmodified umbilical and was less than 0.1 knot slower on average, with no change in station-keeping ability. All thermistors were pre- and post-mission calibrated, and ac- curacies for all thermistors were less than 0.01° C after cali- bration factors were applied. Only one thermistor showed an appreciable drift of approximately 0.15° C at lower tem- peratures between calibrations; all others were less than 0.02° C. Thermal response tests were also conducted by plunging a complete umbilical from room temperature (20° C) to the controlled bath at –1° C. The thermal response time, which is defined as the sensor reading 63.2 percent of a steady-state temperature, was determined to be about nine minutes for all thermistors. DIRECTIONAL WAVE AND CURRENT RADARS ARE WELL SUITED FOR: Ɣ Offshore structures and vessels. Ɣ Catamarans and high speed vessels. Ɣ Naval and merchant vessels. Ɣ Research and service vessels. Ɣ Shore installations for ports and coastal stations. NON-DIRECTIONAL WAVE MONITORING, AIR GAP AND TIDE GAUGE SM-048 ALTIMETER AND SM-094 RANGE FINDER, High Performance Microwave Sensors. NON-DIRECTIONAL MIROS RANGE FINDERS FEATURE: Ɣ Wave profile and air gap from vessels and offshore structures. Ɣ Sea level and tide measurements, water level in ports and canals etc. Ɣ Bridge clearance monitoring. Ɣ 10, 20, 50 and 85 meter range. Ɣ No influence by fog, rain or water spray. OIL SPILL DETECTION OIL SPILL DETECTION BY X-BAND RADARS, A New System Based on Processing of Radar images. MAIN FEATURES: Ɣ Early detection of oil spills. Ɣ Enables 24 hours a day skimmer operations. Ɣ Prediction of oil spill drift. Ɣ Flexible user interface. Ɣ Add-on to the Wavex system, providing additional sea state information. AREAS OF USE: Ɣ Stand-by and oil recovery vessels participating in clean up operations. Ɣ Coast guard vessels for oil spill monitoring. Ɣ Oils rigs, FPSOs and tankers for oil spill monitoring. Ɣ Oil terminals and refineries for oil spill monitoring in the terminal area. Developed in cooperation with NOFO – Norwegian Clean Seas Association for Operating Companies Solbråveien 20, NO-1383 Asker, Norway Tel: +47 66 98 75 00, Fax: +47 66 90 41 70 E-mail: office@miros.no, Web Site: miros.no - measuring the ocean surface www.sea-technology.com SEPTEMBER 2012 / st 27