Sea Technology

FEB 2013

The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community

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Compass, Tilt, Acceleration, Gyro The fnal improvement made to the existing MMP to meet an OOI specifcation was the addition of Oceanserver Technology Inc.���s (Fall River, Massachusetts) OS5000 compass/ tilt/acceleration/gyro (CTAG). The small size of the OS5000 allowed McLane to add it to the secondary interface board. The data density���125 kilobytes per 500 meters of profle��� required the use of an additional fle for CTAG data. Since the start of motion is expected to be the most energetic section of the profle, the CTAG data are collected at 2 hertz during the two-minute stationary period and motor start-up at the beginning of the profle. Once the profler is at full speed, the data rate is decreased to 1 hertz. The CTAG data fle is stored on the fash card and can be transferred back to the Mission Planner like the sensor and engineering data fles or left on the fash card until recovery. Inductive modem test controller, electronics and inductive coils mounted on the seabed frame in transit to the test site. A battery-endurance estimate is made by the Deployment Planner to aid the user in managing the science requirements and maximizing the battery usage. Upon profler recovery, the Unpacker parses the binary data recovered from the fash card at the end of a deployment into delimited text for further processing. Normally, these tasks occur once per deployment per profler. However, this project requires a Mission Planner to process data retrieved during the deployment from multiple proflers. In addition to the integration of the Deployment Planner and Unpacker, the Mission Planner adds basic data display and a more accurate estimate of battery endurance. The data display module uses the parsed output format from the Unpacker to display engineering and sensor data over the available range in multiple formats: overlay, time line, scatter and 2D contour. Although not a full post-processor, the Mission Planner provides suffcient data display to determine the proper function and health of the profler and sensors. Moreover, the battery endurance estimator uses the same parsed data to calculate battery usage to date. Since the actual motor currents and profle times are available in the engineering fles, this estimate is more accurate than the predeployment estimate, which uses a constant nominal current drain for the motor and planned profle times. This data display and more accurate battery endurance estimate can be used to make scientifc decisions about needed schedule changes to examine a feature or adjust the profling frequency. Once the decision to change the mission is made, the user can create a new schedule and send it back to the deployed profler via satellite and inductive modem. After the profler applies this new schedule and begins executing it, the schedule will return to the Mission Planner with other new data and be displayed in the database tree to document the change. The cascading database tree provides a visual representation of missions, deployments and profles for easy reference during and after the missions. Underlying metadata uniquely specify the locations of the moorings, depths, sensor suite and active schedule. The integration of all profler engineering and sensor data into the Mission Planner provides additional insight into profler performance and allows the user to more easily compare multiple missions connected in time or by location. 18 st / FEBRUARY 2013 Sensors and Schedule During the development and testing of these proposed improvements to the existing profler, the science and engineering team at OOI chose the sensor suite for the Coastal and Global WFP. The Coastal WFP will have a Sea-Bird 52MP CTD with dissolved oxygen, a Nortek AS (Oslo, Norway) Aquadopp current meter, a WET Labs (Philomath, Oregon) BBFL2 optical sensor and a Biospherical Instruments Inc. (San Diego, California) QSP-2200. The Global WFP will have a Sea-Bird 52MP CTD, a Falmouth Scientifc (Cataumet, Massachusetts) ACM-Plus, an Aanderaa (Bergen, Norway) Optode 4330 and a WET Labs FLBBRTD optical sensor. Both Coastal and Global WFP will have Sea-Bird IMM inductive modems to match existing infrastructure. The critical design review was conducted in May 2012 and the frst article production began in June. The frst article units for both Coastal and Global WFP were completed in January. Optional production units are expected to be delivered through June 2013. Acknowledgments The authors will like to acknowledge the support of the engineers, staff and management at McLane Research Laboratories Inc. and Woods Hole Oceanographic Institution for their commitment and dedication to the success of the moored profler and the OOI WFP contract. They also appreciate the cooperation, support and engineering expertise that they received from the sensor manufacturers, especially Greg Johnson and Jerry Molnar from RBR Ltd. for their assistance prior to and during the inductive modem feld test. Funding for this contract came from the Consortium for Ocean Leadership, the management organization for the OOI. The OOI is funded by the National Science Foundation through a cooperative agreement with Ocean Leadership. OOI will construct a networked infrastructure of science-driven sensor systems to measure the physical, chemical, geological and biological variables in the ocean and seafoor. n Michael Mathewson is the general manager at McLane Research Laboratories Inc. He received a degree in mechanical engineering from Cornell University and a master���s degree from the University of Washington. Cleo Zani is the lead software engineer at McLane Research Laboratories Inc. and is responsible for development of embedded underwater data acquisition, control and instrumentation systems. www.sea-technology.com

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