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Track: Oceanography, Coastal Zone, Marine Resources
Gerry Hatcher
Monterey Bay Aquarium Research Institute (MBARI)
PO Box 628
Moss Landing, CA 95039-0628
Telephone: 408-775-1758
Fax: 408-775-1620
E-mail: gerry@embari.org
Norman Maher, Daniel Orange
The Customization of ArcView as a Real-Time Tool for Oceanographic Research
Defining Issue: - Oceanographic data sets are of uneven distribution, quality, resolutions, and size. - New data collected during a cruise often need to be used to make informed decisions while at sea. - Operating conditions usually consist of very limited visibility and a poor frame of reference. - Hours of video data can be collected that are difficult to review and are not easily georeferenced. - Trips to sea aboard ships can have operational costs in excess of $20,000 per day. GIS Solution: A GIS is highly suited to oceanographic applications for several reasons: (1) most oceanographic data are digital and are therefore suited for computer analysis with a GIS, (2) oceanographic data sets have uneven distribution with widely varying scales and quality, and a GIS can efficiently handle these problems, and (3) data are easily incorporated into ArcView GIS, which allows data to be checked for consistency and accuracy during the collection process and not months later. A customization of ArcView has been
created at Monterey Bay Aquarium Research Institute (MBARI) for use as a real-time tool during oceanographic research cruises. The customization uses real-time data to continuously update the position and orientation of scaled graphic objects that indicate the true position and heading of any number of vehicles and their relation to oceanographic data sets. This provides a consistent frame of reference that enables the oceanographer to locate (and return to) sites of interest cost effectively. For example, icons representing the actual altitude and locations of a surface ship and a Remotely Operated Vehicle (ROV) are displayed on top of data layers such as raster nautical charts, bathymetric contour coverage, sonar data, and the previous day's dive tracks. This allows the user to navigate efficiently and accurately using "point and click" methods rather than with paper charts and notebooks in a darkened control room on a rolling ship. Specialized software tools for real-time operations were created such
as a "digital notebook" for recording geographically referenced user comments, a tool for capturing geographically referenced video stills from a remotely operated vehicle, and several others. While at sea, newly collected data sets are processed using ArcInfo on a UNIX workstation and then quickly incorporated into the real-time GIS for immediate use. Methodology: This system has been deployed on three different ships in the last 12 months with three different ROVs in different parts of the world. The setup has been similar in all cases and consists of a data acquisition computer that reads navigation and attitude information from the vehicle sensors. These data are then distributed via the ship's network to any number of ArcView "clients." The ArcView "client" uses a DLL software extension to read the data from the network and continually update its graphics. The data are then available for other Avenue programs in the customization such as the "digital notebook." The capture of georeferenced video
stills is done also using a DLL extension to ArcView, which communicates with a Snappy(TM) video frame grabber. For at-sea data processing, ArcInfo on an HP workstation is used. The other ArcView navigation tools are written in Avenue and the GUI has been customized for their use. Software: This application uses ArcView, Avenue, ArcInfo, AML, and Microsoft Visual C++.
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