Processing and management techniques for multibeam data

1. Processing and management techniques for multibeam data Fredericton – Canada Heeswijk – The Netherlands Ellicott City – United States Speaker: P Lund, July 2004

2. Data processing and quality control How HIPS interacts • HIPS BASE surfaces can be opened directly in BSE and submitted to the Bathy Database • Soundings designated in HIPS will migrate through to Bathy Surface Editor products • HIPS session files can be opened in for Notebook to assist in object validation

3. TPE is calculated by defining sensor error estimates in the Vessel Editor. Nav, Gyro, HPR, Tide, SVP - From manufacturers spec initially Latency errors Offset measurement error Specific MBES errors - from UNH HIPS 5.4Computing error budgets for TPE computation • Errors are used to compute DpTPE and HzTPE attributes for every sounding • These attributes are used to create BASE surface

4. TPE attributes are used to weight soundings in surface creation BASE is optimized for safety of navigation, shoals are retained MBES resolution is retained “CHILD layers” assist with data cleaning (focus on problem area) HIPS 5.4Benefits of BASE surfaces DEPTH DENSITY UNCERTAINTY St. DEV • Filter data to IHO S-44 standards • Auto or Manual designate golden soundings!

5. Fly-thru 3-D landscape Launch subset editor from 3-D mode to check suspect soundings Compare bathymetry features with sidescan in 2-D or 3-D Analyze surface profiles to determine features or artifacts HIPS 5.4Quality Control

6. Data management and bathymetric product creation How BSE/Bathy Database interact • BSE is the desktop client application of the Bathy database server • Bathymetric Products created here can be used in Chart production software e.g. HPD • Sounding and Contour objects created in BSE can be taken in Notebook

7. Bathy Surface DatabaseData Management PRODUCT FULL • Manage surfaces not full density sounding data • Workflow tracking and attribution through metadata • Browse raster thumbnails in database chart instead of full resolution surfaces • Import data of different densities either from HIPS BASE or 3rd party formats, GSF, CRS, MDF, XYZ…. • Combine surfaces from different sources into single seamless surface by defining supercede rules • Incorporate background samples for dataset orientation SURFACE

8. Radius = 1/100th of chart scale Rolling Ball Generalized Product Surface Finalized node resolution BASE surface Bathy Surface EditorProduct Surface Creation • Remove longest edges from sparse TINS • Densify sparse TINS into GRID surfaces • Smooth surface not contours, this can be a 1 or 2 stage process • Stage 1 = 3-D double buffering (MANDATORY) • Stage 2 = Surface defocusing (OPTIONAL)

9. Scale 1:10000 Bathy Surface EditorBathymetric Product Creation • Designated soundings retained after generalization to chart scale

10. Data management and bathymetric product creation How Notebook interacts • Bathymetric products created in HIPS and BSE can be opened in Notebook • Source bathymetry in HIPS can be spawned by querying selected soundings in Notebook • In field object observations can be passed to HPD or other charting software

11. Verify data in the field to avoid costly re-surveying Digital alternative to hardcopy field notes Attach Multimedia data to objects NotebookObject validation Add object names Add marker text • Export updates for hydrographic products faster by transferring to cartographers in S-57 format

12. Use BASE surfaces and mosaics from HIPS as reference data Supports S-57 ENCs, CARIS Maps, BSBs, GeoTIFFs, DGN and SHP Add new S-57 point, line, area and sounding features with attributes Add marker notes to assist cartographers Manipulate S-57 ENC content using sophisticated filter system Export updates to be included in chart production, *.000, HOB, *.des, and ASCII NotebookOther functionality