REMUS 100 Sea Trial Confirms CAT 1B Hydrographic Survey Capability

IHO Order 1 surveys by the Royal Australian Navy

New Generation Hydroid REMUS 100 Autonomous Underwater Vehicles have completed sea trials at Cape Cod Bay, Massachusetts, confirming a significant new capability for IHO Order 1 survey that will soon be operated by the Royal Australian Navy.

The evaluation was conducted and analysed by Seahorse Geomatics.  Reference surface data was first collected to provide baseline data for comparison with REMUS survey data. The baseline data was collected using a Norbit iWBMSh-STX which was mobilised aboard a vessel of opportunity. The survey in Cape Cod Bay was more than 60 km from the nearest NOAA tide station in Boston, MA. To compare the 3D Ellipsoidal Referenced Survey (ERS) reference surface with the unmanned underwater vehicle (UUV), a NOAA zoned tide definition file (ZDF) was used and applied for comparison to the PPK navigation solution as the ZDF with Boston tide station was required to be applied to the REMUS with pressure sensor information to vertically locate the vehicle.

Three validation checks were made to confirm the ERS derived reference surface was a valid surface to test the NOAA zoned tide REMUS data against:

• RTK positioned plate check compared to PPK derived (ERS) sounding data
• Applied ZDF surface comparison to PPK- ERS derived surface
• Comparison of both to a 2007 NOAA survey that overlapped the northeast portion of the survey area.

Prior to the REMUS survey, a patch test was run. During this survey, two sets of lines were collected in the same area. The first survey had a line spacing of 45 meters, and the second survey had a line spacing of 25 meters. For all surveys conducted, Navlab was used to collect post-processed navigation and motion data.

The completed REMUS 100 survey data, which included Navlab data, showed that the REMUS AUV had the capability to meet IHO Order 1 within both the vertical and the horizontal thresholds set by S-44. BlueZone GM, Andrew Hazell, said thanked Hydroid and Seahorse Geomatics for their support during the REMUS sea trials, “The sea trials have proven a significant new capability for the RAN,” said Andrew, “and BlueZone looks forward to supporting introduction to service of the New Generation REMUS 100 vehicles.”