Offsets & Reference Points
For quality, repeatable bathymetric data, the offsets between the sonar, attitude and positioning
sensors on the survey platform must be fixed and well known. The 3 axes should be accurately
aligned with the survey platform, or any angular misalignments should be measured and applied to
the acquisition/processing software.
Each sensor has predefined measurements between the WBMS Reference Point (sonar acoustic
center) and the IMU Reference Point, the WBMS Reference Point and the Top Center of Bracket,
and the IMU mounting angles. The relevant offsets and misalignments are applied automatically in
the WBMS GUI, so the user does not have to input them. The only case where the user must know
these values is if a custom installation is used, or if the Applanix firmware is older than 9.03 and all
offsets are entered manually in POSView.
By default, all data output from the integrated systems (position, attitude and depth information) is
valid at the WBMS Reference Point. Thus, all sensors in the acquisition and processing software
must have the same offset to this location. The offsets for each sonar are detailed in the next section.
Note that Top Center of Bracket is merely a convenient point from which to measure other sensors;
however, no data output is valid at this location.
CAUTION: Upgrade Applanix Firmware for NORBIT 10.4
For iWBMS, iWBMSh and iWBMSe, the integrated Applanix must have at
least 9.03 firmware. This enables the NORBIT GUI to take control of the
system and automate many of the setup parameters. Users of older firmware
versions are encouraged to contact NORBIT Support for upgrading.
To Next Page
Loading...
