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Operation
SeaBat Sonar UI - User Manual
Figure 4-74
Checkboxes for enable/disable pipe detection and tracking.
4.10.1 Survey Settings
Set the speed of the vessel to aid the along track distance estimation.
(Can now be calculated.) This improves the pipe detection algorithm.
4.10.2 Pipe in Sway Detections
Figure 4-75
Pipe in sway detections parameters
The detections in a sway are done in a pipe window that goes from beam
to beam through the sway data. The pipe window is a window with the
width of the pipe diameter plus a margin that is placed over the ping to
find the best detection.
With the pipe detection parameters, beams will be discarded as noise and
from the beams in the sway that are not discarded the best detection will
become the pipe detection in the sway.
4.10.2.1 Pipe detect diameter
The diameter of the pipe that has to be detected.
If more pipes have to be detected it is better to enter the pipe diameter of
the biggest pipe to be sure that this pipe can be detected. When the other
pipe is 10-20% smaller it will still be detected.
4.10.2.2 Maximum free span filter
Detections that are higher than the
‘Maximum Free Span Filter’ above the
seafloor are discarded as noise.
4.10.2.3 Detection threshold filter
Detections that are lower than the
‘Detected threshold filter’ above the
seafloor are discarded as noise.
With an irregular seafloor and a small
‘Detected threshold filter’ more
detections will be found that have no relation to a pipe route, but it also
can result in that more detections are found on the pipe.
With a good value for the ‘Detected threshold filter’ almost all the
detections are on the pipe.
When the value becomes too small also a lot of detections are found that
are not on the pipe. This can result in that also pipe parts are found that
actually are not pipes.
4.10.2.4 Statistic threshold filter
In the pipe window a mean Z is calculated with a standard deviation.
For each beam a
ΔZ (= Mean Z – Beam Z) is calculated. The beams in
the pipe window with a smaller
ΔZ than the ‘Statistic threshold filter’ *
‘Standard Deviation Pipe Window’ are discarded as noise.
