User's Manual

Smart Systems User’s Manual Version 1.1
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Hyperbola Matching calibration can only be done during data acquisition. It cannot be
done when viewing previously collected data. Further, the Hyperbola Matching
calibration is only available after at least half a screen of data with the same depth
setting have been collected. If less than half a screen of data are collected and the
CALIB button is selected, only calibrations selecting a material or inputting a
velocity are available (see below).
Depths will appear in metres or feet depending on which units are selected. Velocities
appear in both metres per nanosecond (m/ns) and feet per nanosecond (ft/ns). To
change units see Section 5.5.1 - Units.
Target of Known Depth
If there are no suitable hyperbolas visible in the data to perform the Hyperbola Matching
described above, it may be the situation that there is a target of known depth in the area
being scanned. If this is the case, selecting the button with the circle with a horizontal
line through it will superimpose a horizontal line on the data. This line can then be
moved up or down until it lies on top of the Noggin response to the known target. Then,
the user can adjust the velocity value up or down until the known target depth is correct.
Once the depth is matched, the current velocity value is the one used for all subsequent
data acquisition.
(a) (b)
Figure 5-6: Using a target of known depth to extract velocity. After selecting CALIB, choosing the
known depth button (a circle with a horizontal line through it) will superimpose a horizontal line on
the data (a). Using the depth buttons, this line can then be moved up or down until it lies on top of
the Noggin response to the known target (b). Then, the user can adjust the velocity value up or
down until the known target depth is correct. Once the depth is matched, the extracted velocity
value is automatically used for all subsequent data acquisition.