Sensors & Software LMX100, Руководство пользователя

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Data Collection
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6.1.2 Back-Up Indicator
Data collection mode incorporates a back-up feature to enable you to accurately locate targets
and mark them on the ground. After acquiring some data on the screen, pull the system
backwards (Figure 6-3a).
During back-up mode, there will be two indicators:
•
Position Indicator : The red vertical line corresponds to the location at the center of
the GPR sensor. As you pull the cart backwards, the Position Indicator moves to
mark the current location of the cart in the image and a box appears at the bottom of
the screen with the current position, relative to the start of the line, listed as the top
number.
•
Depth Indicator : A short red horizontal line corresponds to the current depth value,
as shown in the lower number in the box at the bottom of the screen. To determine
the depth of an object, move the indicator up or down by dragging the horizontal line
to the desired location (Figure 6-3b). Alternatively, you can also use the
Up and
Down arrows on the 4-way directional keypad. Note: make sure you have done a
Soil Calibration to ensure depth accuracy ( Section 6.2.4).
Figure 6-3: a) Back-up Indicator, b) Moving the Depth Indicator to the top of the hyperbola
To locate a feature, simply roll the system back along the same path until the red vertical line is
exactly over the response (usually a hyperbola). You can mark the location of the object on the
surface and continue data collection. Once you reach the point where you initially started backing-
up, the system will continue acquiring new data.
You can also obtain depth and position information anywhere on the Line Scan by touching the
screen, holding for a second, then releasing. A cross-hair appears where you touched the screen,
with a box displaying the position and depth (Figure 6-4). To get the position and depth
information about a different point on the screen, simply drag the box or cross-hair to the desired
position.