Thales Navigation Mobile Mapper - Manual (Page 24)

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9. Logging GIS Data on a Preset Grid Network
MobileMapper's grid mapping utility is an easy way to
automatically set up a series of GPS waypoints to facili-
tate the logging of data in an orthogonal grid. This utility
assures that you gather measurements made using field
sensors such as chemical detectors, depth sounders and
magnetometers at an evenly distributed set of locations.
This in turn assures the creation in your GIS of contour
maps with a prescribed density of data and without any
gaps that might force you to return to the field.
To log GIS data on a preset grid, do the following:
- Navigate to the waypoint of the grid where you
want to begin logging data: If you have created a
waypoint to help you locate the first grid point, you
can use any of MobileMapper's navigation screens to
get there. To access a waypoint file you can use to
navigate to the point of beginning, press the MENU
button and select the GOTO option. Then select the
User option. This will place the waypoint symbol and
label on the base map displayed on the receiver's Map
screen. Again, you may use any of MobileMapper's
navigation screens to arrive at this waypoint.
- Display the grid: Once you arrive at the point of
beginning, you should open up the job file that
includes the feature library describing the grid. If you
opened an existing job, press LOG to take you to the
New Feature screen. Then select the grid feature type
listed on the screen. Usually the term “grid” is
included somewhere in the feature name so that you
can easily recognize this type of feature. After select-
ing the grid feature, the Grid Setup screen appears on
which you can read the definition of the grid (spac-
ing, columns, rows and heading).
To operate the grid map-
ping utility, you will need
a measurement device -
anything from a depth
sounder to a ruler, your
own sense of smell or
your ability to make
visual observations. You
will also need a compass.
How a grid is defined in
MobileMapper
Heading
North
Column
Row
Spacing