Spectra Precision Survey Pro v4.6 Ranger User Manual - Manual (Page 159)

Other Conventional Surveying Tutorials
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Localizing
With your backsight set, the data collector now knows your position
in the job’s coordinate system and since it is receiving a GPS signal,
the data collector also knows your position in the geodetic coordinate
system, but the data collector has not yet aligned the job’s coordinate
system with the geodetic coordinate system. This is indicated by a
yellow satellite icon with a question mark in the Command Bar.
The process of aligning the two coordinate systems is called localizing
and until that happens; you will be unable to use the GeoLock
feature, although you can still collect data.
Localizing takes place automatically in the background as you move
around as long as the EDM is set to Track because the total station is
routinely measuring your location while the GPS receiver is
simultaneously measuring your location. Both of these
measurements are compared and in theory, the more comparisons
from different locations that are made, the better your localization
and GeoLock solution will be. Once a localization solution is
available, the satellite icon will change to green .
Localization will still occur if the EDM is set to Standard, but a
solution will take much longer to obtain because the total station will
only measure your location when you take a shot.
There may be some situations where you will want to throw out your
localization solution and start over. For example, if you moved the
GPS receiver away from the prism, the GPS position would no longer
match the position measured by the total station, resulting in an
incorrect localization solution. To reset your localization, tap the
satellite icon and select Reset from the list. The icon will change
back to yellow and you will need to move around again to re-
localize before you can use the GeoLock feature.
Using GeoLock
If you have a localization solution and the total station loses lock on
the prism, the GeoLock button will be enabled. Tapping it will
instruct the total station to turn to the location of the prism based on
the last GPS reading, followed by a search until the total station is
locked back onto the prism.