The current GPS status and signal quality is indicated by different GPS icons in the status bar of the
operating software.
Before starting a scan, you should always look at the GPS icon and the indicated quality. If no GPS data
is available or position deviation is high, try to find a position with better signal quality.
A limited GPS signal can have many different causes. As with portable navigation devices, make sure
that the scanner always has an unobstructed view of the sky. Obstructions can block the signal reception,
causing position inaccuracy or no position data. The GPS signal can also be reflected by objects (for
example, buildings or mountains), causing the measured position to wander. The more satellites the
sensor has in view, the better the fix is.
Altimeter
The barometric height sensor (altimeter) determines the altitude of the current scanner position. The
altitude determination is based on the measurement of the atmospheric pressure. The measured altitude is
attached to each scan, and can be used for the scan registration in SCENE. See the SCENE user manual
for more information. If you want SCENE to automatically use the measured altitude for the scan
registration, switch the
Use Altimeter
to ON; else switch it to OFF. This setting affects the current
scanning parameters, and has the same function as the equivalent button in the parameters settings. See
Setting the Scanning Parameters
To see the currently measured altitude on this screen, the altimeter must be switched ON.
For scan registration, you need only know the difference in altitude of the various scanner positions.
Before starting your scan project, you should pick a position for your scanning site that you would like
to use as the reference for the altitude measurements. Move the scanner to this reference position, enter
any height you would like to use for this position, then reset the altimeter to this reference height by
tapping
Sync Reference Height
. All further altimeter measurements are then done based on this reference
height.
If you want comparable height measurements across different projects, sync the altimeter with a real
altitude. Pick a reference position of your scanning site, where you know the approximate altitude above
sea level. You can get this value from a GPS, topographic map, or from Google Earth.
Since the altimeter determines the altitude based on the atmospheric pressure measurement, changes in air
pressure caused by changing weather conditions effect the resulting altitude. To get precise altitude
measurements, periodically check the reference altitude; at least at the beginning of each project day and
when the weather changes. To do this, move the scanner back to your reference position, and compare
the altitude reading with the reference height. If there is a difference, re-sync the altimeter with the
reference height.
FARO
®
Focus Premium Laser Scanner User Manual
Chapter 6: Controller Software
FARO Focus Premium (March 2022)
Page 85 of 157
