Intel Falcon 8+ User Manual page 68

position in GPS-Mode, immediately activate Height-Mode. Be prepared that
you now need to control the position manually on the CTR.
Figure 3-11. GPS accuracy
The GPS module of the Intel Falcon 8+ UAV supports GPS and GLONASS. Under ideal
conditions, the horizontal accuracy can reach around +/- 2 m. The short-term
accuracy is usually higher, because of the data fusion with other available sensor
output from the IMU. Vertical accuracy of GPS is lower and the measured altitude can
vary up to 15 m depending on satellite constellation. A barometric measurement is
used for altitude instead of relying on GPS. Height is always measured above ground
level and is reset to zero when the rotors are being started. Throughout the duration
of a mission there can be a drift of +/- 5 m due to all possible errors: temperature,
drift, weather changes, etc.
Figure 3-12. Shadowing
The position accuracy can be impaired when obstacles block the direct line-of-sight
from many satellites. The obstacle virtually casts a GNSS-shadow over the concerned
area. This results in fewer received satellite signals and a changed geometry of the
signals themselves. This effect is very common e.g. in urban areas, where satellites can
be blocked by tall buildings. It may occur that along one side of the street the position
68
IMPORTANT
The GPS receiver module of the Intel Falcon 8+
UAV is placed directly underneath the canopy of
the central unit and is surrounded by an
antenna. The canopy of the Intel Falcon 8+ UAV
is made from a material which does not
influence the satellite signals, but anything on
the top of the Intel Falcon 8+ UAV can
potentially disturb the signal. Never cover the
GPS receiver module nor the antenna area to
ensure best possible GPS reception.
User Manual ®
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Intel Falcon F8+