ATOM UAV MANUAL
Date: 2021-09-30
Version: 0.8
Page: 8 of 20
FLARM Technology Ltd
Hinterbergstrasse 15
CH-6330 Cham
Document Number:
FTD-088
With “MAV_1_FORWARD: 1”, Atom UAVs Heartbeat will be forwarded to the
Ground Control Station and can be seen in its MAVlink Inspector with the
component id 160.
2.1.2
Using Navigation Solution from PX4
Instead of using the integrated GNSS module for positioning, Atom UAV can use
the navigation solution from PX4. This requires installing an EXG license on Atom
(see Sections 3.2 and 3.4). If EXG is installed, Atom uses the Navigation solution
from Mavlink instead of that from the own GNSS module. For this, it consumes the
GPS_RAW_INT and SYSTEM_TIME messages and issues the TIMESYNC message
for time synchronization. Because the Flarm RF protocol is very time-sensitive, the
provided mavlink time needs to be accurate. To reduce jitter, a Mavlink mode like
OSD that emits SYSTEM_TIME and GPS_RAW_INT, but as few as possible other
messages should be used. A static time offset will be configurable to compensate
for systematic latency.The methodology will be described in detail once available.
2.1.3
Compatible GCS Software
GCS software which supports display of ADSB_VEHICLE packets:
QGroundControl (verified on v4.1.1)
Other GCS may offer support, too.
2.2
JSON
A JSON message stream providing a user friendly to interface with Atom UAV is
available on the JST port. A detailed interface description can be found in document
FTD-092.
The protocol sends out unsolicited heartbeat and traffic information. Furthermore,
currently a simple JSON command is used to encapusalte NMEA configuration
sentences to enforce the flight state.
