External barometric pressure sensor

[kitercuda]

Čekáme na 3D tiskárnu, aby se dalky vyrobit krabičky...

[Sheba]

Hello, it's me again

The current external baro seems to work more or less OK (I didn't try it myself in the air, my fellow colleagues told me that they were experiencing some drops in the communication inflight, but it could also be a HW issue). On the other hand, the current external baro sensor that is supported is quite limited in its usefulness, as it only sends the pressure to the software.

Last year, we have started using in our club the Open Glider Network (which works just as well also for GA and UL aviation), which is a position-tracking network of ground based receivers and airborne transmitters - either commercial Flarm devices, or cheap homemade OGN trackers. These OGN trackers can be easily equipped with a BT module and a barometric sensor, and can provide to the flight navigation apps the GPS position, pressure and also collision warning (when it detects another OGN tracker or a Flarm on a collision course). The OGN system is getting quite popular across the whole Europe, as it offers a lot of functions and improvea the safety of air traffic. The total cost of one OGN tracker is less than 60€ (depending on the used parts), more details can be found here or here (CZ only).

The data coming from the OGN tracker looks like this, the sentence POGNB contains the pressure info and the PFLAU sentence contains the collision warning level. Would you be interested in the implementation of this protocol into your app? I can once again send you one tracker for testing, I have some spare ones used for testing

Code: Select all

$POGNT,33,1,3,03AF2A,0,21,2.7,4914.9412N,01634.9528E,264,,+0.2,0.1,000.0,+0.0,-30,0*15
$PFLAA,0,+24,+46,-3,3,03AF2A,000.0,+0.0,0.1,+0.2,1*2A
$POGNB,35.0,+18.6,97992.5,0.9,+281.2,+291.0,-0.06,*40
$PGRMZ,+281.2,m,3*2C
$GPRMC,195235.00,A,4914.92811,N,01634.91502,E,0.036,,060917,,,A*71
$PFLAU,0,1,1,1,0,,0,,*63
$GPGGA,195235.00,4914.92811,N,01634.91502,E,1,06,1.35,268.1,M,42.4,M,,*5F
$GPGSA,A,3,07,23,02,06,30,05,,,,,,,3.29,1.35,3.01*0B
$POGNR,1,4,0,-111.0,7,+23,+32.4,3.23*42
$POGNB,35.5,+18.6,97993.3,0.9,+281.1,+290.9,-0.06,*49
$PGRMZ,+281.1,m,3*2F

[Tonio]

Hello
Integrating traffic detection within FIF is great idea and OGN seem interesting, but question:
Anticipating that very soon transponder and probably to ADSB-Out could become mandatory for general aviation and ultralight (that wish entering controlled airspace) what is the advantage of your solution? knowing that ADSB-In receptor is affordable

[Sheba]

Hi,
there is actually only a small difference in the technical solution, mostly just the frequency, transmission power and the amount of transmitted data. The main difference from the user point of view is the price and availability (the OGN trackers are way cheaper than the transponders and can be built by anyone), as well as the existing network of receivers (good for both solutions) and transmitters (I'd say there are way more Flarms/OGN trackers than GA/ULL planes with ADSB). I only have experience with OGN, so that's what I'm offering

[Sheba]

Hi,

as there was no feedback on my previous idea regarding OGN trackers, I helped myself the other way around - I managed to adjust the OGN firmware to send baro messages that would be accepted by FiF. Unfortunately FiF is at least for now ignoring all the other interesting things in the bluetooth feed, such as GPS and collision data, but at least the baro is working fine.

The OGN tracker is well described here http://wiki.glidernet.org/ogn-tracker-diy, just build it using the RFM69HW RF chip, BMP280 baro sensor and use my attached firmware.