OGN Tracker implementation on ESP32 devices or anything which can be handled with platformio
It works on TTGO modules like various T-Beam modules including the ESP32-S3 version.
Use Chrome/Edge: https://pjalocha.github.io/ogn-tracker/
This project is open-source and developed in my spare time. If you find it useful, please support development and research related to the Open Glider Network:
- OGN/ADS-L/FANET trackers
- OGN ground receivers which form the base of the network
- Stratux project: the OGN part
- testing sotware and hardware, experimentation needed to improve things
Donate via PayPal: https://paypal.me/paweljalocha
to run an OGN-Tracker you need to have at least:
- CPU: most common ESP32 -S3 -C3
- ISM radio tranceiver: SX1276 or SX1262
- GPS receiver: u-Blox or other
Optionally, you can add
- Pressure sensor: most common BMP280
- display: OLED or LCD
The most popular is likely TTGO T-Beam: there are several variants with different radio chips and charge/power controllers There are some ready-to-use devices like ThinkNode-M5 which can be simply bought, programmed and there you have an OGN-Tracker ready which is visible to electronic conspicuity receivers. Programming can be done directly from the web page using the embedded ESP32 programmer: https://pjalocha.github.io/ogn-tracker/
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The ROOK case shown above fits very well the HTIT-Tracker from Heltec and offers another path to get a working OGN-Tracker. Compared to ready-to-use devices, this option requires a bit more work: you need to get the case/parts, the battery, make the required connections and put everything together.
often ignored but they are essential for proper function of the tracker and not just the antennas themselves but where and how are the antennas installed:
- GPS antenna: should see good part of the sky for stable and accurate position acquisition
- ISM antenna: should not be screened by metal and/or carbon fibre sheets for stable and strong radio signal and reception/relay of other trackers
The primary signal transmitted is the OGN-Tracker specific packet and position protocol. Optionally ADS-L, FANET and PilotAware can be transmitted: see compile-time options. As the electronic conspicuity is now going towards ADS-L the three ADS-L modulations: MDR, LDR and HDR are gaining importance.
Reception and visualization is possible: the data is being sent via BT and can be seen with applications like XCsoar
There is an experimental algorithm running on the device which can produce warning beeps and markes the aircrafts of concern for the visualization app
You will need platformio which takes care for getting the right compiler and upload tools
is done through the profiles defined in platformio.ini - to choose the right code use -e option of the pio command.
To check all defined profiles inspect the platformio.ini file or type:
grep env platformio.ini
You only need the command-line part which can be quickly installed on Ubuntu
Note: DO NOT install platformio with sudo apt-get install platformio and if you did then remove it
Type:
sudo apt-get install python3.10-venv -y
sudo apt install curl -y
curl -fsSL -o get-platformio.py https://raw.githubusercontent.com/platformio/platformio-core-installer/master/get-platformio.py
python3 get-platformio.py
Type: pio --version command, if not working then try ~/.platformio/penv/bin/pio --version
To upload code to a T-Beam v1.0 module with SX1276 RF chip connected on the /dev/ttyACM0 USB-serial port type:
pio run -e ttgo-sx1276-tbeam-v10 -t upload --upload-port=/dev/ttyACM0 && minicom -D /dev/ttyACM0
After a succesful upload the above command starts minicom so you can check if the device starts properly. Type Ctrl-A Q to exit from minicom.
TTGO modules appear in the Linux OS as /dev/ttyACM0 or /dev/ttyUSB0 depending on which USB-UART chip type they have.
To see the serial ports, type:
ls -ltr /dev/tty*
and the most recently created ports appear at the bottom of the list
If you have no rights to access the serial port then:
- DO NOT run platformio commands with sudo
- type sudo usermod -aG dialout and relogin: you should now be able to access the serial port
- if the above does not work: type sudo chown : to become the owner of the port
You can talk to the tracker on the serial console using a terminal emulator, e.g. minicom
With minicom it is important to:
- turn OFF Hardware Flow Control in Serial port setup
- turn ON Add carriage return in Screen and keyboard You can set those permanently by typing sudo minicom -s setting those items and Save setup as dfl in the menu.
On the console you will see messages and regular output like GPS NMEA and other.
You can send setup commands like $POGNS,AcftType=2 to tell the aircraft is a towing plane
When you press Ctrl-C you will see other parameters you can set.
The code is adapted to the given module at compile time and there are as well various options/functions: some are configured at compile time and some other at runtime.
- Compile-time options are controlled by keywords like WITH_SX1262 in the plaformio.ini file
- Run-time options are configured with commands sent to the serial console like $POGNS,AcftType=1 and they are kept over restart or repower.
There are three elements here:
- aiecraft address: 24-bit number
- aircraft address-type: 1=ICAO, 2=FLARM, 3=OGN
- aircraft type: 1=glider, 2=towplane, 3=helicopter, ...
Suppose you setup a tracker for a towplane with ICAO hex address 4ABCDE - you send the following to the serial console:
$POGNS,Address=0x4ABCDE,AddrType=1,AcftType=2
Note "0x" in front of a hexadecimal number
The OGN-Tracker detects take-off and landing and records the position/altitude/speed/climb points every few seconds. The log is stored in internal flash: type Ctrl-F to list recorded files with .TLG extension.
The files can be as well automatically uploaded via WiFi to a configured URL using the HTTP POST method:
You need to setup the following elements:
- WiFi name to connect to internet and password: suppose they are "OurClub" and "OurPass"
- Upload URL which accepts files uploaded with POST method
You send the following to the serial console:
$POGNS,UploadURL=http://ogn3.glidernet.org:8084/upload,WIFIname=OurClub,WIFIpass=OurPass
The given upload URL is a real test server which accepts files, but you can run your own. You can find Python and PHP scripts in utils directory of the project.
Tracker's firmware can be updated remotely (Over-The-Air) using WiFi connection. Firstly, tracker flash memory needs to be prepared differently for this - special partition layout is required. This needs to be done traditionally, using serial connection. Once done, a command should be sent via serial console:
$POGNS,FirmwareURL=https://example.com/ogn/firmware/my_firmware.bin,WIFIname=OurClub,WIFIpass=OurPass
In this example, tracker expects two files at https://example.com/ogn/firmware/:
- my_firmware.bin
- my_firmware.bin.serial The latter is a mandatory text file with firmware serial, suggested format is 2025102701 (YMD date and daily version number). Tracker checks this value against current serial to decide if new firmware has been published. If new number is higher, an OTA update is performed.
OTA process has an auto-rollback feature which expects tracker to connect to a WiFi after first boot with new firmware (this usually happens within 30 seconds). If no such connection is made, previous firmware is restored and no future attempts will be made to download that failed serial again. It is then crucial to provide a reliable WiFi coverage during OTA process and shortly after.
If you place TRACKER.CFG or WIFI.CFG in project's data/ directory they will be placed in tracker's local filesystem and read during each startup. While any parameter can be defined in any of these two files, it is recommended to separate security-sensitive WIFI/OTA data from general tracker config. Be aware that configuration made by serial console (and stored in NVS memory) can be erased in some OTA scenarios, so using these files is recommended if using OTA.
Example content of TRACKER.CFG:
ID=ABC
AcftType=1
Model=SZD-55
Example content of WIFI.CFG:
WIFIname=OurClub
WIFIpass=OurPass
FirmwareURL=https://example.com/ogn/firmware/my_firmware.bin
UploadURL=https://example.com/ogn/upload/tlg2igc.php
Additionally, optional settings_A1B2C3.txt and wifi_A1B2C3.txt files ("A1B2C3" is tracker's 24 bit address written in uppercase hex) can be placed in the same directory as firmware. If found, they will be downloaded to local filesystem as TRACKER.CFG and WIFI.CFG respectively. Please remember these files are publicly available on WWW, be careful when passing any keys/passwords there. Basic HTTP-AUTH can be used in URLs to reduce exposure.