ra1fh / airtraffic

NMEA/FLARM and GDL90 Simulator

Airtraffic: NMEA/FLARM and GDL90 Simulator

This is a command line tool to simulate a simple air traffic scenario and send traffic information via NMEA/FLARM or GDL90 protocol to an electronic flight bag application (EFB).

Getting Started

Prerequisites

• Ruby 2.5, 2.6, 2.7 or 3.0, 3.1, 3.2

• Electronic flight bag app (EFB) or other NMEA/FLARM/GDL90 receiver

  • ForeFlight

  • SkyDemon

  • Enroute

Installation

git clone https://github.com/ra1fh/airtraffic.git

Usage

The tool simulates the aircraft position flying east, 5 planes with full position/distance information flying south and one bearingless aircraft flying north, such that the EFB has a lot of traffic to announce.

GDL90

Send GDL90 UDP packets to 10.1.1.1 port 4000:

ruby ./airtraffic.rb --gdl 10.1.1.1:4000

GDL90 does not support bearingless traffic, so the bearingless aircraft is shown as normal traffic.

NMEA/FLARM

Open NMEA listener on port 2000:

ruby ./airtraffic.rb --nmea 0.0.0.0:2000

The target IP is not configurable within the EFB app, so the network has to be set up such that the EFB can connect 192.168.1.1:2000. The network has to route to the listener via port forwarding, dedicated WLAN or other means.

The bearingless aircraft is presented in the NMEA PFLAA record with distance in "RelativeNorth" field and empty "RelativeEast". The only EFB supporting bearingless aircraft is SkyDemon in NMEA/FLARM mode.

Multiple connections are possible.

Usage on OpenWRT

Tested with OpenWRT 22.03.2 on a device with 16M flash.

Connect to the LAN port of device and copy the script:

scp airtraffic.rb [email protected]:    # OpenSSH < 9.0
scp -O airtraffic.rb [email protected]: # OpenSSH >= 9.0

Setup network access via web interface and connect with SSH to install prerequisites:

root@OpenWrt:~# opkg update
root@OpenWrt:~# opkg install ruby ruby-optparse ruby-socket ruby-yaml

Reconfigure the device’s wireless network to "Master" mode, assign an IP and enable DHCP. Connect the EFB to the new wireless network and start the script (you may need to adjust the GDL90 IP):

root@OpenWrt:~# ruby ./airtraffic.rb --nmea 0.0.0.0:2000 --gdl 10.1.1.1:4000

EFB configuration notes

SkyDemon

• NMEA/FLARM

  • Enable the device: Setup → Third-Party Devices → FLARM Devices → Air Avionics AT-1

  • Start with: Fly → Use Air Avionics AT-1

  • SkyDemon will connect to TCP 192.168.1.1:2000

• GDL90

  • Enable the device: Setup → GDL90 Compatible Device

  • Start with: Fly → Use GDL90 Compatible Device

  • Send GDL90 traffic to the IP of your mobile device, destination port 4000

ForeFlight

• NMEA/FLARM

  • ForeFlight automatically connects to TCP 192.168.1.1:2000 on startup

• GDL90

  • ForeFlight automatically opens an UDP listener on port 4000 on startup

  • Send GDL90 traffic to the IP of your mobile device, destination port 4000

  • ForeFlight will try to connect back to the IP sending GDL90 on TCP port 2000 for NMEA and run both protocols at the same time when successful

Enroute

• Open Menu → Information → Traffic Receiver

• The page explains how to connect and allows to trigger connection attempts

Changelog

• 2023-05-30: Added option to load traffic scene from YAML file

• 2023-05-28: Removed EventMachine dependency. Added OpenWRT instructions.

airtraffic's Issues

Send nmea via BT Esp32

Most of the Apps running on a mobile Device supporting BT and or WiFi. Make it usable on a ESP32 devboard as BT emitter, wich is very cheap and easy to get. So in XCSoar, LK8000 or whatever simply select the esp as source getting nmea or gdl data

Thanks

Just wanted to say thanks. 👍

i was able to simulate traffic for https://xcsoar.org (https://github.com/XCSoar) with it and implement the correct recognition of FLARM targets with it.
XCSoar/XCSoar#1228

Regards,

• Folken