TAK Bridge

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2026-06 · drones · fpv · tak · mavlink · telemetry · python

Puts a hobby drone on a TAK map — radio in, live track and video out to the team.

A dark desktop window titled THTakBridge with a green "GOOD (telemetry steady)" banner, drone and operator name fields, a stats block, and a color test-pattern video thumbnail. — Status window mid-session — steady telemetry, 219 CoT events pushed, video broadcasting (bench demo over loopback)

The same window with a dark-red "NO DATA (connecting)" banner, an empty drone field, and all stats showing em-dashes. — Before a radio speaks — the supervisor waits and retries rather than exiting

Terminal window showing two flight rows with start and end timestamps, durations, and point counts, then a jq dump of one exported GeoJSON feature's properties. — The flights CLI — two logged flights listed, then one exported GeoJSON feature's properties

What it is

Team Awareness Kit (TAK) is the shared live map used by search-and-rescue and public-safety teams — anything with a beacon shows up as a marker on everyone’s device. Hobby first-person-view (FPV) drones aren’t one of those things. TAK Bridge fixes that: plug the drone’s handheld radio into a laptop and the drone becomes a live track on the team map, camera feed included.

Why it exists

I wanted the situational awareness of an expensive integrated drone using the FPV gear already on my bench — a RadioMaster handheld running ExpressLRS and a cheap HDMI capture card. Nothing off the shelf bridged that gap.

What it does today

Reads MAVLink (the Micro Air Vehicle Link telemetry protocol) from the radio over USB serial at 460,800 baud, or passively from a UDP forward so Mission Planner can share the same radio. Decodes both ArduPilot and Betaflight flavors.
Publishes each GPS fix as a Cursor-on-Target (CoT) event — up to 2 per second, latest-wins so the marker never lags a slow link — over plain TCP or mutual TLS (Transport Layer Security). Verified against FreeTAKServer with ATAK (Android TAK) phones.
Pushes capture-card video as H.264, scaled to 1280 wide at level 4.1 (the cap Android decoders actually accept), to a MediaMTX relay. The stream URL rides inside the drone’s map marker, so tapping it in ATAK opens the feed.
Supervises itself. Unplug the radio, lose the link mid-flight, replug — it reconnects and resumes without touching anything. A small status window shows link confidence, GPS fix, satellite count, battery voltage, and an embedded video preview.
Logs every pushed point twice: a local JSON Lines flight log per connection, and a server-side collector that records everything the TAK server forwards. Each is the other’s backup against comms loss.
Rebuilds a day’s flying from either log with a small CLI: splits flights at silence gaps, de-duplicates the two sources, exports GeoJSON.

Under the hood

Python 3.11+ asyncio on Windows and macOS: PyTAK for the server connection, pymavlink for decode, ffmpeg for capture and encode, Tkinter for the status window. Decision logic lives in pure, I/O-free modules built test-first (255 tests, strict mypy); hardware I/O is thin and injected, so the whole telemetry path runs in CI against a fake vehicle and a fake TAK server.

State & direction