KSPBridge

MQTT telemetry bridge for Kerbal Space Program 1.12.5. The plugin runs inside KSP and publishes real-time vessel telemetry over MQTT so browsers, dashboards, ESP32 microcontrollers, Grafana, voice agents, hardware control panels, or any MQTT subscriber can consume live flight data.

Wire format mirrors KSA-Bridge exactly (the Kitten Space Agency counterpart), so consoles built for one game work against the other with only a topic-prefix change.

What it publishes

Eighteen telemetry topics, all under the configured prefix (default ksp/telemetry/*):

• 10 Hz — vehicle, navigation, attitude (with full Unity quaternion), state_vectors, target/vehicle, target/state_vectors, target/attitude
• 5 Hz — dynamics (body rates + linear/angular acceleration + g-load), atmosphere (density, pressure, temperature, Mach)
• 2 Hz — orbit (full Keplerian set), parent_body, maneuver, encounter, performance (ΔV, TWR, mass, thrust), resources (per-resource amount + mass)
• 1 Hz — situation (expanded Vessel.Situations flags), staging (next-stage composition, retained), docking/context (engagement state, retained)

Plus _bridge/status (retained) for liveness with Last-Will-and-Testament on disconnect.

Full schema reference: docs/TOPICS.md.

Installing

1. Download the zip below.
2. Extract into your KSP install root (the folder containing KSP_x64.exe). The zip's GameData/KSPBridge/ folder lands alongside KSP's GameData/Squad/.
3. The shipped Settings.cfg defaults to localhost:1883, which works out of the box if you have Mosquitto running on the same machine. For a remote broker, edit GameData/KSPBridge/Settings.cfg and set broker_host to its hostname or IP.
4. Double-click GameData/KSPBridge/install-check.bat to verify every prerequisite is wired up — KSP install, plugin DLLs, broker reachable, MQTT round-trip, WebSocket listener, FDO console assets, web server smoke test. After all checks pass, the script offers to launch the FDO browser console for you.
5. Launch KSP. Telemetry begins as soon as you reach the flight scene.

Bundled FDO browser console

A hard-scifi mission-control dashboard ships in the source repo at consoles/hard-scifi/. Three.js draws the planet and orbit; panels pull live data from the topics. Body-aware contour pipeline covers every stock world (Kerbin, Eve, Moho, Ike, Tylo, Vall, Laythe, Gilly, Bop, Pol, Minmus, Eeloo, Dres, plus Jool's cloud bands).

The console takes a ?broker= query-string override so the same file works against localhost or a remote broker without edits.

Compatibility

• KSP 1.12.5 (declared range: 1.12.0 - 1.12.5).
• KSA-Bridge wire-format compatible — any KSA-Bridge subscriber works with KSPBridge after a topic-prefix change.
• Two extra correlation fields KSA-Bridge does not emit: id (Vessel.id Guid as a string) and persistentId (Vessel.persistentId uint), so consumers can key telemetry to specific vessels reliably across save/load.

Source, issues, full docs

github.com/johnmknight/KSPBridge

MIT-licensed. Issues and PRs welcome.