Glossary

Glossary

Short, plain-language explanations of the terms that come up around BoatOS — for everyone who isn't a professional inland skipper or a GIS person.

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AIS — Automatic Identification System. Vessels broadcast their position, course and speed. BoatOS shows other ships on the chart, either via AISStream.io over the internet or from a local USB AIS receiver.

BoatOpenIO — the companion project: a modular ESP32 gateway that connects old analogue marine sensors (VDO temperature, oil pressure, tank senders) to BoatOS over MQTT. See Hardware.

CEVNI — the European code for inland waterway signs and signals (Code Européen des Voies de Navigation Intérieure). These are the traffic signs of the rivers and canals. BoatOS renders them from the official chart data, including as 3D boards in the v1.9 dev branch.

Deck — the browser-based frontend. Runs on any phone, tablet or laptop on the same network, no installation needed. One of the two BoatOS user interfaces.

Helm — the native touchscreen frontend (Flutter, via flutter-pi). The optional touchscreen at the helm station. The other of the two interfaces.

ELWIS — Elektronisches Wasserstraßen-Informationssystem, the information service of the German waterways administration (WSV). Source of the official inland charts (IENC) and the sign artwork. Free of charge.

flutter-pi — a lightweight runtime that renders Flutter apps directly on the Raspberry Pi's GPU without a desktop. This is how Helm runs in kiosk mode.

IENC — Inland Electronic Navigational Chart. The official electronic charts for inland waterways, published by the waterways authorities. The same charts professional inland shipping uses. BoatOS downloads and converts them on the Pi.

MBTiles — a single-file format for storing map tiles (essentially a SQLite database). BoatOS holds its offline maps as .mbtiles files; the MBTiles Creator is the Windows tool that builds them.

MQTT — a lightweight publish/subscribe messaging protocol. BoatOpenIO and other sensors publish their values as MQTT topics; BoatOS subscribes and auto-discovers them.

mDNS / .local — the mechanism behind names like boatos.local — no DNS server needed, the device announces its own name on the local network. Note: Firefox with DNS-over-HTTPS can't resolve .local, see Common Pitfalls.

OSRM — the routing engine BoatOS uses, tuned for rivers, canals and locks rather than roads. Runs locally on the Pi.

OpenSeaMap — the community sea-mark layer built on OpenStreetMap data. BoatOS uses it for the sea-mark overlay and for anchorages.

PEGELONLINE — the German waterways authority's live water-level service. BoatOS shows gauge readings on the chart and derives the tidal curve from it.

S-57 — the international standard format the IENC charts are delivered in. BoatOS converts S-57 cells into vector tiles on the Pi so they can be drawn in Deck and Helm.

SignalK — an open marine data standard. On BoatOS it reads the GPS receiver (NMEA) and provides the position; the backend consumes it.

topmark — the small shape on top of a buoy or beacon (a cone, a cylinder, crossed cones …) that encodes its meaning. In the 3D view BoatOS renders these from the chart attributes, not from a lookup table of pictures.

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Missing a term? Add it — the wiki is editable. See Home.