Documentation

HerdTag documentation

HerdTag is an early-stage virtual-fencing ear tag for cattle.

Architecture

Backend

A FastAPI app (src/herdtag/server/) with SQLite storage.

Fence controller

The controller is the logic that runs on the tag. The reference implementation is src/herdtag/controller.py, and the C port is firmware/core/ht_core.c.

Firmware

The full guide is in firmware/README.md. This page summarises it.

Glossary

Cycle grazing

Move the herd through paddocks on a schedule. You draw each paddock once, then set the order and how long the herd stays in each. The server runs the moves.

Operations runbook

How to run HerdTag tags on a real farm. This is for prototype trials. The virtual fence isn't a safety barrier.

Over-the-air protocol

Two message types travel over LoRaWAN. Both are defined in src/herdtag/protocol.py, and byte-identical in firmware/core/ht_core.c.

Simulation and demo

HerdTag v1: hardware build plan

Every price below is an estimate from listings checked on 2026-11-07. Prices move, and RAK's own store doesn't always include US tariffs.

Enclosure (v1 prototype)

tag_case.scad is a parametric two-part case: base + lid. Every key dimension is a parameter at the top of the file.

herdtag firmware

The test replays 11 scenarios (about 550 controller steps, 3,630 checks) generated by scripts/gen_vectors.py from the Python reference.