SMARTSPACEBUCKET

SPEC-01.07 · HARDWARE · ESP/MQTT

Distributable hydroponic urban agriculture. ESP-class microcontrollers, MQTT, 3D-printed retrofits.

SmartSpaceBucket grow computer enclosure with sensors and pump interfaces

GitHub

An indoor agriculture stack designed to be cheap, distributable, and built from off-the-shelf parts plus a few 3D prints. The goal: every node in a grow network is a small ESP-class board exposing MQTT topics for sensors, pumps, fans, and lights — drop one in, it joins the mesh; a dockerized server times the whole thing.

Stack

ESP32 / ESP8266 / ESP01: Three classes of node — the ESP01 is small enough to live inside an inline valve; ESP32 handles the grow computer with sensors, fans, pumps.
MQTT: Pub/sub bus between every node. Scheduling, sensor telemetry, and pump dispatch all ride the same broker.
Arduino C++: Firmware for each node class. Common HAL across boards, board-specific pin maps.
Embedded web UI: Each node ships a tiny config page over WiFi for first-pair, calibration, manual override.
3D-printed retrofits: The first iteration is a print that attaches to a stock kitchen sprouter — the sprouter parts stay dishwasher-safe; the 3D print never touches food. Auto-drains via 1/4" OD tubing.
Peristaltic pumps: Accurate nutrient dosing without contaminating the pump head. Driven by the doser node.
Fusion 360 CAD: All mechanical parts modeled parametrically — bucket adapters, grow computer enclosure, doser body.
Docker (planned server): Iteration 3 is a dockerized scheduler that drives the whole network from a single image.

Process

Three iterations, each one solving the problem the last one revealed.

Multi-function display node for SmartSpaceBucket — Multi-function display node — local status surface for a single bucket.

Iteration 1 — Sprouter retrofit (complete). Start with the cheapest microgreen sprouter on Amazon. It requires 2–3 waterings a day and you have to dump leftover water from the bottom tray. The retrofit prints an attachment for the top reservoir and a drop-in replacement for the bottom tray, both with 1/4" OD tube fittings. Pair with a valve node or a pump-plus-reservoir node and the whole thing waters itself. The print never contacts the sprouts — the sprouter's own (dishwasher-safe) parts do.

Web UI for stackable doser node — Stackable doser node — peristaltic pumps drive accurate per-channel nutrient dosing. Each unit registers itself on MQTT.

Iteration 2 — Grow computer (in progress). A fully contained node: ESP32 (or ESP8266) with soil-moisture and temperature probes, I²C out for pump dispatch, integrated fan control off an off-the-shelf PC fan, and a web interface. Sensor inputs are plug-and-play via a PCIe-style USB adapter so the same enclosure works whether you have one probe or four.

Web UI for valve node — Valve node web UI. Every node ships its own config page; the broker handles inter-node messaging.

Iteration 3 — Integrated hydroponics (planning). A dockerized server publishes timed alerts on MQTT to a doser bot (precise nutrient dosing), a stir bot (agitating the nutrient solution so it doesn't stratify), and a pump/bucket controller (moving mixed solution from reservoir to plants). A single web interface across the whole network.