Project · draft
Compost Health Probe (Temperature + Moisture, Low-Power)
- beginner
- 5-7 hours
SDG 12 · Responsible Consumption and Production
Helps a home, school or campus compost kitchen waste well, reducing waste sent to landfill (target 12.5).
Safety notes
- LiPo: use a cell with a protection circuit, check polarity before connecting to the XIAO BAT pads, never puncture, crush or short it, and stop using a swollen cell. Keep the battery and board in a sealed housing outside the heap; only the probes go in.
- Compost can carry pathogens: wear gloves and wash hands after handling.
Draft and unofficial, not affiliated with Fab Academy or the United Nations. Check prices, GST and parts before you buy.
Summary
Push the steel probe into the heap; every 15-30 minutes the node wakes, reads core temperature and moisture, sends them to a dashboard and sleeps. It tells you when to turn the pile or add water.
What it teaches
Read a 1-Wire temperature probe and a capacitive moisture sensor, use deep sleep to run for weeks on a LiPo, report over Wi-Fi, and interpret the hot-composting temperature curve (warm-up, hot phase, cooling).
Topics it touches, in Fab Academy-style terms:
- Input devices
- Embedded programming
- Networking and communications
- 3D scanning and printing
Parts list
Parts cost
Some parts are not priced yet, so there's no total.
4 required parts are marked not priced yet below, and 1 optional. Where a price is known it is shown per part, GST-inclusive as the seller listed it on 24 Oct 2026, with the GST rate unverified. Shipping is not included.
| Part | Qty | Unit | Price, GST-incl. as listed | Line cost | GST | Source |
|---|---|---|---|---|---|---|
| Seeed Studio XIAO ESP32C3 Wi-Fi & BLE Development Boardxiao-esp32c3 | 1 | pcs | ₹734 | ₹734 | GST unverified, typically 18% | Robocrazeread 24 Oct 2026 |
| DS18B20 waterproof temperature probe (1-Wire), ~1 m leadds18b20-waterproof | 1 | pcs | not priced yet | not priced yet | GST unverified | no seller yet |
| 4.7 kOhm resistor, through-hole (pack of 10)resistor-4k7-x101-Wire pull-up; uses 1 | 1 | set | not priced yet | not priced yet | GST unverified | no seller yet |
| Capacitive soil moisture sensor (v1.2/v2 style)soil-moisture-capacitiveSeal the exposed edge | 1 | pcs | not priced yet | not priced yet | GST unverified | no seller yet |
| LiPo cell 3.7 V ~500 mAh with protection circuit and JST leadlipo-3.7v-500mah-jst | 1 | pcs | not priced yet | not priced yet | GST unverified | no seller yet |
| 40x1 Pin 2.54mm Pitch Male Berg Stripheader-male-40x1 | 1 | pcs | ₹8 | ₹8 | GST unverified, typically 18% | Robocrazeread 24 Oct 2026 |
| Male to Female Jumper Wires (20cm) (20pcs)jumpers-f2m-20cm-20Pack: pack of 20 male-female 20cm | 1 | set | ₹28 | ₹28 | GST unverified, typically 18% | Robocrazeread 24 Oct 2026 |
| Part | Qty | Unit | Price, GST-incl. as listed | Line cost | GST | Source |
|---|---|---|---|---|---|---|
| Type C USB Cable (1 metre)cable-usb-c-1mSkip if you already have a data-capable USB-C cable | 1 | pcs | ₹65 | ₹65 | GST unverified, typically 18% | Robocrazeread 24 Oct 2026 |
| PETG 3D printer filament, 1.75 mm, 1 kgfilament-petg-1kgOutdoor housing; Fab Lab stock if available | 1 | pcs | not priced yet | not priced yet | GST unverified | no seller yet |
The Part column links to the shared catalogue. Units are pcs, m, g, sheet or set, and a "set" is the seller's pack, as noted per part.
Tools you will need
- 3D printer (PETG preferred for outdoor housing)
- Soldering iron
- Laptop with Arduino IDE or MicroPython
Build notes
Step-by-step build notes have not been written yet for this draft. The summary, the topics above and the parts list are what exists so far.
How to buy
There is no online checkout. To buy or import these parts, email info@curiosta.com and say what you need. The button opens your own email app with a draft; nothing is sent until you send it.
Prices on this site are third-party seller listings, not a Curiosta quote. Ask by email for availability, price and GST.