MiteOS is a small, cheap and (maybe one day) rugged data recorder for scientific fieldwork, built on affordable off the shelf hardware for a little under 100 GBP. It records where you are and what you measure, with some redundancies built in. It lets you add notes and voice memos.
Why I built it
I built MiteOS to make recording data during my PhD easier, simpler, and more robust. I used the Thinozercon Project as a testing ground to prove it out in the field, collecting the first field data of its kind on Welsh shores, focused on mesofaunal mites.
What it does
- Records your location and sensor state. Onboard GNSS (GPS) tags each event with a position, and you add fields such as sensor state or specific notes.
- Interfaces with many sensors. The current build reads a four channel soil probe over RS485 (moisture, temperature, EC, and pH), and the platform is built to take other sensors.
- Notes and voice notes. Free text notes and short voice memos ride along with each event and are tied to its identifier. The Cardputer ADV is great because it lets you type in long, detailed notes on a tiny keyboard.
- Sampling waypoints (planned). A future build will log waypoints of the locations you plan to sample.
Built to be trusted with data
- Power loss safe saves. Every save is a transaction with a journal. Cut the power in the middle of a save and, on reboot, recovery restores exactly one row, never zero and never two.
- Reliable sensors. A probe read takes three frames a second apart, keeps the median, and reports the spread. A failed read is recorded as an error, never as a fake zero. These are still cheap sensors, but we do our best.
- Identifiers that survive a wet label. Sample identifiers carry a check character, so a single misread or transposed character is caught at ingest rather than in the dataset, and reserved numbers are never reused. In the future these identifiers will be scanned on the device and tied to a specific sample bag.
- Identifiable export. Each row carries its own checksum and firmware provenance, and the USB export ships a SHA-256 for every file, so the laptop can prove it received exact bytes.
The hardware
- M5Stack Cardputer ADV, a pocket computer with a full keyboard and a bright screen.
- A GNSS and radio hat (Cap LoRa 1262) for positioning.
- A DFRobot compatible RS485 soil probe reading moisture, temperature, EC, and pH.
The whole kit comes in at a little under 100 GBP (depending on supplier), which puts a capable, auditable field recorder within reach of students, community groups, and small projects.
Try it
The interactive demo is a mostly faithful to life, playable simulation of the real firmware, down to the key map of the Cardputer keyboard. Walk through a soil trip, take a reading, and save a record. Then pull the power during a save and watch boot recovery restore your row.