Field notes from a very small ocean observatory
One solar wave buoy, one mooring off Marbella, and everything we learn the hard way: the electronics, the deployments, the failures, and what the data quietly reveals about both the sea and ourselves.
A day in the life of a buoy
18% battery on a sunny day, and every sensor swearing it was fine. How a flat battery, a cold hull and a lying motion sensor gave the whole game away — before the jet ski even left the dock.
The daily heartbeat
One cell, one small panel, no way to plug her in. How she found a steady rhythm, arriving at almost exactly the same charge every dawn, with the live chart to prove it.
The sea, in numbers
Three weeks of real measurements: the season in five words, an 11-degree temperature crash, and the day we made four weather models argue and let the buoy settle it.
She's on a leash 50 metres long
How the anchor watch keeps an eye on a buoy in open water, what happens the moment she drags, and how we find her on a map.
The upload that could never succeed
For four days the buoy politely asked to deliver one recording, and the server politely refused. On half-finished migrations, wasted sunshine, and teaching a machine when to give up.
Deployment day: we said 0.12, she said 0.117
Back on her mooring after a week of surgery, and within the hour, the best validation a wave buoy can get: three people floating next to her, guessing.
A mixing desk for the sea
Every 205-second recording can now be taken apart like a song: eight component tracks with mute and solo, a spectrum you can notch, and a rhythm view that finds the sea's repeat patterns.
Mission Control: what it takes to run one buoy
Firmware updates by cellular in 20 KB patches, an anchor watch, a provenance ledger, and a live mode where a 3D buoy mirrors the real one's every tilt.
You can see a lid opening from the battery data
Charging flat-lined at midday and the telemetry knew why before we did: the top was off. A small story about how much a fuel gauge sees.
The two-hour silence
The solar panel was found floating on its cable, the box half out of its seat, and the buoy went quiet. What a power cut looks like from the inside, and how she came back.
What's inside the yellow buoy
The whole instrument is five small boards and a lot of opinions: a motion sensor sampled five times a second, a cellular modem, a fuel gauge, and a solar charger that knows when to stop.