Pat’s submerged Pi experiment. The objective was to measure lake water temperature through fall, winter and spring. I decided to put the Pi inside a water proof pipe anchored in 3′ of water. Power over Ethernet was used to power the Pi, data reported back from the Pi over the Ethernet cable.
Some weeks after launching, the Pi started reporting zeros for temperature value. I could still ssh into the Pi from home so it was alive. Apparently the the sensor wire had come loose from the GPIO, inside the pipe, maybe from motion of the enclosure under water, clearly I didn’t connect it well enough.
Once the lake surface froze I went out to investigate and decided to recover the Pi and fix the connection problem.
It took five or six holes through the ice to actually find the rope and hook onto it and pull up the Pi. In sub freezing temperature I repaired the sensor connection and the Pi began reporting temperature again. I let it down back into the water. Within 12 hours it stopped working altogether. The cold temperature proved too much of a challenge to seal the pipe back up properly and so it sprung a leak. In the spring I fished out the Pi.
It was a good project even if it eventually failed. Lots learned. The idea of a submarine Pi is still intriguing. Maybe one day.