The Story Behind the Project
My girlfriend and I were going on a two week vacation, and she worried her Christmas Tree would dry out and drop needles while we were gone. Before she could give her key to a friend to water it in her absense, I stepped in with a much better* solution! I took an old fountain pump that I've been wanting to use for awhile now, and repurposed the Chandalier Dropper circuit board that I'd recently built for a friend's Phantom of the Opera movie night. I was too scared to fully automate something that had the power to dump water everywhere if it malfunctioned, so instead I made it remotely operated. Over the course of our break, we had fun watering her Christmas tree from various airports and beaches in the Philippines. Apologies for the poor photography of this project -- I finished it the night before we flew out and didn't take many pictures.
*probably much worse
Three water-level sensors to indicate whether the water level is low, medium, or full.
Emergency fill: If the water drops below critical level, the pump will automatically turn on for 30 seconds... but it will only do it once to avoid triggering repeatedly in the case of bad sensor data! When the user asks for the status, it will report that it operated an emergency fill, and gives the user the option to re-arm the system.