Capacitive water level sensor based on a custom Arduino-based board.
This project started as an experiment to see if a water level sensor (with fixed intervals) could be built, using the Arduino ADCTouch library and capacitive sensors. Capacitive sensors have the advantage that they can be isolated from water, creating a water-tight sensor.
In this repository, you can find the CAD designs, firmware and 3D printed parts to create a water level sensor.
- Small board that finds in a 19mm tube.
- 4 channels/board, can be daisy-chained up to 8 boards.
- I2C connection.
- Temperature sensor.
- The
3d/folder contains a 3D-printable designs for the necessary parts. - The
applications/folder contain applications and drivers that can interact with the sensor. - The
firmware/folder contains the Platform.IO-based firmware that runs on the sensors. - The
pcb/folder contains the Kicad schema and board design.
Several proof of concepts have been built, to validate the idea and the sensitivity of the setup in a 19mm PVC pipe (electrical conduit pipe). This pipe was perfect for my 400 liter rain barrel, only occupying 0.5 L of water.
To create the fixed intervals, I 3D printed coils that I wound using 1.5 mm² electrical wire. I could not get copper/aluminium tube that fitted exactly in the 19mm tube, and this 'solution' somewhat expands against the inside of the tube, ensuring as little as possible air between the tube and the coil.
In total, I used 4 sensor boards, connecting a total of 16 intervals, or 25 liter per interval. The picture below shows render of how one sensor board is used for four intervals. Four of these assemblies are daisy-chained together. The parent board is then connected to an external application to read the sensor.
The work in this repository is covered by CC BY-NC-SA 4.0. See the LICENSE.md
file for more information.
Some parts of this project are covered by a different license.