Plant Watering Smart Buckets
Going away? Need to remotely water your plants?! You need one of these!
Going away? Need to remotely water your plants?! You need one of these!
Status | Operational |
Platform | D1 Mini ESPHome |
Budget | $50 |
Date Completed | December 2020 |
Summary of operation
Basically it's a bucket of water with a small submersible water pump that sits in the bottom and waters the plant via clear vinyl hose.
To make it remotely operate, and for some extra features, it also includes a sensor to measure the soil moisture, as well as a level meter in the bucket.
It runs ESPHome software for operation via Home Assistant!
It does need a 12VDC power supply to run the pump - so unfortunately needs to plug in. But hey - maybe a future improvement could be battery power.
Parts used
- ESP8266 D1 Mini (knock off) - search D1 Mini on eBay or Amazon and buy them in lots of 5 or 10!
- 5V 1-channel relay module to control the pump. https://core-electronics.com.au/5v-single-channel-relay-module-10a.html
- Submersible water pump - I used the DFRobot brand https://core-electronics.com.au/immersible-pump-water-tube.html
- Gravity VL53L0X ToF Laser Range Finder. Measures depth of water in the bucket. https://core-electronics.com.au/gravity-vl53l0x-tof-laser-range-finder.html
- Capacitive soil moisture sensor. More reliable than the conductivity type. https://core-electronics.com.au/gravity-analog-waterproof-capacitive-soil-moisture-sensor.html
- Custom PCB I made using the toner-transfer method. Try YouTube for examples like this - https://www.youtube.com/watch?v=cVhSCEPINpM
- 3D printed enclosure based on the "Ultimate Parametric Box". https://www.thingiverse.com/thing:1355018
- Runs ESPHome and is available in Home Assistant.
Some engineering detail
The circuit board is really basic. It just connects a GPIO output from the D1 Mini to the relay board. The 2 headers are i2c with power and ground. The soil sensor is i2c and so is the laser range finder for the bucket water depth.
Made it using the cold/acetone toner transfer method and etched in warm ammonium persulfate (first photo). Finished an assembled PCBs shown in the following images.
Future improvements
Some ideas for future improvements:
- Battery operation. Would need timer/interrupt method to wake up the device say every couple of hours to see if watering has been cued in the meantime. Otherwise the WiFi will run the battery flat!
- Better soil sensors. I don't know what it is with soil sensors - but they're all pretty average. I think there's better types which go on a leaf to measure light passing through?
- Peristaltic style pump for a measured dose of water. These pumps I used were just cheaper and easier. But not accurate in terms of water they deliver as they're very dependent on the head pressure of the pipework.
- Button to press to water locally from the unit.