Video Showcase of the project Video: https://www.youtube.com/watch?v=Hn0Y_s4RmP8
A project inspired by the YouTube Channel Practical Engineering on this video
An Arduino Uno Wifi Rev 2 collect temperature and humidity data every 15 minutes from the soil using 2 analog sensors, and from the air using 1 digital sensor. It then uses the WIFININA library to send the data from the sensors to a timeseries database called InfluxDB on a Home Assistant VirtualBox Virtual Machine using the inbuilt REST API.
The arduino also controls a 12V 3/4 inch valve, that opens once a day for 2 minutes, provided it has enough pressure from the hose at the input end.
To connect the Arduino to Wifi, you'll need to create a file named arduino_secrets.h and define a few macros in there like so:
───────┬───────────────────────────────────────────
│ File: arduino_secrets.h
───────┼───────────────────────────────────────────
1 │ #define SECRET_SSID "WIFI_NAME"
2 │ #define SECRET_PASS "WIFI_PASSWORD"
3 │ #define DB_USER "USERNAME THAT THE ARDUINO WILL USE TO LOG INTO THE DATABASE"
4 │ #define DB_PASS "PASSWORD THAT THE ARDUINO WILL USE TO LOG INTO THE DATABASE"
───────┴───────────────────────────────────────────
To do the wiring for the Solenoid Valve, follow this tutorial: https://bc-robotics.com/tutorials/controlling-a-solenoid-valve-with-arduino/
To do the wiring for the DHT22 temperature and humidity sensor for the air, use this guide: https://create.arduino.cc/projecthub/mafzal/temperature-monitoring-with-dht22-arduino-15b013
To do the wiring for the LM35 soil temperature sensor, use this guide: https://lastminuteengineers.com/lm35-temperature-sensor-arduino-tutorial/
To do the wiring for the soil humidity sensor, use this guide: https://create.arduino.cc/projecthub/MisterBotBreak/how-to-use-a-soil-moisture-sensor-ce769b
- 12V SOLENOID VALVE - 3/4" - €7.9800
- ARDUINO UNO WIFI REV2 - €40.2400
- BATTERY HOLDER 1X9V WITH JST CONNECTOR & SWITCH - €0.7300
- TEMPERATURE SENSOR - WATERPROOF (LM35) - €4.4400
- WAVESHARE TEMPERATURE-HUMIDITY SENSOR DHT22 - €8.7900
- 12V Lead Battery - €6.90
- TIP120 Darlington Transistor - €0.50
- 1K Ohm Resistor - €0.0200
- 1N4001 Diode - €0.04
Total cost (without VAT, wires, connectors, solder, and the tools):
€70.14