Home Florist Monitoring System
Plant soil moisture and surrounding's humidity and temperature monitoring system with buzzer alert and bicolor LED display.
Author: Aleksandar Petreski
GitHub Project Link: GitHub Repository
Description
This project is a smart plant monitor that continuously reads humidity and temperature data using a DHT22 and soil moisture data using a FC-28 sensor. It displays the status on a bicolor LED, turning red when the sensor readings fall below a set threshold and green otherwise. Additionally, the system activates a buzzer alert.
Motivation
I chose this project to apply embedded Rust programming to a real-world, practical use case. It demonstrates the use of multiple hardware peripherals and introduces IoT-friendly monitoring for plant care, which is a relatable and valuable scenario.
Architecture
The architecture consists of the following main components:
- Soil Moisture Sensor Module (FC-28): Measures the soil moisture level using analog output.
- Air Sensor Module (DHT22): Measures ambient temperature and humidity.
- Display Module: Manages output to the bicolor LED screen (red / green).
- Alert Module: Triggers a buzzer when humidity drops below the threshold.
- Controller Module: Central logic running on the Raspberry Pi Pico W to coordinate tasks.
Log
Initially: Brainstormed some project ideas and decided on the final one.
Week 28 April - 4 May: Defined the project scope and wrote the initial documentation.
Week 12 - 18 May: Ordered the components.
Week 19 - 25 May: Put everything together and started building the software.
Week 26 - 29 May: Completed the code and ran the tests.
Hardware
- Raspberry Pi Pico 2W microcontroller
- FC-28 Soil Moisture Sensor (analog output)
- DHT22 sensor for humidity and temperature
- Bicolor LED (red/green)
- Active buzzer
- Breadboard and male-to-male jumper wires
Schematics
Bill of Materials
| Device | Usage | Price |
|---|---|---|
| Raspberry Pi Pico 2W | The microcontroller | 40 RON |
| FC-28 Soil Moisture Sensor | Soil moisture sensor | 35 RON |
| DHT22 Sensor | Temp & humidity sensor | 23 RON |
| Bicolor LED (3mm, common cathode) | Status indicator (red / green) | 1 RON |
| Active Buzzer | Sound alert | 1 RON |
| Breadboard | Prototyping | 3.5 RON |
| 220Ω Resistors (x2) | Current limiting for LED | .2 RON |
| Male-to-male wires | Prototyping | 8 RON |
Software
| Library | Description | Usage |
|---|---|---|
| embassy-rp | Pico 2W HAL | Control GPIO, I2C |
| dht-sensor | DHT22 driver | Read humidity & temperature |
| embedded-graphics | 2D graphics library | Render text and graphics |
| embassy-time | Async timing functions | Manage delays and scheduling |