🌱 CyberDruid — Smart Soil Moisture Monitoring

An ESP8266-based soil moisture monitoring system with OLED display and Telegram alerts

📖 Introduction

CyberDruid is an intelligent soil moisture monitoring system designed to help you effortlessly water your plant on time. It continuously monitors soil moisture levels using a capacitive sensor, displays real-time data on an OLED screen, and sends Telegram alerts when the soil moisture level drops below a specified threshold.

✨ Features

• Real-time Monitoring: Continuous soil moisture percentage tracking
• Visual Display: 128x64 OLED screen with beautiful visuals
• Smart Alerts: Telegram notifications when moisture level drops below threshold
• Rolling Average: Smoothed readings to prevent false alarms
• Visual Feedback: Screen inversion when plant needs water
• WiFi Connectivity: Remote monitoring and alert system

This basil was not doing well before CyberDruid was installed!

🔧 Components Required

Component	Quantity	Description
Wemos D1 Mini	1	ESP8266 development board
SSD1306 OLED Display 0,96''	1	128x64 I2C OLED screen
Capacitive Soil Moisture Sensor v1.2	1	Analog moisture sensor
Resistor 10kΩ & 20kΩ	1 each	For voltage divider
Some Wires	some	For connections
Breadboard & Jumper Cables	1 & some	For prototyping (optional)
Micro USB Cable	1	For power and programming
Plant Pot	1	Your favorite plant

🔌 Wiring Diagram

Wiring diagram for connecting the components

Pin Connections

Wemos D1 Mini	Component	Connection
D1	OLED SCL	Clock line
D2	OLED SDA	Data line
A0	Moisture Sensor AOUT	Analog output
3.3V	OLED VCC	Power
5V	Moisture Sensor VCC	Power
GND	OLED GND	Ground
GND	Moisture Sensor GND (through voltage divider, see schema)	Ground

🤖 Telegram Bot Setup

Step 1: Create a Telegram Bot

1. Open Telegram and search for @BotFather
2. Start a chat and send /newbot
3. Follow the prompts to name your bot
4. Save the Bot Token provided (format: 123456789:ABCdefGHIjklMNOpqrsTUVwxyz)

Step 2: Get Your Chat ID

1. Send a message to your newly created bot
2. Open this URL in your browser (replace YOUR_BOT_TOKEN):

   https://api.telegram.org/botYOUR_BOT_TOKEN/getUpdates
   

3. Look for "chat":{"id":123456789} in the response
4. Save this Chat ID number

💻 Local Setup

Step 1: Install Arduino IDE & Configure ESP8266 Board

1. Download and install Arduino IDE from arduino.cc
2. Open Arduino IDE and go to File → Preferences
3. Add this URL to Additional Board Manager URLs:

   http://arduino.esp8266.com/stable/package_esp8266com_index.json
   

4. Go to Tools → Board → Boards Manager
5. Look for "esp8266" and select LOLIN (WEMOS) D1 R2 & mini

Step 2: Install Dependencies

1. Go to Sketch → Include Library → Manage Libraries
2. Install these libraries:
   • Adafruit SSD1306 by Adafruit
   • Adafruit GFX Library by Adafruit
   • Adafruit BusIO by Adafruit
   • LiquidCrystal I2C by Frank de Brabander

⚙️ Code Configuration

Step 1: Download the Code

Clone or download this repository to your computer.

Step 2: Configure Secrets

Open cyberdruid/config.hpp and update the following values:

const String WIFI_SSID   = "Your WiFi SSID"; // Your WiFi network name
const char   WIFI_PASS[] = "XXX"; // Your WiFi password  
const String BOT_TOKEN   = "0000000000:AAAAAA...AAAAAA"; // Your Telegram bot token
const String CHAT_ID     = "123456789"; // Your Telegram ID

Step 3: Calibrate Sensor Values

You may need to adjust these values based on your specific sensor:

// Sensor Calibration
const int SENSOR_DRY_VALUE = 395;  // Value when sensor is dry (in air)
const int SENSOR_WET_VALUE = 260;  // Value when sensor is wet (in water)

To calibrate:

1. Hold the sensor up in the air → note the reading
2. Place sensor in a glass of water → note the reading
3. Update SENSOR_DRY_VALUE and SENSOR_WET_VALUE accordingly

Step 4: Customize Plant Settings

// Plant Configuration
const String PLANT_NAME = "Basilikum";           // Your plant's name
const uint8_t MOISTURE_THRESHOLD = 50;           // Alert threshold (0-100%)
const unsigned long ALERT_COOLDOWN = (6UL * 60 * 60 * 1000); // 6 hours between alerts

If you want to change the plant icon, you can create a new bitmap using an online tool like dot2pic.com and update bitmaps.hpp (please submit a PR if you add more icons).

Optimal image size is 40x40 pixels, update IMAGE_HEIGHT & IMAGE_WIDTH constants if you change dimensions. Bitmap should be monochromatic with 8 pixels per byte in horizontal order.

🚀 Upload and Run

Step 1: Connect Hardware

1. Connect all components according to the wiring diagram
2. Connect Wemos D1 Mini to your computer via USB

Step 2: Upload Code

1. Open cyberdruid/cyberdruid.ino in Arduino IDE
2. Select the correct COM port: Tools → Port → COM[X]
3. Click the Upload button (→)
4. Wait for "Done uploading" message

Step 3: Monitor Serial Output

1. Open Tools → Serial Monitor
2. Set baud rate to 115200

🔧 Troubleshooting Common Issues

OLED Display Not Working:

• Check I2C connections (see wiring diagram)
• Verify display address (default: 0x3C)
• Use find_display_addr.ino to scan for I2C devices

WiFi Connection Failed:

• Verify SSID and password in config.hpp
• Check WiFi signal strength
• Ensure 2.4GHz network (ESP8266 doesn't support 5GHz)

Telegram Alerts Not Sending:

• Verify bot token and chat ID
• Check internet connection
• Monitor serial output for error messages

Inaccurate Moisture Readings:

• Calibrate sensor values for your specific soil type
• Check the wiring (must be powered with 5V)
• Ensure sensor address is correct in config.hpp

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request with any improvements, bug fixes, or new plant icons.

📦 Designing a 3D printable case for sensor protection and aesthetics would be much appreciated!

📄 License

This project is licensed under the MIT License — you can freely use, modify, and distribute it.

---

Happy Home Gardening! 🌱