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🚀 Humidity Automation 💧

🎯 Project Goal

To build an extremely reliable, Wi-Fi-controlled, and aesthetically pleasing Automated Humidifier Controller using the ESP8266, eliminating the common problems of relay chattering and sensor failure through smart safety logic.

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✨ Edge

Feature	Impact	Status
🌐 Offline Dominance	Full dashboard control without any active internet connection (zero dependency on Google APIs).	✅ DONE
🛡️ Fail-Safe Logic	Critical sensor errors automatically force the humidifier OFF, preventing accidental flooding or burnout.	✅ DONE
🧠 Intelligent Stability	Uses Hysteresis to stabilize switching behavior, maximizing relay life.	✅ DONE
🎨 Hyper-Responsive UI	Fast, dark-mode, mobile-friendly dashboard served instantly from the ESP8266's memory.	✅ DONE

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⚙️ Core Technology

Component	Role	Pins Used (NodeMCU)
Microcontroller	ESP8266	Wi-Fi Station/AP Mode, Web Server
Sensor	DHT22	D2 (GPIO4): Humidity & Temp Data
Actuator	1-Channel Relay	D1 (GPIO5): Humidifier Control (Active-LOW)
Output Device	Humidifier	Generates mist (Ultrasonic/USB Mist Maker)

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🌐 Connectivity

The device attempts to connect to your home Wi-Fi first (STA Mode). If credentials are not set or connection fails, it falls back to a self-created Access Point (AP).

Mode	Network Name	Access IP	Access Requirement
STA Mode (Home Wi-Fi)	Your Router's SSID	192.168.x.xxx	Device must be on the same network.
AP Mode (Direct Link)	BDC_2.0 (Pass: ahmhabib01)	192.168.4.1	No Internet Required. Connect directly to this network.

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🛠️ Setup Guide

1. 🔌 Hardware Wiring

Carefully connect the components as detailed below:

Component Pin	ESP8266 Pin (GPIO)	Notes
DHT22 VCC	3.3V	Power for the sensor.
DHT22 GND	GND	Ground connection.
DHT22 Data	D2 (GPIO4)	Sensor Data Input.
Relay VCC	VIN (5V) / VCC	Relay Coil Power Supply.
Relay GND	GND	Relay Ground.
Relay IN	D1 (GPIO5)	Control Signal from ESP. (Active-LOW Logic)

|Humidifier Power (+) | Connect to Relay NO (Normally Open) terminal|

|Power Source (+) | Connect to Relay COM (Common) terminal|

|Humidifier Ground (-) | Connect directly to Power Source Ground (-)|

⚠️ Safety Note: Connect the humidifier's power line to the relay's Common (COM) and Normally Open (NO) terminals. Never connect high voltage while the ESP8266 is powered on.

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2. 💻 Software and Library Installation

1. Open Arduino IDE and go to File > Preferences.
2. Add the following URL to "Additional Boards Manager URLs":

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

3. Go to Tools > Board > Boards Manager... and search for esp8266. Install the latest package.
4. Go to Sketch > Include Library > Manage Libraries... and install the following:
   • DHT sensor library by Adafruit
   • Adafruit Unified Sensor

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3. ⚙️ Code Configuration and Upload

1. Download and open humidity.ino with Arduino IDE
2. Optional: Update the Wi-Fi credentials for STA Mode (if using your home network):

   const char* ssid = "YOUR_HOME_WIFI_NAME";
   const char* password = "YOUR_WIFI_PASSWORD";

3. Select the correct board (e.g., NodeMCU 1.0) and Port under Tools.
4. Click the Upload button (Right Arrow icon).
5. Wait for the Done uploading. message.

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🖥️ Accessing the Dashboard

1. Open the Serial Monitor (115200 Baud) and wait for the "IP Address" to be printed.
2. Open a web browser (on a device connected to the relevant Wi-Fi network) and enter the IP address.

Mode	Network Name	Access IP	Access Requirement
STA Mode (Home Wi-Fi)	Your Router's SSID	192.168.x.xxx (Dynamic IP)	Device must be on the same home network.
AP Mode (Direct Link)	BDC_2.0 (Pass: ahmhabib01)	192.168.4.1 (Static IP)	Connect directly to the BDC_2.0 network.

💡 Tip: If the dashboard doesn't load in AP Mode, ensure your phone's Mobile Data is temporarily turned OFF.

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🧠 Core Logic: The Hysteresis Principle

Humidity Automation uses a $5%$ hysteresis band to maintain target humidity and prevent short-cycling.

• Target (e.g., 65%): The ideal max humidity.
• Humidifier ON: Only when Humidity $\le$ $60%$ ($\text{Target} - 5%$).
• Humidifier OFF: Only when Humidity $\ge$ $65%$ ($\text{Target}$).

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𝐀𝐁𝐎𝐔𝐓 𝐔𝐒

• Developed By AHSAN HABIB

• CEO and ADMIN of BANGLADESH CYBER 2.0