IoT-Based Real-Time Temperature & Humidity Monitoring System

Hardware Setup

Figure: Arduino-based temperature and humidity monitoring setup

Overview

This project implements an IoT-based system to monitor temperature and humidity in real time using Arduino and Python. Sensor data is collected, transmitted via serial communication, and sent to a server through HTTP requests.

System Architecture

Sensor (DHT11) → Arduino Uno → Serial Communication → Python Client → Flask Server

Features

Real-time temperature and humidity monitoring
Dual output interfaces:
- LCD display (hardware)
- Serial monitor (laptop)
Data transmission to server using REST API (HTTP POST)
Continuous data streaming pipeline
Modular system design (hardware + software integration)

Components Used

Arduino Uno
DHT11 Temperature & Humidity Sensor
16x2 LCD Display (I2C)
Breadboard & jumper wires
Computer (for serial communication and server)

Project Structure

iot-temperature-humidity-monitor/
│
├── code/
│   └── main/
│       └── main.ino
│
├── client/
│   └── serial_to_server.py
│
├── server/
│   └── app.py
│
├── images/
│   └── setup.jpg
│
├── README.md
├── requirements.txt

How It Works

DHT11 sensor reads temperature and humidity
Arduino processes the data and displays it on LCD
Arduino sends formatted data via Serial
Python client reads serial data using pyserial
Data is parsed and sent to Flask server via HTTP POST
Flask server receives and logs the data

Tech Stack

Arduino (C++)
Python
- Flask
- pyserial
- requests

Setup Instructions

1. Upload Arduino Code

Open Arduino IDE
Upload main.ino to Arduino Uno

2. Install Python Dependencies

pip install -r requirements.txt

3. Run Flask Server

python server/app.py

4. Run Client Script

python client/serial_to_server.py

5. Important Notes

Ensure Arduino is connected via USB
Use correct COM port in client script
Close Arduino Serial Monitor before running Python script

Future Improvements

Cloud integration (AWS / Firebase)
Web dashboard for visualization
Real-time graph plotting
Database storage (SQLite / MongoDB)
Upgrade to DHT22 for higher accuracy

Key Learning Outcomes

Serial communication between hardware and software
Data pipeline design and implementation
REST API integration
IoT system architecture fundamentals