Automatic Fan Speed Control System

Arduino UNO C++ DHT11 Sensor PWM L298N Motor Driver 16x2 LCD (I2C)

Project Overview

This embedded systems project is an automatic fan speed controller that intelligently adjusts a DC fan's speed in response to changes in ambient temperature[cite: 30]. The system is orchestrated by an Arduino UNO board, which acts as the central processing unit. This project provides a practical, energy-efficient solution for automated climate control in a small environment.

Key Components & Functionality

Real-Time Temperature Sensing: A DHT11 sensor is used to continuously capture real-time temperature data from the environment.
PWM Speed Control: The Arduino processes the sensor data and generates precise Pulse Width Modulation (PWM) signals to vary the voltage supplied to the fan, thus controlling its speed.
Motor Driver Integration: An L298N or L293D motor driver is used to safely interface with the DC fan motor, providing the necessary current to drive it effectively.
Live Data Display: A 16x2 LCD, connected via an I2C interface to save pins, displays the current temperature and fan speed, providing real-time feedback to the user.

Technical Insights

This project was an excellent exercise in hardware-software co-design. The most challenging aspect was calibrating the relationship between the temperature readings and the corresponding PWM duty cycles to create a smooth, responsive fan speed curve. It provided hands-on experience with sensor data acquisition, signal processing on a microcontroller, and controlling actuators. This practical application solidified my understanding of how embedded systems interact with the physical world to perform automated tasks.