This Project aims in designing an automatic fan speed control system using PIR and temperature sensor and it also indicates the temperature value and fan speed on the LCD (Liquid Crystal Display). The fan is controlled only when a person is presents. The system will get the temperature from the temperature sensor and person detection using PIR sensor. Based on the temperature value it will control the fan speed accordingly when a person is presents. The System is fully controlled by the microcontroller. Temperature Monitoring systems are in huge requirement and we definitely can find their advantages in many industrial sectors and also in residential sector. We can find many kinds of temperature monitoring systems for different uses but the major challenge is to design a very simple, user-friendly and cost-effective system. Employing this method we can save the energy. The main controlling device of the project is Arduino UNO microcontroller. Temperature sensor, PIR sensor, LCD display, Bluetooth, transistor through DC Fan is fed to the microcontroller. According to the received temperature values and human presents, microcontroller will generate the PWM signals to the transistor to control the fan speed. Transistor acts as a regulator and hence speed of the fan is controlled. Microcontroller will monitor the temperature value and fan speed on LCD and also it will send to the user Bluetooth mobile application wirelessly. By using Bluetooth mobile application user will control the fan wirelessly. To achieve this task microcontroller loaded program written in embedded C Language.            

The major objectives of this system are:  

1. Automatic controlling of fan speed based on temperature.
2. Monitoring temperature and fan speed on LCD.
3. PIR based human detection and fan controlling.
4. Wireless monitoring of temperature and fan speed using Bluetooth technology.

         

The main building blocks of the project are:

1. Adapter Power Supply.
2. Arduino UNO Microcontroller.
3. Temperature sensor.
4. PIR sensor.
5. Bluetooth Module.
6. LCD display.
7. Transistor with DC Fan.

       

Software’s used:

1. Arduino IDE studio compiler.
2. Express SCH for Circuit Design.
3. Embedded C language.

           

Block Diagram:          

video: