This is a simple embedded system project for college student and hobbyist. In this we use interrupt of Microcontroller Atmega328/8. In this project IR sensor is used which send a pulse after every rotation of motor and Arduino count these pulses and make a calibration for RPM and give output to LCD.
we all are well known about IR Sensor, it gives logical high when sensor is in front of white color and logical low when in front of Black color. in this project we are using a sample motor and we will measure the RPM of this motor.
A rounded disc is attached to axis of motor which is black in color and a white strip is fixed on the black disc. when IR Sensor is placed in front of disc it will give logical high when white part will come in front of sensor, every time it will give logical high for a bit of time.
Ir sensor is connected to microcontroller which is central processing unit, it count the no of pulses for every one second and print on the LCD (16x2)