The heart rate monitor is an embedded system based on 8085 intel microprocessor and an Infrared sensor designed with the help of the technique Photoplethosysmography. The person willing to test their heart rate will place their
finger on the sensor and their measured heart rate will display upon the 3 digits seven segment display.
The front side of the IR diode and photo transistor are exposed and the remaining parts are well isolated. When the finger tip is placed over the sensor the volumetric pulsing of the blood volume inside the finger tip due to heart beat varies the intensity of the reflected beam and this variation in intensity is according to the heart beat. When more light falls on the photo transistor it conducts more, its collector current increases and so its collector voltage decreases. When less light falls on the photo transistor it conducts less, its collector current decreases and so its collector voltage decreases. This variation in the collector voltage will be proportional to the heart rate.
Their project was incomplete, hence you would not find project images or any video here.