Microcontroller measures heart rate through fingertip

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Picture of Microcontroller measures heart rate through fingertip

Heart rate is a very vital health parameter that is directly related to the soundness of the human cardiovascular system. This project describes a technique of measuring the heart rate through a fingertip using a PIC microcontroller. While the heart is beating, it is actually pumping blood throughout the body, and that makes the blood volume inside the finger artery to change too. This fluctuation of blood can be detected through an optical sensing mechanism placed around the fingertip. The signal can be amplified further for the microcontroller to count the rate of fluctuation, which is actually the heart rate.

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Step 1: Sensor assembly

Picture of Sensor assembly
The sensor unit consists of an infrared light-emitting-diode (IR LED) and a photo diode, placed side by side, and the fingertip is placed over the sensor assembly, as shown below. The IR LED transmits an infrared light into the fingertip, a part of which is reflected back from the blood inside the finger arteries. The photo diode senses the portion of the light that is reflected back. The intensity of reflected light depends upon the blood volume inside the fingertip. So, every time the heart beats the amount of reflected infrared light changes, which can be detected by the photo diode. With a high gain amplifier, this little alteration in the amplitude of the reflected light can be converted into a pulse.
kflores1123 days ago

I tried to simulate the hex file in RealPic but I cant see any output. is there any other simulator that you can recommend? Thanks!

danyalr1 month ago

Can we use the same project to measure the bloodpressure as well? Kindly do respond as it s very urgent. Thankyou!

hey, i have tried several times but failed to achieve this. can u please help me out?? can u please send me all the details with the program codes?

if possible please send me on

Ramsha Asim1 month ago

ohkay.. so i made the above design but i want to use it ATMEGA MCU not PIC controller. Im giving the output to the ADC of the controller and it not working right.

Am i suppose to give the output of the conditioning circuit to the RX pin? Or to any other pin as a digital input?

Would you please guide me with that?

thank you :)

Can i get a components list for this project?
I ....
Can i get a components list for this project?
my email id is (
rajbex (author)  bhupender51112 months ago
Here's a revision of this project:
vesper990 rajbex2 months ago

hi sir i will finish the project but i have some problem the display read wrong number of pulses like 601 200 etc.....

please please help my about that

and thank you

vesper9902 months ago

hi please please help me for project the problem in the project some time get wrong display like 601 pulses on 7 segment and another 000 on the display please show me where the problem

thanks alot

azablan2 months ago

hi, can i make this project via stm32 micro-controller?

koruptx25 months ago
One question on diagram you write TO "a" , that means a from 7 segment display . and there are 2 "a" one is under the D1. nice project:)
koruptx25 months ago
Hi, what should i do to adapt this for an Arduino Uno
rajeev05115 months ago
can u please send me the list of components...
brancara6 months ago
What are the specifications of the ir diode and photo diode?
sde silva29 months ago
Hello, Can you help me with the BOQ of this project? I am going to do this for our mechatronic subject.
Thank you
rajbex (author)  sde silva29 months ago
See a revised version of this project over here:
rakesh4859 months ago
my mail id is
rakesh4859 months ago
plz mail me the complete detailed pdf as soon as possible, i want to do this as my mini project. plz help me...
vprinc39 months ago
I wanna do this project. Can you please give me a instruction of this project step by step or post this project step by step please...... I'm new here so I need your help.................
bkay hbo10 months ago
I want to do this project...can I have the list of materials / components and the document for this project?
email: thanks.
rajbex (author)  bkay hbo10 months ago
You can buy an assembled Easy Pulse sensor from here:
You can interface it with Arduino, PIC or any other microcontroller.
rajbex (author) 10 months ago
You can buy an assembled Easy Pulse sensor from here:
You can interface it with Arduino, PIC or any other microcontroller.
qquuiinn11 months ago
could you pull this off with an op amp and metal contacts instead?
qquuiinn11 months ago
could you pull this off with an op amp and metal contacts instead?
Phil B2 years ago
Some exercise machines and programs utilize heart rate during a workout to adjust intensity for the desired benefits. It would be great to add lengths of flexible wire between the sensor and the rest of the circuit so the sensor could be attached by spring clip to an ear lobe or to a fingertip for a continuous reading during exercise. Thank you for a very nice Instructable.
rajbex (author)  Phil B12 months ago
Hi Phil,
Here's a new look of this pulse meter. I just finished writing about it on my blog.
a au Phil B2 years ago
hello... if u have successfully designed ur heart beat sensor, plz help me in making it... i m also doing it for my engineering project...:( help me out.... if u have detailed information about ib then plz plz mail me at ""
will be thankful to u...
agupta5212 months ago
can we use atmega8 for the same. can u post the circuit for the same?
nithin36911 year ago
Hello, can i have the complete details of the project please, i need the list of components and the document. could some one help me out with this issue.

mque1 year ago
We couldn't find a 10- pin 3 digit display. We only have a 27- pin 3 digit CA display. How do we connect the pins to the PIC?
now if you make two heart rate monitors, you could make a game to see who can lower their heart rate the most
frederickp1 year ago
Hello, Could you send me a list of materials to my email please?
sasi bindu1 year ago
the sensor is not working properly.sometimes it is taking a little movement of finger also as a pulse.sometimes it is not even detecting blood to make use of it efficiently?please reply for this becoz i have done entire project.i need to rectify this problem
anika19931 year ago
please provide me the list of components used?
please provide me the list of components I want to work on this component
my ID is
please provide me the list of components used with it's values and specification ?
---Samarth Kumbhar
sasi bindu1 year ago
i built this circuit from micro controller part.i have given pulses from function generator with 3hz,5v to tocki pin.but the display is not showing anything.when i have pressed start button it is showing 000.but later it is not working.can i have any suggestion.
thanks my circuit is working by providing a delay of 2 seconds before if condition in the program.but i did n't get the exact is really a nice project.
bubblelogic2 years ago
Hello again, I forgot to mention, is th code written in source boost c, because that is what I will be using, for c programming.


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