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Inspired by a photoresistor-based pulse sensor designed by MarkusB from Let’s Make Robots, MAKE’s Technical Editor Sean Michael Ragan set about to build the IR Pulse Sensor using infrared emitter and detector diodes. The latest addition to our beginner-friendly Weekend Projects series, the IR Pulse Sensor is a unique combination of hardware and software, and it’s a great all-around project for learning.

We’ll start with scoring and snapping a multipurpose PC board to fit the circuit’s footprint. Sand down the sharp corners and sides you don’t need to make a truly custom board.

We’ll use a standard cable clip as a finger cuff, so that your finger will easily rest upon the diodes in order to detect your pulse.

Some simple modifications to the LM324 op-amp IC will be done in combination with a simple circuit soldered to the PC board before moving on to the software.

rewp09pulsesensorpreview

Output from the pulse sensor will input on the A0 pin header on the Arduino, and raw data from the device can be seen using the software sketch provided on MAKE’s GitHub repository. Lastly, Processing will be used to visualize that data and render it as a pulse on your monitor.

Whether you consider yourself a soldering whiz and want to learn a bit more about the Arduino and Processing, or vice-versa, or if you simply want to dive in and learn software and hardware, the IR Pulse Sensor is a great project to get started with.

Watch the video below to see this project in action. It only takes a few hours to build and then you can use this project for novel applications. Some ideas include matching musical beats to your heartbeat, triggering other devices with a specific pulse rhythm, or simply turning that beat into an audible sound. If you modify this project be sure to document your process and send us a story about your build – you could be featured on the MAKE blog!

Nick Normal

Nick Normal

I’m an artist & maker. A lifelong biblioholic, and advocate for all-things geekathon. Home is Long Island City, Queens, which I consider the greatest place on Earth. 5-year former Resident of Flux Factory, co-organizer for World Maker Faire (NYC), and blogger all over the net. Howdy!


  • http://historyofcoins.org/ Deborah Rodriguez

    interesting… I am just wondering how important it is to have this.

  • finchi

    Hi,
    what kind of IR emitter and receiver did you use?
    I tried with a 950nm emitter and a receiver that ranges from 400-1100nm (peak at 980nm).
    However it doesn’t seem that the setup works for me.
    I doublechecked the circuit more than once and tested single parts of it.
    Meassuring
    the voltage directly after the IR receiver I can detect a change (value
    rises from about 88 – 95 on arduino analog read) if i lay my finger
    over the sensor.
    However beyond the transistor I get a value that “flickers” around 725, but can’t detect any noteable change.

  • Vasudev Bangera

    hello someone please guide me with the arduino configuration the drivers are not detected and i downloaded it from this site only please someone help i have to submit my project by this Monday & also connection of pin 4 & 11 please explain
    Please madam who explained please help :)

  • sabrina

    Hi,
    can i replace the earlobe or the finger tips bye the wriste ?I would realise a bracelet that mesures the heart beats .this is my mail , please answer me : chabani2sabrina@gmail.com
    tks

  • http://www.hermesbracelet.us.com/ Hermes Bracelet

    Crease the drawstring by 50 percent, printed aspect in, and stitch along the nation’s length.

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