#64 Lie Detector! Heartbeat Pulse Monitor KY039 - It's life Jim, but not as we know it

[@CooperDuper3000]

Oh nice, that is pretty neat! Thank you for your informative video on that kind of sensor!

[@RalphBacon]

Yes it worked a lot better than i thought it might, given its low price. Glad you liked the video and thanks for posting.

[@draalchemist]

Thank you for the code and explanation. I'm learning about arduino and sensors. Your material is really good!!!

[@RalphBacon]

Glad it was helpful!

[@abedbug9953]

These remind me of the sensors you used to get many years ago for gym equipment where you would clip a sensor on your earlobe (bit like a small peg with a wire running from it) and is connected to the running machine. I think they work in the same principle as shining a torch through the back of your hand (as we've all done as kids), you see a red glow from the blood. When the heart beats, there is temporarily more blood, so in theory less light should pass through. Fun and quirky - yes but probably a bit too random for olympians! Enjoy your vids keep up the good work, Alan

[@RalphBacon]

Hi Alan, yes i think you're spot on there. I'm amazed that the device can detect such a tiny difference in blood flow but it does it very well. Thanks for your supporting words, it's good to hear from my Arduinite subscribers.

[@abedbug9953]

Cheers Ralph, when are we going to see the mystery LED ring build

[@RalphBacon]

Ah well, first I must return from my annual vacation ( I'm typing this on my phone 5,000 miles away from my home on another continent, yes my professionalism knows no bounds) then it's Xmas and New Year so maybe the backend of this year or early next year. Before going on vacation I did experiment a bit with the LED ring and I'm impressed with its capabilities (or the library we're using, anyway). So stay tuned, did you proffer a guess to what it might be?

[@abedbug9953]

Ralph S Bacon I had a guess on the comments to the led ring video, thanks for reply

[@jeanclaude8857]

Thank you for the code, Kind regards

[@RalphBacon]

You're welcome, Jean.

[@RazoQuinnvanBerkel]

Amazing! It took quite a while to find something that works. Thank you! You've got a new subscriber :D

[@RalphBacon]

I'm very glad it worked for you, and thank you for subscribing, appreciated!

[@TheAppleProfessional725]

Where can I find the parts for this item and how do I construct it? Is it on the website you linked below?

[@RalphBacon]

This was a self contained module, but I can't remember where I got it from. It was probably this one: www.banggood.com/KY-039-Finger-Detection-Heartbeat-Sensor-Module-Finger-Detect-Measurement-For-Arduino-p-1540574.html?p=FQ040729393382015118&

[@Roy_Tellason]

@@RalphBacon This module was also included in the "37 sensors" I got from banggood...

[@caiobrandao1655]

I tried here, but I think there's something wrong, he starts before I put my finger, what do you use to stop it? sorry for my english.

[@RalphBacon]

Ola Caio, tudo bem? Ensure that there is no light from, say, a nearby lamp (or the sun) shining on the infrared detector. To fully test it, try it in a darkened room. Does it still beep before you put your finger in the gap? Try putting a small capacitor (say 47µF) across the power supply on the device too. Let me know if you succeed!

[@Richie_]

Nice one. Hard to find a code that worked.

[@RalphBacon]

Did it work? My heartrate certainly went up as I tested all this out but all was good in the end!

[@Richie_]

@@RalphBacon it sure did. I'm about to upload a small clip. Thanks.

[@Richie_]

@@RalphBacon kzbin.info/www/bejne/i5a8oqudoqmhhZI

[@RalphBacon]

Yes, that video definitely tells me you have a beating heart!

[@TheAppleProfessional725]

How do you know if someone’s lying?

[@RalphBacon]

Well, they look shifty, shuffle their feet, don't look you in they eye... Oh! You mean with this detector? Faster heartbeat I guess!

[@TheAppleProfessional725]

Thank you so much! I am deciding to make this for a project and I needed some further details.

[@TheAppleProfessional725]

Thank you so much! I am deciding to make this for a project and I needed some further details.

[@TheAppleProfessional725]

Is this very accurate?

[@RalphBacon]

Not for medical use! Just an experimenters module. BUt as you saw it followed my heart beat OK. Most of the time.

[@TheAppleProfessional725]

Thank you so much! I needed further details becuase I was going to do this for a project

[@TheAppleProfessional725]

What does it sense?

[@RalphBacon]

It senses the slight difference in finger light transmission, if I recall correctly.

[@roberteliassen5020]

Forefinger up! Luckily you didn't use the middle finger. :-)

[@RalphBacon]

I don't know what you can possibly mean, Robert! How very dare you! (Now there's a very British catchphrase for you). This little device was a lot of fun to play with, and worked *much better* than I thought it would. It would make a really good "lie detector" circuit with a built in beeper loud enough to be heard at a Christmas party along with lots of Neopixels. For fun only though, I suspect, I would not like to rely on it to detect whether I'm still alive or not. Good to hear from you.

[@roberteliassen5020]

Thanks for the catchphrase. It sounds rather posh to me, but who am I to judge? ;-)