You make my <3 flutter!


Geeks are very particular about their space, so what could be better than a mobile, wearable device that notes their heart rate when someone enters their space. Whether you're cool, calm and collected or get palpitations when someone enters your space, it's interesting to note how a particular person affects your physicality, whether that be geek love or geek annoyance. It's not quite your heart on your sleeve, but round your neck!

I'm very interested in how sensing technology can display vital signs and how this can be monitored with other tech to tell us how we're feeling.

I've hacked a Sensebridge Heart Spark pendant (which pulses my heartbeat on LEDs from a signal from my Polar gym heart rate monitor) with a proximity detector pendant (that I've made from an IR sensor, resistors, transistor and potentiometer) together to make a mood sensing piece of wearable technology. Three of the LEDs on the Heart Spark display my heart rate and three light up to show someone has entered my personal space.

Ideas for taking this project forward

The next step is to add a Lilypad Arduino x-Bee transmitter to the hack, so I can send the data to my laptop to graph the data from the two sensors to plot how many times during the day I get fluctuations in my heart rate when someone enters my space.

Estimated costs for taking this project forward

For the Heart Spark and all the components, it cost me just under £80 to build. Though if the components were bought in bulk it would be considerably cheaper.

About the data used for this project

The data will come from an algorithm that I write for the Atmega microcontroller that sits on the Heart Spark. The x-bee will wirelessly send it to my computer for graphing.

Project URL:

Twitter: @Rainycat

Created at


Flickr Photos

Hactivate: You make my <3 flutterHactivate: You make my <3 flutterHactivate: You make my <3 flutterHactivate: caek reward for hack coming alongHactivate: sewing the IR sensor onto stripboardHactivate: RS gonks have invaded my hack!

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