Those who know me, know I love sensors, and doing things with sensors. I've published many posts on accessing the various sensors on the Microsoft Band: Accelerometer & Gyroscope, Ultraviolet, Skin Temperature, and Galvanic Skin Response. One subject that I haven't gotten to is the heart rate sensor. I've also started to publish a few IoT posts. For this post, I thought it would be fun to integrate the Band's heart rate sensor with a Particle Photon so you can visualize your heart rate with an RGB LED. The LED pulses at the same rate as your heart and will shift its color from blue (for low rates) to red (for high rates).
In order to access the heart rate sensor on the band, I’m following the same project format as in my previous posts listed above, which are all based upon the Windows Phone. For other phones and devices, you can get what you need on the Band developer site.
To send the heart rate value and control the RGB LED with a Photon, I’ll use the same hardware, software, and firmware as my recent post on Controlling an RGB LED on a Photon with a UWA Color Picker. I did need to update the firmware to accommodate the pulsing of the LED to match the heart rate. I also needed to update the software to send the heart rate along with the color info.
The resulting project demonstrated that it was possible to tie together these diverse devices into a potentially useful system. I found that, while manually taking my own pulse, the pulsing of the LED did indeed follow the same rate. Of course the LED pulse wasn’t in sync with my heart beat, but it was evident that the rates did match. How might this be used? Not sure, but I found it to be cool.