I’ve upgraded the first circuit with the potentiometers and the results look
promising. I used the Processing sketch that comes with the Arduino to make
a graphic of my breathing activity. I’ve tagged the different regions in the
graph so it’s easy to follow the movement of the breath. Btw the circuit is
constructed in such a way that the resistance decreases when the sensor is
stretched (breathing in.)
For this experiment I put the belt with the sensor rather tight around my
waist and I wasn’t talking. Talking makes the ‘not breathing’ part more
ragged but you can still clearly see when I’m breathing in and out.
Tag Archives: graph
Animated
Yesterday I continued working on the heart-beat graph. I’ve managed to animate it. The speed of the animations varies with your cursor position. The speed ranges from 1000 milliseconds to 1 millisecond. When the animation goes faster the string of dots seems to be alive, like some snake like creature. Fascinating to watch.
The dots are 15 pixels apart. For my test file with 20 hours of data the heart-beat graph has a width of 107374 pixels! Flash is pretty powerful to caculate this image in less than a second, amazing.
As for the data collection. I’ve slept a night with the belt fastened by broad strips of medical tape. It worked till 7 am, which is an improvement but still not perfect. I’ve posted the question at a user group and hope to get some tips for improving this.
ps. My lowest heart-rate was 34 bpm this night! The lowest I ever measured.
Happy

prototype of the first heart-beat graph
I’ve managed to code my first heart-rate graphic. And it’s CUTE!
By looping through the big data file I can isolate the heart-beats, take the different values to draw lines and put in the dots at the right coordinates. The next step is to draw a big graph in Flash and move it to the right at certain intervals (500 milliseconds for example). Now it still is a drawing that is animated from left to right. It disappears from view after a while, as you can see in the picture.
