February 2012 Project – Update 1

February 14, 2012

I’ve been able to find some time to work on this month’s project and in the few hours I’ve been able to devote, it’s been pretty fruitful. Who uses the term “fruitful”? Whatever, it’s going well so far.

The steps that I outlined for myself were to:

  1. Combine all of my past sketched into one project
  2. Create some sort of visual feedback of live data
  3. Record that data and create something cool with it

Step 1 was a lot easier than I thought it would be. I sometimes forget how easy processing is to work with. I had sketches for calibrating the accelerometer, saving the accelerometer data, and reading and displaying the data. I just created a class for each of those and called their update/draw functions when needed and that was pretty much it. That was only an hour or two worth of work. But really, that just got me to ground level so that I could actually be productive.

The biggest challenge with working with an accelerometer is understanding what the data your getting actually means. Originally, I had it in my mind that the accelerometer was measuring the point in space that it was in and the acceleration between 2 points. That’s sort of true, but after thinking about it and reading up some more, I realized that it’s more about the acceleration among the axis’ then the actual points, since that’s arbitrary information. The next part of thinking through what kind of useful data I could get from the acclerometer was turning those seemingly random numbers into useful numbers. For each axis, I was getting numbers is a range of 225 to 435 or so, which does’t mean anything as they are. What do those number mean really? What you have to do is turn those numbers into something else that makes sense.  After going through some arduino forums posts, I found an equation that convert the numbers into a decimal that  to stand for gravitational force (acceleration) based on the voltage and sensitivity of the accelerometer. Or something like that. Luckily, that info was easy to find. After working this in, it made a huge difference.

From there, I plotted the x, y, and z force onto a 3d axis and started turning those numbers into velocity values so that I can draw with the accelerometer.

I’m doing something that’s slowing down my processing sketch like crazy, so that’s the next thing to figure out. Once that’s done, I have ot go in and refactor some code and refine my data saving and reading classes. I’ll then pass this sketch to the artists that I’m working with, Craig Damrauer, so that he can start playing with it and coming up with some ideas to turn this data into something beautiful.

In my next update, I hope to share some sort of video demo of my progress. Stay tuned.