…of course i was logging

Screen shot 2010-01-30 at 20.12.55I fractured my ankle in a hard snowboard crash a couple of weeks ago and of course I was data logging the accelerometer forces. I was using the iPhone app developed last fall for the seismi{c}ycling project; while riding the phone was in my jacket’s internal chest pocket.

A group from ITP was enjoying the bitter weather at Mount Snow, in West Dover, VT on our (now annual?) Snowbunnies trip. This crash was late in the day on a wide open trail. I accidentally disengaged my heelside edge for a moment, causing me to rotate slightly clockwise and slide laterally. Moments later, my heelside edge caught again, now on the downhill side, causing me to quickly flip backwards onto my head … thankfully I was wearing a helmet. After that I can’t recall what exactly happened, but I know that it involved a lot of tumbling which my right ankle just couldn’t weather.

The data was recorded at 10Hz and includes GPS coordinates, heading, estimated speed and altitude and the accelerometer values. I used a simple java / processing application to graph the log. In the video clip below I’ve applied low pass filtering to the raw acc data and used that to control a 3d box, representing my orientation during the crash.

The log file is included here in CSV format if anyone wants to check it out or make an awesome visualization of it! There is some weirdness at the beginning of the file…perhaps as Core Location was getting a GPS fix. [crash datalog]





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