Feedback MP3 Player and Activity Logger

Steve (aka Polymythic) created a Motion Feedback MP3 Player that plays music tracks at varying volume depending on the level of activity the system detects. The concept is to encourage more activity by creating a feedback loop between the volume of music and the level of your activity.

Motion Feedback MP3 Player

Motion Feedback MP3 Player

Motion is detected with a Parallax PIR Sensor. When motion is detected, the output pin of the sensor goes high. That out is monitored by the ioBridge IO-204. With or without a network connection, the IO-204 sets the volume of a DIY MP3 Trigger board from SparkFun. The volume is controlled by sending serial strings to the MP3 Trigger. Steve took advantage of the new Onboard Rules that turn the IO-204 into a standalone controller. When the IO-204 is connected to the Internet, the IO-204 also data logs his activity by sending it to the ioBridge data logging service in the cloud.

To learn more about how to make your own, visit Instructables and or YouTube. The project also is posted on Engadget and UberGizmo. Well done, Steve.


  1. Jordan says:

    This project is great… 🙂 Make this for runners…

  2. Samuel says:

    This would be a cool upgrade…maybe an iPod nano strapped to the arm…if it had an accelerometer that would be a way to detect motion. Great idea!

  3. ModModder says:

    When do you think a product will come out like this? You could use the accelerometer of a phone and control the volume proportional to g-force. Cool concept!