I’m experimenting with a prototypical bio-sensing device (described here) I built with the precious help of Dorkbot ALBA at the Edinburgh Hacklab. Although at the moment sensor is quite rough it is already capable of capturing muscles sounds.
As the use of free, open source tools is an integral part of the methodology of this research, I’m currently using the awesome Ardour2 to monitor, record and analyse muscles sounds.
The first problem I encountered was the conductive capability of human skin; when the metal case of the microphone directly touches the skin, body becomes a huge antenna attracting all electromagnetic waves floating around. I’m now trying different ways of shielding the sensor and this helps me to better understand how muscle vibrations are transmitted outside of the body and through the air.
Below you can listen to a couple of short clips of my heartbeat and arm voluntary contractions recorded with the MMG sensor. Audio files are raw, i.e. no processing has been applied to the original sound, their frequency is extremely low and it might not be immediately audible; you will possibly need to turn up the volume of your speakers or wear a pair of headphones.
Voluntary arm contractions
(sound like a low rumble, or a far thunder; clicks are caused by crackles of my bones)
At this early development stage the MMG sensor capabilities seem quite promising, I can’t wait to plug the sensor into Pure Data and start trying some real time processing.