Arduino Forum

Using Arduino => Audio => Topic started by: ggsxx1 on Dec 30, 2018, 12:11 am

Title: Building a chassis ear
Post by: ggsxx1 on Dec 30, 2018, 12:11 am
 Hi i'm building a chassis ear. It's an electret microphone that is attached to a metal clamp used to measure vibrations and noises.The first part is easy microphone and amplifier.

 Where i'm having trouble is finding information on Fast fourrier transform or FFT.

I would like to be able to view the signal, to see the frequencies and amplitude either on serial display or a screen.

Suggestions would be greatly appreciated.
Title: Re: Building a chassis ear
Post by: Grumpy_Mike on Dec 30, 2018, 12:57 am
This link should help:- http://wiki.openmusiclabs.com/wiki/ArduinoFFT (http://wiki.openmusiclabs.com/wiki/ArduinoFFT)
Title: Re: Building a chassis ear
Post by: MarkT on Dec 30, 2018, 02:07 pm
Hi i'm building a chassis ear. It's an electret microphone that is attached to a metal clamp used to measure vibrations and noises.The first part is easy microphone and amplifier.
To sense vibration effectively (and accurately) its best to use a specialized sensor, electrets couple to air
well, but not the mounting itself (electret diaphragms are very thin).

To sense vibration of a solid object you ideally want a transducer with a high mass armature that will
try to stay still through inertia as the mounting point vibrates.  Such a transducer will ignore ambient
noises in the air.  The kind of exciter used to drive flat panels of material like a speaker spring to mind
as a possible transducer to experiment with.
Title: Re: Building a chassis ear
Post by: ggsxx1 on Jan 12, 2019, 05:12 pm
I will use an electret disc which doesn't use air to make it vibrate. This is what is commonly used on the market right now.
Title: Re: Building a chassis ear
Post by: ggsxx1 on Jan 12, 2019, 05:17 pm
This link should help:- http://wiki.openmusiclabs.com/wiki/ArduinoFFT (http://wiki.openmusiclabs.com/wiki/ArduinoFFT)
Thanks a lot Gumpy!