Looking for a vibrational microphone

[ClareB]

Hi there,
I'm doing some research into vibrational microphones - I need a microphone that will measure the changing vibration/frequency of someone's body whilst I'm interviewing them, and to be able to translate/record the vibration/frequency as a sound, separate from the interview. Does anyone know which mic I need or even if it exists? I know there are vibrational mics available but can't seem to find the exact type for this and its quite urgent as I've been searching for quite some time now! Thanks in advance

 

[Khron]

What sort of frequency range are you interested in / expecting?