Fig. 2. Summary of the experimental and computational studies of the effects of device mass, modulus, tissue thickness, and signal frequency on measured mechano-acoustic responses.

Experimentally measured spectral power and simulation results associated with the mechano-acoustic response of a device mounted in an acrylic box placed on a tissue sample on a vibrational source at frequencies of 50 Hz (A), 100 Hz (B), and 200 Hz (C). (D) Comparison of measured (experiment) and computed (analytical) dependence of spectral power on mass. (E) Measured maximum signal amplitude recorded with a device mounted on the neck as the subject said the word “left,” as a function of the mass of the device. (F) Amplitude measured using a device in a rigid box and on a thin substrate of Ecoflex, as a function of spatial location of the added mass.