LDV measurement of small nonlinearities in flat and curved membranes. A model for eardrum nonlinear acoustic behaviour
Faculty of Sciences. Physics
Melville :Amer inst physics
Measurements by Laser and Noncontact Techniques: Advances and Applications
AIP conference proceedings / American Institute of Physics. - New York
12th International AIVELA Conference on Vibration Measurements by Laser, and Noncontact Techniques - Advances and Applications, JUN 29-JUL 01, 2016, Ancona, ITALY
, 10 p.
University of Antwerp
Laser Doppler Vibrometry is an intrinsic highly linear measurement technique which makes it a great tool to measure extremely small nonlinearities in the vibration response of a system. Although the measurement technique is highly linear, other components in the experimental setup may introduce nonlinearities. An important source of artificially introduced nonlinearities is the speaker, which generates the stimulus. In this work, two correction methods to remove the effects of stimulus nonlinearity are investigated. Both correction methods were found to give similar results but have different pros and cons. The aim of this work is to investigate the importance of the conical shape of the eardrum as a source of nonlinearity in hearing. We present measurements on flat and indented membranes. The data shows that the curved membrane exhibit slightly higher levels of nonlinearity compared to the flat membrane.