Design, modeling, fabrication and characterization of a MEMS acceleration sensor for acoustic emission testing

Abstract

This paper reports on the development of a capacitive MEMS acceleration sensor applicable for acoustic emission testing. As a key feature, the sensor consists of two resonators with different resonance frequencies (90 kHz and 110 kHz) and an opposing electrode arrangement improving the rejection of disturbing low-frequency mechanical vibrations. In order to characterize the frequency response of the sensor a test bench was developed which allows to mechanically excite the sensor up to frequencies of 250 kHz using a piezoelectric shaker. The applicability of the sensor to acoustic emission testing is demonstrated by applying it to experimental tests such as wave speed measurement and source localization.