Enabling Tunability of a MEMS Sensor with a Geometric Nonlinearity1

The properties of a thermally actuated MEMS sensor with a geometric nonlinearity are investigated. This MEMS sensor is a potential candidate to construct a neuromorphic acoustic sensor to mimic the functionality of the cochlea by controlling an Andronov-Hopf bifurcation with the thermal actuator. The resonance frequency of this sensor becomes tunable by introducing a geometric nonlinearity. With this nonlinearity the frequency response of the neuromorphic acoustic sensor is controllable by assigning a DC-voltage. Moreover, the effects of harmonic excitation on the MEMS sensors are analyzed. Here, the critical points of saddle-node bifurcations are approximated and the movement of the frequency with respect to a harmonic excitation is discussed. The results are illustrated by numerical simulations.