研究目的

To derive an analytical model of the electrostatic transduction of a CMUT with mechanically coupled plate actuators, considering the effect of the coupling geometry's mass on the dynamic deflection shape and its impact on the small signal electrostatic behavior.

研究成果

The presented model for the small signal electrostatics of a CMUT with mechanically coupled plate actuators accounts for differences between static and dynamic deflection shapes, showing reduced electrostatic stiffness and transformation factor compared to conventional models. Finite element simulations confirm the model's accuracy with less than 1.5% deviation in eigenfrequency reduction. Experimental results verify the electrostatic behavior with DC voltage-dependent amplitude.

研究不足

The model assumes uniform motion of the roof plate, neglects local stiffening of the actuator due to the pillar, and is not valid after the pull-in point due to changes in vibration behavior. Experimental results show deviations possibly due to non-uniform roof motion or small applied DC voltages.