The temporal modulation material is investigated to be used as lightweight sound isolation material. This smart composite material consists of a lightweight structure attached with shunted piezoelectric ceramic (PZT) patches. The shunt circuits are connected to the two poles of PZT patches to act as some local electrical resonators to improve the sound isolation. The circuit is composed of operational amplifiers and passive analog circuit elements, so the system is always stable, and the power consumption is low. The metal-oxide-semiconductor field-effect-transistor (MOSFET) is added in the shunt circuit connected to the PZT patches, so the time sequence of the working circuit is controlled with the MOSFET devices in each resonant shunt. The motivation of this study is to improve the sound isolation in the low-to-middle frequency range. The temporal modulation material proposed in this study has many potential applications in environmental acoustics, precise instrument, automotive sector, and aerospace technologies.
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