Analog vibration spectrum sensor

In the area of mechanical vibration sensing piezoelectric polymers like PVDF have been of great research interests in recent years because of their mechanical flexibility and easy manufacturability. The charges developed in these materials due to mechanical deformation can be converted into electrical voltages which can be further processed for suitable applications. In this paper we propose a system which is capable of producing frequency spectrum of the incoming mechanical signal directly. The system consists of stretched PVDF ribbons each having a different length and hence a different resonant frequency. The ribbons are capable of detecting frequencies since they produce maximum voltage output when the incoming mechanical signal frequency matches its resonant frequency. The paper outlines the mathematical analyses and simulations performed to prove the concept.