Publication Date:
2013-09-07
Description:
We discuss the fabrication and performance of an all-polymer, flexural plate wave gravimetric sensor using flexible, piezoelectric Polyvinylidene fluoride as the substrate and an inkjet-printed interdigital transducer (IDT) employing conductive poly(3, 4-ethylenedioxythiophene) poly(styrenesulfonate) to excite Lamb waves within the film. Lamb waves are measured both electronically, using a second IDT, and mapped directly using a scanning laser Doppler vibrometer. Pulsed wave excitation is utilized to isolate the weak acoustic signal from the electromagnetic crosstalk, enabling the measurement of relative changes in the resonant frequency, $Delta f/f_{0}$ , in response to added mass, $Delta m$ , to the sensing area. A gravimetric mass sensitivity equivalent to $Delta f/(f_{0}Delta m)=-153~{rm cm}^{2}/{rm g}$ is measured by mass loading the sensor with printed polymer layers. It is found that the low stiffness of the substrate contributes significantly to the response of the sensor, yielding a measured overall sensitivity of $Delta f/(f_{0}Delta m)=-83~{rm cm}^{2}/{rm g}$ .
Print ISSN:
1530-437X
Electronic ISSN:
1558-1748
Topics:
Electrical Engineering, Measurement and Control Technology
