Research On Pressure Displacement Sensitive Element Based On Conductive Polymer Composites

Composite sensor is a new sensor that is a new model with a broad application prospects.Currently,the most electrode of composite sensor remains conductive metal,which leads to the composite sensor that still has some rigidity.This thesis first studies the electrode of the flexible pressure displacement sensor made up of the composite and the influence to the electrical characteristics of the flexible pressure displacement sensor caused by the mass ratio of composite,the plus excitation frequency,the area of composite.The main contents of this thesis include the following items:(1)Preparation of composite sensor,the area is 2cm×2cm,3cm×3cm and 5cm×5cm,the thickness is 3mm,the mass ratio ranges from 0.01 to 0.17.(2)The influence of composite mass ratio,plus excitation frequency,the composite area for the flexible pressure displacement sensor displacement characteristics was analyzed,the"normalized impedance-Shift" and "normalized capacitance displacement" fitting formula was derivated.The result of experiments shows that the up and down two plates of composite are the same quality,the normalized impedance sensitivity is the largest.when the area of the composite material is bigger,the greater of the composite mass ratio can generate the normalized sensitivity to the maximum.(3)The influence of composite mass ratio,plus excitation frequency,the composite area to the flexible pressure displacement sensor pressure characteristics was analyzed.When the quality ratio of the up and down two plates are the same,the plus excitation frequency is 100kHz the noise is lower.(4)The thesis establishes the equivalent circuit model of composite,the core processor with STM32F103ZET6 and makes the displacement sensor probewith used the high sensitivity,gathers the voltage of the front-end circuit by means of the module of analog-to-digital.Finally,then the date is sent to PC through a serial port for saving and is shown the displacement.