A Theoretical Study on an Elastic Polymer Thin Film-Based Capacitive Wind-Pressure Sensor

Abstract

This study is devoted to the design of an elastic polymer thin film-based capacitive wind-pressure sensor to meet the anticipated use for real-time monitoring of structural wind pressure in civil engineering. This sensor is composed of four basic units: lateral elastic deflection unit of a wind-driven circular polymer thin film, parallel plate capacitor with a movable circular electrode plate, spring-driven return unit of the movable electrode plate, and dielectric materials between electrode plates. The capacitance of the capacitor varies with the parallel move of the movable electrode plate which is first driven by the lateral elastic deflection of the wind-driven film and then is, after the wind pressure is reduced or eliminated, returned quickly by the drive springs. The closed-form solution for the contact problem between the wind-driven thin film and the spring-driven movable electrode plate is presented, and its reliability is proved by the experiment conducted. The numerical examples conducted show that it is workable that by using the numerical calibration based on the presented closed-form solution the proposed sensor is designed into a nonlinear sensor with larger pressure-monitoring range and faster response speed than the linear sensor usually based on experimental calibration.

Axisymmetric Large Deflection Elastic Analysis of Hollow Annular Membranes under Transverse Uniform Loading

“…Therefore, with the known c 0 and c 1 the value of d 0 can be determined by Equation (33), and the expression of W can also be determined. As for the expression of S t , with the known expression of S t , it can easily be determined by Equation (18).…”

“…A computational error in the power series solution which was presented by H. Hencky in 1915 [1] was subsequently corrected by Chien in 1948 [5] and Alekseev in 1953 [6], respectively. This solution is usually called Hencky solution, which is often cited in some studies of related issues [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. The closed-form solutions of the circular membrane problem under normal loading are available in a few cases in the existing literature [22][23][24].…”

Polymer Conductive Membrane-Based Non-Touch Mode Circular Capacitive Pressure Sensors: An Analytical Solution-Based Method for Design and Numerical Calibration

“…Thin films are widely used in many engineering and technical fields, and most of these have good elastic deformation ability and can exhibit large elastic deflection under lateral loading [ 1 , 2 , 3 , 4 , 5 , 6 ], which provides the possibility for designing and developing thin film elastic deflection-based devices [ 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. Among them, capacitive pressure sensors are a good example of physical quantity (pressure) detection by deflection measurement.…”

Polymer Conductive Membrane-Based Circular Capacitive Pressure Sensors from Non-Touch Mode of Operation to Touch Mode of Operation: An Analytical Solution-Based Method for Design and Numerical Calibration

“…Membrane structures, which are often characterized by large flexibility and thus endure large deformation under external loads [1][2][3][4][5][6], are widely applied to many engineering and technical fields [7][8][9]. In particular, the flexibility of membranes leads to the possibility of the design and development of elastic deflection-based devices [10][11][12][13][14][15][16][17]. Among these devices, capacitive pressure sensors are a representative example of physical quantity detection (pressure) by deflection measurement.…”