Analytical capacitive sensor sensitivity distribution and applications

Robustness, versatility, high level of performance and low cost are some of the characteristics that make capacitive sensors well suited for industrial applications. They consist only in electrodes and measurement circuits but give access to position information and/or material properties. The design of capacitive sensors is however not so obvious so that simple structures are generally used to avoid time-consuming calculations and developments. We propose an analytical method to determine the sensitivity distribution of any capacitive sensor structure. This method makes it possible to rapidly optimize structures in order to increase the sensor sensitivity to one parameter or to render it less sensitive to another. Comparisons between the sensitivity map of known sensors and those obtained with the analytical method proposed in this paper show a great accordance.

[1]  J. B. Hasted,et al.  Liquid Water: Dielectric Properties , 1972 .

[2]  Robert Puers,et al.  Capacitive sensors: When and how to use them☆ , 1993 .

[3]  J. Kornet,et al.  Long-term tests of capacitive humidity sensors , 1994 .

[4]  David Galipeau,et al.  A study of low-cost sensors for measuring low relative humidity , 1995 .

[5]  Denis Donlagic,et al.  Sensor for high-air-humidity measurement , 1996 .

[6]  Wuqiang Yang,et al.  Sensitivity distributions of capacitance tomography sensors with parallel field excitation , 1997 .

[7]  Nils Karlsson,et al.  Capacitive detection of humans for safety in industry - a numerical and experimental investigation , 1998 .

[8]  H. Elgamel,et al.  A simple and efficient technique for the simulation of capacitive pressure transducers , 1999 .

[9]  Tomasz Dyakowski,et al.  RAPID COMMUNICATION: A capacitance probe for interface detection in oil and gas extraction plant , 1999 .

[10]  Thierry Ditchi,et al.  Influence of divergent electric fields on space-charge distribution measurements by elastic methods , 2000 .

[11]  Pentti Mattila,et al.  Capacitive ultrasonic transducer with net backplate , 2000 .

[12]  Tomasz Dyakowski,et al.  Application of electrical capacitance tomography for measurement of gas-solids flow characteristics in a pneumatic conveying system , 2001 .

[13]  Radosław Wajman,et al.  Electrical capacitance tomography: image reconstruction along electrical field lines , 2001 .

[14]  J. Crassous,et al.  A new capacitive sensor for displacement measurement in a surface force apparatus , 2001 .

[15]  A. Kovacs,et al.  Analytical Calculation of Sensitivity for Capacitive Pressure Transducers , 2002 .

[16]  Thierry Ditchi,et al.  Distance-Corrected Capacitive Sensors for Advanced Air Bag Applications , 2003 .

[17]  A. Dehe,et al.  AC transfer function of electrostatic capacitive sensors based on the 1-D equivalent model: application to silicon microphones , 2003 .

[18]  Dong-Chul Han,et al.  Optimal multi-segment cylindrical capacitive sensor , 2003 .

[19]  M. Liess.  A description of properties and errors of simple and stacked sensors , 2003 .

[20]  Thierry Ditchi,et al.  Morphological capacitive sensors for air bag applications , 2003 .

[21]  A. Jaworek,et al.  Gas/liquid ratio measurements by rf resonance capacitance sensor , 2004 .

[22]  Dong-Chul Han,et al.  Nonlinear analysis of cylindrical capacitive sensor , 2005 .

[23]  M. Zahn,et al.  Modeling of spatially periodic dielectric sensors in the presence of a top ground plane bounding the test dielectric , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.