Geometry Transfer Using Cross Sections for Sequential Mechanical-Electrostatic Simulation of Microstructured Flexible...

Predicting how microstructure dimensions affect the response of flexible capacitive pressure sensors can guide sensor design. Large deformation and contact, however, complicate the construction of dielectric and air domains from the deformed mechanical geometry. This study presents a geometry transfer method based on equivalent cross sections. The method uses the finite element software packages Abaqus 2023 and COMSOL Multiphysics 6.2 for mechanical and electrostatic analysis, respectively. The electrostatic domains are reconstructed from horizontal section areas of the deformed boundary, current polydimethylsiloxane layer thicknesses and microstructure height. The method was evaluated using two square frustum geometries and measurements from three independent devices. Five equivalent square sections yielded volume meshes and capacitance solutions for all 29 selected states of each geometry. For the baseline geometry, capacitance differed from a 17-section reference by at most 0.1092% across four states spanning 0-411.85 kPa. Replacing equivalent squares with fitted contours of equal area changed capacitance by at most 0.04835%. A microscopy-guided geometry adjustment preserved the initial electrode separation and sidewall angle. Over 0-350 kPa, the adjustment reduced the root mean square error between the predicted relative capacitance response and the experimental mean from 0.0721 to 0.0292. The method provides a practical route from nonlinear deformation to capacitance prediction for microstructure design.