Customized batch fabrication of highly sensitive thin capacitive soft sensors based on high dielectric constant composite polymers

Abstract

Soft capacitive sensors are essential for emerging technologies in soft robotics, wearable electronics, and human-machine interfaces. However, scalable, customizable, and cost-effective fabrication methods remain a challenge. In this work, we present a novel batch fabrication approach for producing thin, highly sensitive soft capacitive sensors using high-dielectric-constant composite elastomers. Our method enables the rapid production of large-area sensor sheets that can be precisely patterned into arbitrary geometries using laser cutting, eliminating the need for complex microstructuring or lithography. These sensors are composed entirely of soft layers, including carbon nanofiber-based electrodes and dielectric layers enhanced with barium titanate (BTO) or titanium dioxide (TiO2). We demonstrate a gauge factor of 2.83 and a sensitivity of 0.55 kPa⁻¹, with low hysteresis and broad pressure range. Furthermore, we present the integration of these sensors into a tactile array for wearable pressure sensing, highlighting their potential in soft robotics and health monitoring systems. This work offers a scalable and versatile platform for next-generation soft sensing technologies