Broad detection range of flexible capacitive sensor with 3D printed interwoven hollow dual-structured dielectric layer

Abstract

Flexible pressure sensors play a pivotal role in the realm of smart wearable devices. Despite extensive exploration into methods for creating dielectric layers with microstructures, the associated complex fabrication processes and challenges of mass production remain pressing issues. This study introduces an innovative approach to crafting flexible capacitive pressure sensors. We utilize interwoven hollow dual-structured materials as the dielectric layer of the sensor through photocurable 3D printing, simplifying production steps and achieving the one-piece molding of the dielectric layer. Due to the abundant air within the dielectric layer and the inherent resilience of the flexible photocurable material, the resulting sensors exhibit exceptional responsiveness and durability, with a measurement range extending to at least 600 kPa. Furthermore, we evaluate the effectiveness of sensors employing the interwoven hollow structure by comparing them with other structural designs. The dual-structured sensors demonstrate a sensitivity approximately ten times higher than that of flat structures, particularly in the wide pressure range of 200–600 kPa. In practical applications, our designed sensors can detect various human activities, such as finger presses, wrist bending, and object grasping. They are also well-suited for monitoring plantar pressure distribution, signifying their potential for integration into smart wearable devices, health monitoring systems, and human-computer interaction interfaces.