Bio-inspired hybrid composite fabrication 3D-printing approach for multifunctional flexible wearable sensors applications

Abstract

A bio-inspired, hybrid, multifunctional flexible sensor is developed for wearable applications. The hybrid sensor is fabricated using Fused Deposition Modeling (FDM) 3D printing and incorporates significant technical innovations. This sensor integrates a thermoplastic polyurethane (TPU-base core body) filament, graphene, and Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) PEDOT: PSS made-composite, utilizing a novel dip-coating technique to create high-aspect-ratio channels. Critically, we have developed a new method to compensate for drooping in bridging layers during the FDM printing process, a significant challenge in achieving precise microstructures. Demonstrating its potential for strain, temperature, pressure, and health monitoring. Results exhibit a high gauge factor (GF) of ≈4033.2 at 30 % tensile strain, detect strains as low as 0.01 %, and achieve a stretchability of 250 %. Furthermore, it demonstrates sensitivity to pressures ranging (max 150 %, mini 10 Pa), dynamic stretching (at 2, 6, 9, 10, 18, 21 mm), and thermal performance (0–90 °C). Subsequently, we propose on-site monitoring; the sensor’s ability to detect subtle and vigorous human motions is highlighted, suggesting its suitability for bodily deformations including subtle movements. This approach, incorporating these key fabrication innovations, paves the way for advanced wearable sensors capable of detecting a wide range of human motions for diverse healthcare applications.