文献类型：期刊文献

英文题名：EGaIn-enhanced PDMS dielectric composites for flexible tactile sensors with three-dimensional force sensing

作者：Wang, Zhiwen[1];Wang, Yuxin[1];Wang, Lei[1];Pang, Zhiwei[1];Lu, Zhaojin[1];Chen, Xin[1];Sha, Jin[1];Bai, Zhishan[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Shanghai 200237, Peoples R China

年份：2025

卷号：525

外文期刊名：CHEMICAL ENGINEERING JOURNAL

收录：;EI(收录号：20254519472401);WOS:【SCI-EXPANDED(收录号:WOS:001616203600021)】；

基金：The research was supported by the National Science Fund for Distinguished Young Scholars, China (No.22225804) and the National Natural Science Foundation of China, China (No.22408101) , Natural Science Foundation of Shanghai, China (No.25ZR1401085) , and Guizhou Provincial Science and Technology Support Program (Qiankehezhi [2025] General 091) .

语种：英文

外文关键词：Flexible capacitive sensor; Three-dimensional force sensing; EGaIn/PDMS composite; Surface modification; Anisotropic dielectric response

摘要：Flexible tactile sensors capable of detecting three-dimensional forces are critical for advanced applications in robotics, prosthetics, and human-machine interfaces. However, existing multilayer or isotropic composite designs often suffer from increased stiffness, poor conformability, and crosstalk between sensing channels. Here, we present a monolithic flexible sensor features a composite sensing layer comprising 6-acrylamidohexanoic acid (6-AHA) surface-modified eutectic gallium-indium (EGaIn) microdroplets, uniformly dispersed within a polydimethylsiloxane (PDMS) matrix. Surface modification enhances the dispersion of microdroplets and interfacial compatibility, thereby improving both the mechanical flexibility and dielectric performance of EGaIn/PDMS. Designed with four orthogonal arranged interdigital electrodes, the capacitive structure enables independent measurement of normal and tangential forces. Finite element simulations and experimental characterization reveal that deformation and reorientation of EGaIn microdroplets under external loading induce anisotropic dielectric responses and localized electric field redistribution, enabling effective decoupling of normal and tangential forces within a compact architecture. The sensor exhibits high sensitivity to both normal and tangential forces (similar to 0.085 %/N), acceptable response (<310 ms), low hysteresis, and excellent repeatability under cyclic loading. Although response speed and long-term reliability remain limited by matrix viscoelasticity, this work provides a scalable route for fabricating monolithic three-dimensional tactile sensors with high sensitivity and directional resolution, providing opportunities for applications in wearable electronics, robotic manipulation, and electronic skins.