Subhash Chandra

Abstract:

Wearable electronics are rapidly transforming healthcare monitoring, human–machine interaction, soft robotics, and personalized sensing systems. These applications require lightweight, flexible, and geometrically customizable circuitry that can conform to soft substrates while maintaining reliable electrical performance. However, the fabrication of such systems remains technically challenging. Conventional approaches such as direct ink writing and conductive ink deposition offer geometric freedom but typically suffer from low electrical conductivity and poor interfacial adhesion between the printed ink and polymer substrates. Laser-based structuring techniques provide improved resolution but require costly infrastructure and are not widely adaptable to flexible or soft materials. Cold spray–based metallization methods, although effective for rigid substrates, face significant limitations in deposition precision and struggle to achieve uniform, adherent coatings on polymeric materials—particularly when applied to soft and deformable systems intended for wearable use. To overcome these limitations, we present a first-of-its-kind filament-engineered strategy for fabricating wearable electronics through material extrusion (MEX) additive manufacturing. In this approach, a flexible TPU substrate is first printed to serve as the structural base. Conductive circuitry pathways are then fabricated using a specially developed dip coated filament designed to facilitate subsequent selective metallization. This engineered filament enables simplified post-processing, allowing conductive metal layers to form directly along printed pathways. The resulting wearable structures demonstrate high electrical conductivity, strong metal–polymer adhesion, dimensional precision in printed circuitry, and mechanical compatibility with flexible substrates. By integrating filament-level surface functionalization with multimaterial MEX printing, this method establishes a scalable, cost-effective, and customization-friendly route for manufacturing next-generation wearable electronic platforms.

Address:Professor, Dept. Of Mechanical Engineering, Jadavpur University, Kolkata. , India