Highly Integrated Fibers and Textiles for Sensing and Actuation via Thermal Drawing

The integration of sensing and actuation within fibers and fabrics is at the heart of the technological developments for smart and e-textiles. Several approaches exist for functionalization via a direct and selective coating of the already made fiber and fabric. An alternative approach relies on thermally drawing a fiber from a preform that already contains the desired functional materials within a cladding. This approach enables to realize fiber-integrated devices with complex architectures and functionalities, at the scalability traditionally associated with optical fibers. Until recently however, the cladding materials have been made out of rigid thermoplastic or glasses that could not respond to most mechanical external stimuli. Moreover, actuation of such advanced fibers had not been demonstrated. In this presentation, we will present the latest developments in the multi-material functional fiber field and show in particular how we can provide fibers with novel structures and materials that can sense a variety of stimulations, while at the same time being mechanically actuated, for advanced diagnostic and therapeutic tools (Leber et. al., Advanced Science 2204016, 2023). We will in particular show the materials selection criteria, and processes at play to integrate polymer composites, liquid metal, optical fibers, piezo-resistive or piezoelectric materials, as well as hollow channels, at prescribed positions and of arbitrary size within thin and soft elastomeric fibers. We will show examples of highly soft functional catheter-like fiber systems, advanced fibers for drug delivery, as well as electronic fibers for strain or pressure sensing that can be integrated into textiles for large area mapping. With just a few connections at the fiber ends, we will show how a single fiber can functionalize an entire area in a robust way, paving the way towards novel opportunities for advanced yet simple and affordable smart textiles for health care applications. Adding Magnetic composites, we will show how advanced and soft fibers can be actuated magnetically (Banerjee et. al., Advanced Materials 2212202, 2023). Integrating such fibers into textiles, we will show examples of applications where soft textiles can be magnetically actuated, paving the way towards novel soft prosthesis.