F. Ahmed, C. Kwon, A. Mills
North Carolina State University,
United States
Keywords: sinusoidal interconnects, woven e-textiles, electromechanical performance, multi-directional weaving
Summary:
Electronic textiles (e-textiles) are fibers, yarns, or fabrics that integrate at least one electronic component. Despite extensive research, most e-textile systems remain at low Technology Readiness Levels (TRLs) and low Manufacturing Readiness Levels (MRLs), underscoring the barriers to commercial-scale production. A key challenge is the reliable routing of interconnects, which transmit power, data, or signals and strongly influence mechanical and electrical performance. Interconnect geometry also plays an important role, as meandering paths offer improved stretchability and reduced cracking compared to straight lines. While meandering printed interconnects have been explored, yarn-based sinusoidal interconnects integrated directly into woven structures using commercially available looms remain largely underexplored. Advancing this area is important for raising TRLs, MRLs, and supporting scalable manufacturing. This research investigates how geometric parameters of a sinusoidal interconnect influence its electromechanical behavior. Five sinusoidal variations are being designed in MUCAD by varying the amplitude (5, 10, 15, 20, and 25 picks per repeat) while keeping the wavelength and conductive trace width constant. The designs are transferred to a Jakob Muller narrow-fabric loom equipped with a multi-directional weaving (MDW) attachment. The base fabric is woven using non-conductive yarns, while the conductive threads are inserted as programmed inlay wefts. Ends per inch (EPI), picks per inch (PPI), and sample dimensions remain constant, and five replicates of each variation are produced. Following fabrication, the initial DC resistance of each interconnect will be measured using a four-wire configuration. Electromechanical performance will be evaluated using tensile and cyclic tests, with electrical resistance recorded continuously to generate resistance-strain and resistance-cycle data. A digital microscope will be used to examine surface topology and document any crack initiation during deformation. Drape behavior will be characterized using the Cusick drape tester to provide a comparative measure of textile flexibility across the different sinusoidal variations. The results will be used to establish a clear relationship between the sinusoidal wavelength and the interconnect’s electromechanical performance and durability. Future efforts will use these findings to guide the design of an integrated woven prototyping system.