Novel Haptic Electronic Yarn for Wearable Textiles: Vibrotactile Feedback via Knitted Channels for Skin-Based Communication

Abstract This work introduces a novel electronic yarn (E-yarn) capable of delivering controlled vibrotactile feedback, offering a seamless haptic integration technique into wearable textiles. By embedding miniature vibrotactile motors at the yarn level and employing robust encapsulation techniques, the design ensures durability and compatibility with everyday wear. Prototypes, including a knitted glove incorporating these haptic E-yarns, demonstrated sustained functionality over 20 wash cycles with minimal resistance change (< 1%), and first signs of failure at cycle 23. Performance evaluation using a custom test rig revealed strong correlations between compression forces and vibrotactile output, with frequency and amplitude influenced by textile structure and dynamic loading. Haptic E-yarns achieved an average vibration of 282.6 ± 33.4 Hz at 0.34 ± 0.2 ms ⁻² , with only 1–5% frequency variation and up to 40% amplitude increase post-integration to wearables. This technology enables reliable haptic feedback within textiles, paving the way for future applications in assistive communication and interactive wearables.