Koji Tsukada

Braided cords (kumihimo) are a traditional Japanese textile craft combining flexibility, strength, and aesthetic beauty. While e-textile research has explored weaving, knitting, and embroidery as fabrication structures, braiding remains largely unexplored as a substrate for interactive textiles. We present KumihImO, a design and fabrication approach that integrates conductive and thermochromic threads into braided cords with both sensing and visual-output capabilities. We characterize how braiding configuration (strand count, placement pattern, and layer structure) affects electrical resistance under tension, at knot positions, and across knot counts. Our results show that pattern choice can tune a cord's role as a high-sensitivity tension sensor, a stable conductive trace, or a knot-count detector using the same yarn. We further integrate thermochromic dyeing to enable reversible, heat-driven color change as a visual output channel, unobtrusive enough to blend naturally with traditional craft objects. We demonstrate the approach through three application prototypes rooted in Japanese traditional craft.

In recent years, Internet of Things(IoT) has become popular, the requirements for sharing the operation/mechanisms of IoT devices, such as Arduino and M5Stack are increasing. Moreover, owing to the coronavirus pandemic, many educational institutions have adopted online lectures, such as on-demand classes and online classes using video conference systems. For IoT programming education, these methods have challenges, such as a lack of linkage with real-world devices and source codes. In this study, we propose a system called “IoTeach”, which supports the learning of IoT programming by attaching a scripting language to sequential contents, such as videos and slides shared on the Web. The IoTeach can link videos and slides with real-world IoT devices and source codes. We describe the concept and implementation of the system in this study.