Design and performance of stretchable resistive sensor based on knitted loop structures for motion detection

The urgent need for flexible strain sensors that are both aesthetic and functional is addressed, given the rapid development of smart wearable technology and the improvement of material level. To achieve this, silver-plated yarns based on nylon and nylon wrapped spandex were directly knitted into the sensor using cross-knit intarsia and plating technology. Five samples, with varying percentages of loops and tuck loops, were designed. The results indicated that the sensor demonstrated a GF of 2.80 kPa −1 at the Lx-axis and 3.67 kPa −1 at the Ly-axis, showing good repeatability during 1000 cycles of stretch/release. Moreover, it exhibited fast responsiveness, enabling it to discriminate between different rates of stretch. The sensor's potential for application in wearable smart medical monitoring was demonstrated by its ability to be embedded in garments for joint motion monitoring. These findings collectively suggest that the designed knitted strain sensor holds promising potential for use in the field of wearable smart medical monitoring.