Flexible Strain Sensors Based on Liquid Metal With Optimized Atomizing Spraying for Wearable Applications

Flexible strain sensor based on liquid metal (FSS-LM) have great application potential in wearable devices, biomedicine, and soft robots due to their huge deformability, low hysteresis, and high durability. However, the existing fabrication method for the sensor faced with some challenges, such as high cost, cumbersome process, and long preparation time, which affect the development of the flexible sensors. Herein, this article reported a FSS-LM through atomizing spraying process. We optimized the spraying process, remarkably improving spraying quality. On the basis of the optimized spraying process, we quickly fabricated the FSS-LM with low cost. The sensor shows low hysteresis (1.18%), fast response (212 ms), long durability (2000 stretching and releasing cycles), excellent dynamic and static performance, as well as good repeatability. Finally, the developed sensor was used to detect a variety of activities, including the bending of human joints and robot fingers, expansion of the balloon, and the growth of plant stems. The results show that the FSS-LM exhibits great potential in the field of wearable devices.