Miura-Ori Microstructure-Enhanced Flexible Piezoresistive Pressure Sensor for Human Physiological Signal Monitoring

The flexible pressure sensor is a major type of device used for human health monitoring. Here, we present a novel design using Miura-ori microstructure to enhance the sensitivity of flexible pressure sensors. A spray–spin coating process suitable for mass production was used to form a carbon-nanotubes-doped flexible active layer on the surface of the microstructures. Compared with commonly used pyramid, cone, and hemisphere microstructures, the Miura-ori microstructure can improve 38.2%, 147.4%, and 235.7% of sensitivity in the sensing range 100–700 kPa, respectively. The presented sensor also showed good durability (1000 cycles under 300-kPa pressure), rapid response time (75 ms), and recovery time (75 ms). Moreover, the sensor was used to monitor the human wrist pulse signal and swallowing signals to show the capability of physiological signal monitoring. With excellent performance, the presented sensor has broad application potential in intelligent human health and motion monitoring.