Preparation and performance of capacitive sensors with biomimetic skin wrinkle structure

With the rapid development of intelligent wearable technology, flexible capacitive sensors have shown broad application prospects in fields such as health monitoring, human-computer interaction, and electronic skin due to their simple preparation process and excellent electrical property. In order to improve the detection range and durability of the capacitive sensors, a capacitive sensor based on polydimethylsiloxane (PDMS) composite dielectric layer and expandable microsphere imitating the skin wrinkle structure is proposed. The structural morphology of the dielectric layer was evaluated by SEM and the electrical properties and human suitability of the sensor were investigated. The results show that the capacitive sensor has a wide detection range (0-242 kPa), high sensitivity (0.0079 kPa⁻¹), fast response time (230 ms), and excellent stable durability (9500 cycles). It also has good non-contact sensing performance with a non-contact sensitivity of 0.59%/cm. In practical applications, this sensor can accurately monitor bending movements of joints such as fingers, wrists and knees, as well as subtle physiological signals such as blinking and opening the mouth. The capacitive sensor has potential applications in the field of motion monitoring and health monitoring.