Simple fabrication of high-sensitivity capacitive tactile sensor based on a polydimethylsiloxane dielectric layer using a biomimetic gray kangaroo leg structure

Design of the capacitive tactile sensor with ultra-high sensitivity and fast response/recovery times is critical to the advancement of wearable devices. However, achieving both fast response/recovery time and ultra-high sensitivity simultaneously is a huge challenge. In this work a simple and easy-to-prepare flexible capacitive tactile sensor is presented, using a biomimetic gray kangaroo structured dielectric layer of polydimethylsiloxane. By using finite element analysis to study the influences of various structures, the test result of the experimentally optimized tactile sensor showed ultra-high sensitivity (1.202 kPa-1), outstanding response and recovery time (60/85 ms), wide pressure range (0-220 kPa), and excellent stability. Finally, the tactile sensors are tested for practical applications, including robot tactile, human motion monitoring, and Morse code detection.