Capacitive pressure sensors based on bioinspired structured electrode for human-machine interaction applications.

Flexible pressure sensor is a crucial component of tactile sensors and plays an integral role in numerous significant fields. Despite the considerable effort put forth, how to further improve sensitivity with ingenious yet easy-to-manufacture structures and apply them to emerging fields such as structure/materials recognition, human motion monitoring, and human-machine interaction remains a challenge. Here, we develop a highly sensitive flexible capacitive pressure sensor featuring a structured electrode layer with embedded microcracks and a dielectric layer with micro-convex structures, which are combined with an iontronic interface. The sophisticated design endows the sensor with superior perceptual performance, showing a relatively linear sensitivity of 1613 kPa in the range of 50 kPa and a detection limit of ∼6.7 Pa. Due to its excellent sensing capabilities, the sensors have been demonstrated for microstructure/material stiffness recognition and human motion monitoring. Furthermore, by integrating a single sensor with an inertial unit, the sensor gains the capability to output multiple sets of instructions. This work provides innovative design inspiration for flexible electronics.