A self-powered hybridized sensor inspired by human skin for mimicking fast and slow adaptation

Four types of mechanoreceptors in human skin are capable of sensing different stimuli and transmitting fast adapting (FA) and slow adapting (SA) signals to the brain. To mimic these functions, novel devices have been developed by coupling multiple sensing principles. However, complicated fabrication, high minimum detection limit, and low sensitivity hinder their wide application. In this paper, we report a self-powered mechanical stimulus receptor based on a combination of an artificial ion channel system, a single-electrode triboelectric nanogenerator, and a parallel plate capacitor, which can mimic human skin to monitor both dynamic and static stimuli. The introduction of the capacitive sensing part of this sensor overcomes the problem of conventional potentiometric sensors that are unable to monitor static stimuli due to insufficient electrolyte deformation at low pressure. This device detects external mechanical stimuli with high sensitivity (2.75 kPa−1 under dynamics and 1.18 kPa−1 under statics) and low detection limits (19.5 Pa). For the feasibility study, the signal simulation of Morse code is successfully implemented. In addition, the sensor has been shown to be able to detect human joint activity. This new sensor provides more options for future wearable electronic devices and human–computer interfaces.