A High-Performance Pressure Sensor Based on Discrete Structure and Multiple-Contact Mechanism for Detecting Human Motions and Image Description

A flexible pressure sensor is proposed based on discrete structure and multiple-contact mechanism (DSMM). It has capability to optimize performances of those resistive-type pressure sensors, which have disadvantage of small measuring range to trade for super high sensitivity. The proposed DSMM pressure sensor has tri-layer structure consisting of top electrode, graphite nanosheets/polyimide (GNS/PI) resistor matrix, and bottom electrode. As the contact area between sensing elements enlarges, more and more pixels of resistor matrix contact with top electrode to realize parallel connection for expanding measuring range up to 410 kPa. The pressure sensor still exhibits the high sensitivity (0.38 /kPa for low pressure, 0.79 /kPa for high pressure) and ultralow detection limit (15 mg), and there is no response delay or hysteresis in contact process. Human motions and tactile image are measured, which demonstrates that the pressure sensors have applicability for biological signals monitoring and have potential applications combining machine vision and tactile.