A Hypersensitive, Fast-response Biomimetic Pressure Sensor Inspired by the Superior Sensing Structures of the Dragonfly’s Neck

Abstract

Flexible piezoresistive pressure sensors have attracted much attention for applications in health monitoring and human-machine interfaces due to their simple device structures and easy-to-read signals. For practical applications, the deployment of flexible pressure sensors characterized by high sensitivity and fast response time is imperative for the rapid and accurate detection and monitoring of tiny signals. Such capabilities are essential for facilitating immediate feedback and informed decision-making across a spectrum of contexts. Drawing lessons from the hypersensitive and fast-responding pressure sensing structures in the dragonfly’s neck (for stable imaging during its highly maneuverable flight), a Biomimetic Piezoresistive Pressure Sensor (BPPS) with exquisite mechanically interlocking sensing microstructures is developed. Each interlocking perceptual structure pair consists of an ox-horn-shaped and a mushroom-shaped structural unit. Through the characteristic configuration of the perceptual structure pair, the BPPS realizes a fast gradient accumulation of the contact area, thus synergistically enhancing the sensitivity and fast response capability. Remarkably, the sensitivity of the BPPS reaches 0.35 kPa^− 1, which increased by 75% compared to the 0.2 kPa^− 1 of the pressure sensors without biomimetic structures. Moreover, the BPPS also achieves rapid response/recovery times (< 90/15 ms). Our BPPS finds utility in tasks such as identifying objects of different weights, monitoring human respiratory status, and tracking motion, demonstrating its potential in wearable healthcare devices, assistive technology, and intelligent soft robotics. Moreover, it possesses the advantages of high sensitivity and fast response time in practical applications.