Flexible piezoresistive pressure sensor based on wrinkled layers with fast response for wearable applications

Abstract

Flexible piezoresistive sensors are promising candidates for vital components of prospective wearable sensing systems in human-centered intelligent applications. Herein, we present a novel flexible piezoresistive pressure sensor based on the structure of silver nanowires (AgNWs) on polydimethylsiloxane (PDMS) with a wrinkled surface. Modifying the PDMS microstructure enables the sensor to obtain different sensitivities and pressure ranges. At the optimal conditions, our sensor exhibits a high sensitivity of 2.588 kPa−1 and a large pressure range with a very low detectable pressure limit (<1 Pa), which can measure a seed weight of sesame (∼2 mg). Furthermore, The elastic microstructure-based piezoresistive sensor also possesses a very fast response time (10 ms), rapid recovery (20 ms), and excellent cycling stability. The real-time pressure detection ability is demonstrated by the touching behavior, the muscle and joint movement and the vocalization recognition, presenting great application potential in human–machine interaction, human motion monitoring and intelligent robotic systems.