Ultra-flexible graphene/nylon/PDMS coaxial fiber-shaped multifunctional sensor
Peddathimula Puneetha, Siva Pratap Reddy Mallem, Sung Cheol Park, Seoha Kim, Dong Hun Heo, Cheol Min Kim, Jaesool Shim, Sung Jin An, Dong‐Yeon Lee, Kwi‐Il Park
Abstract
The development of flexible and wearable devices is mainly required for tactile sensing; as such devices can adapt to complicated nonuniform surfaces, they can be applied to the human body. Nevertheless, it remains necessary to simultaneously achieve small-scale, portable, and stable developments in such devices. Thus, this work aims at fabricating a novel, lightweight, ultra-flexible, and fiber-shaped coaxial structure with a diameter of 0.51 mm using polydimethylsiloxane/graphene/nylon material, based on piezoresistive and triboelectric principles. The piezoresistive-based robotic-hand-controlled sensor thus realized exhibits a response time of 120 ms and a fast recovery time of 55 ms. Further, the piezoresistive-based sensors effectively feature whisker/joystick-guided behaviors and also sense the human finger contact. Owing to the triboelectric-based self-powered nanogenerator behavior, the resulting sensor can convert mechanical motion into electrical energy, without adversely affecting human organs. Moreover, this triboelectric-based human finger sensor can be operated under different bending modes at specific angles. Notably, this multifunctional sensor is cost-effective and suitable for various applications, including robotic-hand-controlled operations in medical surgery, whisker/joystick motions in lightweight drone technology, and navigation with high-sensitivity components.