All Paper‐Based, Multilayered, Inkjet‐Printed Tactile Sensor in Wide Pressure Detection Range with High Sensitivity
Tae Hoon Lee, Yunsung Kang, Kwanhun Kim, Sangjun Sim, Kyubin Bae, Yeunjun Kwak, Wonkeun Park, Minhyeong Kim, Jongbaeg Kim
Abstract
Abstract Paper has attracted considerable interest as a promising pressure‐sensing element owing to its foldability/bendability and deformability due to its high porosity. However, paper‐based tactile sensors reported hitherto cannot achieve high sensitivity and a wide sensing range simultaneously. In this study, a resistive tactile sensor using carbon nanotube‐ and silver nanoparticle‐printed mulberry paper as a pressure‐sensing element and electrodes, respectively, is developed. The rough surface and high inner porosity of mulberry paper induce a significant change in the contact area when a multilayer‐stacked structure is used, resulting in increased sensitivity to pressure. Moreover, the enhanced mechanical robustness of mulberry paper originating from the highly bonded network of long and thick fibers affords a wide pressure‐sensing range. The sensor exhibits a high sensitivity exceeding 1 kPa −1 in an applied pressure range of 0.05–900 kPa; this achievement has not been reported among paper‐based tactile sensors. Furthermore, the sensor exhibits a fast response/relaxation time, low detection limit, high resolution, high durability, and high flexibility. The advantages of the sensor afford several applications, including a crosstalk‐free pressure sensor array, a three‐axis pressure sensor, and wearable devices for measuring signals from a user.