Polydimethylsiloxane/carboxylated hydroxylated multiwalled carbon nanotubes/polyimide composite membrane wearable flexible piezoresistive tactile sensor device with microsphere array

Abstract

This research proposed a flexible piezoresistive tactile sensor (FPTS) device with imprinted microsphere array to realize the accurate and stable acquisition of human motion data. The thickness of conductive membrane on the sensitivity of the sensor were investigated by FEM simulation, the copper microsphere array mold was prepared by multipoint imprinting process and the electromechanical response curves of piezoresistive tactile sensor consisting of Hydroxylated Multiwalled Carbon Nanotubes/Polyimide (carboxylated MWCNT/PI) composite membrane and Polydimethylsiloxane/Hydroxylated Multiwalled Carbon Nanotubes/Polyimide (PDMS/carboxylated MWCNT/PI) composite membrane with double‐sided microsphere were tested. The result shows that reduce the chord height can improve the sensitivity of the sensor. The composite structure with PDMS/carboxylated MWCNT/PI composite membrane reduces the overall stiffness of the microsphere structure, which is conducive to improve the sensitivity and minimum the detection limit of the FPTS. Multipoint imprinting technology is an efficient processing method to obtain high consistency microsphere array. The electromechanical response curves of piezoresistive tactile sensor consisting of PDMS/carboxylated MWCNT/PI composite membrane with double‐sided microsphere shows that the detection limits can reach 0.0289 kPa, and the sensitivity is 1.139 kPa−1. The sensor has high stability, especially when the wearing radius of curvature is more than 30 mm.

Research on multiwalled carbon nanotubes spray method for preparing flexible piezoresistive tactile sensor

“…Based on the microscale structure simulation of nacre, FPTS was prepared by Shi et al, 12 the FPTS achieved reliability and long‐term durability, confirming the enhancement of FPTS performance through microstructure design. Sun et al 13 investigated the influence of microsphere arrangement, diameter, and chord height ratio on the sensitivity of the sensor through finite element simulation, providing insights for the design of microstructures. In order to improve the durability of FPTS, many novel preparation methods have been proposed.…”

Strain and Pressure Sensors Based on MWCNT/PDMS for Human Motion/Perception Detection

“…Researchers have found that the pressure response characteristics of the resistive sensor can be enhanced by introducing the surface microstructure and the internal porous structure [ 19 ]. Appropriate surface structure treatment on the flexible substrate can effectively improve the sensing performance of resistive pressure sensors, including micro-pillar [ 20 ], pyramid structure [ 21 ], microsphere structure [ 22 ], plant-like surface microstructure [ 23 ], and interlocking nanopillar array structure imitating human hair [ 24 ]. Ma et al [ 25 ] fabricated a piezoresistive sensor based on ultra-light and super-elastic MX/rGO aerogel using the hybrid, three-dimensional structure of MXene and reduced graphene oxide and their pressure-sensitive characteristics, which can easily capture external stimulus signals below 10 Pa. Xu et al [ 26 ] proposed an all-solution-processed multi-mode biomimetic stretchable e-skin with a layered face-to-face asymmetric microstructure consisting of a PEDOT: PSS protective layer, an AgNWS conductive layer, and a silicone rubber matrix, which can achieve a variety of stimulus sensing including pressure and strain.…”

Flexible strain sensors with high sensitivity and large working range prepared from biaxially stretched carbon nanotubes/polyolefin elastomer nanocomposites

“…Flexible strain sensors have widely been employed in the wearable electronic products, human‐computer interaction, and health care, among others 1–5 . However, traditional strain sensors suffer from limited detectable strain range due to the rigid matrix.…”

“…and health care, among others. [1][2][3][4][5] However, traditional strain sensors suffer from limited detectable strain range due to the rigid matrix. Thus, conductive nanofillers are combined with a flexible matrix to enhance the flexibility and electrical properties to obtain high-performance strain sensors.…”