Gu Jimin, Kwon Donguk, Ahn Junseong, Park Inkyu
Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, South Korea.
Package Process Development Team Samsung Electronics, 158 Baebang-ro, Baebang-eup, Asan-si, Chungcheongnam-do, South Korea.
ACS Appl Mater Interfaces. 2020 Mar 4;12(9):10908-10917. doi: 10.1021/acsami.9b18069. Epub 2020 Jan 29.
A number of flexible and stretchable strain sensors based on piezoresistive and capacitive principles have been recently developed. However, piezoresistive sensors suffer from poor long-term stability and considerable hysteresis of signals. On the other hand, capacitive sensors exhibit limited sensitivity and strong electromagnetic interference from the neighboring environment. In order to resolve these problems, a novel stretchable strain sensor based on the modulation of optical transmittance of carbon nanotube (CNT)-embedded Ecoflex is introduced in this paper. Within the film of multiwalled CNTs embedded in the Ecoflex substrate, the microcracks are propagated under tensile strain, changing the optical transmittance of the film. The proposed sensor exhibits good stretchability (ε ≈ 400%), high linearity ( > 0.98) in the strain range of ε = 0-100%, excellent stability, high sensitivity (gauge factor ≈ 30), and small hysteresis (∼1.8%). The sensor was utilized to detect the bending of the finger and wrist for the control of a robot arm. Furthermore, the applications of this sensor to the real-time posture monitoring of the neck and to the detection of subtle human motions were demonstrated.
最近已经开发出了一些基于压阻和电容原理的柔性可拉伸应变传感器。然而，压阻式传感器存在长期稳定性差和信号显著滞后的问题。另一方面，电容式传感器灵敏度有限，且受到来自相邻环境的强烈电磁干扰。为了解决这些问题，本文介绍了一种基于嵌入碳纳米管（CNT）的Ecoflex光透射率调制的新型可拉伸应变传感器。在嵌入Ecoflex基板的多壁碳纳米管薄膜中，微裂纹在拉伸应变下扩展，从而改变薄膜的光透射率。所提出的传感器具有良好的拉伸性（ε≈400%），在ε = 0 - 100%应变范围内具有高线性度（> 0.98）、优异的稳定性、高灵敏度（应变片系数≈30）和小滞后（~1.8%）。该传感器用于检测手指和手腕的弯曲，以控制机器人手臂。此外，还展示了该传感器在颈部实时姿势监测和细微人体运动检测方面的应用。
