Facile Fabrication of Flexible Pressure Sensor with Programmable Lattice Structure
We introduce a structure designable lattice structure pressure sensor (LPS) produced by bottom-up digital light processing (DLP) 3D printing technique, which is capable of efficiently producing 55 high fidelity lattice structure models in 30 min. The LPS shows high sensitivity (1.02 kPa−1) with superior linearity over a wide pressure range (0.7 Pa to 160 kPa). By adjusting the design parameters such as lattice type and layer thickness, the electrical sensitivities and mechanical properties of LPS can be accurately controlled. In addition, the LPS endures up to 60000 compression cycles (at 10 kPa) without any obvious electrical signal degradation. This benefits from the firm carbon nanotubes (CNTs) coating derived from high-energy ultrasonic probe and the subsequent thermal curing process of UV-heat dual-curing photocurable resin. For practical applications, the LPS is used for real time pulse monitoring, voice recognition and Morse code communication.
Fabrication Process
The lattice-structure sensor was manufactured by 3D Printing.
Varied sizes of the sensor.
The printed sensor was then treated by an ultrasound probe carbon nanotubes (CNTs) coating.
After heat treatment, the sensor was coated with CNTs
Flexibility of the coated sensor.
Lattice structure pressure sensor (LPS).
Electrical and mechanical test
(a) Effects of lattice types on the pressure sensitivity of LPS. (b) Effects of rod diameter on the pressure sensitivity of LPS. (c) Effects of active layer thickness on the pressure sensitivity of LPS. Notably, when one variable among the lattice types, rod diameter, and active layer thickness is changed, the other two are fixed. (d) I−V curves of the LPS with various applied pressure. (e) Real time current and pressure response at a cyclic applied force of 5 N. (f) Response and release time of LPS under loadings of 1, 10, and 100 kPa. (g) Sensitivities curves at different compression speeds. (h) Long time cyclic test under a repetitive pressure loading of 10 kPa at a frequency of 0.5 Hz.
Applications
LPS can reproductively recognize voice signal
Monitoring of pulse wave under a preload with the elastic TPU tape.
Above photos by Yiming Yin & Ling Qin
Pubilcation
Yin, Y. M., Li, H. Y., Xu, J., Zhang, C., Liang, F., Li, X., Jiang. Y., Cao, J.W., Feng, H.F., Mao, J.N., Qin, L., Kang, Y.F., Zhu, G. 2021. Facile Fabrication of Flexible Pressure Sensor with Programmable Lattice Structure. ACS Applied Materials & Interfaces. 2021 13 (8), 10388-10396. DOI: 10.1021/acsami.0c21407.
by Yiming Yin, Huayang Li, Jin Xu, Chen Zhang, Fei Liang, Xin Li, Yang Jiang, Jinwei Cao, Hanfang Feng, Jianan Mao, Ling Qin, Yifan Kang, and Guang Zhu
June 2019 - Sept. 2019