High‐Linearity, Response‐Range Adjustable Force Sensors Based on a Yarn/Film/Spacer Triboelectric Device Design

Abstract

In this study, a novel triboelectric device is developed that consists of a silicone‐coated conductive yarn and a PET film as active substances, and an elastic spacer as a force controller. The silicone‐coated yarn is prepared by applying a thermally curable silicone to conductive yarns using a simple but continuous method. The device made of 20 cm long yarn can generate peak voltage as high as 225 V and current outputs of 2.4 µA. The elastic spacer functions to maintain the yarn and PET film in a separate state when no force is loaded and to adjust the response threshold and detection range by changing the spacer area. In comparison to the triboelectric force‐sensors reported previously, this yarn/film device shows a much larger detection range (24–380 N) and higher flexibility in tuning the detection range. The output voltage‐input force curves of the devices have an R2 value above 0.91, indicating the good linearity between the input force and voltage output. Moreover, a theoretical model is developed to elucidate the influence of the spacer area on the detection range and sensitivity. Such a yarn/film/spacer sensor design may be useful for the development of low‐cost force sensors for various applications.

Recent progress in the fabrication and processing of triboelectric yarns

“…(c) A homemade-coating device for continuous production. [97] Reproduced with permission: Copyright 2021, John Wiley and Sons. (d) The surface and cross-sectional image of the coated yarn.…”

“…(d) The surface and cross-sectional image of the coated yarn. [97] Reproduced with permission: Copyright 2021, John Wiley and Sons.…”

Self-Powered Sensing for Non-Full Pipe Fluidic Flow Based on Triboelectric Nanogenerators

“…Wang’s group first proposed triboelectric nanogenerators (TENGs) based on the coupling of the triboelectrification effect and electrostatic induction in 2012. − The TENGs can effectively obtain energy from nature, such as ocean, vibration, and wind. , They can not only collect energy more efficiently in a low-frequency environment − but also have the advantages of no external energy supply and low cost . In addition, TENGs can also be used as a self-powered sensor. − They have been widely applied, such as driving state sensing, − liquid level sensing, − flow sensing, − chemical sensing, , flow rate sensing, − pressure sensing, − and so on. − Among them, flow sensors have been widely developed. For example, Wang’s group designed a water-fluid-driven rotating TENG (WR-TENG) for pipeline flow monitoring.…”

Challenges in Materials and Devices of Electronic Skin

“…This approach is especially effective for capacitive sensors by allowing dielectric structure optimizations, such as thickness or modulus (Figure b), and filler concentration . Besides, changing the spacing area could endow triboelectric sensors with tunable linear sensing range . The second cause of poor linearity is that the output signal quickly approaches saturation when the input stimulus is relatively small.…”

“…132 Besides, changing the spacing area could endow triboelectric sensors with tunable linear sensing range. 133 The second cause of poor linearity is that the output signal quickly approaches saturation when the input stimulus is relatively small. Therefore, the linear working range is shortened, since saturated response inevitably degrades sensitivity.…”