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

AbstractIn 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.