Highly Sensitive Piezoelectric E‐Skin Design Based on Electromechanical Coupling Concept

Abstract

AbstractStretchable electronic skin (e‐skin) paves the way for applications that exceed the scope of intrinsic rigid devices and hard‐to‐stretch sensors. The broad application range of flexible e‐skins benefits from device architectures that can simultaneously provide mechanical flexibility and superior sensitivity. Classic fractal design provides a simple architecture to achieve the desired flexibility through structural design for improved wear comfort, but at the expense of sensor sensitivity. In this study, the proposed method addresses the trade‐off between stretchability and sensitivity in fractal design. A high‐sensitivity e‐skin is obtained by eliminating the effect of negative charge on the output by applying the concept of electromechanical coupling. This concept for designing e‐skins with high sensitivity is validated through the delicate patterning of hard‐to‐stretch functional materials. Further, human speech signals are acquired through the integration of e‐skin with signal processing circuits, and speech pattern recognition is realized using machine learning. The stretchable e‐skin with an enhanced gauge factor illustrates the wider application of this concept for improving the sensitivity of stretchable electronic functional materials.