Capacitive Stretchable Strain Sensors Based on Wavy-Structured Metal Electrodes

Abstract

Stretchable strain sensors are of great importance in developing intelligent robotics, virtual reality, and e-skins. Here, we propose a capacitive stretchable strain sensor based on wavy structured interdigital metal electrodes encapsulated in elastomers, where wavy design not only endows metal electrodes with stretchability, ensuring long-term stability, but also provides sidewalls to form 3D nonplanar capacitor. Distances between electrodes change with the elongation when stretching, resulting in capacitance variation with high sensitivity. The devices are fabricated, and the sensing properties are characterized. The simulation on device deformation, stress distribution, and sensitivity is also performed for validation and comparison. The presented stretchable strain sensor is reliable, suitable with high-volume manufacturing, and promising in various applications. © 2021 IEEE.