Ultra‐Robust and Sensitive Flexible Strain Sensor for Real‐Time and Wearable Sign Language Translation

Abstract Flexible strain sensors with high sensitivity and high mechanical robustness are highly desirable for their accurate and long‐term reliable service in wearable human‐machine interfaces. However, the current application of flexible strain sensors has to face a trade‐off between high sensitivity and high mechanical robustness. The most representative examples are micro/nano crack‐based sensors and serpentine meander‐based sensors. The former one typically shows high sensitivity but limited robustness, while the latter is on the contrary. Herein, ultra‐robust and sensitive flexible strain sensors are developed by crack‐like pathway customization and ingenious modulation of low/high‐resistance regions on a serpentine meander structure. The sensors show high cyclic stability (10 000 cycles), strong tolerance to harsh environments, high gauge factor (>1000) comparable with that of the crack‐based sensor, and fast response time (<58 ms). Finally, the sensors are integrated into a wearable sign language translation system, which is wireless, low‐cost, and lightweight. Recognition rates of over 98% are demonstrated for the translation of 21 sign languages with the assistance of machine learning. This system facilitates achieving barrier‐free communication between signers and nonsigners and offers broad application prospects in gesture interaction.