Development of a Korean Sign Language Translation System Using Knitted Strain Sensor-Integrated Smart Gloves

Herein, an integrated system is developed based on knitted strain sensors for real-time translation of sign language into text and audio voices. To investigate how the structural characteristics of the knit affect the electrical performance, the position of the conductive yarn and the presence or absence of elastic yarn are set as experimental variables, and five distinct sensors are manufactured. A comprehensive analysis of the electrical and mechanical performance, including sensitivity, responsiveness, reliability, and reproducibility, reveals that the sensor with a plain plated knit structure, no elastic yarn included, and the conductive yarn positioned uniformly on the back exhibits the best performance, with a gauge factor (GF) of 88. The sensor demonstrates high sensitivity and a fast response speed to finger joint bending. Additionally, it exhibits stable reproducibility and reliability across various angles and speeds, thereby confirming its optimized characteristics for sign language recognition. Based on this design, an integrated textile-based system is developed by incorporating the sensor, interconnections, snap connectors, and a microcontroller unit (MCU) with built-in Bluetooth Low Energy (BLE) technology into the knitted glove. The completed system successfully recognizes 12 Korean Sign Language (KSL) gestures in real time and outputs them as text and audio voices in conjunction with a dedicated application. Thus, the present study quantitatively elucidates the structure-performance relationship of a knitted sensor and proposes a wearable system that accounts for real-world usage environments, thereby demonstrating the commercialization potential of the technology.