Textile-Based Washable Multimode Capacitive Sensors for Wearable Applications

Abstract

Nowadays, textile-based sensors are of great interest because of the significance of intelligent and smart textiles in wearable applications because of textiles’ washability, flexibility, and durability. We developed conductive yarn-based textile sensors for wearable multimode human-machine interfaces (HMIs), breathing, and walking pattern detection. The low-cost sewing process is used to develop interdigitated capacitive (IDC) sensor patterns on shirts, masks, and shoe soles using ultrafine highly conductive thread. Four sensor-based touchpads (SBTPs) were developed on the shirt and showed multiple modes of operation based on the pressure of the finger touch. The multimode capacitive sensors-based HMI is connected to the laptop wirelessly to perform three different functions from each sensor. The sensors exhibit a sensitivity of 34.675, 29.440, and 25.789 pF/N at low, medium, and high touch pressure. The developed mask detects the breathing pattern of humans, whether it’s slow, normal, or fast. Shoe Insole developed sensors to see the walking pattern, either slow, normal, or running. The response and recovery time of the sensor system is 11 and 10 ms, respectively. Sensors tested for 20000 detection cycles and responded stability. Also, the sensors responded accurately after washing with water and detergent water. Reported textile sensors are washable, flexible, stretchable, comfortable, and reusable, showing the practicality of proposed sensors for personalized healthcare, smart textiles, and electronic textiles (e-textiles).