Textile-Based, Interdigital, Capacitive, Soft-Strain Sensor for Wearable Applications

Materials (Basel). 2018 May 10;11(5):768. doi: 10.3390/ma11050768.

Abstract

The electronic textile area has gained considerable attention due to its implementation of wearable devices, and soft sensors are the main components of these systems. In this paper, a new sensor design is presented to create stretchable, capacitance-based strain sensors for human motion tracking. This involves the use of stretchable, conductive-knit fabric within the silicone elastomer matrix, as interdigitated electrodes. While conductive fabric creates a secure conductive network for electrodes, a silicone-based matrix provides encapsulation and dimensional-stability to the structure. During the benchtop characterization, sensors show linear output, i.e., R² = 0.997, with high response time, i.e., 50 ms, and high resolution, i.e., 1.36%. Finally, movement of the knee joint during the different scenarios was successfully recorded.

Keywords: capacitive sensors; conductive fabrics; electronic textiles; silicone elastomer; soft strain sensors; wearable electronics.