A novel double-sided fabric strain sensor array fabricated with a facile and cost-effective process

Electronic textiles face challenge in fabricating stretchable, double-sided circuits with reliable interfaces. In this study, a double-sided strain sensor array was designed and prepared on an elastic fabric substrate by printing the sensing areas and interconnects using a single identical conductive composite paste. By controlling the viscosity of the printing paste, the conductive tracks on both sides of the porous fabric were insulated, except for the via holes at the specified positions. Through fabrication using a facile and cost-effective method, the fabric strain sensor array exhibited preferable consistency, a reliable connection interface, sufficient environmental stability, and long fatigue life (similar to 10,000 cyclic loadings). An optimized scanning readout approach was applied to read the signals of the sensor array with an error of less than 1%. Additionally, the spatial strain distribution of the knee movement captured by the sensor array demonstrated its advantages in capturing human dynamic motions. This method paves the way for the design and fabrication of stretchable-fabric-based sensor arrays and circuits that can be applied to intelligent wearable systems.