Effect of bonding and washing on electronic textile stretch sensor properties

Knit e-textile sensors can be used to detect stretch or strain, and when integrated directly into wearable garments, they can be used to detect movement of the human body. However, before they can reliably be used in real-world applications, the garment construction technique and the effects of wear due to washing need to be considered. This paper presents a study examining how thermal bonding and washing affects piezo-resistive textile sensors. Three textile strain sensors are considered all using Technik-tex P130B as the conductive material: i) conductive fabric only, ii) conductive fabric bonded to on one side to Eurojersey fabric, and iii) conductive fabric with Eurojersey bonded on top and bottom of the conductive fabric. The sensors' performance is evaluated using a tensile tester while monitoring their electrical resistance before and after washing. The findings show that a single layer of bonding is the ideal construction and that after three wash cycles the sensor remains reliable.