All textile-based robust pressure sensors for smart garments

Abstract

Textile-based pressure sensors with good comfortness and breathability can be easily integrated into garments for smart wearables. Nevertheless, scalable construction of all textile-based pressure sensors with good mechanical robustness and desirable sensor performance still remains a great challenge. Here, a facile, low-cost, and scalable approach is proposed to fabricate a new paradigm of all textile-based and mechanically robust pressure sensors. These pressure sensors consist of a top elastic piezoresistive sensing fabric and a bottom textile-based robust interdigital electrodes. The top piezoresistive sensing fabric is fabricated by controllably depositing robust polyurethane/carbon nanotubes composites on a highly elastic Venetian fabric through electrostatic layer-by-layer assembly. The bottom interdigital electrodes are prepared by screen printing of an elastic and robust carbon ink on a polyester fabric. Notably, the conductive networks in both of the piezoresistive sensing layer and the bottom electrodes are firmly embedded in elastomer substrates rather than directly attached onto the fabric surface, endowing the pressure sensors with superior mechanical robustness. The as-fabricated all textile-based pressure sensors exhibit high sensitivity (3.42 kPa−1), fast response/recovery time (32 ms/4 ms), good cycling stability (10 000 cycles), superior robustness against mechanical bending (10 000 cycles) and chemical washing. As demonstrations, the pressure sensors are integrated into diverse garments for wireless and real-time monitoring of various human physiological activities, including joint bending, muscle activity, object grasping, etc. This proposed simple but efficient approach for fabricating all textile-based pressure sensors with superior robustness opens up new opportunities for the further development of smart garments and wearable devices.