Passive and Space-Discriminative Ionic Sensors Based on Durable Nanocomposite Electrodes toward Sign Language Recognition

This work developed an ionic sensor for human motion monitoring by employing durable H-reduced graphene oxide (RGO)/carbon nanotubes (CNTs)/Ag electrodes and an ionic polymer interlayer. The sensor functions as a result of unbalanced ion transport and accumulation between two electrodes stimulated by applied deformation. The networking structure and stable electrodes provide convenient ion-transport channels and a large ion accumulation space, resulting in a sensitivity of 2.6 mV in the strain range below 1% and high stability over 6000 bending cycles. Ionic sensors are of intense interest motivated by detecting human activities, which usually associate with a large strain or deformation change. More importantly, direction identification and spatial deformation recognition are feasible in this research, which is beneficial for the detection of complex multidimensional activities. Here, an integrated smart glove with several sensors mounted on the hand joints displays a distinguished ability in the complex geometry of hand configurations. Based on its superior performance, the potential applications of this passive ionic sensor in sign language recognition and human-computer interaction are demonstrated.