A Study of Highly Sensitive Wearable Strain Sensor Based on Graphical Sensitive Units

The sensitivity improvement is the choke point of the soft strain sensor’s development. This paper focuses on heightening the soft strain sensor’s sensitivity through changing the sensitive unit’s shape. The sensitive units in shape of square or sine wave with different periods were studied in this work. Silver nanowires (Ag NWs) in excellent electrical conductivity and flexible polydimethylsiloxane (PDMS) were used as sensitive nanomaterials and soft substrate. The soft strain sensor whose sensitive unit is double cycled square wave performs the highest sensitivity whose gauge factor (GF) reaches to 14763.8. Based on the high sensitivity, the sensor was applied on real-time detection of the human expression.