A highly stable and sensitive sensor with linear response enabled by embedded droplet printing and bio-inspired design

•The sensor simultaneously had high sensitivity and linearity in a small strain.•The embedded structure enhances durability and reduces the response time of sensor.•An effective circuit model is adopted to elucidate the linear change of resistance.•The propagation mechanism of mesh crack in RGO patterns is explored. Skin-attachable sensors detect sound through skin contractions. However, the performances of sensors are constrained due to the poor linearity and structural instability. In this work, programmable RGO (reduced graphene oxide) patterns were deposited on viscous PDMS via embedded droplet printing (EDP) technology. The sensor exhibited excellent overall performances, including high sensitivity (GF = 2200) coupled with excellent linearity (0.9979), fast response time (200 µs), and outstanding durability (10,000 cycles) in small strain regions. Actually, benefiting from the embedded structure, narrow but thick graphene patterns were deposited, which improved the sensitivity of the sensor. Further, the embedded structure enabled the strong adhesion between RGO patterns and PDMS substrate, thereby enhancing sensor durability while significantly reducing the response time. Additionally, the mesh crack propagation mechanism of the RGO patterns during deformation was explored, and an effective electrical circuit model was adopted to elucidate the linear change of resistance. This work offered an effective approach to fabricate skin-attachable sensors, showing the potential ability in wearable health monitoring systems, such as speech pattern recognition.