Fabrication of high sensitivity and stable strain sensors based on composite folded structures via embedded 3D printing

Flexible strain sensors provide a practical and straightforward detection technique for the human motion to convert strain changes into resistance changes. We present extremely sensitive and stable strain sensors prepared by embedded 3D printing technology in this paper. By incorporating polydimethylsiloxane (PDMS) material and printing a folded structure, the sensing performance of the sensors is explored. The combination of PDMS with high Poisson’s ratio and silicone rubber with low modulus of elasticity endow strain sensors with an ideal combination of great sensitivity and strong stretchability (gauge factor of 6 in the strain of 50%, good durability (stretch/release test of 1000 cycles). The strain sensor attached to the hand demonstrates good sensing performance.