The Tunable Deformation of Microfluidic Strain Sensor Based on Auxetic Metamaterial

Microfluidic system has played a key role in realizing wearable biosensing and biochemical analysis. With the intrinsic flexibility and stretchability, the microfluidics is also a promising candidate for assembling the flexible sensors for the force signals. As the force detection with microfluidics highly relies on the structural deformation of the microfluidic channel, the mechanical property of the microfluidic device is closely related to its performance in a wide range. In this study, the feasibility to regulate performance of the microfluidic strain sensor by modulating its mechanical properties with the auxetic metamaterial is discussed with the finite element analysis. By analyzing the strain distributions in the sensors with/without the embedded auxetic frame, the abilities of the auxetic frame to override the device's intrinsic mechanical property and regulate the device's performance are presented. The influences of thickness, modulus, and location of the auxetic frame on the regulation effect are also discussed with the simulation results.