Recent Advances in Bioabsorbable Wireless Passive Pressure Sensors

In this paper, we introduce a wireless passive flexible pressure sensor based on the RFID backscattering coupling principle, which uses ferrite film as reflection layer, flexible sponge as intermediate layer and RFID tag as data transmission layer. The sensor gain and Young’s modulus were simulated by finite element methods, and the sensor sensitivity was measured using a pressure test system. Finally, the same conclusion is obtained: in the same thickness, the middle layer of low-density sponge sensor has higher sensitivity. In addition, a series of performance tests were conducted, and the maximum working distance of the sensor was $10 \mathrm{~cm}, 0.91 \%$ in the temperature measurement range $\left(25{ }^{\circ} \mathrm{C} \sim 45^{\circ} \mathrm{C}\right)$ and 0.89% in the humidity measurement range (43% RH $\sim 8.2 \mathrm{RH}$). The wireless passive flexible pressure sensor has simple structure and low production cost, which increases the measurement distance of the wireless passive sensor in the near field range, and has a good application prospect in the intelligent medical field such as medical bandage pressure detection and plantar pressure detection.