Tunable soft pressure sensors based on magnetic coupling mediated by hyperelastic materials

Abstract

Recent advances in pressure sensors have garnered significant interest due to their promising applications in healthcare, robotics and wearable technology. In these fields, there is an ever-increasing demand for soft sensors that can conform to complex surfaces, such as the human body. However, current sensors often face limitations in measurable pressure ranges and customization involves complex manufacturing processes. In this study, we introduce an innovative solution for producing soft pressure sensors with varying maximum detection pressures. By utilizing a magnetic transduction mechanism and different hyperelastic materials, we have developed sensors that can adapt to irregular surfaces. These sensors measure a wide range of pressures, from ultra-low to medium, and offer variable stiffness, sensitivity, and measurement ranges. The sensors we manufactured exhibit a detection range from 6.8 to 77.4 kPa, a sensitivity range between -5.1 × 10^-2 and -0.4 × 10^-2 kPa^-1, a short recovery time of 0.4 s, low hysteresis values during repeated loading/unloading cycles, and stable response over thousands of pressure cycle. Proof-of-concept experiments validated the sensors’ suitability for breathing monitoring and finger tap detection, highlighting their potential in medical and robotic applications. The results demonstrate a robust strategy for controlling the performance of soft pressure sensors, positioning them as promising candidates for diverse pressure sensing applications.

Keywords

Soft sensors / pressure sensing / wearable sensors / breathing monitoring

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