Design of Capacitive Pressure Sensors Integrated With Anisotropic Wedge Microstructure-Based Dielectric Layer

The microstructure design of the dielectric layer has been demonstrated to enhance the measurement performance of flexible pressure sensors. Nevertheless, current isotropic and anisotropic microstructures are incapable of overcoming the substantial rise in compressive stiffness accompanying increased pressure, leading to compromised performance and restricted linear measurement ranges. For the above problem, a design of the capacitive pressure sensor integrated with the anisotropic wedge microstructure (AWM)-based dielectric layer is proposed. First, utilizing the capacity of AWM to induce bending deformations, the capacitive pressure sensor integrated with the AWM-based dielectric layer is designed. Then, a novel electromechanical model considering AWMs’ intrinsic relationship is proposed for the sensors and shows its capability for linear measurement. Furthermore, according to the model analysis, the capacitive pressure sensors integrated with AWMs-based dielectric layers are fabricated cost-effectively, and the accuracy of the linear electromechanical model is also experimentally verified. Finally, the experimental results demonstrate that the pressure sensor based on AWMs has a wide highly sensitive linear measurement range (0–20 kPa;
$R^{{2}}$
= 99.96%), fast recovery time (33.8 ms), and excellent cycle stability (5000 cycles), which can make it promising for a wide range of applications in fields, such as wearable devices and flexible operation of robots.