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Soft compression sensors represent a promising approach to provide proprioceptive feedback for robotic manipulators. However, dielectric elastomer sensors work well as stretch sensors, their sensitivity is low when used as com- pression sensors, due to the incompressibility of elastomers. Therefore, the simple electrode/membrane/electrode sensor configuration is not sensitive enough to a low range of force. Here, we report on the use of a patterned silicone layer (it is considered as pillars) to produce a compressible dielectric elastomer sensor to detect deformation and pressure. Interdigitated electrodes (IDEs) are patterned on the backside of the sensor to generate a fringing electric field into the dielectric material. The deformation of the silicone pillars causes changes in the relative permittivity due to changes in the air-volume fraction of each component. By using IDEs on the backside of the sensor, there is no need for compliant electrodes, and a simple printed circuit board (PCB) can be used. This simplifies the fabrication process and takes advantage of the good conductivity and reliability of the PCB copper electrodes. We optimized different parameters of the sensor such as the pillar’s dimension which affects the stiffness and electrical sensitivity of the sensor. Using our optimization process, we demonstrate sensors that exhibit a capacitance change of more than 36% for an input force of 60N. Our sensor combines high sensitivity with a simple fabrication and assembly, thus making it ideal for applications like the manipulation of fragile objects.
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