Flexible Capacitive Hydrogel Tactile Sensor with Adjustable Measurement Range Using Liquid Crystal and Carbon Nanotubes Composites

In this paper, we present a $4\times4$ capacitive pressure tactile sensor fabricated with new materials, which consists of one dielectric layer and two electrode layers. The dielectric layer is composed of carbon nanotubes dispersed in liquid crystal, which is surrounded by a hydrogel elastomeric membrane. An upper Au parylene film and a lower Au parylene film taped on the kapton tapes are served as the electrode layers. The properties of the devices are well characterized and the capability of adjustable measurement range is successfully realized. Experimental results demonstrate that the capacitance will change with the different driving frequency and voltage accordingly.