Flexible Hydrogel Capacitive Pressure Sensor for Underwater Applications

This paper reports development of a novel, flexible hydrogel based capacitive pressure sensor. It features a simple design of hydrogel thin film sandwiched between two gold electrodes. The sensor shows linear increase in output with increase in pressure. The microporous network of hydrogel enables high water retention while its flexible and stretchable structure ensures usage over large areas. These factors, combined with its stability in water, make it an ideal candidate for underwater applications. Further, the physical and chemical properties of hydrogels can be tailored to tune the capacitance to specific sensing needs. Flexible arrays of capacitive sensors with hydrogel hold great potential for underwater smart skin applications.