Porous elastomer has been used as the dielectric layer of capacitive pressure sensors to reduce the Young's modulus and improve the sensitivity. In this paper, influence of permittivity on the sensitivity of porous elastomer-based capacitive pressure sensors is investigated. By introducing metallic particles (silver nanoparticles) into porous elastomer (polydimethylsiloxane) to increase its permittivity, the sensitivity of the porous composite-based capacitive pressure sensor is improved by 101.5% in the low-to-medium pressure regime (0-100 kPa). The capacitive pressure sensor also shows high linearity, good durability, and high noise immunity. Due to its high sensitivity, an artificial hand based on the capacitive pressure sensor can detect tiny pressure changes induced by wrist pulse and derive pressure distribution on different phalanges.
- Capacitive pressure sensor; porous elastomer; Ag-PDMS composite; high sensitivity; percolation threshold
- DIELECTRIC-CONSTANT; CRITICAL-BEHAVIOR; STRAIN SENSORS; COMPOSITES; SKIN; CONDUCTIVITY; RUBBER; FILMS; PDMS