Measurement of silicone rubber hardness by use of a quartz-crystal tuning-fork tactile sensor

Silicone rubber hardness has been investigated experimentally using a quartz-crystal tuning-fork tactile sensor. Silicone rubber hardens as the value of the rubber hardness tester increases. Eight silicone rubbers (the values of rubber hardness tester are JIS885, 70, 65, 60, 50, 45, 40, and 35) are investigated by a quartz-crystal tuning-fork tactile sensor in the present experiment. Its impedance and frequency changes are compared with the value of rubber hardness tester. E//spl rho/ (E: Young's modulus, /spl rho/: density of silicone rubber), and acoustic impedance /spl rho/C (C: sound velocity of longitudinal acoustic wave in silicone rubber). The viscoelastic properties of silicone rubber are also discussed with respect to its impedance change characteristics against /spl rho/C.