Abstract
A slip sensor using a conventional pressure gauge is developed to realize a robot hand which is capable to hold soft objects, such as a paper cup, pudding, etc. The slip sensor consists of an acrylic block with a cylindrical hole, of which one end is shielded with a rubber sheet and a pressure gauge is mounted on the other end. Water is filled in the hole with a little higher pressure than the atmospheric to swell out the rubber membrane. The movement of an object which contacts with the membrane makes stick-slip vibration and in consequence it makes an impulsive pressure change of the water, superimposed on the static pressure. By observing the impulsive pressure changes detected by a pressure gauge, a slip of a smooth acrylic surface by the velocity of 2.5mm/s against the membrane could be detected. A robot hand using this slip sensor could hold a paper cup with time varying water content, soya bean pudding, etc.
