柔らかい力覚センサの開発 : 第1報,センサの構造と基本特性

This paper presents a study of the characteristics of a soft sensor that has the sense of human skin. The sensor is composed of two rectangular rubber sheets and a strain gauge inserted between the interface of the two sheets. The sensor is an application of Poisson's effect, which is a peculiar characteristic of the elastic medium. The normal force applied to the surface of the sensor contracts the rubber sheets in the normal direction. At the same time, the force expands the medium in the horizontal direction, which results in a horizontal strain proportional to the normal force applied. Thus, the magnitude of the applied force can be determined by measuring the output of the strain gauge that is placed horizontally between the rubber sheets. Characteristics of the sensor are measured for various combination of the two rubber sheets with different hardness and thickness. It is shown that the soft sensor proposed is effective for measurement of both concentrated and distributed applied loads. Further more, it is found that the hysteretic loop of the stress-strain curve is reduced and the linearity of the sensor is improved by placing copper foil between the two rubber sheets.