Discrimination of Particle Diameter by using Tactile Information (Construction of an Artificial System and Comparison with Human Subject Experiment)

Abstract

Humans obtain some tactile feeling when they touch and rub objects with their fingers, which should be associated with some information about the objects. It means tactile information exists in such tribological actions of their fingers inevitably. In the present study, discrimination of particles has been investigated by using tactile information in an artificial system. Two kinds of time-series signals, i.e. normal and tangential fluctuations, were obtained experimentally when two silicone-gum specimens were rubbed with sands between the surfaces of specimens, in which the sands with sizes of 180-710 1.im were classified into five samples by sieves. The particle diameters of samples were found to be correlated with two quantities obtained from the time-series signals ; one was the normal elastic recovery between before and after rubbing, and the other was the weighted mean frequency of dominant elements appearing in the spectrum of tangential fluctuation. By using the relationship between the two quantities and the particle diameters, the artificial system showed an ability of discrimination comparable with human subjects.