Effects of Localized Vibration on the Ability of Discrimination for the Difference of Surface Roughness through Tactile Sense
In this paper, the localized vibration that was one of the environment in measurement was taken up and the effect of it on the organic functions of the tactile sense for surface roughness was examined. This effect was evaluated by the ratio of the ability of discrimination in the tactile sense at the finger tip which was exposed to vibration to the ability of discrimination in the tactile sense which was not exposed to vibration. The ability of discrimination for surface roughness by the tactile sense at the finger tip exposed to localized vibration was considered by the catastrophe model. Discriminating the difference of surface roughness through tactile sense of finger tip exposed to localized vibration, the judgement gets dipersive as the increase of acceleration amplitude. For the purpose of analysing this phenomena quantitatively, stochastic cusp catastrophe model was applied. As a results, it is confirmed that this phenomena can be explained by cusp catastrophe model quantitatively. Next, the effect of localized vibration on human body was clarified in the view point of workability and the phenomena in which the sensibility of tactile sense becomes dull were taken up here. A tactile sensory test for surface roughness was performed after localized vibration exposure, and the change of organic function of tactile sense for surface roughness was investigated. The decrement of discrimination ability for surface roughness occurs by giving localized vibration. However, it is recovered about twenty minutes later after the stimulus.