Abstract
The primary purpose of using a white cane is to be able to detect street conditions and obstacles based on the reverberations and tactile information that is gathered from the tip. But users reported in interviews that used their canes to distinguish between various materials or recognize certain objects. In this study, we investigated the relationship between vibration and sense of hardness using white canes. We measured frequency of vibration of the tip of the cane by acceleration sensor when the cane contacted with rubber board that have 4 hardness levels. And using psychological experiments, we then had participants estimate their sense of hardness for each hardness level. It was found that there is a correlation between the hardness sense and frequency pattern of vibration. This result may become the basic knowledge of indirect tactile perception.
