Measurement of Distance Error in Reaching Movement of the Human Hand without Using Vision

This paper deliberates the spatial cognitive ability of the moving distance of the human hand, which is measured by using motion capture. Before the movement begins, the subject is shown a standard length. Then, both horizontal and vertical blindfold hand movements were measured using the proposed protocol for six right handed subjects in order to investigate the cognitive ability of the moving distance of the human hand. The experimental results show that the average moving distances obtained in both directions were quite smaller than the standard length; an inverse ";V"; pattern in percentage result was observed only in the horizontal movement. The experimental result also demonstrated an interesting relationship between the hand moving distance and manipulability of the upper limb.