The purpose of this study is to determine objectively and intuitively to what degree the artificial arm supplied to a user excutes as a proxy for his inherent arm.
A normal person was used as a subject and tasks were performed using the artificial arm and his inherent arm. When the two abilities according to these two kinds of experiments were measured and compared, the personal parameters and environmental conditions included in the abilities test cancelled out and also the ratio of two abilities for a normal person could be assumed to be the ratio of the ability of the artificial arm handled by an amputee to the ability of the inherent arm which is assumed to exist at present, although it has been lost.
The authors have defined and studied the index number of the controlability, ab. ICA, as the ratio of two abilities mentioned above.
Data from tests on a subject taken after an interval of one year in controlling the conventional terminal device with and without sensory feedback device, and from a few subjects who had different degrees of skillfulness in controlling the powered elbow by means of a myo-electric potential, in general, confirm the reproducibility of theICAindex.