ANALYSIS OF REACHING MOVEMENTS WITH THE ADDITION OF RESISTANCE FORCES IN THE HORIZONTAL AND VERTICAL PLANES USING A ROBOT ARM IN NON-DISABLED INDIVIDUALS

摘要

A new, simpler, quantitative evaluation method, with higher reproducibility and validity than the conventional method used to evaluate hemiplegic upper extremities, is needed. The general properties of reaching movements were examined in healthy subjects by adding resistance forces to establish a new evaluation method using robotic technology. The subjects included 14 non-disabled males and 2 non-disabled females whose average age was 25 years. Their reaching movements were measured in both the horizontal and vertical planes with resistance force to add disturbance using a robot arm. Then, the jerk cost, the largest swinging distance, and the end¬point displacement were calculated. Significant differences were seen between subjects with and without disturbance in the horizontal jerk cost and largest swinging distance in the horizontal plane, and vertical jerk cost and largest swinging distance in the vertical plane. The horizontal and vertical jerk costs and largest swinging distances were also greater with a larger disturbance. In the reaching movements of healthy people in the horizontal and vertical planes, when the reaching movement was subjected to orthogonal disturbance, jerk cost and largest swinging distance in the direction of the disturbance were easily affected in response to the disturbance.