HUMAN CONTROL OF ROBOTIC MOVEMENT.

Movement times were measured for both hand movements and remotely controlled robotic arm movements. It was found that both can be well fitted by functions derived from Fitts law in which movement time is a logarithmic function of the ratio of movement distance to target size. However, while the number of body joints involved in the task (or the direction of the movement) did not affect the function in the hand movement, the number of axes involved in the robotic movement did affect the movement time function: movement time increased as the number of axes that had to be controlled increased.