How long does it take to learn trimanual coordination?

Abstract

Supernumerary robotic limbs can act as intelligent prostheses or augment the motion of healthy people to achieve actions which are not possible with only two natural hands. However, as trimanual control is not typical in everyday activities, it is still unknown how different training could influence its acquisition. We conducted an experimental study to evaluate the impact of different forms of trimanual action on training. Two groups of twelve subjects were each trained in virtual reality for five weeks using either a three independent goals task or one dependent goal task. The success of their training was then evaluated by comparing their task performance and motion characteristics between sessions. The results show that subjects dramatically improved their trimanual task performance as a result of training. However, while they showed improved motion efficiency and reduced workload for tasks with multiple independent goals with practice, no such improvement was observed when they trained with the one coordinated goal task.

Comparison of human trimanual performance between independent and dependent multiple-limb training modes

“…The three-hand performance and coordination were improved from based-line session to test session, the improvements are mainly from footcontrolled hand. In addition, the subjects' performance was gradually improved from week to week, but with different learning patterns for two trimanual training tasks, which was investigated in a separated study [29].…”