Synchronism evaluation of multi-DOF motion-copying system for motion training

Recently, motion control strategies that deal with position and force information simultaneously are attraction attention for human support. Acceleration control is one of the candidates for realizing position control and force control simultaneously. In this paper, the motion-copying system based on acceleration control is in focus. The motion-copying system is the system which stores human motion, by storing the postion and force information of the human motion. The motion-copying system is expected to be applied to systems in various fields, such as medical surgery robots as well as robots used to train skills. However, the convetional motion-copying system struggles with the problem of losing robustness in the motion-reproduction phase, especially under external disturbances. In this paper, a novel control strategy of motion-copying system which assures robustness under external disturbance is introduced. By using the proposed method, the motion-reproduction system will be able to reproduce the stored motion accurately, even when a trainee is holding on to the system and applying the external force to the system. This system enables a trainee to acquire the stored skills, using both the visual and the haptic sense. Validity of the proposed method is verified through experimental results.