Shadow and Mirror Mode Bilateral Control for a Tele-Operated Robot System

Abstract

This paper proposes the development of haptic robot system for rehabilitation exercises. Recently, haptic communication is widely applied in a robot system for sensing the force between robot and human operator. The bilateral control which consists of master and slave robot is used to transfer and receive action/ reaction force and position information. In this paper, the controlling of robot has been designed by considering the specification requirements of user. This master-slave robot system can be controlled by two different approaches: 1) by using the shadow mode and 2) by using the mirror mode. In the force control designed, such force sensor can use to measure the external force. It is shown that the reaction force response can be controlled. However, the problem of sensor noise and bandwidth are deteriorated the performance not only at the master or slave side but also at the whole control system. Thus, disturbance observer (DOB) has been proposed and used instead of force sensor for improve the performance and robustness of the whole system. In this study, the shadow and mirror mode of bilateral control is used with the master-slave robot for rehabilitation exercise. On the shadow mode slave robot is controlled according to the master robot like a shadow while mirror mode, slave robot has moved in the opposite direction like a reflection image. The results of each mode are represented in an experimental result. By using the proposed robot system, it is possible to apply in the rehabilitation process.