Internet-based obstacle avoidance of mobile robot using a force-reflection

The possibility of operating in remote environments by means of teleoperated systems has always been considered of relevant interest in robotics. For this reason, in this paper, the relationship between a slave robot and the uncertain remote environment is proposed as the impedance to generate the virtual force to feed back Io the operator. For the control of a teleoperated mobile robot equipped with camera, the teleoperated mobile robot take pictures of remote environment and sends the visual information back to the operator over the Internet. Because of the limitation of communication bandwidth and narrow view-angles of camera, it is not possible to watch the environment clearly, especially shadow and curved areas. To overcome this problem, the virtual force is generated according to both the distance between the obstacle and robot and the approaching velocity of the obstacle. This virtual force is transferred back to the master over the Internet and the master, which can generate force, enables a human operator to estimate the position of obstacle in the remote environment. By holding this master, in spite of limited visual information, the operator can feel the spatial sense against the remote environment. This force reflection improves the performance of a teleoperated mobile robot significantly.