Tele-existence (I): Design and Evaluation of a Visual Display with Sensation of Presence

Summary: The tele-existence system is a teleoperator system that enables a human operator at the controls to perfonn remote manipulation tasks dexterously with the feeling that s/he exists in the slave anthropomorphic robot in the remote environment. The Mechanical Engineering Laboratory has started an 8-year national project of ad­ vanced robotics to realize this tele-existence system. In this paper the project goal is described first. Next, the visual display system that measures the operator's head move­ ment, controls the slave robot's vision system according to the movement, and displays the acquired two visual images to both the operator's eyes through head-mounted CRT displays, whose images in turn fuse to give the visual sensation (which is very natural), when designed and constructed. Evaluation of the system has been carried out by measuring the metric of binocular visual space of a human operator with or without the display device. The experiment reveals that the metric of the binocular visual space viewed with the naked eye can be reserved in tele-existence system by servoing the focal length of the display lenses and the angle of the convergence of the two CRTs appropriately.