Abstract
A model-based system to implement force-feedback based teleoperation with long time delay is presented. Such a system usually requires a precise model of the real world. However, the precise model is difficult to be realized; the system should be designed with some robustness against errors. In this paper, we propose a model-based space teleoperation system with robustness against geometrical modeling errors. The system consists of a master arm, a slave arm, and a virtual arm which are controlled independently by velocity command. Each arm has autonomy to switch between force and velocity control for contact and non-contact modes, respectively. The operator can feel contact force reflected from the virtual arm. The slave arm realizes the commanded force and, consequently, safe operation is guaranteed. By using a master arm without backdrivability and with high gear ratio, the operator can feel hard contact very well. The experimental results show that a sample ORU task and a door opening task can be realized very effectively, in spite of the long time delay.
