Passive teleoperation control with varying time delay

This paper is devoted to the passivity based control in force reflecting bilateral teleoperation for varying time communication delay. In order to improve the stability and task performance, master and slave in bilateral teleoperation must be coupled dynamically via the transmission network through which the force and velocity are communicated. However, time delay, caused by varies factors such as transmission distance, network congestion, and communication bandwidth, is a long standing impediment to bilateral control and can destabilize the system evidently. In this paper, we investigate how the varying time delay affects the advanced teleoperation stability and results in an out-of-control status. A new optimal adaptive approach based on passivity control has been bilaterally designed for both the master and slave sites, in which extra variables will be transmitted together with the wave variables in the scattering system. In the proposed scheme, we achieve not only a passive control but acceptable tracking performance and the tracking performance will verify this approach