Stability and transparency in bilateral teleoperation

Tools for analyzing teleoperation system performance and stability when communication delays are present are presented. A general multivariable system architecture is utilized which includes all four types of data transmission between master and slave: force and position in both directions. It is shown that the proper use of all four channels is of critical importance in achieving high-performance telepresence in the sense of accurate transmission of task impedances to the operator. It is also shown that transparency and robust stability (passivity) are conflicting design goals in teleoperation systems. Achieved transparency and stability properties of two common architectures, as well as a `passivated´ approach and a novel `transparency optimized´ architecture, are quantitatively compared on one-degree-of-freedom examples