Uncertainty Classification for Rotor-AMB Systems

In this paper, we adopt the gap metric tool to analyze uncertainty propagation in rotor-AMB systems. Of special interest is the effect of open loop plant uncertainties on the closed-loop stability. The results indicate that robustness property under general feedback varies with different sources of uncertainty, i.e., some uncertainties can be easily sup-pressed by any stabilizing controller, while other uncertainties can be amplified. As a result, uncertainty can be classified according to its effect on the closed-loop robustness. From design and analysis perspective, some uncertainties can be effectively approximated or even neglected while others must be accurately modeled, and addressed explicitly in the design and analysis.