Efficient computation of a guaranteed stability domain for a high-order parameter dependent plant

A practical method based on μ-analysis is proposed in this paper to compute a robustness margin for high-order LTI plants with highly repeated parametric uncertainties. This margin is guaranteed on a continuous frequency interval and there is no risk of missing a critical frequency. The resulting algorithm is then encompassed in a recursive procedure, which computes a guaranteed stability domain for possibly uncertain parameter dependent plants. Several extensions and variations to handle the trade-off between conservatism and computational time are also highlighted. The efficiency of the method is finally demonstrated on a challenging industrial problem: assessing the stability of a flexible passenger aircraft over its entire flight envelope and for all admissible mass configurations.