On μ-analysis and synthesis for systems subject to real uncertainty

The paper introduces a new approach for the computation of a lower bound on the structured singular value (SSV), μ in the presence of purely real and mixed/complex uncertainties. The approach utilises a frequency sweeping technique based on a linear fractional transformation representation of structured uncertainty. The technique is applied to a well-known civil transport aircraft example. A fixed structure controller synthesis strategy is developed, which addresses potential stability problems that can occur using standard design methodologies.