A toolbox for computing the stability margin of uncertain systems

A Matlab toolbox implemented for the computation of the stability margin of uncertain systems affected by structured perturbations is presented. The linear time-invariant systems that can be considered depend on continuously and nonlinearly by uncertain parameters. The proposed algorithm computes the stability margin as the maximal l∞ domain in the parameter space compatible with stability. At the core of this algorithm there is an interval procedure to check positivity on an annular domain centered on the nominal parameter vector. An example of the use of the toolbox is included.