Some results on sensitivity and robust stability of input-output systems governed by integral and differential equations

Abstract

We consider input-output systems (not necessarily of feedback type) on the time domain [0, ∞) which are governed by nonlinear vector integral or differential equations that relate the input and the output. Assuming that these equations depend on a parameterA, describing perturbations, which is allowed to vary in a vicinity of a nominal valueA0 in a linear space, we study how strongly the output is affected by changes of (a)A0 when the input is fixed (insensitivity), and (b) the input whenA is fixed withAA0 being not too large (robust stability).