Application of Stochastic Zero-Order Output-Feedback to Flight Control Systems

We consider the problem of zero-order output feedback control for retarded state-multiplicative stochastic systems. The delay appears in the system states where the stochastic noise multiplies both the delayed and non-delayed states. A solution is found for the nominal case where all the system matrices are fixed, resulting in a tractable LMI condition. Re-shaping the latter LMI condition to an equivalent inequality enables us to solve the robust zero-output feedback control for the uncertain polytopic case, via the application of a special version of the Finsler lemma. A solvable set of LMIs is obtained for the robust case that depends on only two tuning parameters. The presented theory is applied to a real control engineering problem taken from the field of aircraft control where the pitch control of the F4E aircraft is obtained for some special conditions.