Approximate controller design for singularly perturbed aircraft systems

Purpose - To design a reduced-order controller with loosing little accuracy. Design/methodology/approach - Singular perturbation approach by quasi-steady state approximation and by Matrix block diagonalization technique is used. Findings - It is shown that few errors occur between the uncorrected and corrected solutions for the fast subsystems while a few errors occur between the two kinds of solutions for the slow subsystems. The uncorrected solution is admissible for most dynamics. If not, it is recommended that the corrected solution be used. Research limitations - Proportional feedback control gain is obtained by Pole placement method, which may produce an unwanted overshoot in the response. Originality/value - This paper shows that the corrected controller is successfully applied in the aircraft dynamics and control.