Handling quality characterization of flight systems controller gains

This paper shows how to cast the classical flight control system design into the framework of modern robust control theory by using Guardian Maps. A design procedure is proposed which consists in characterizing all control gain parameters such that the resulting close-loop poles all lie within a specific desired region. This region is obtained by projecting the boundaries of several types of handling qualities into the complex s-plane. A multivariable polynomial in the gains is then obtained such that any set of gains for which this polynomial is nonzero is guaranteed to place the closed-loop poles in the desired handling quality region. An example of longitudinal flight control system design is presented, which shows the efficiency of the proposed method.