A Rapid Evaluation Method for Flying Quality

In order to solve the problem that the higher-order system is difficult to obtain accurately and the initial parameters of equivalent matching are difficult to determine leading to matching failure or long computation time, when applying equivalent matching in flying quality evaluation, this paper proposes a method for rapid evaluation of flying quality. In this method, the sine-sweep is used to obtain the discrete frequency points of the system output and fit a preliminary low-order model. The pattern search method (PSM) is adopted and the parameters of the preliminary low-order model are used as the initial value of the frequency domain matching to obtain the low-order equivalent system. If the mismatch degree between the low-order equivalent system and the high-order system in the step response is greater than one-tenth of the frequency domain mismatch degree, the PSM is used to perform a double match in the frequency and time domains. The final low-order equivalent system is used to evaluate the longitudinal and lateral flying quality of the aircraft. It is shown by the simulation results that the system matching is well-matched by this method and the computational time is greatly reduced.