C*モデル規範型適応飛行制御系

抄録

In this paper, model reference adaptive control systems (MRACS) theory is applied to the design of an aircraft control augmentation system. The most attractive feature of MRACS over other adaptive control systems is that a parameter identification mechanism is not required at all. The problem considered here is to have the aircraft output c_p^* follow a model (c^* model) output c_m^*, where the model is defined to meet a new handling qualities criterion, namely, c^* criterion.
First, an error equation of motion is derived from the model and aircraft equations. Then, the stability of the above error equation system is confirmed by LIAPUNOV'S direct method and the KALMAN-YACUBOVICH Lemma. The block diagram obtained in this manner contains the second order c^* model, seven adaptive gains (variable) and three state variable filters which were employed by MONOPOLI to avoid error derivatives. The adaptive gain scheme is somewhat analogous to the well-known P-I type controller used in many classical applications. The adaptive control law employs the proportional plus integral of the product of the error and other signals which are filter outputs, plant output c_p^*, elevator deflection, etc.
A digital computer simulation was performed at three flight conditions. The result proved that the present system has a great adaptability and that the c_p^* responses are satisfactory. However, normal acceleration response n_z is poor at low airspeed, which fact indicates that c^* criterion is not necessarily complete.