Synthesis of discrete time adaptive flight control system using nonlinear model matching

Abstract

Until now, various model matching systems have been proposed for linear systems, but very little has been done for nonlinear systems. The authors have already proposed a design method of discrete time flight control system using nonlinear model matching, but the case of a plant with variable plant parameters has not been considered. In this paper, a design method of discrete time adaptive flight control system using nonlinear model matching is proposed. This method is based on Hirschom's algorithm and facilitates easy determination of the control law using the relationship, between the output and the input, which is obtained by the time shift signals of the output. Also as a result, this method is an extension of the linear model matching control system proposed by Wolovich, in which the control law is obtained by left-multiplying the output by the interactor matrix. The plant parameters are identified by least mean squares method with the observable state variable signals and the control input signals. At the end of paper, the proposed control system is applied to CCV flight control system of an aircraft and the feasibility of the proposed approach is shown by the numerical simulations.