Controller Synthesis Methodology for Multivariable Nonlinear Systems With Application to Aerospace

Abstract

In this paper, a new systematic controller synthesis methodology for use with highly nonlinear multivariable and nonautonomous systems with application to a class of multivariable nonlinear aerospace systems is presented. The procedure is applied to a typical liquid propellant engine, and the performance of the resulting new control system is presented. In this research, the nonlinear dynamic model of the engine, which includes both soft and hard nonlinearities, is developed. The systematic controller design procedure is based on describing function models of the engine coupled with a new multivariable exact model matching procedure.

Application of describing function technique to idle speed control

“…(See Appendix for nomenclature) This objective function is also used in engine propulsion control as demonstrated in [22]. 4.…”

“…In order to design 11 c and 22 c , any available technique in linear control theory may be utilized. In this research, the developed controller cad _ [25] Matlab function is used (a copy of this function may be requested from the second author by sending an email).…”

“…In 1983, a new platform for design of classical nonlinear feedback control systems based on one, two, or more than two describing function models of the plant was introduced [16]. That platform has been applied to design robust nonlinear feedback systems in robotics and aerospace industries (e.g., [15], [17][18][19][20][21] and references therein). In this research, a new implementation of this design platform to automobile idle speed control problem is investigated for the first time.…”

Model Based Adaptive Piecewise Linear Controller for Complicated Control Systems

“…It is determined by the filtered command tracking errors. Nonlinear controller's syntheses using inverse describing function for use with hard nonlinear system have developed for several researchers [11][12][13]. They are complicated but effective for nonlinear systems.…”

Idle speed control using a describing-function approach

“…In 1983, a new platform for design of classical non-linear feedback control systems based on one, two, or more than two describingfunction models of the plant was introduced [16]. That platform has enjoyed considerable success in designing robust non-linear feedback systems in the robotics and aerospace industries (see, for example, references [15] and [17] to [22], and references therein). In this research, application of this design platform to the idle speed control problem is investigated for the first time.…”