Performance comparison of yaw rate damping controllers

Abstract

Maintaining desired flight conditions in flight envelope for a long period is one of the primary control problems in aircraft flight control. Aircraft dynamics are in general nonlinear, time varying and uncertain. A control system (classical control systems) designed for a flight condition, may not provide the desired stability and performance characteristics in case of deviation from the equilibrium point. There are numerous studies regarding flight control in the literature. Most of the applications about the design of fuzzy flight control are in simulation level. Fuzzy logic controllers (FLCs) from their inception have demonstrated a vast range of applicability to processes where the plant transfer function is not defined but the control action can be described in terms of linguistic variables. Fuzzy controllers are also being used to improve the performance of a system where the plant transfer function is known. Most of the applications about the design of fuzzy flight control are in simulation level. In this study, the results of fuzzy PD and classical PD controller for the yaw damper system is compared and evaluated for a very large four engined passenger jet aircraft in a MATLAB coded program