Helicopter flight control system design

The purpose of this paper is to design helicopter flight control system and improve its stability, maneuverability, and agility. Firstly, the linearized mathematical model of a helicopter is established from the nonlinear dynamic equations with six degrees of freedom . Then, modern linear control theory, such as linear quadratic regulator (LQR), and H_∞ theory, are applied to the linearized model of the helicopter to design closed-loop flight control system. The linear controller is then used in the nonlinear model of a helicopter to simulate nonlinear dynamic response, and to compare flight quality of different flight control designs.