Hardware in the Loop Experimental Study of 3-DOF Helicopter

A helicopter flight control system is a typical multi-input, multi-output system with strong channel-coupling and nonlinear characteristics. In order to cope with the problems encountered in current controller design, three control methods including H2 control, Hinf control and mix H2/Hinf control for regulation and tracking problem of a 3-Degree-of-Freedom (3-DOF) helicopter are presented. By analyzing the helicopter system, a state-space representation of the system is established according to the characteristics of each degree-of-freedom motion. Then we designed the H2 controller, Hinf controller and mix H2/Hinf controller, and implemented these controllers by using MATLAB LMI toolbox. All these three control methods are discussed and compared with each other. Numerical study of the three controllers for tracking of a 3-DOF helicopter are conducted, and a hardware-in-the-loop experimental study of the three controllers of the 3-DOF helicopter is made for regulation and tracking problem. To analyze the robust performances of helicopter control system, an Active Mass Disturbance System interference is considered. Numerical simulation and HIL experimental studies show that H2 control is valid and has a satisfactory performance for a 3-DOF helicopter and the Hinf control could increase the robustness of the 3 DOF helicopter system while the mix H2/Hinf control has the both advantages of the H2 and H
^∞
controller.