Adaptive feedback linearization control for twin rotor multiple-input multiple-output system

Abstract

This paper deals with the tracking problem of a twin rotor multiple-input multiple-output system (TRMS) described by an Euler-Lagrange forced model with constant uncertain parameters and input disturbances. The control of TRMS system is the benchmark problem for control of helicopter which has been a challenging problem due to flexible dynamics, nonlinearities and cross coupling. The control objective is to make this systems track to the given trajectories accurately in spite of the influences of uncertainties and input disturbances. We propose the adaptive feedback linearization controller by using 03 adaptive parameters that stand for the unknown mass parameters of parts in the TRMS. By choosing appropriately controller parameters, the effects of the input disturbances that are friction, cable, gyro moments and the effects caused by the main propeller speed and the tail propeller speed on the vertical and horizontal movements to the yaw and pitch angles will be attenuated. Two functions, including unknown mass parameter adaption and the disturbances attenuation to guarantee the errors of the pitch and yaw angles, are implemented simultaneously by the adaptive feedback linearization controller. The simulation and experimental results show that the good robustness of the TRMS controlled by the proposed controller can be obtained arbitrarily.