Robust Output Feedback Control For A 3-Dof Helicopter System

In this paper, the problem of robust backstepping control for a three-degree-of-freedom experimental helicopter is investigated by using output feedback. The proposed control strategy can estimate the angular velocity through a state observer and achieve the attitude tracking of the elevation and pitch angles respectively in the case of using only the angular position sensor. The system unmodeled dynamics, parameter uncertainties, and external perturbation are addressed via robust backstepping technique. It's shown by Lyapunov stability analysis that the closed-loop system can be stabilized by the proposed controller with high control accuracy. The experimental results are provided to verify the effectiveness and advantage of the proposed control methodology.