Height and attitude tracking control of an unmanned helicopter via a HDOB-backstepping composite control method

Abstract

This study studies the height and attitude tracking control problem of an unmanned helicopter system with disturbances. A composite controller based on the combination of harmonic disturbance observers and backstepping technique is proposed to achieve asymptotic tracking for height and attitude. Firstly, harmonic disturbance observers (HDOB) are designed to estimate the unknown disturbances affecting each channel. Then, a composite controller is proposed by integrating the backstepping control technique and the HDOB technique together to achieve the height and attitude tracking goal. Stability analysis of the closed-loop system is given. Finally, numerical simulations are presented to verify the efficiency of the proposed control scheme.

Keywords

• closed loop systems
• adaptive control
• nonlinear control systems
• control nonlinearities
• observers
• lyapunov methods
• helicopters
• uncertain systems
• attitude control
• robust control
• stability
• control system synthesis
• unknown disturbances
• composite controller
• attitude tracking goal
• hdob-backstepping composite control method
• attitude tracking control problem
• unmanned helicopter system
• harmonic disturbance observers
• backstepping technique
• asymptotic tracking