Design of Robust <italic>H_&#x221E;</italic> Guaranteed Cost Controller of Quadrotor UAV for Set-Point Tracking

Abstract

This study proposes a robust $H_{\infty }$ guaranteed cost controller (RHGCC) and its design method for set-point tracking control of quadrotor unmanned aerial vehicle (UAV) considering both model uncertainties and external disturbances. To guarantee a certain level of optimal performance against the effects of model uncertainties and external disturbances such as wind gusts, the proposed RHGCC integrates the $H_{\infty }$ control method with guaranteed cost control. Furthermore, a linear matrix inequality (LMI)-based controller design condition is proposed, guaranteeing not only a certain level of linear quadratic (LQ) cost but also the upper bound of the disturbance attenuation level in terms of $H_{\infty }$ norm. The proposed RHGCC is designed for the position and attitude control of the quadrotor UAV, enabling both the position and attitude of quadrotor UAV to be robust against external disturbances. Simulation results validate the effectiveness of the proposed RHGCC and demonstrate that the proposed method outperforms conventional methods in reducing tracking errors against disturbances. Especially, the proposed method significantly reduces the $H_{\infty }$ norm and suppresses disturbances compared to conventional methods.

Keywords

• Linear matrix inequality
• optimal control
• quadrotor UAV
• robust control
• set-point tracking control