Dynamic observer‐based <i>H</i> ∞ robust control for a ducted coaxial‐rotor UAV
Chang Xu, Chengzhi Su
Abstract
Abstract This paper is concerned with the problem of aerodynamic modelling and robust attitude control for a novel ducted coaxial‐rotor UAV (DCUAV) with time‐varying model uncertainties and external disturbances. In order to achieve robust attitude stabilization and tracking control for the highly non‐linear and coupled system of the DCUAV, a united dynamic observer (DO) based control design is proposed, which can deal with the uncertainty and disturbance simultaneously without estimating and compensating them during the design problem. Through the combination of the theory and the DO technique, the developed control method can achieve a better performance and more accurate tracking control compared with the existing statice observer‐based control design approaches. In addition, the parameterization of the proposed controller is derived from the solution of new LMI formulations based on the transformation of the algebraic constraint. By combining the designed DO‐based controller with the linearized DCUAV system that includes model uncertainties and disturbances, better robustness and tracking performance has been achieved. Simulation results are carried out to demonstrate the efficiency and good performance of the proposed control design.