Disturbance observer design for electric aerodynamic load simulator

Disturbance-observer (DOB)-based controller design is one of the most commonly used methods in the field of servo control. In this paper, an advanced DOB design method is proposed, and the applied to the electric aerodynamic load simulator (EALS) for rejection of disturbance from rudder´s active motion. The mixed sensitivity optimization problem, which is the main issue of DOB design, is also solved through the parameterization of DOB. Different from conventional methods, the Q-filter is separated from the mixed sensitivity optimization problem. A systematic design law for the DOB is proposed. The approach in this paper guarantees the robustness and optimality of the DOB and enables the design for unstable plants. Experimental results have proved the effectiveness of proposed method.