Coupling control design for the lateral system of lifting body airerafts based on the sliding mode disturbanee observer

For large lifting body plane symmetric aircrafts, lateral maneuvering near the target may cause severe aerodynamic coupling between the lateral channels, possibly resulting in instability of the rolling channel. Aiming at this kind of coupling problem, the lateral system is decomposed based on the singular perturbation theory, and the cascade model of the inner and the outer loops is established. The outer loop is used as an example to design the sliding mode (SM) control law, and the stability of the closed-loop system is analyzed. The sliding mode disturbance observer (SMDO) is also employed to estimate and compensate for the coupling term and improves the robustness of the rolling channel against the lateral coupling. Simulation results show that the designed controller has good dynamic characteristics and anti-disturbance ability, improving the robustness and performance of the control system.