Aerodynamic Nonlinear Modeling and Body-Freedom Flutter Suppression of Flying-Wing Aircraft

To address the body-freedom flutter problem in flying-wing vehicles, an active flutter suppression method with high robustness is crucial. This paper proposes an active flutter suppression scheme based on robust control theory to solve the problem of body-degree-of-freedom flutter suppression for flying-wing aircraft. First, a new aeroservoelastic modeling framework for flying-wing aircraft is proposed. By improving the vortex lattice method and introducing the aerodynamic nonlinear effect into the aerodynamic calculation part of the model, the accuracy of flutter velocity calculation has been improved. Then, a robust active flutter suppression method based on loop-shaping theory is proposed using this model, which avoids the coupling between the controller input and the high- and low-frequency dynamics by optimizing the design of the generalized system, and improves the design of weighting factors, thus reducing the difficulty of parameter tuning. Finally, the stability and robustness of the closed-loop system are analyzed through time-domain and frequency-domain experiments. The simulation results show that the proposed control method can significantly improve the flutter velocity boundary of the flying-wing aircraft, while maintaining sufficient stability margin and strong robustness.