The primary purpose of gust alleviation design is to achieve a lighter aircraft structure by reducing internal loads. Currently, the input signals for controllers often use wingtip and fuselage acceleration signals, which are correlated with the internal loads in the wing structure, but not directly reflect their magnitude. This paper proposes a feedback strategy that directly utilizes internal loads measurements by replacing the wingtip acceleration signal with the wing root bending moment signal as the control input to establish a robust \({\text{H}}_{\infty }\) controller. A structural dynamic model and an unsteady aerodynamic model of a flying wing configuration aircraft were developed based on the finite element method and the dipole lattice method. The aeroelastic equations considering pitch degree of freedom under gust response were derived, and the open-loop gust response was calculated based on these aeroelastic equations. Building upon the open-loop gust response analysis, robust \({\text{H}}_{\infty }\) controllers were designed based on the wing root bending moment signal, the wingtip acceleration signal, and a coupled signal combining both the wing root bending moment and wingtip acceleration signals. Simulations compared the alleviation effects of controllers using different control inputs. The results show that the controller based on the wing root bending moment signal achieves better gust alleviation compared to the controller based on wingtip and fuselage acceleration signals. Moreover, its alleviation effect remains significant across different flight speeds and various gust conditions.
