Abstract
Based on the research of sweep and reverse angle deformation laws of the elbow and hand wing sections during the flight of large birds, a multi-section variable-sweep wing structure adapted to large-size UAVs is proposed in this paper. The feasibility of the centroid self-trim compensation morphing process by using collaborative deformation of inner and outer sections is ex-plored. Firstly, a calculation and evaluation method of the driving moment required for morphing based on the vortex lattice method is established. Then, five preselection models with different span ratios of the inner and outer sections of the multi-section variable sweep-wing UAV are constructed. Finally, from the aspects of static stability margin, changes in aerodynamic characteristics, and performance requirements of the drivers during the collaborative morphing process, the influence of multi-parameters on the comprehensive performance of the multi-section morphing wing is analyzed, and the reasonable design range of the span ratio of the inner and outer wing sections of the research object is given. The results show that the multi-section morphing wing proposed in this paper has a significant advantage in solving the problems of drastic changes in aerodynamic, dynamic, and operational characteristics caused by large-size wing morphing. The maximum output power requirement of the drivers in the symmetrical self-trim compensation morphing process can be reduced by increasing the ratio of the inner wing section to the preselected model, and the efficiency of the driver can be improved. The preselection model of the multi-section variable swept-wing UAV with optimal driving moment performance is determined by the comprehensive analysis results, and the corresponding span ratio of the inner and outer wing sections in the morphing sections is about 64.03% and 35.97%, respectively.