Study On The Bionic Lightweight Design Of The Rudder Wing Structure And Its Mechanical Performance

The rudder wing structure is one of the main load-bearing parts in air vehicle,mainly including the skin and skeleton,and it is of great significance for improving the flying performance to develop new rudder wing with light weight and high strength.However,the conventional design and preparation methods have been unable to meet the practical requirements of projects,new solutions are in urgent need.Recent studies show that the beetle's wing is a typical lightweight lamellar structure with features like high strength,high stiffness and good resistance to damage.Moreover,the animal bones attract majority of engineers due to the characteristics of light weight,high strength and good toughness.Therefore,these two biological structures are selected as the bionic design template to inspire the lightweight and optimization design of rudder wing.Based on metal 3D printing technology,the integrated molding of the complicated structures is achieved,which provides new methods and ideas for the design of new rudder wing structure.A new lightweight sandwich structure is designed,which is inspired by the micro-structure of the cross-section of the beetle's elytra.Other two sandwich structures are selected for comparison.Finite elements analysis of the compression,three-point bending and shear are conducted and the results show that the designed bio-inspired lightweight sandwich structure has a better comprehensive mechanical performance.Samples of three kinds of the sandwich structures are prepared through metal 3D printing.Tests of compression and three-bending are conducted.It turns out that the bio-inspired lightweight structure has a better mechanical performance,which is consistent with the results of finite element analysis.The parametric optimization model of the bio-inspired lightweight structure is established.The optimal parameters of the structure are determined with the goals of multi-objective optimization of mass,maximum equivalent stress and maximum deformation.And all of the three objectives are improved after optimization.The optimized bio-inspired lightweight sandwich structure is used in the design of the rudder wing's skin.Model of the rudder wing is set up,and the topology design of the skeleton is conducted,along with the innovative design of the skeleton with the structural bio-inspired design method.Results of the finite element analysis of the skeleton indicate that the optimized skeleton can reach the requirements of loads and lightweight design.In order to realize the printing of the structure's skin and skeleton as a whole part,skeleton structure is redesigned according to the requirements of metal 3D printing technology.One candidate solution is selected as the optimal improvement out of three by finite element analysis.Finally,it comes true that the rudder wing's skin and skeleton are printed as a whole part using metal 3D printing technology,which establishes a good foundation for further research.