Finite Element Analysis On Wings Of Flapping-Wing Micro Air Vehicles Based On Dragonfly Wings

Flapping-wing Micro Air Vehicles (FMAV) are new conceptual air vehicles. They surpass the research fields of traditional airplane design and aerodynamics in relation to application technologies, and initiate the applications of MEMS technologies to aviation fields. The design and fabrication of high efficient biomimetic wings with good dynamic characteristics are the keys of FMAV. Meanwhile, it's also a very challenging research topic at present. In this thesis, the finite element method is used to study the static and dynamic characteristics of the biomimetic wings of dragonfly. Based on the results of FEA (finite element analysis), the structure and dynamic performance of biomimetic wings of FMAV are discussed extensively. The modeling and analysis method, as well as the conclusions are helpful to the design, fabrication and application of FMAV.Based on the real structure of the forewing and hindwing of dragonfly, the plane geometric models of biomimetic wings are created using some CAD software. Then the three-dimensional finite element models of biomimetic wings are built by choosing the suitable element types and characteristic parameters. The static and dynamic characteristics of biomimetic wings are studied in this thesis. Through the linear and nonlinear static analysis on the biomimetic wings, the static performance such as deformation and stress distribution are obtained. After comparing the results and changing the material characteristic parameters in the static analysis to see the changes of biomimetic wings, several keys to determine the structure stiffness of biomimetic wings are summarized.Then, the modal analysis of two differently typical biomimetic wings are conducted and their modal parameters as nature frequency and vibration modes are obtained. As a result, the plane-structure wings with shell elements for FMAV is not ideal comparing with the truss-structure wings composed by shell and pipe elements. Based on the dynamic responses of the structures under sinusoidal excitation with several frequencies through transient dynamics analysis, the influence of natural frequency on the vibration characteristics of the biomimetic wings is discussed further more.At last, uniform flow around biomimetic wings is simulated with the...