Design And Dynamics Analysis Of Wing Of Piezoelectric Flapping Wing Micro Air Vehicle

Bionic and aerodynamic theory of maturation promotes the micro-flapping-wing aircraft research.According to the fluttering characteristics of micro flapping wing aircraft,researchers wanted to use piezoelectric element as wing drives.Piezoelectric elements have the advantages of high power density and high response frequency,but the displacement of the piezoelectric actuator is small,it is difficult to directly achieve a wide range of wings flapping.In order to achieve wings more substantial flapping,the current success of a method is using a flexible hinge to amplify the displacement of the piezoelectric actuator to enlarge the wing to achieve a more substantial film.But the structure is more complex,driving efficiency is not high.In this paper,the research on the flight of micro-flapping wing aircraft is carried out by using piezoelectric drive directly.According to the requirements of flight and drive,the structure of the bionic wing is improved and the relevant dynamic analysis is carried out.In order to realize the flapping of wings,the paper cooperates to improve the performance of piezoelectric materials and realize the large piezoelectric deformation.The paper combines with the structure of piezoelectric bimorphs and the principle of resonance excitation amplification,and based on the research experience and processing technology of piezoelectric,we design a driving structure of a piezoelectric bimorph.The wings are used as the intermediate layer of the bimorph,and the design requirements for the wing are proposed.The paper adopts the wing structure of imitation dragonfly,which is made up of wing veins and wing film.The main bearing structure of the wing veins as the wing in the flutter process.In order to reduce the quality of wing veins,we simplified the structure of the wing veins and verified the structural characteristics of the reduced wing by means of static analysis and modal analysis.The paper further analyzes the aerodynamic performance of the wing under the action of the piezoelectric actuator.First of all,we give the piezoelectric ceramic and wing of the assembly structure,and according to the piezoelectric dual-chip drive principle to determine the size of the driving force.Then we analyze the structure by transient dynamics.In order to achieve resonance amplification,the first-order nature frequency of the force should be equal to the structure of the wing,the displacement of the wing tip in the direction perpendicular to the wing direction is obtained.Together to get the wing of the flutter of the law.Using the UDF custom function in Fluent,aerodynamic analysis of the flapping of the wing under the drive structure,we get the change of the flow field around the wing in a flutter cycle,and verify the mechanism of the high lift of the insect-"no stall mechanism".Finally,the influence of initial flutter angle,flutter amplitude and flutter frequency on aerodynamic force is analyzed,which provides a reference for the driving signal applied by the flutter experiment of the aircraft and gives the direction for the optimization of the wing after the experiment.