Research On Reconstructing The Antenna Structural Deformation Of The Variable Cross-Section Wing With The Strain

In recent years,with the development of aviation industry and electronic information technology,unmanned aerial vehicle(UAV)technology has been rapidly developed.By means of combining the conformal antenna,the aerial warning of UAV can be realized.However,due to the influences of the aircraft gravity and the turbulence airflow,the shape of the wing is changed,which leads to the electrical performance of the wing common carrier antenna decreasing and affects the detection and early warning performances of the UAV.In order to ensure the normal work of the common load antenna,it is necessary to sense the wing deformation in real time to compensate the electrical performance of antenna.Focusing on a certain UAV,basing on the inverse finite element method(IFEM)of the strain measurements and the reconstructing the deformation of the variable cross-section beam,a reconstructing method used to reconstruct the deformations of variable cross-section beam and spatial beam is deduced in this paper.With the above method,the deformation of the UAV wing can be reconstructed in real time.In order to verify the accuracy of reconstructing the wing deformation in the practical application with IFEM,some experiments are performed on the wing sample.In the first part of this paper,the wing is firstly equivalent to a spatial beam structure on the basis of the structural characteristics of the wing,and this spatial beam is combined the constant cross-section beam with the variable cross-section beam.Then,based on the Timoshenko beam,the IFEM of the constant cross-section beam is derived in detail.Lastly,the effect of deformation reconstruction of constant cross-section cantilever circular beam by IFEM is verified with simulation test.In the second part of this paper,in view of the wing is combined the variable cross-section beam with the spatial beam,a research on reconstructing the deformations of the variable cross-section beam and the spatial beam with IFEM is performed.For the deformation reconstruction of the spatial beam,the IFEM model of the spatial beam can be obtained by integrating the element reconstruction model which transferred from the semblable stiffness matrix and semblable loading vector of the local beam element with coordinate transformation.Then,the feasibility of the above model is verified with performing a loading simulation test on a spatial beam structure.Because of the cross-section size of the variable beam is changed gradually,the displacement function and the section strains solving method in the constant cross-section IFEM model are not suited for the variable cross-section beam.The displacement function and the section strains solving method for the variable cross-section beam are deduced from the relationship between the changing function of the variable cross-section size and the element constitutive equations,and then the IFEM model of the variable cross-section beam is developed.The feasibility of the IFEM model for the variable cross-section beam is verified with using a simulation test.Finally,a finite element model of a certain type of wing is established for static loading analysis,and the feasibilities of the above IFEM models of the constant cross-section beam,the variable cross-section beam and the spatial beam are verified with using a simulation test of wing deformation reconstruction.Furthermore,designing and processing a physical model of wing,and some loading tests are performed on the above physical model.The comparisons between the deformation estimated from the strain measurements of the wing surface with using IFEM models and the deformation measured with using the displacement measurement system show that,the IFEM models deduced in this paper can be well applied in the practical implementation.