Modeling and experimental verification of dynamic characteristics antenna structure under mechanical shock using MDOF model

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2015
Özçelik, Yunus Emre
Antenna structures used in electronic warfare, radar, naval, satellite, spacecraft systems encounter mechanical shock from various sources such as near miss under water explosion, pyrotechnic and ballistic shocks. Since most antenna structures have larger dimension in longitudinal direction and experience high requency, high amplitude shock energy, geometric nonlinearity becomes crucial to predict dynamic behavior in real life. In this thesis, an antenna structure is modeled by Euler-Bernoulli beam theory including geometrical and inertia nonlinearities. The resulting partial differential equations of motions are converted into a set of nonlinear ordinary differential equations (ODEs) by using Galerkin’s Method, which are solved by Newmark and Backward Euler time integration methods. The results for the linear system obtained from time integration and approximate methods such as Absolute Method, Square Root of Sum of Squares (SRSS), Naval Research Method, Combined Quadratic Combination (CQC) and Shock Response Spectrum Method (SRS) are compared to the nonlinear ones. Moreover, these results are compared with the ones obtained from commercial Finite Element software as well as experimental results from a drop test table.

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Citation Formats
Y. E. Özçelik, “Modeling and experimental verification of dynamic characteristics antenna structure under mechanical shock using MDOF model,” M.S. - Master of Science, Middle East Technical University, 2015.