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With the development of modern agriculture , increasing demand for farm machinery . Requires operating machinery with farming, ditching, ridge system , earth , water , spraying and other functions , but also has small size, light weight , less pollution, noise, walking handy features. And agricultural facilities developed countries, agricultural facilities to adapt our lack of operating machinery products , relevant technical backwardness , high production costs , especially in operator comfort, safety and other aspects of the job situation is particularly prominent behind , which seriously hampered China sustainable development of agricultural facilities . This departure from the ergonomics , the use of modern CAE technology, finite element analysis , optimization, test and analysis techniques combine armrest for small agricultural operations for structural dynamic design and optimization . First, Pro / ENGINEER 3D models created armrest , and the model has been simplified , the simplified model is imported into CAE ??(Patran Nastran) software for modal analysis , the calculated modal parameters freedom armrest ; right kind armrest experimental modal analysis ; comparative finite element analysis and experimental modal analysis results , in order to confirm the correctness of modeling armrest ; finally, the basis of the correct model to optimize the design in order to improve the dynamic characteristics of handrails to in terms of operating comfort improved to better meet ergonomic requirements . Analyze samples for the optimization problem of excessive , proposed the idea of ??using orthogonal design , according to the principle of mechanical product design , the use of structural factors and critical dimensions armrest as experimental design factors and levels , optimized for handrails orthogonal finite element analysis program experimental design and analysis . First determine the critical dimensions armrest with multiple sets of orthogonal experimental design and planning theory of modal analysis test, under the test conditions in each group to get the structure of free modal parameters such as natural frequencies and mode shapes , etc., to extract the corresponding test in each group modes with orthogonal test analysis of the relevant methods, such as visual analysis , variance analysis, to obtain the optimized structure of the handrail , the first natural frequency of the handrail 42.6Hz into 66.866Hz increased 56.96% than the original , to avoid the work of staff sensitive frequency bands , improved ergonomic armrest performance.
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