| Rigid virtual spacecraft vibration test is needed to ensure the safe of spacecraft. The structure of the spacecraft becomes more and more complex, as a result, the FEM of the spacecraft is not accurate enough. There are more errors between simulation results and experimental data, so FEM updating is needed. Although there are many methods of model updating, up to now, there is little general model updating software because of the model updating software is so poor both home and abroad. So, spacecraft virtual vibration test model updating software with interface to MSC.Patran/MSC.Nastran is developed based on modal optimization and frequency response optimization of sensitivity method.First, the FEM model updating technique based on modal parameters sensitivity method and based on frequency response sensitivity method are deduced in detail. Second, in regard to the complex structure of spacecraft, parameters of FEM are screened through the sensitivity analysis method. Third, according to the ground-based vibration test conditions, the test FRF data divided by transfer function of FEM will be the input load. At last, in order to verify the validity of optimized model, the model correlation are analyzed.The design question of connect procedure and interface about finite element model updating technology and the commercial finite element analysis software have been studied. The model modify software is developed using C++ language in the way of change data with the Patran/Nastran files, and the post-processing program is developed.According to test data, the finite element model of tube structure and vibrating table are modified using the modify software developed in this article, the modified model is verified in the way of compare the finite element analysis frequency response with the test frequency response in different load cases. Final results show that the model updating method and the modify software are valuable in engineering applications.
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