带减振器的光纤陀螺惯导系统有限元仿真建模方法

以某光纤陀螺捷联惯导系统的IMU单元为研究对象,利用有限元分析软件包Patran/Nastran建立了含减振器的IMU系统有限元模型。重点介绍了有限元模型中减振器的等效处理方法,比较了模型的随机振动响应计算结果和样机振动试验的实测结果,两者的误差在3.2%以内,证明了有限元建模过程中所使用的减振器等效处理方法的合理性。

Finite Element Modeling Method Based on FOG Inertial Navigation System with Dampers

The inertial measuring unit (IMU) structure of a fibre-optic gyroscope (FOG) strap-down inertial navigation system was studied. After suitable simplification applied to the assembly model of IMU system,the finite element model was built using the finite element analysis (FEA) software Patran/Nastran. The method of dampers-modeling of the IMU system was described, the way how the key parameters of dampers were decided and how they were connected with the IMU structure was introduced. The random response analysis was applied based on the FE model built previously. By comparing the simulation results with the corresponding experiment results, it was indicated that the biggest error between them was less than 3.2%. The method of finite element modeling introduced was proven to be correct and feasible.