陀螺仪安装支架的动态特性分析与优化

Dynamic characteristic analysis and structural optimization of gyro's bracket

陀螺仪是惯性导航系统的关键部件,其安装支架的动态特性直接影响陀螺仪的测量精度。文中利用ANSYS软件建立了陀螺仪安装支架的三维实体模型及有限元模型,分析了陀螺仪安装支架自由状态下的模态。结合模态分析结果,讨论了陀螺仪抖动的激励和发动机激励对陀螺仪安装支架动态特性的影响,发现了安装支架结构设计的不足,并提出改进方案。理论模态和实验模态分析表明,改进后的陀螺仪安装支架的结构动态特性明显改善。经试验测试,激光陀螺仪输出精度符合惯性导航系统的要求。

The laser gyro is key component of an inertial navigation system,and the dynamic characteristics of its mounting bracket has direct impact on the accurracy of gyro output.The 3D model and finite element model of laser gyro bracket were established with ANSYS software,and the modal analysis was done.Based on the modal analysis results,we studied the influence of the excitation from engine and gyro vibration on the bracket,detected the defect in design of bracket and came up with improvement method.Both theoretical and experimental modal analysis indicated that the dynamic structural characteristic of bracket was significantly improved after modification.Besides,field experiment shows the accuracy of laser gyro output met the requirement of inertial navigation system.