捷联惯组减振系统角振动、线振动共振频率理论分析

Theory analysis on resonance frequencies of linear vibration and torsional vibration of strapdown IMU damping system

当前实际工程中,角振动试验技术和设备尚不成熟。以指导捷联惯组减振系统设计过程为目的,结合捷联惯性组合减振系统对角共振频率的特殊要求,对线振动、角振动共振频率的关系进行了分析与讨论。建立了捷联惯性组合减振系统的动力学模型,得到了捷联惯组减振系统数学模型,利用刚体动力学方法分析捷联惯组的转动惯量和回转半径,得出理想情况下捷联惯性组合减振系统线共振、角共振频率存在一定的比例关系,并与减振器安装中心到转动中心线的平均距离和惯组回转半径有关的结论。最后讨论了改变减振系统刚度和减振器布置方式两种改变共振频率的方法,并对两种方法进行了比较。

The technique and device for torsional vibration test is not yet mature. In order to guide the design of damping system, we analyze and discuss the relationship of resonance frequencies between linear vibration and torsional vibration for the special require of strapdown IMU damping system. We gets the mathematic model by establishing the dynamic model of strapdown IMU damping system, and analyzes the moment of inertia and the radii of gyration of strapdown IMU by rigid body dynamics theory. The result shows that the strapdown IMU linear vibration and torsional vibration resonance frequency is a proportional relation when perfect condition is gained, which is concerned with the radii of gyration and the distance between the center of damping and the line of turn. Finally, we discuss the methods of changing the rigidity of shock absorber and setting the shock absorber, and compare the two methods.