摘要
针对某型光纤（FOG）捷联惯组（sINs）的轻量化设计要求，采用了空间五点减振的布局方案。基于弹性中心理论计算了空间五点减振系统的弹性中心和偏心量，在捷联惯组存在质心偏移的情况下，增设第五点减振器可以将减振系统的弹性中心和捷联惯组惯性测量系统质心之间的偏心量减少到1．42mm。从刚体动力学出发对振动耦合的解耦条件进行了讨论，指出捷联惯组在惯性主轴偏移的情况下，空间五点减振系统无法实现角振动的解耦，但是通过调整IMU结构布局的质心，或通过调整减振器的刚度比，都可以实现线振动和角振动的解耦。用有限元方法对上述两种解耦方案下捷联惯组的冲击响应进行了计算，仿真结果表明，调节质心和调整减振器刚度两种方法对于降低IMU振动耦合的效果均较为理想，由线冲击引起的角振动降低了约29—100倍。
Five vibration isolators are installed on the spatial five vertices of rigid body for the light-weight design demand of fiber optical gyroscope （FOG） strapdown inertial navigation system （SINS）. The elastic center and eccentricity of the vibration damping system are calculated based on elastic center theory, and the addictive fifth isolator makes the eccentricity from centroid of Inertial measurement unit to elastic center decrease to 1.42mm. The solution to eliminate coupling vibration is discussed, and the coupling vibration among angular vibrations can＇t be eliminated because there is inertial principal axis excursion, but the coupling vibration between linear and angular vibrations can he eliminated by means of adjusting structure mass distribution or isolators＇ stiffness ratio. The vibration impact response of SINS is calculated by using the finite element method and the results show that both two kinds of optimization methods achieve good vibration decouple effects and angular vibrations caused by linear impaction reduce by about 29 ～ 100 times.
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2015年第9期1030-1035,共6页
Journal of Astronautics
关键词
光纤陀螺
捷联惯组
减振器
振动耦合
Fiber optical gyroscope
Strapdown inential navigation
Isolator
Coupling vibration
