惯性积对光电设备减振性能的影响

Influence of Inertia Product on Vibration Isolation Performance of Photoelectronic Equipment

在机动平台上一般采用被动减振系统来保护光电设备,设备的惯性积直接影响着减振系统的动力学特性和幅频响应特性,引起对应两角振动的耦合。为了定量确定惯性积的影响,根据动力学理论建立了系统的六自由度动力学模型并简化为两自由度模型,利用无量纲化方法,推导了固有频率与惯性积之间的数学关系,分析了在不同惯性积下系统的幅频响应。结果表明,系统的两阶固有频率随惯性积分别单调递增和单调递减,并且在惯性积为零处差值最小;系统对应的两阶固有频率差值随惯性积单调递增,在惯性积为零处最小;在低阶模态方向,惯性耦合系统的减振性能优于无耦合系统。

The passive vibration isolation system is generally used to protect the photoelectric equipment on the mobile platform.The dynamic characteristics and amplitude-frequency response characteristics of the vibration isolation system are directly affected by the inertia product of the equipment,causing the coupling of the corresponding two angular vibrations.To quantify the influence of inertia products,the 6-DOF(degree of freedom)dynamic model of the system was established and simplified into a 2-DOF model according to the dynamic theory.Using the dimensionless method,the mathematical relationship between natural frequency and inertia product was deduced,and the amplitude-frequency response of the system with different inertia products was analyzed.Results show that the two natural frequencies of the system increase monotonically and decrease monotonically with the inertia product,respectively.The difference between the two natural frequencies of the system increases monotonically with the inertia product and has a minimum value when the inertia product is zero.The isolation performance of the inertial coupling system is better than that of the uncoupled system in the vibration-isolating zone in the low-order mode direction.