某宇航相控阵天线振动故障分析

文中针对某宇航相控阵天线在随机振动验收试验过程中的振动故障，首先通过罗列故障树和摸底试验进行故障定位，分析认为DSP芯片引脚在振动过程中应力过大是造成其开裂的主要原因；然后通过有限元法计算试验条件下DSP芯片引脚处的加速度和应力响应，仿真结果与试验结果比较一致；最后根据有限元模型开展相控阵天线主结构的优化设计，增加主结构的刚度，优化DSP芯片布局，在波控模块与主结构之间采用橡胶减振器减振。仿真结果显示优化后的DSP芯片动力学响应得到了极大改善，并通过了振动试验验证。这为髙量级随机振动减振设计提供了理论和试验依据。

Vibration Fault Analysis of an Aerospace Phased Array Antenna

The malfunction and failure of an aerospace phased array antenna during the random vibration test are studied in this paper. First, the root causes are identified by fault tree and assessment experiments. It is found that the main cause of the DSP chip crack is stress concentration on pins during vibration. Then, the acceleration and stress responses of DSP chips under the test conditions are calculated by finite element simulation. The simulation results are well consistent with the experimental results. Finally, the main structure of phased array antenna is optimized based on the finite element model by increasing the stiffness of the main structure, optimizing the DSP chip layout and adding the rubber absorber between the wave controller module and the main structure. The simulation results show that the dynamic response of the DSP is greatly improved after optimization, which is verified by vibration test. This study provides theoretical and experimental basis for the vibration damping design of high order random vibration.