一类整星隔振器的等强度设计方法

Equal strength design method for a kind of whole-spacecraft isolator

航天发射振动环境幅值大、频带宽,并带有随机性,安全系数的提高对航天发射的高可靠性要求意义重大,尤其对于整星隔振器。针对一类整星隔振器,首次引入等强度梁理论建立了相应的设计方法。首先,在总结分析了国内外相关典型整星隔振器结构特点的基础上,建立了对应于这类隔振器的超静定组合梁模型。然后,基于小变形假设、莫尔定理及等强度梁理论,建立了联系隔振器结构参数与性能参数的等强度力学模型,并推导了迭代设计方法。等强度设计方法能够由结构参数直接预测性能参数,并且可按需要的安全系数设计具有等强度特性的整星隔振器。最后,设计了示例非等强度与等强度隔振器,分析表明所提方法可使隔振器支架应力分布均匀性显著改善,安全系数明显提高。

Because of high vibration amplitude, large frequency oanflwm^n, anti vllJratlUil Wltil IaLLUULLILL~ L^A LL＊C IL~~VLAaLI^Va. environment of space launch, the improvement of safe factor is of high significance for the special high reliability requirement of space launch, especially for that of the whole-spacecraft isolator. In this paper, the equal strength beam theory is first in- troduced and the corresponding mechanical model is established for the whole-spacecraft isolator. First, in summing up the domestic and foreign whole-spacecraft isolators＇ structural characteristics, we established a statically indeterminate composite beam model. Then, based on the small deformation assumption, Mohr theorem and equal strength beam theory, the mechan- ical model between the isolator＇s structural parameters and performance parameters is developed. The design method based on equal strength is derived after the explicit non-uniform strength mechanical model has been given. The proposed method can directly computes the isolator＇s performance parameters by structural parameters, and can design the equal strength isolator with needed safe factor. Finally, two kinds of isolators have been designed and analyzed. The results show that the stress dis- tributes much more uniformly in the isolator＇s bracket and the safe factor can be improved significantly.