摘要
准确把握航天器振动试验条件是实现航天器有效检验的前提。首先,通过典型柔性结构试验表明振动台刚性边界不同于真实环境的柔性边界条件,导致结构传递函数发生改变,说明如果以传统的有效载荷界面加速度包络作为试验条件可能导致过试验或欠实验;然后,采用载荷映射方法,以响应等效为目标,基于有限元模型,根据实际响应与试验边界,采用数值优化方法计算试验边界条件下的映射载荷;最后,以此来制定振动试验条件。结果表明,载荷映射方法可以有效解决边界条件不同可能引起的欠试验问题,同时结合主动下凹方法或力限技术可以缓解有效载荷共振频率处的过试验现象。
The determination of vibration tests specifications is a prerequisite for rightly examination of the capability of spacecraft structure.The rigid boundary condition in the experiments is sometimes significantly different from that of the real mounting structure,resulting in the discrepancy of transfer function.Taking the envelope of interface acceleration as the specification would cause over-testing or under-testing condition.Load mapping method(LMM),which aims at the response equivalence,takes the real response and experiment boundary condition as the input and uses optimization algorithm to calculate the mapping load based on FEM model.It is found that LMM can solve the under-testing caused by boundary condition difference from the analysis and test results of a representative structure that has a flexible boundary condition.The over-testing at resonance frequencies of the payload can be reduced by notching method or Force Limit Method.
出处
《振动．测试与诊断》
EI
CSCD
北大核心
2017年第5期934-940,共7页
Journal of Vibration,Measurement & Diagnosis
关键词
振动环境试验
航天器
响应等效
载荷映射
vibration environment test
spacecraft
response equivalence
load mapping
