测量信息对飞行器工作模态辨识精度影响分析

The Influence of the Measure Information on the Operational Mode Identification of the Aircraft

针对模态辨识结果对输入的敏感性,研究了测量信息对飞行器工作模态辨识精度的影响。介绍了自回归-滑动平均(auto-regressive and moving average,简称ARMA)模型环境激励模态辨识方法的理论、试验测点和激励情况,并给出了试验研究方案情况。通过选择不同测点布置组合,研究了测点布置对辨识结果的影响。对各测点数据人为增加噪声,研究了数据品质对辨识结果的影响。研究发现,测点数目较多,且测点布置在振型数值较大位置,辨识结果较好。

Whereas the mode result is sensitive to the input signal,the influence of the measure information on the operational mode identification of the aircraft is investigated.The theory of the auto-regressive and moving average(ARMA)-natural excitation technique(NExT)method is introduced,and the strategy of experiment is put forward,which includes the measuring points distributing and the excitation method.Several measuring points distributing cases are put forward,where the influence of the measure information on the operational mode identification is studied,and the influence of the data accuracy on the operational mode identification is investigated.It is found that the mode identification result is better when the measuring points is abundant and locate at the bigger value of the modal shapes.