摘要
大型船体结构振动测试的关键问题是传感器数量很多,过多的传感器花费太高但减少传感器数量又可能导致误差明显增大。本文基于结构模态矩阵条件数优选传感器布置位置和数量,并重构整个结构振动,在迭代过程的每个循环中消去对模态矩阵条件数贡献最大的传感器位置。文中分析了每次迭代消除位置数量的影响并做了仿真验证。实验验证了本文方法的准确性,某实验结构26个优化的传感器布置与200个初始传感器布置对比其重构误差仅为2.4d B,另一实验结构27个优化的传感器布置与264个初始传感器布置对比其重构误差仅为3.0d B。本方法或可用于大型结构物的振动测量与实验。
The critical issue of vibration test on hull structures with large size is the numerous amounts of sensors. Too many sensors lead to excessive consumption whereas notable error would come from reducing the number of sensors. An approach is proposed to reconstruct the complete structural vibration, which choose the locations and number of sensors optimally based on the condition number of structural modal matrix. This iterative progress eliminates the sensor location that contributes the most significantly to the condition number of modal matrix in each cycle. The influence of the location number eliminated in each cycle is analysed and emulated in this paper. An experiment validates the precise of this approach. Vibration responses reconstructed from the data of 26 optimal sensors are consistent with the responses measured by 200 initial sensors, the vibration error is only 2.4 d B for one test structure. For another structure, the error is 3.0 d B between the reconstructed data from 27 optimal sensors and the responses measured by 264 initial sensors. This approach may be applied to vibration test and measurement on large structures.
引文
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