基于矩阵映射理论,本文提出了一种ERA的改进算法--C/ERA。该算法在传统的ERA方法奇异值截断过程之后重建Hankel矩阵,继而将矩阵各元素由其所在反对角线上的元素数学平均值代替并引入Frobenius第二范数准则控制迭代次数。五自由度阻尼弹簧质量系统仿真以及海洋平台缩尺模型物理模型的试验结果表明: C/ERA方法能更强的消噪能力,对高阶模态更敏感而且在低阶模态阻尼的识别上有更高的识别精度。
Abstract
Based on matrix mapping theory, An improved eigensystem realization algorithm(ERA), called C/ERA , is proposed in the paper. It rebuilds a Hankel matrix by replacing all elements of each anti-subdiagonal by the arithmetic average of the elements along the anti-subdiagonal and introduces the concept of using the Frobenius norm (L2-norm) to control iterations number after implementing SVD algorithm by ERA method. With the data associated with a 5-DOF mass-spring-dashpot system and jacket-type platform under impact loading, it is proved that C/ERA has a better capacity of de-noising, higher accuracy for low order modes and identifies more high order modes than ERA does.
关键词
模态参数识别 /
C/ERA /
消噪
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Key words
Model parameter identification /
C/ERA /
De-noising.
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参考文献
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脚注
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