The Selection Method of Toeplitz Matrix Row Number Based on Covariance Driven Stochastic Subspace Identification
Stochastic Subspace Identification is a parameter identification method, which can effectively obtain modal parameters from the structural signal under ambient excitation. The choice of Toeplitz matrix row number directly influences the accuracy of identification. By constructing a correlation matrix, this paper derives the dimension of Toeplitz matrix influence the denoising ability ver SVD. The concept of condition number is introduced in solving the system matrix. according to the relationship between i and condition number of Toeplitz matrix, proving once again that i has influence on identification accuracy. Then researching the selection method of Toeplitz matrix row number i. Two simulations with two-degree spring vibration and a cropped delta wing model are used to research the method. The results show that after the determination of the suitable system order the smaller the Toeplitz matrix condition number is, the higher identification accuracy is.
1 Jiangsu Key Laboratory of Engineering Mechanics, Nanjing, 210096
2 Department of Engineering Mechanics, Southeast University, Nanjing, 210096
Abstract：Stochastic Subspace Identification is a parameter identification method, which can effectively obtain modal parameters from the structural signal under ambient excitation. The choice of Toeplitz matrix row number directly influences the accuracy of identification. By constructing a correlation matrix, this paper derives the dimension of Toeplitz matrix influence the denoising ability ver SVD. The concept of condition number is introduced in solving the system matrix. according to the relationship between i and condition number of Toeplitz matrix, proving once again that i has influence on identification accuracy. Then researching the selection method of Toeplitz matrix row number i. Two simulations with two-degree spring vibration and a cropped delta wing model are used to research the method. The results show that after the determination of the suitable system order the smaller the Toeplitz matrix condition number is, the higher identification accuracy is.
王燕1,2，杭晓晨1,2，姜东1,2，韩晓林1,2，费庆国1,2. 协方差驱动随机子空间的Toeplitz矩阵行数选择方法[J]. 振动与冲击, 2015, 34(7): 71-75.
Wang Yan1, 2, Hang Xiaochen1, 2, Jiang Dong1, 2, Han Xiaolin1, 2, Fei Qingguo1, 2. The Selection Method of Toeplitz Matrix Row Number Based on Covariance Driven Stochastic Subspace Identification. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(7): 71-75.
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