Detection method for hole positions in logs based on impact echo
LIANG Chen1，FENG Hailin2，FANG Yiming2，LI Jian2
1.School of Information Engineering, Zhejiang A & F University, Hangzhou 311300, China；
2. Zhejiang Provincial Key Lab of Intelligent Monitoring in Forestry and Information Technology, Hangzhou 311300, China
In order to quickly detect internal hole positions along the axial direction of a log, an impact echo method based on a log’s stress wave signal decomposition was proposed. Firstly, the collected stress wave signals in a log were decomposed with the ensemble empirical mode decomposition (EEMD) method. Then the intrinsic mode functions (IMFs) being sensitive to internal holes in a log were found based on their time domain characteristics combined with IMF components’ correlation coefficients. Finally, Fourier transformation was done for the found IMFs. According their frequency domain features, the positioning for log’s internal hole defect locations was realized. The test results showed that the proposed method is effective.
梁臣1，冯海林2，方益明2，李剑2. 基于冲击回波的原木内部空洞位置检测方法研究[J]. 振动与冲击, 2018, 37(11): 265-272.
LIANG Chen1，FENG Hailin2，FANG Yiming2，LI Jian2. Detection method for hole positions in logs based on impact echo. JOURNAL OF VIBRATION AND SHOCK, 2018, 37(11): 265-272.
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