基于Daubechies小波基的木材声学振动信号分析与评价  

Analysis and evaluation of wood acoustic vibration signal based on Daubechies wavelet base

作　　者：尹玉雪 苗媛媛[1] 万珂 王秀雅 翟学勇 刘镇波[1] YIN Yuxue;MIAO Yuanyuan;WAN Ke;WANG Xiuya;ZHAI Xueyong;LIU Zhenbo(Key Laboratory of Bio-based Material Science and Technology(Northeast Forestry University),Ministry of Education,Harbin 150040,China)

机构地区：[1]生物质材料科学与技术教育部重点实验室(东北林业大学),哈尔滨150040

出　　处：《林业工程学报》2021年第5期68-75,共8页Journal of Forestry Engineering

基　　金：中央高校基本科研业务费专项资金(2572019BB05);国家自然科学基金(31670559)。

摘　　要：针对音板木材振动信号分析不深入的问题,本研究基于小波包分析方法对木材振动信号进行分析,建立一种木材声学振动评价的新方法。利用多通道FFT分析仪获取泡桐木材的振动信号,基于Daubechies小波基函数对振动信号进行3层小波包分解与重构,得到了振动信号的特征值,将小波包变换后木材振动信号的特征值与传统方法测定的声学振动性能参数进行比较分析。研究结果表明:木材的振动信号能量主要集中在0~1000 Hz,在传播的过程中能量衰减迅速;对振动信号进行时域分析时得出,木材的动态弹性模量随着峭度因子的增大而减小,随着峰值因子的增大而增大;基于Daubechies小波基的分析方法得到的振动信号特征值与声学振动参数之间具有显著的相关性,其中木材信号的特征能量率与木材声学振动参数动态弹性模量、声辐射品质常数以及声传播速度之间存在显著的正相关关系,与声阻抗以及对数衰减率的相关性及变化趋势之间有显著的负相关关系。研究表明,可以应用Daubechies小波对木材振动信号进行分析与评价,此方法为木材声学振动性能的客观评价提供了新思路。The previous studies on the analysis and processing of wood vibration signals were mostly limited to the fast Fourier transform,where advanced signal analysis methods were rarely used.Aiming at solving the problem that the soundboard wood vibration signal analysis is not in-depth and exploring the relationship between the characteristics of wood vibration signals and its acoustic vibration performance,a new method based on the wavelet packet analysis was established to analyze the wood vibration signals for wood acoustic vibration evaluation in this study.The vibration signal of Paulownia wood was obtained through the multi-channel fast Fourier transform analyzer.The signal was decomposed and reconstructed with a three-layer wavelet packet according to the Daubechies wavelet base,and the characteristic value of the vibration signal was attained.The characteristic value of the vibration signal after the wavelet packet transformation was compared and analyzed with the acoustic vibration performance parameters measured with traditional methods.The research results showed that the vibration signal energy of wood was mainly concentrated between 0-1000 Hz,and the energy decayed rapidly during the propagation process.When analyzing the vibration signal in the time domain,it was found that the dynamic elastic modulus of wood decreased with the increase of the kurtosis factor,and increased with the increase of the crest factor.Moreover,it was revealed that there was a significant correlation between the eigenvalues of the vibration signal and the acoustic vibration parameters based on the Daubechies wavelet basis analysis method.There was a significant positive correlation among the characteristic energy rate of wood signals,the dynamic elastic modulus of wood acoustic vibration parameters,and the sound radiation quality constant.Among them,there was a significant positive correlation between the characteristic energy rate of the wood signal and the dynamic elastic modulus of the wood acoustic vibration parameters,the sou

关 键 词：泡桐 音板木材 声学振动性能 DAUBECHIES小波 能量特征 振动信号 

分 类 号：S781.38[农业科学—木材科学与技术]