基于Laplace小波相关滤波的结构模态参数精确识别方法

HIGH PRECISION MODAL PARAMETER IDENTIFICATION BASED ON LAPLACE WAVELET CORRELATION FILTERING

为了从结构脉冲响应信号中精确识别结构模态参数,提出一种基于Laplace小波相关滤波的结构模态参数精确识别方法。首先对结构的脉冲响应信号进行经验模式分解,将结构多阶模态响应信号分解为与各单阶模态响应信号一一对应的分量,再对这些分量分别进行Laplace小波相关滤波便可准确识别结构的各阶模态参数。仿真信号的计算结果表明该方法可以得到精确的阻尼固有频率,并能准确地锁定阻尼比。悬臂梁力锤激励试验结果表明该方法在实际结构的模态参数识别中也非常有效。

Focused on the modal parameter identification from impulse response signals, a novel method of modal parameters identification based on Laplace wavelet correlation filtering is proposed. Using EMD method, the response signals of structure are firstly decomposed into several uncoupled signals, vibrating at a natural frequency. Secondly, the Laplace wavelet correlation filtering method is employed to identify modal parameters from each uncoupled signal. The computing results of simulative signals show that the proposed method can not only identify accurate damped natural frequency parameters, but also identify the damping ratio with high precision. The analyzing results of experiment signals show that the proposed method is also effective in practical application.