基于压缩感知的复合材料板Lamb波场重构及损伤成像

为了解决全波场数据获取耗时的问题，引入压缩感知算法对波场进行稀疏表示。然而受限于导波在复合材料中复杂的传播特性，压缩感知在复合材料板中的应用成为难题。为此通过考虑导波在复合材料板中传播的各向异性波数特性，构建计算频带内不同角度下的波数库用于波场重构。同时在损伤分析阶段，提出了一种无需基准信号的复合材料损伤散射波场分离技术，精准实现入射波场的去除，提升损伤定位的精度。单损伤的实验和仿真结果表明，所提方法能够在低于90%的奈奎斯特采样点情况下实现波场的重构，且损伤定位误差均小于最小波长的2/3。双损伤的实验结果表明，所提方法可有效定位双损伤，相关成果可为复合材料损伤检测的实际运用提供理论和方法基础。 

Lamb wavefield reconstruction and damage imaging of composite plate based on compressed sensing

In order to solve the time-consuming problem of data acquisition of the whole wavefield, a compressed sensing algorithm was introduced to represent the wavefield sparsely. Due to the complex propagation characteristics of guided waves in composite materials, the application of compressed sensing in composite plates becomes difficult. Hence, by considering the anisotropic wavenumber characteristics of the guided waves propagating in the composite plate, a wavenumber library under different angles in the calculated frequency band was constructed for wavefield reconstruction. In the stage of damage analysis, a composite material damage scattering wavefield separation technology without reference signal technology was proposed to accurately remove the incident wavefield and improve the accuracy of damage location. Simulation and experimental results show that the proposed approach allows a reduction of the measurement locations required for accurate signal recovery to less than 90% of the original sampling grid and the single damage location error is less than 2/3 of the minimum wavelength. In addition, the double-damage experimental results show that the proposed method can effectively locate the double-damage, and related results can provide a theoretical and methodological basis for the practical application of composite damage detection.