基于概率成像的二维波束聚焦冲击定位方法研究

Research on Two⁃Dimensional Beam Focusing Impact Location Based on Probability Tomography

冲击损伤监测是结构健康监测的主要研究内容之一.本文提出了一种基于十字型传感器布置方法的二维波束聚焦概率成像定位算法,采用十字阵列型的传感器布置方法减小了系统盲区,通过二维波束聚焦概率成像方法提高了冲击定位的精度.在二维波束聚焦算法中,波速的准确性是影响结构冲击损伤定位的主要因素,本文通过统计分析得到波速的概率分布函数,带入二维波束聚焦概率成像定位算法中对冲击损伤进行监测,分别得到横向阵列与纵向阵列的概率分布图,对两者进行融合成像可以得到更为精确、科学且直观的冲击损伤定位结果.通过实验研究验证了该方法的有效性与实用性.

Impact is one of the main damage types involved in structural health monitoring research.To improve the impact localization accuracy,a two⁃dimensional beam⁃focusing probabilistic imaging localization algorithm based on the cross⁃shape sensor arrangement is proposed.The blind zone of impact detection can be reduced through the cross⁃shape sen⁃sor arrangement.And the accuracy of impact localization can also be improved by two⁃dimensional beam⁃focusing probabi⁃listic imaging method.In the two⁃dimensional beam focusing algorithm,the accuracy of the impact wave speed testing has high influence on the effect of the impact localization.The probability distribution of the wave velocity is obtained through statistical analysis.The distribution is brought into the two⁃dimensional beam focusing probabilistic imaging localization al⁃gorithm to localize the impact.The probability distribution image of the horizontal sensor array and the vertical sensor array are obtained separately and further fused into one more accurate,scientific and intuitive probability distribution image.The validity and practicability of the method are verified through experimental research.