State Key Laboratory of Precision Measurement Technology and Instrument, Tianjin University, Tianjin 300072, China.
Beijing Institute of Spacecraft Environment Engineering, Beijing 100094, China.
Sensors (Basel). 2023 Mar 12;23(6):3052. doi: 10.3390/s23063052.
Composite materials are widely used, but they are often subjected to impacts from foreign objects, causing structural damage. To ensure the safety of use, it is necessary to locate the impact point. This paper investigates impact sensing and localization technology for composite plates and proposes a method of acoustic source localization for CFRP composite plates based on wave velocity-direction function fitting. This method divides the grid of composite plates, constructs the theoretical time difference matrix of the grid points, and compares it with the actual time difference to form an error matching matrix to localize the impact source. In this paper, finite element simulation combined with a lead-break experiment is used to explore the wave velocity-angle function relationship of Lamb waves in composite materials. The simulation experiment is used to verify the feasibility of the localization method, and the lead-break experimental system is built to locate the actual impact source. The results show that the acoustic emission time-difference approximation method can effectively solve the problem of impact source localization in composite structures, and the average localization error is 1.44 cm and the maximum localization error is 3.35 cm in 49 experimental points with good stability and accuracy.
复合材料应用广泛，但常受到外物冲击，造成结构损伤。为确保使用安全，需要定位冲击点。本文研究了复合材料板的冲击传感和定位技术，提出了一种基于波速-方向函数拟合的 CFRP 复合材料板声源定位方法。该方法对复合材料板进行网格划分，构建网格点的理论时差矩阵，并与实际时差进行比较，形成误差匹配矩阵，从而实现对冲击源的定位。本文采用有限元仿真结合铅折断实验，探讨了复合材料中兰姆波的波速-角度函数关系。仿真实验验证了定位方法的可行性，并建立了铅折断实验系统以定位实际冲击源。结果表明，声发射时差近似法能够有效解决复合材料结构中的冲击源定位问题，在 49 个实验点的平均定位误差为 1.44cm，最大定位误差为 3.35cm，具有较好的稳定性和准确性。
