基于红外脉冲相位热成像技术的玻璃钢深度测量

FRP depth measurement based on pulsed phase thermography

为探索红外热成像技术用于玻璃钢材料厚度测量的方法,文中使用闪光灯脉冲激励热成像的方法对玻璃钢平底洞标准件进行检测,通过脉冲相位法(PPT)进行数据处理,提取频域信息、消除噪声,并在试验设备采样频率不能满足盲频测量要求的限制条件下,建立相位阈值,完成了厚度测量。试验结果表明,玻璃钢试件的物理特性会对测量结果造成误差,但经数值优化后可在一定厚度范围内得到和实际深度接近的探测值,该方法可以作为玻璃钢厚度测量的有效手段。

Aiming at developing a method for depth measurement in fiber reinforced plastic （FRP） by thermography, flash pulse excitation was applied to test an FRP specimen with plate-bottom holes. The data was processed to accomplish depth measurement using pulsed phase thermography （PPT） method including extracting frequency curve and removing the impact of noise. A minimum phase threshold was also established when the sampling frequency could not meet the demand of measuring blind frequency. Experiment results show that physical characteristics of FRP can affect the measurement accuracy. But through the optimization algorithm, the depth which is close to the actual value of the detection can be obtained. Within a certain range of thickness, PPT method can still be an effective method for FPR depths measurement.