低成本非接触式红外无损检测技术研究

发布时间：2018-01-29 21:58

本文关键词： 红外无损检测红外热电堆传感器非均匀校准 FPGA Labview　出处：《南京理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：红外无损检测技术是无损检测领域的研究热点之一,具有快速、非接触、准确和直观等独特优势,具有广阔的发展前景。本文以红外热电堆传感器为基础,研制出一套能检测多种复合材料内部缺陷的红外无损检测系统,系统不仅可检测出具有较大深宽比内部缺陷,同时兼顾红外无损检测分析功能,具有低成本、适用范围广、灵活性高的特点,可满足工业材料的实时检测需求。本文首先根据系统的设计要求,开展了系统的整体设计,分析了电阻和运放等器件的噪声特性,并根据红外热电堆传感器的性能参数设计了低噪声信号放大电路和低通有源滤波电路。其次,根据系统功能需求设计了无线通信模块来加密传输实验数据,使数据采集电路和数据收发电路硬件分离,增大了系统的灵活性。并设计了多通道高速采样模/数转换电路、低纹波系数电源电路、上位机Labview数据显示界面和基于FPGA的主控制器模块,编写了数据采集控制程序。第三,针对线阵红外热电堆传感器存在的非均匀性问题提出了一种改进的传感器非均匀性校准算法,该算法在传统二点校准算法的基础上,可实现在较宽温度范围校准,运用此算法取得了良好的校准效果。最后,利用大功率加热烤灯对碳碳材料、碳纤维复合材料和玻璃纤维复合材料三种不同热扩散系数复合材料内部缺陷做了红外无损检测实验,通过分析实验结果,得出设计的系统噪声指标为0.067mV,系统信噪比为89dB,可检测的内部缺陷深宽比约为:碳碳材料0.4,碳纤维复合材料0.5,玻璃纤维复合材料0.8,表明该系统具有低成本、灵活性高、适用范围广并可检测出材料内部较大深宽比缺陷的特点。
[Abstract]:Infrared nondestructive testing technology is one of the hot research field of nondestructive testing is fast, non-contact, accurate and intuitive and other advantages, has broad prospects for development. Based on the infrared thermopile sensor based on infrared detection can develop a variety of composite materials internal defect nondestructive testing system, the system can not only detect with the large aspect ratio of internal defects, taking into account the infrared NDT analysis function, has the advantages of low cost, wide application range, high flexibility, can meet the requirements of real-time detection of industrial materials. Firstly, according to the design requirements of the system, carry out the overall design of the system, analyzes the characteristics of noise resistance and operational amplifier devices. According to the performance parameters of infrared thermopile sensor design low noise signal amplifying circuit and low pass active filter circuit. Secondly, according to the function of the system was designed The wireless communication module to encrypt data, the data acquisition circuit and data transceiver circuit hardware separation, increase the flexibility of the system. And the design of multi channel high speed sampling analog-to-digital conversion circuit, low ripple power supply circuit module, main controller and PC Labview data display interface based on FPGA, the preparation of data acquisition control procedures. Third, based on the linear array infrared thermopile sensor has the nonuniformity problem and proposes an improved algorithm for non uniformity calibration of sensor, based on the traditional two point calibration algorithm, can be realized in a wide temperature range calibration, using this algorithm achieved good calibration results. Finally, roast lamp on carbon carbon material with high power heating, carbon fiber composite material and glass fiber composite materials with three different thermal diffusion coefficient of the composite made of internal defects of infrared nondestructive testing experiment And through the analysis of experimental results, the system noise index design for the 0.067mV system, the signal-to-noise ratio is 89dB, the internal defect detection depth to width ratio is about 0.4: carbon carbon material, carbon fiber composite materials 0.5, glass fiber composite materials 0.8, show that the system has low cost, high flexibility, wide application range and can detect the defects inside the material large aspect ratio features.

【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB302.5

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