基于ZYNQ加速的激光超声全聚焦成像技术研究  

Research on Laser Ultrasonic Total Focusing Imaging Method Based on ZYNQ Acceleration

作　　者：吴婵娟 应恺宁 戴鹭楠 谭钧夫 沈中华[2] 倪辰荫[1] Wu Chanjuan;Ying Kaining;Dai Lunan;Tan Junfu;Shen Zhonghua;Ni Chenyin(School of Electronic Engineering and Optoelectronic Technology,Nanjing University of Science and Technology,Nanjing 210094,Jiangsu,China;College of Science,Nanjing University of Science and Technology,Nanjing 210094,Jiangsu,China;College of Computer Science and Engineering,Nanjing University of Science and Technology,Nanjing 210094,Jiangsu,China)

机构地区：[1]南京理工大学电子工程与光电技术学院,江苏南京210094 [2]南京理工大学理学院,江苏南京210094 [3]南京理工大学计算机科学与工程学院,江苏南京210094

出　　处：《中国激光》2023年第18期250-260,共11页Chinese Journal of Lasers

基　　金：江苏省研究生科研与实践创新计划项目(KYCX22_0420)。

摘　　要：全聚焦方法(TFM)具有成像分辨率高、缺陷表征能力强的优点,但其存在数据需求量大、计算复杂、耗时过长等问题。针对上述问题,并结合激光超声检测技术,进行了基于ZYNQ平台加速的激光超声全聚焦技术研究。首先建立了基于激光超声的全聚焦算法,并引入激光超声方向性系数进行优化;进一步,搭建了激光超声扫描检测装置进行实验验证,使用线激光源激发超声信号,利用多普勒测振仪探测回波信号;然后使用形成的激光超声全聚焦成像算法进行内部缺陷的检测和定位,并与合成孔径聚焦算法获得的结果进行比较,从而验证了算法的正确性和可行性;最后将形成的激光超声全聚焦成像算法移植到ZYNQ平台上,对激光超声全聚焦成像算法进行了并行优化及双核设计,实现了算法加速。研究结果表明:激光超声全聚焦技术相比于合成孔径聚焦技术,成像信噪比更高、定位更准确;基于ZYNQ加速的激光超声全聚焦成像算法不会降低成像质量,且耗时相比于计算机缩短了86%。Objective With the continuous emergence of various materials and the improvement of the quality requirements of modern industry for mechanical parts,non-destructive testing technology has been rapidly developed.Ultrasonic non-destructive testing has been widely used because of its high sensitivity,penetrability and other advantages;it has become an indispensable tool in aerospace,railway,oil pipeline,and other industrial testing.As a hot spot in the field of industrial non-destructive testing in recent years,phased array testing technology exhibits the characteristic of flexibility in focusing.However,all ultrasonic sub beams are focused at a constant depth,and reflectors outside the focus area cannot be detected sensitively.Synthetic aperture focusing technology(SAFT)can synthesize multiple small numerical aperture transducers into large numerical aperture transducers,which can obtain higher resolution reconstructed images and provide a more reliable basis for the qualitative analysis of defects.The total focusing method(TFM)is developed by combining phased array detection technology and synthetic aperture focusing technology.The total focusing method uses all the transceiver combinations in the phased array elements to detect defects and performs image post-processing on the obtained full matrix data.It uses all the information of the data to recover the detection signal to the maximum extent,and obtains imaging results with a stronger defect characterization ability and higher resolution.However,it has many limitations such as a large data demand,complex calculations,and the need for a substantial amount of time.To address these issues,the laser ultrasonic total focusing imaging method based on ZYNQ acceleration is studied in conjunction with laser ultrasonic testing technology.Methods First,the total focusing imaging method based on laser ultrasound is established,and the laser ultrasound directivity coefficient is then introduced to optimize the algorithm by analyzing the imaging principle.Furthermore,a lase

关 键 词：测量 激光超声 全聚焦成像算法 ZYNQ平台 无损检测 

分 类 号：TG115.28[金属学及工艺—物理冶金]