Research On Array Imaging And Defect Detection Based On Underwater Active Electric Field

The underwater detection method of active electric field comes from weak electric fish,which is a new underwater detection technology,Researchers hope to make some complementary means to the current underwater detection methods.Based on the principle of underwater active electric field detection,this paper mainly studies the imaging and defect detection of underwater objects,On the one hand,starting from active electric field imaging,the array and the corresponding imaging algorithm are designed to observe the imaging effect through experiments;On the other hand,starting from the transition frequency of the target object,the transition frequency is applied to the underwater defect detection,and we analyze the relationship between transition frequency and defect.In summary,the content of this paper is divided into the following points:1.We have studied several mainstream underwater detection methods,this paper analyzes the advantages and disadvantages of current traditional detection methods,and puts forward the advantages of active electric field underwater detection.Based on the principle of active electric field detection,firstly,the electric field model is built to simulate the launch and reception of weak current fish,and then the active electric field underwater experiment platform is built in the experiment.2.From the perspective of active electric field imaging,we explore the algorithm suitable for underwater active electric field imaging.On the built experimental platform,by comparing different electrode materials,we select the electrode suitable for underwater detection,and build an array to receive the imaging.In order to analyze the imaging effect,the verification experiments are carried out by using various shapes of target objects,such as cube,cuboid,triangular prism,cylinder,cross,I-shape,parallelogram,trapezoid and so on.3.we have explored the influence of transition frequency on the detection of object defects,Based on the analysis method of short-time Fourier transform,a threedimensional joint time-frequency spectrum of time frequency amplitude is established,a defect detection algorithm is designed to detect defects in the experiment,and a transition frequency recognition algorithm is designed to judge the transition frequency of different objects in the experiment.4.Based on the above algorithm theory,we integrate these functions through LabVIEW,and design a variety of defects.The relationship between the transition frequency and the defect is found by experiments on metal objects and underwater pipelines made of copper,aluminum,iron and steel.Then it extended to nonmetal,and tested the non-metal defects,and obtained some defects information.5.We summarize the full text and analyze the potential applications of imaging and defect detection.