学科分类
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12 个结果
  • 简介:VisualimagesensorisdevelopedtodetecttheweldpoolimagesinpulsedMIGwelding.Anexposurecontroller,whichiscomposedofthemodulesofthevoltagetransforming,theexposureparameterspresetting,thecomplexprogrammablelogicdevice(CPLD)basedlogiccontrolling,exposuresignalprocessing,thearcstatedetecting,themechanicalirisdrivingandsoon,isdesignedatfirst.Then,avisualimagesensorconsistsofanordinaryCCDcamera,opticalsystemandexposurecontrollerisestablished.Theexposuresynchroniccontrollogicisdescribedwithvery-high-speedintegratedcircuithardwaredescriptionlanguage(VHDL)andprogrammedwithCPLD,todetectweldpoolimagesatthestageofbasecurrentinpulsedMIGwelding.Finally,bothbeadonplateweldingandVgroovefilledweldingarecarriedout,clearandconsistentweldpoolimagesareacquired.

  • 标签: 焊接池 图象传感器 脉冲 可控制曝光
  • 简介:Inthispaper,theX-raynondestructivetestmethodofsmalldefectsinprecisionweldmentswithcomplexstructurewaspresented.Toresolvethedifficultyofdefectsegmentationinvariablegreyimage,theimageprocessingbasedonVisualBasicprogrammingmethodwasadopted.ThemethodsofautomaticcontrastandpartialgreystretchwereusedtoenhancetheX-raydetectionimagewhichhasrelativelylowcontrast,thenautomaticthresholdmethodwascarriedouttosegmentthetwohighintensityzones,andweldzoneswhichcontainthesmalldefectswasextracted.Smoothingandsharpenprocessingwereproceededontheextractedweldzones,andsmalldefectsinX-raydetectionimageofweldmentswithcomplexstructureweresegmentedbyusingthemethodofbackgroundsubtractionintheend.Theeffectsofrasterwereeliminated,andbecauseofthattheimageprocessingwasonlyproceededontheextractedweldzones,thecalculatedspeedusingtheaboveprovidedalgorithmwasimproved.

  • 标签: 精密焊接件 复杂结构 微小缺陷检测 图象分割
  • 简介:Imagesensorhasbeenoneofthekeytechnologiesinintellectualizedroboticswelding.Edgedetectionplaysanimportantrolewhenthevisiontechnologyisappliedinintellectualizedweldingroboticstechnologies.Thereareallkindsofnoisesinweldingenvironment.Thealgorithmsincommonusecannotbeappliedtotherecognitionofweldingenvironmentdirectly.Theedgeofimagescanbefellintofourtypes.Theweldimagesareclassifiedbythecharacteristicofweldingenvironmentinthispaper.Thispaperanalyzessomealgorithmsofedgedetectionaccordingtothecharacterofweldingimage,somerelativeadvantagesanddisadvantagesarepointedoutwhenthesealgorithmsareusedinthisfield,andsomesuggestionsaregiven.Thefeatureextractionofweldseamandweldpoolaretwotypicalproblemsintherealizationofintellectualizedwelding.Theiredgefeaturesareextractedandtheresultsshowtheapplicabilityofdifferentedgedetectors.Thetradeoffbetweenprecisionandcalculatedtimeisalsoconsideredfordifferentapplication.

  • 标签: 电弧焊 焊接图像 边界检测 焊接裂痕 焊接池
  • 简介:Computervisionhascomeintousedinthefieldsofweldingprocesscontrolandautomation.Inordertoimproveprecisionandrapidityofweldingimageprocessing,anovelmethodbasedonfractaltheoryhasbeenputforwardinthispaper.Comparedwithtraditionalmethods,theimageispreliminarilyprocessedinthemacroscopicregionsthenthoroughlyanalyzedinthemicroscopicregionsinthenewmethod.Withwhich,animageisdivideduptosomeregionsaccordingtothedifferentfractalcharactersofimageedge,andthefuzzyregionsincludingimageedgesaredetectedout,thenimageedgesareidentifiedwithSobeloperatorandcurvedbyLSM(LeaseSquareMethod).Sincethedatatobeprocessedhavebeendecreasedandthenoiseofimagehasbeenreduced,ithasbeentestifiedthroughexperimentsthatedgesofweldseamorweldpoolcouldberecognizedcorrectlyandquickly.

  • 标签: 不规则碎片理论 焊接 图象处理 边缘探测
  • 简介:Adual-beamelectronicspecklepatterninterferometry(ESPI)systemwasadoptedtogetspecklepatternsforthemeasurementofweldingdynamicdisplacementfields.Themathematicalmodelofthissystemwasdescribed,basedonwhichmethodsoftheESPIpatternimageprocessingwerediscussed.Graytransformationandhistogramequalizationwereusedtoenhancethecontrastofspecklepatterns.Adiscretecosineimageprocessingmethodwascarriedoutandanexponentlow-passfilterwaschosentoreducemultiplicativenoiseinspecklepatterns.Specklegrainnoisecanbeeliminatedeffectivelyaftertheseprocesses.

  • 标签: 焊接 电子光斑干涉测量 图形处理 离散余弦指数滤波器
  • 简介:ThelateralwaveinultrasonicTOFD(timeofflightdiffraction)imagehasatailintransittime,whichdisturbsthedetectionandevaluationofshallowwelddefect.Meanwhile,thelateralwaveandback-wallechothatactasbackgroundaddredundantdataindigitalimageprocessing.Inordertoseparatedefectwavefromlateralwaveandpreparethewayforfollowingimageprocessing,analgorithmofbackgroundremovalmethodnamedasmean-subtractionisdeveloped.Basedonthis,animprovedmethodbystatisticoftheenergydistributionintheimageisproposed.Theresultsshowthatbychoosingproperthresholdvalueaccordingtotheaxialenergydistributionoftheimage,thebackgroundcanberemovedautomaticallyandthedefectsectionbecomespredominant.Meanwhile,diffractivewaveofshallowwelddefectcanbeseparatedfromlateralwaveeffectively.

  • 标签: 超声检验 TOFD 飞行衍射时间 数字图象处理 背景消除 焊接
  • 简介:Obtainingtheimageofmoltenpoolaluminumalloy'stungsteninertgas(TIG)weldingbecomesachallengingproblemintheweldingfield.Inthispaper,abran-newopticalsensorbasedanalyzingthelightspectrumwasdesigned,andtheclearimageofthemoltenpoolduringthealuminumalloy'sweldingusingthecommonindustrialCCDcamerawasobtained.Andwiththenewalgorithmprovidedbymyself,thedesirablecharacteristicparametersofthemoltenpoolofaluminumalloy'sweldingwereobtained,anditprovidesagoodbaseforadvancedmonitorweldingquality.

  • 标签: 铝合金 TIG焊接 金相光谱 图形遥感
  • 简介:AnexperimentalsetupofacquiringthecoaxialvisualimageofthemoltenpoolandkeyholeinhighpowerNd:YAGlaserweldingisintroducedinthispaper.Itisoneofthemostdifficultproblemsinacquiringcoaxialimagethatthecoaxialimagingsignalofmoltenpoolandkeyholemustbeseparatedfromthelaserbeamwithhighpower.Thisproblemwasresolvedbydesigningadichroiticspectroscope.Thecharacteristicsofimagingsignalwereanalyzedandthecoaxialimageofmoltenpoolandkeyholewasacquired.Asmoothingfilterandahomomorphicfilterweredesignedtoremovethelowfrequencynoiseandtoenhancetheimageaccordingtothecharacteristicsofimagingsignal.Atlast,edgesofmoltenpoolandkeyholeweredetectedandextractedbasedonimagesegmentationwiththreshold.

  • 标签: ND:YAG激光 激光焊接 高功率激光 熔池 小孔 图象处理