简介:Resortingtocubicsplinefunctioninsteadofparametricsplinerepresentation,anexplicitfairnessindicatorandanefficientfairingalgorithmfor2Dcurvesarepresented.Theinputpointsequenceisfirstlypartitionedintoseveraloverlappedfunctionsegments.Foreachsegment,acubicsplinefunctionisusedastherepresentationtoolwhichentailsapolylineapproximationofcurvatureplot.Basedontheextrinsicrelationshipbetweenthepolylineandthepositionsofdatapoints,acoarse-to-finefaringmethodisproposedwhichefficientlyidentifiesandeliminatestheunnecessaryinflectionpoints.Ouralgorithmgeneratesthebestresultstodate,whichisvalidatedbynumerouspracticalexamples.
简介:Thetraditionalstrategyof3Dmodelreconstructionmainlyconcentratesonorthographicprojectionsorengineeringdrawings.Buttherearesomeshortcomings.Suchas,onlyfewkindsofsolidscanbereconstructed,thehighcomplexityoftimeandlessinformationaboutthe3Dmodel.Theresearchisextendedandprocesscardistreatedaspartofthe3Dreconstruction.Asetofprocessdataisasupersetof2Dengineeringdrawingsset.Thesetcomprisesprocessdrawingsandprocesssteps,andshowsasequencingandasymptoticcoursethatapartismadefromroughcastblanktofinalproduct.Accordingtothesecharacteristics,theobjecttobereconstructedistranslatedfromthecomplicatedengineeringdrawingsintoaseriesofmuchsimplerprocessdrawings.Withtheplentifulprocessinformationaddedforreconstruction,thedisturbancessuchasirrelevantgraph,symbolandlabel,etc.canbeavoided.Andmore,theformchangeofbothneighborprocessdrawingsissolittlethattheengineeringdrawingsinterpretationhasnodifficulty;inaddition,theabnormalsolutionandmulti-solutioncanbeavoidedduringreconstruction,andtheproblemsofbeingapplicabletomoreobjectsissolvedultimately.Therefore,theutilitymethodfor3Dreconstructionmodelwillbepossible.Ontheotherhand,thefeatureinformationinprocesscardsisprovidedforreconstructionmodel.Focusingonprocesscards,thefeasibilityandrequirementsofWorkingProcedureModelreconstructionisanalyzed,andthemethodtoapplyandimplementtheNaturalLanguageUnderstandingintothe3Dreconstructionisstudied.Themethodofasymptoticapproximationproductwasproposed,bywhicha3Dprocessmodelcanbeconstructedautomaticallyandintelligently.Theprocessmodelnotonlyincludestheinformationaboutpartscharacters,butalsocandelivertheinformationofdesign,processandengineeringtothedownstreamapplications.
简介:Thispaperpresentsanefficienttechniqueforprocessingof3Dmeshedsurfacesviasphericalwavelets.Morespecifically,aninput3Dmeshisfirstlytransformedintoasphericalvectorsignalbyafastlowdistortionsphericalparameterizationapproachbasedonsymmetryanalysisof3Dmeshes.Thissignalisthensampledonthespherewiththehelpofanadaptivesamplingscheme.Finally,thesampledsignalistransformedintothewaveletdomainaccordingtosphericalwavelettransformwheremany3Dmeshprocessingoperationscanbeimplementedsuchassmoothing,enhancement,compression,andsoon.Ourmaincontributionliesinincorporatingafastlowdistortionsphericalparameterizationapproachandanadaptivesamplingschemeintotheframeforprocessing3Dmeshedsurfacesbysphericalwavelets,whichcanhandlesurfaceswithcomplexshapes.Anumberofexperimentalexamplesdemonstratethatouralgorithmisrobustandefficient.
简介:Thispaperpresentsadirectmethodtofindtheinternalfaces.Itusesfoursetsofinformation:1getthecoordinatesofeachpointonthe3Dcompositeobjects;2basedonthe3Dcoordinatestocalculatealltheplaneequationoftwoobjects;3calculatealltheintersectinglinesofthetwoobjectsandexcludetheintersectinglineswhicharenotwithinthescopeoftheplane;4findingtheinternalface,theremainingintersectinglinesformedtheplaneistheinternalfaceofthetwoobjects.Weproposedanewalgorithmforfindinginternalfaces.Thisalgorithmcouldbeadaptedtoanyregularcompositeobjects.Thealgorithmworkswellforfindinginternalfaces.
简介:Aimingatachievingthehighaccuracy3Dmodelfromsliceimages,anewmodelreconstructionmethodusingsliceimagesisproposed.Wantingtoextracttheoutermostcontoursfromsliceimages,themethodoftheimprovedGVF-Snakemodelwithoptimizedforcefieldandraymethodisemployed.Andthen,the3Dmodelisreconstructedbycontourconnectionusingtheimprovedshortestdiagonalmethodandjudgmentfunctionofcontourfracture.Theresultsshowthattheaccuracyofreconstruction3Dmodelisimproved.
简介:A3D-viewishelpfultoinstantlygraspwhatispresentedinadrawing.Thereexistavarietyofwaystopresentthesamepartwith3D-views.Tofacilitatethechoiceofanoptimumoneamongthem,theworkdividescompositesolidmodelsintothreecategories,soastoconveytheoriginalityofdesignconciselyandaccuratelybyusingtheleast'engineeringlanguage'.