高能量的激光建模与仿真框架分析（24）课件

AnalyzingaHighEnergyLaserModelingandSimulationFramework ComputerScienceDepartmentUnitedStatesNavalAcademyAnnapolis Maryland USA Midn1 CEricEckstrandSI495 Introduction Ourfocusisonend to endlasingsimulationsthatconsidersystemperformancemodeling assessmentofweaponeffectivenessfromvaryingperspectives Onesimulationprospective Followthephysicsofashipboardlaser senergystartingwith energyconversionfromtheship sfuel generationofthelaser slight beamtransport etc andendingwithilluminationontarget ProposedHELM Sarchitecturesmustfitintothishierarchy withdatatransferfacilitiesbetweenthelevelsasadesigngoal ThemilitaryM Shierarchypyramid Engineering EngagementModeling Notionalmethodologyforpassingphysics basedHighEnergyLaser HEL modelingresultsthroughtothemission modellevel TheRoleofSoftwareEngineering Collectionsofsuchsimulationsmustincludetheintegrationofavarietyoflaserdevices beamcontroltechnologies andprovideforatmosphericcompensationconsiderations andcanbeexpectedtocontainsignificantoverlapinfunctionality Softwarearchitecturesdevelopedforsuchsimulationsmustbe extensible andreusablesupportdatatransferbetweensimulationstofacilitatedatatraceability Domain Specific Domain Independent Application Specific 65 20 15 ThreeClassesofSoftwareinaTypicalSoftwareApplication Component basedsoftwareengineering Component basedsoftwareengineeringfocusesonconstructingsoftwarefrompreviouslyexistingcomponentsinanefforttoimprovereuse ToolkitssuchasCarnegieMellonUniversity sAesopSystemallowdeveloperstomitigatedisparitiesbetweenassumptionsmadeaboutareusablecomponentandthesysteminwhichthecomponentistobereused WeanalyzeNorthrupGrumman sHighEnergyLaserSimulationEnd to EndModeling HELSEEM frameworkdevelopedaspartoftheJTOHELM Sprogram TheHELSEEMframeworkprovidesamessage passingbasedarchitectureforintegratingdissimilarmodels andsupportstheinclusionofbothlegacyandemergentmodelingcodes NorthropGrumman sHELSEEM Suchframeworkscanbeeithermonolithicormodular MonolithicApproachNorthropGrumman sApproachModularApproachWhy HighEnergyLaserSoftwareSimulation Laser Target Sensor PropagationMethod HELSEEM Clock Modelingframeworkmustanticipatebothfuturerefinementstothewavepropagationmodelaswellastheemergenceofcompetitivemodelswithvaryinglevelsoffidelity HELSEEM sJointMessagePassingSystem Messagesonbusaredefinedbothbynameandbytheinformationcontainedinsidethemessage HELSEEMprovidesamessagepassingbus communicationprotocol andmessagebrokerthattogetherformtheJointMessagePassingSystem JMPS JMPSbusprovidescommbetweencomponentsinsim Eachcomponentwithintheframework includinguser definedcomponents samplesthebusformessagesitcanrespondto Differentcomponentscanbemaderesponsibleforgettingtheconditionsthatimpactbeamquality actuallycomputingthebeamquality andthendisplayingtheresultantbeam MessagePassingHierarchy Includingalasermodel scodeintotheframeworkisatwostepprocess andinvolvesbuildinga shell ofapropagationcomponentforthenewmodelandthenintegratingthemodelintotheshell TheJMPSprotocolsforpropagatingawavefrontcanbeviewedasamessagepassinginheritancehierarchy BlurPropagatorredefinesmethodsallowingforthedefaultintroductionofalowfidelityblureffectusedtocontroloutputtothedisplay Goal IntegratingLegacyLaserCodes OurgoalwastoconsiderthedifficultyofintegratinglegacylasercodeswithintheHELSEEMframework TheHELSEEMframeworkiswritteninWindows basedC andoffersbothitsownmodeloflaserpropagation aswellasprovidingitsuserswithareuse basedcapabilityofaugmentingtheframeworkwiththeirownmodelsoflaserpropagationWeincorporatedavariantofNPS sDr BillColson smodelforlaserwavefrontpropagationthroughtheatmosphereintotheHELSEEMframework PropagationComponent ProjectFocus ReplaceHELSEEM sdefaultpropagationcodewithDr Colson scode Laser Target Sensor PropagationMethod HELSEEMw Colson sprop Dr Colson sPropagationCode Clock Laser Target Sensor PropagationMethod HELSEEMw defaultpropagation Clock Colson smodelforlaserwavefrontpropagation CodeusedbyNPSphysicsgraduatestudentsaspartofintrotoFree ElectronLasercoursework Inputparametersdefinethepropagationenvironment UNIX basedCprogramgeneratesandprogressivelymanipulatesalaserwavefront Virtuallensesallowmodelingvariousconditionssuchasthermalblooming IncorporatingDr Colson sPropagationModel LegacyPropCode Inputfile initializationparameters OutputFile RepresentationOfapropagatedwave NewPropagator NewPropagatorw LegacyPropCode ScriptFile initializationparameters Approach 1LegacyCodeasExternalEntity Approach 2LegacyCoderewrittenasHELSEEMentity Laser Target Sensor HELSEEMw Colson sprop Clock 1 2 1stApproach LegacyCodeasExternalEntity Colson scodepropagateswavefrontbyincrementallymanipulatingbeam sunderlyingdatarepresentation Eachincrementpartiallypropagatesthewavefront andcanbeviewedasindividualslicesofthewavefront orinaggregateasa3Dviewofpathfromtransmissionsourcetotarget TreatedlegacycodeasanexternalentityratherthanrewritingthewavefrontpropagationsourcecodetocreateaHELSEEMcomponent 1stApproachLeavesLegacyCodeIntact CreateMicrosoftVisualC programtohousesystemcallstolegacycodewritteninCunderUnixMakesystemcalltolegacycodeinHELSEEMcomponent NewPropagator cpp ReadoutputoflegacyprogramandprocesstoaformunderstoodbyHELSEEM IntensityGrid PlacethegridinaHELSEEMmessageBroadcastthemessageviaJMPSmessagebrokernetwork Laser Target Sensor PropagationMethod Clock ScriptFile Display LegacyCode Output IntensityGrid LegacyCodeviaSystemCalls HELSEEMrepresentsalaser swavefrontasanintensitygridandaphasegrid withaone to onecorrelationbetweentheoutputproducedbythelegacycodeandtheinputrequiredbyHELSEEMframeworkforintensity Legacycodeminormodificationinordertoproduceoutputforphaseanglesofeachcomplexentryingrid Requiredpre processingtopreparegridforentryintoJMPSmessagebroker AdvantagesofLegacyCodeasExternalEntity Invokingthelegacycodeviasystemorremotecallsallows minimizationofcodetransferfromthelegacycodetothecorrespondingHELSEEMcomponent andtheabilitytorunawavefront spropcodeondisparatehardware The2ndapproachwetookwastorewritethelegacycodetoallowitsinclusionasaselfcontainedHELSEEMcomponent 2ndApproach ConvertLegacyCodetoHELSEEMComponent Convertlegacycode sCfunctionsintoC functionsMovethefunctionsandvariablesintotheNewPropagatorclass ConvertedLegacyCode below asprivatemembersNewPropagatorclassdesignedtoacceptinputfromascriptfileWritethescriptfilesectionthatinputstheinitializationparameters 2ndApproach LegacyasHELSEEMentity Advantageouswhenthelegacycodetakesonmoreresponsibilitythanjustwavefrontpropagation Inourcase wehadcodethatgeneratesaninitialbeamandalsocontainsthemodelforpropagatingthebeam WithinHELSEEM generatingawavefrontshouldbetheresponsibilityofacomponentwithintheframeworksincegenerationdependsonthecharacteristicsofthelaserwhichshouldnotbevisibletotheothercomponents Disadvantages Notalllegacycodecanbeeasilyre written Legacycodemayrunfasterondissimilararchitecture AdvantagesprovidedbytheHELSEEMFramework HELSEEM sadvantagescenteraroundtheabilitytocommunicatewithanycomponentbybroadcastingamessageviathebroker Frameworksupportstheabilitytowriteadditionalcomponentsthattransformonemessage scontentstoadifferentformatwhichtendstomitigatedatamodeldisparityissues Tookthisroutewithour2ndapproachinordertocomputephaseanglesthatHELSEEM sdisplaycomponentscouldrecognize Suggeststhatamessagearbitratorwouldbeusefulto determinewhichmessagesacomponentmay orshould respondto especiallywheremorethanonecomponentcanbeexpectedtoactonthesamemessage AdvantagesprovidedbytheHELSEEMFramework OtheradvantagesprovidedbyHELSEEM sapproachincludesupportfromtheframeworkfortheusertotailortheoutput Forexample thelegacycode spropagationcanbeviewedasaseriesoftwodimensionalslicesofthelaser swavefront Userscanaddtheirownuser defineddisplaycomponentstotheframework Thesecomponentscoulddisplaya3Dviewofthebeamduringpropagation orpresenttablesnumericallydepictingthecomputedintensityofthebeamatanyorallpointsalongpropagationpath ThisextensibilitymakesHELSEEMparticularlyvaluableforend to endsimulations AreasofImprovement TheeasewithwhichlegacypropagationcodescanbemadetointeractwiththeHELSEEMframework IfHELSEEMweremodifiedtosupportgeneralizedwrapperclassesdesignedforintegrationwithlaserpropagationcodes muchoftheeffortneededtointegratelegacycodewouldbediminished SuchwrapperclasseswouldneedaninterfacethatHELSEEMcouldexpecttodynamicallyinvoke Thelegacycodewouldthenneedtobetiedinonlywiththewrapperclass leavinglittleknowledgerequiredonthepartoftheuserregardingtheinnerworkingsoftheHELSEEMframework Thisrequirestheidentificationofasuper setofmethodsanddatausedinend to endhighenergylasersimulations AreasofImprovement Wefoundthatwhilethehierarchyofcomponentscapableofrespondingtouser definedJMPSmessagesisreadilyexpandable theunderlyingdatamodelissomewhatlimitedwithregardtowhatdatacanbeplacedinamessage Wecannot forexample sendamessagedirectlytoadisplaycomponentthatcontainsinformationthatdescribeshowthepropagatingwavefrontlooksonatarget butmustinsteadfollowtheHELSEEMmessagepassingprotocolsthoughwhichthedataismanipulatedaccordingtothecomponent s receivingandactinguponthemessage Astandardizedbutexpandabledatamodelwouldprovebeneficialforend to endsimulations Conclusions Simulationenvironmentsthatsupportintegrationandsubstitutionoflasermodelingcodesofvaryingfidelityarerequiredforhighenergylaserend to endsimulations NorthropGrumman sHELSEEMframeworksupportstracingalaser senergyfromi