Decision Support System for Fighter Pilots

DecisionSupportSystemforFighterPilotsLarsRosenbergRandleffKongensLyngby2007IMM-PHD-2007-172TechnicalUniversityofDenmarkInformaticsandMathematicalModellingBuilding321,DK-2800KongensLyngby,DenmarkPhone+4545253351,[e-mail]fighteraircraftmaybeengagedbygroundbasedthreats.Thepilotcanusedifferentmeasurestoavoidtheaircraftfrombeingdetectedbye.g.enemyradarsystems.Iftheenemydetectstheaircraftamissilemaybefiredtoseekanddestroytheaircraft.Suchamissilewillalmostalwaysbeeitherradarguidedorheatseeking.Itwillbelaunchedfromapermanentlaunchpad,oritwillbemanportableandsmallenoughtofitinthebootofacar.Theprobabilityofamissilebeingdetectedbyon-boardsensorsdependsonthetypeofmissile.Ifamissileisdetectedthepilotmaychoosetodeployelectroniccountermeasurestoavoidtheimpactofthemissile.Thecountermeasurestochoosedependone.g.thetypeofmissileandguidancesystem,distanceanddirectionbetweenthemissileandtheaircraft,anassessmentoftheenvironmenthostility,aircraftaltitudeandairspeed,andtheavailabilityofcountermeasures.Radarsystems,guidanceofmissiles,andelectroniccountermeasuresareallpartsoftheelectronicwarfaredomain.Abriefdescriptionofthisdomainisgiven.Itcontainsanintroductiontobothsystemsworkingon-boardtheaircraftandcountermeasuresthatcanbeappliedtomitigatethreats.Thisworkisconcernedwithmethodsforfindingproperevasiveactionswhenafighteraircraftisengagedbygroundbasedthreats.Tohelpthepilotindecidingontheseactionsadecisionsupportsystemmaybeimplemented.Theenvironmentinwhichsuchasystemmustworkisdescribed,asaresomegeneralrequirementstothedesignofthesystem.Decisionssuggestedbythesystemarebasedoninformationacquiredfromdifferentsources.Theprocessofprovidinginformationfromsourcessuchasintelligence,on-boardsensorsystems,andiitacticaldatafromotherplatforms(aircraft,ships,etc.)isdescribed.Differentapproachestofindingthecombinationofcountermeasuresandma-noeuvresimprovingthesurvivabilityoftheaircraftareinvestigated.Duringtrainingafighterpilotwilllearnasetofrulestofollowwhenathreatoccurs.Forthepilottheseruleswillbeformulatedinnaturallanguage.Anexpertsys-temcanbebuildbytranslatingtheserulesintoalanguageunderstandablebyacomputerprogram.ThisisdoneinthedevelopmentofaPrologbaseddecisionsupportsystem.Afighteraircraftdecisionsupportsystemislikelytobaseitsdecisionsoninputfromnon-perfectsources.Warningsfromon-boardsensorsystemscanbefalseandintelligencereportsdeficient.ABayesiannetismodelledtoaddressthis.BuildingthedependencytablesofaBayesiannetrequiresalargenumberofcellstobefilledwithrelevantprobabilities.NothavingsufficientknowledgeabouttheseprobabilitiesmakestheworkwithdevelopingaBayesiannetcumbersome.Thereforeamethodforstructurallearningisinvestigated.HereaBayesiannetisbuildusingasetofsampledatafromanumberofmissileflightsimulations.Knowledgeaboutthreatsinthecurrentcombatscenariomayinfluencethechoiceofevasivemanoeuvresandpropercountermeasures.Ifatanygiventimemoreexpendablecountermeasuresaredispensedthannecessary,andnoneisleftforalaternecessity,thesurvivabilityoftheaircraftmaydecrease.Amathe-maticalmodelisdevelopedtodescribethisproblem.Itissolvedtooptimalityusingsolversoftware.Whennewthreatsoccurthedecisionsupportsystemmustbeabletoprovidesuggestionswithinafractionofasecond.Sincethetimeittakestofindanoptimalsolutiontothemathematicalmodelcannotcomplywiththisrequirementsolutionsaresoughtusingametaheuristic.Resum´eN˚aretjagerflyflyveroverfjendtligtomr˚ade,kandetbliveudsatforjordbaseredetrusler.Foratundg˚aatbliveopdagetaff.eks.fjendtligeradarsystemer,kanpi-lotenbenyttesigafforskelligemodmidler.Erflyetførstblivetopdaget,kanfjendenaffyremissilermoddet.S˚adanetmissilvilnæstenaltidværeen-tenradarstyretellervarmesøgende.Detkanbliveaffyretfraenpermanentaffyringsrampe,ellerdetkanværeskulderb˚arent,ogs˚alilleatdetkanskjulesibagagerummetp˚aenbil.Sandsynlighedenfor,atsensorerombordp˚aflyetkandetekteremissiletafhængerbl.a.afmissiletstype.N˚aretmissilerblevetdetekteret,kanpilotenvælgeatanvendemodmidlerforatundg˚a,atflyetbliverramtafmissilet.Hvilketmodmiddel,derskalvælgesafhængerbl.a.afmis-siltypen,hvordanmissileterstyret,afstandogretningmellemmissiletogflyet,enbedømmelseaf,hvorfjendtligeomgivelserneer,flyetshøjdeoghastighedogafhvilkemodmidlerderertilgængelige.Radarsystemer,styringafmissilerogelektroniskemodmidlerhøreralletilidomænetelektroniskkrigsførelse.Enkortbeskrivelseafdettedomæneergivether.Beskrivelsenindeholderb˚adeenintroduktiontilsystemerombordp˚aflyet,ogenbeskrivelseafdemodmidler,somkananvedesforatundg˚amissiler.Arbejdetbeskrevetidenneafhandlingg˚arudp˚aatfindeudaf,hvadpilotenskalforetagesign˚arflyetudsættesforjordbaseredetrusler.Idenforbindelsekanpilotenbenyttesigafetbeslutningsstøttesystem,derkanværeinstalleretijagerflyetscockpit.B˚adedenkonteksthvorietbeslutningsstøttesystemskalfungere,samtgenerellekravtildesignetafsystemeterbeskrevet.Systemetsbeslutningervilværebaseretp˚ainformationerfraforskelligekilder,ogprocessenmedatfremskaffeinformationerfraefterretningskilder,sensorsystemerombordp˚aflyetogtaktiskedatafr