An Autonomous Fire Fighting Robot

DeniseAnAutonomousFireFightingRobotProposalBySeanJusticeEEL5666August4,1999TableofContentsI.Abstractpage3II.ExecutiveSummarypage4III.Introductionpage5IV.IntegratedSystempage5V.MobilePlatformpage6VI.Actuationpage6VII.Sensorspage6VIII.Behaviorspage6IX.ExperimentalLayoutandResultspage7X.Conclusionpage7XI.Documentationpage7XII.Appendixpage7ABSTRACTDeniseisanautonomousrobotthatseeksoutfireandsignalswhereitis.Denisewillbeabletofirst‘smell’fire,andthenproceedtofindit.Therobotusedmicro-switches,twodifferenttypesofinfrareddetectorsandasmokedetectortofindthefireandmaneuverthroughrooms.Throughtheintegrationofthesesensors,Deniseabletorecognizewhenafirewaspresentandthensafetymaneuverandfindthefire.WhenDenisefoundthefire,shethenproceededtosignalwherethefirewas.EXECUTIVESUMMARYTherobotthatIcreatedwasanautonomousfire-seekingrobotnamedDenise.Therobotisabletodetectifthereisobjectsinfrontofit;ifithasbumpedintoawall;whetherthereissmokepresentandweatherthereisaflameinitsrange.Todothis,Iusedacombinationofsensorsalongwithprogrammingtobeablerecognizeandreacttoeachoftherespectedsituations.Forobstacleavoidance,Ineedtobeabletorecognizeiftherewasanobjectinfrontoftherobotandhowfaritwas.Ialsoneedtorecognizewhethertherobothasrunintoanobject,orifanobjecthasrunintoit.Tosuccessfullyaccomplishthis,Iusedtwotypesofsensors,micro-switchesandinfraredemittersanddetectors.Deniseisequippedwithsixmicro-switches.Threearelocatedinthefrontandthreearelocatedintheback.TheyareabletodetectifDenisehascomeintocontactwithanything.Iftheanyofthemicro-switchesareclosed,therobotwillknowthatithascomeintocontactwithanobjectandwillreactaccordingly.Deniseisalsoableto“see.”Denise’s“eyes”areactuallyfourinfraredemittersanddetectors.Theyarelocatedinthefrontandarepositionedsothattherearetwooneachside.Theinfraredsensorsworkbytheemitterssendingoutmodulatedwavelengths,whichtravelthroughtheair.Thewaveswillreflectoffofobjectsandbesentbacktothedetector.Thedetectorreturnsavoltagethatdependsontheamountofintensityofthewaves.Byusingtheinformationprovidedbythesetypesofsensors,therobotisabletoautonomouslywanderaboutaroom.Tobeabletogivetherobottheabilitytosenseiftherewassmokeandto“see”aflame,Iusedtwoothertypesofsensors.Torecognizethattherewassmokepresent,therobotwasequippedwithasmokedetector.Thesmokedetectorusingionizationtorecognizesmokeparticles.Thesmokedetectorwasintegratedintotherobottoalertit.Therobotwouldnotdoanythinguntilsmokewasdetected.Afterdetection,therobotwouldwanderaroundtheroomlookingforfire.Tofindthisfire,twoinfrareddetectorswereagainused.Thesedetectorsweredifferentthantoonesthantheonesusedforobstacleavoidance.Theinfraredsensorsdetectedwavelengthsthatwereemittedfromaflame.Theywerelocatedinthefrontoftherobot.Withtheusedofthesesensorsandprogramming,therobotwasabletorecognizeandreacttosmokeandfire.INTRODUCTIONBackgroundFightingfiresisaverychallenginganddangerousjob.Becauseofitslowpayandhighrisk,therearenotnearlyenoughfirefighterstomeetthedemand.ThisisrelevantinFlorida,primarilyinthesummerwhentherearemanybrushfirestheinstantlybrakeout.Firefightingisaverystressfuljob.Fire-peoplemustbeabletocopewithhighphysicaldemandsandhighmentalstress.Theymustbeabletoreactquicklyandefficientlytoextinguishthefireintheshortestamountoftime.Theymustmakethesequickchoiceswhenpeople’slivesareindanger.ScopeTheideaformyrobotcamefromthestressthatcancomefromfightingfire.Myrobot,Denise,couldresideinbuildings.Whenafirebreaksout,Denisecanstarttosearchandtrytosignalwherethefireislocated,whilethefirefightersareontheirway.Afterthefirefightersarrive,Denisecouldhelpthembysearchingotherroomsforfire.Myrobotwilldemonstratethesearchtheabilitytorecognizewhenafireispresent.Itwillthensearchandfindthefireandsignalswereitis.ToaccomplisheachofthesebehaviorsIwillusethefollowingsensors;infraredemittersanddetectors,micro-switches,andasmokedetector.AMotorola68HC11equippedsensorexpansionboardwillcontrolthesesensorsplusthecontrolofthemotors.INTEGRATEDSYSTEMDescriptionofSystemThe‘brain’ofDeniseisaMotorola68HC11.The68HC11havebeenexpandedsothatthereis64kofprogrammableRAM.Megatronixmakestheboardthatisusedinthisrobot.TheboardisthesameoneusedinTalrik,whichisarobotmadebyMegatronixaswell.TheboardisfairlysmallandprovidesmorethanenoughRAMformyapplications.Alongwiththemicroprocessorboard,Ialsousedasensorexpansionboard.Megatronixalsomakesthisboard.Thesensorexpansionboardhadmanyfeaturesthatwereveryhelpfulintheprogrammingoftherobot.Anotherboardthatwasusedintherobotwasatwo-amplifiercircuitusedfortheflamedetectors.OperationThefollowingblockdiagramshowshowtheintegratedsystemworks.IRdetector940nmIRdetector940nmIRdetector940nmIRdetector940nmIRdetector1000nmIRdetector1000nmSmokedetectorAmplifierforIRdetectorSensorExpansionBoardMicroprocessorwith64kofexpandedRAMRightMotorLeftMotorIRemitterIRemitterIRemitterIRemitterRearbumperFrontbumperTherobotuseseightanalogports,whichthesensorexpansionprovides.Thesensorexpansionboardactuallyhas20analogports,whichmakesiteasytoaddmoresensorstotherobot,ifdesiredlater.Themicroprocessorandsensorpackcanbestackedtored