基于嵌入式平台的智能小车控制器的设计的外文文献与翻译pdf

DesignofanIntelligentCarControllerBasedonEmbeddedPlatformLiuGangZhangQingyuWangYanlin(KeyLaboratoryofModernMeasurement&ControlTechnology（BeijingInformationScience&TechnologyUniversity），MinistryofEducation.)(BeijingInformationScience&TechnologyUniversityBeijing100192China)Abstract:ThepaperpresentsadesignofanintelligentcarcontrollerusingembeddedARM7chipsascorecomponent.Modularmethodhasbeenappliedinthedesignofthehardware;thepaperfocusesonlayoutoftrackingcircuitforthecaranddesignideasforthesoftware.Theexperimentresultprovesthatthedesignedintelligentcarisstableinoperationandgoodintrackingperformance.Keywords:ARMIntelligentTracking1、IntroductionInthe21stcentury,withdevelopmentofscienceandtechnology,researchesonintelligentcaranditscorrelativetechniqueshavebecomethefocusinthisfield.Aimingtoenhancepracticalability，innovation,andteamworkperformanceofcollegestudentsacrossthecountry,theEducationDepartmentsponsoredNationalUndergraduateIntelligentCarContest.Basedonthebackground,thepaperintroducesthedesignofmultifunctionalintelligentcarcontrolleronembeddedplatform,includingdesignofhardwarecircuitandsoftwareimplementationforkeyfunctionalmodules.2、DesignofhardwareByfunctionandapplication,thecontrollingplatformfortheintelligentcarisdividedintoseveralmodulesasshownbelow.2.1DesignofcoremoduleAT91SAM7S256microprocessorproducedbyATMELhasbeenadoptedforthecontrollerofthecar,whicha32-bitlow-powerRISCmicroprocessorchipbasedonARM7TDMI-Score,andembeddedwith64KBSARM,256KBhigh-speedFlashandJTAGportfordownloadingordebuggingoftheprogram.Asthecorecomponentofthecar,themicroprocessorplaysakeyroleincontrollingallrunningstatusesofthecar.PWMgeneratingmoduleinsideitcanbechangedutycycleofoutputtedsquarewavebyprogramming,andthuschangethevoltageloadedontheDCmotor,whichisamplifiedtocontroltherevolutionspeedofthemotor.TheportsPA0,PA1,PA2andPA3ofthePWMmodulerespectivelycontroltheDCmotorandthesteeringmotortoperformfunctionssuchasgoforward,retreatandturnetc.2.2DesignofpowermoduleThecarispoweredbyfourAAdrybatteries.Thevoltageisoutputtedthroughlow-NoiseLDOregulatorMIC5209-3.3tosupplypowerforARM7chipsandperipheralcircuits.TheworkingcurrentofMIC5209-3.3isashighas500mA.Wheninputvoltageisabove3.5V,themoduleofMIC5209-3.3canoutputstablevoltageof3.3Vandachievelowpowerconsumption.2.3TemperaturedetectionModuleMono-linedigitaltemperaturesensorDS18B20isusedtodetecttemperatureinthecar.Themeasurerangeisfrom-55℃to+125℃,withincrementof0.5℃.Itislowinpowerconsumptionandsmallinsize,occupyingonlyoneI/Oport.2.4Autotrackingmodule2.4.1PrinciplesfortrackingofintelligentcarTrackingmeansthatthecargoesalongthetwo-centimeter-wideblackguidelineonthewhitefloor.Infraredacquisitionandcamerashootingacquisitionarecommonlyusedforit.Infraredacquisition:Takingadvantageofthefeaturethatinfraredlightcanchangeitsreflectivequalityaccordingtoobjectsurfaceofvariouscolors.Duringrunningthecarcontinuouslysendsinfraredlighttotheground,whichwill,eitherbereflectedbackbythewhitefloorandreceivedbythereceivingtubeinthecar,orbeabsorbedbytheblackguidelineandthusmissedbythereceivingtube.Bythismeanstheblackguidelineispositionedtoidentifythepathforthecar.Camerashootingacquisition:Incertainresolutionsampletheimagebyinterlacedscanning.Whenscanningapoint,imagesensortransfersthegraythresholdintocorrespondingvoltagewhichwillbeoutputtedviavideosignalport.Asthecarachievesautotrackingbyrecognizingtheblackguidelineonthetrack,theimageprocessingisaprocessofextractingthedestinationguideline.Thetaskofimageprocessingprogramistoidentifythedotsintheblack-and-whiteimageandfilternoise,recorddotpositionsrelativetotheimage,andfinally,byalgorithmofcontrolstrategy,realizetrackingandturningofthecaralongtheguideline.2.4.2InstallationoftrackinginfraredprobeChoosingproperdetectionmethodandsensoristheimportantfactortoachievetracking.Herewechooseinfraredacquisition.Correctinstallationofdeviceisalsoadecisivefactorforaccomplishmentoftrackingcircuit.Intermsofsimplicity,easiness,practicalityandreliability,fourinfraredprobesneedbeinstalledonthefrontchassisofthecartofulfilltwo-stageddirectionalcorrectioncontroltoenhancethereliabilityoftracking.Fourtrackingsensorshavebeenfixed,allinoneline,amongwhichL1andR1areprimarysensorsfordirectioncontrol;L2andR2aresecondarysensors.Thedistancebetweenthetwoipsilateralsensorsshouldnorbemorethanwidthoftheblackdirectioncontrol.Whenthecarisrunning,theblackguidelineisalwayskeptrightbetweenthetwoprimarysensorsL1andL2.Whenthecargoesofftheblackline,theprimarysensorsdetectit,andthustheARM7chipdetectleveljumpandexecutethepre-preparedcorrectionprogramtonavigatethecarbackontothetrack.Thesecondarysensorsareactuallyaback-upfortheprimary.Oncethecaroffsetsthetrackforinertia,beyondthereachofdetectionoftheprimaryprobes,thesecondaryperformtocorrectthemotionofthecar,soastoensurethereliabilityoftracking.3DesignofsoftwareThesoftwareisdevelopedinClanguageinKeilUvision3IDE,debuggedanddownloadedinJ-LinkARMemulator.J-LinkisaJTAGemulatorwhichwasbroughtoutbySEGGERinUSAtosupportemulationchipswithARMcore.ItworkswithIDEssuchasIAREWARM,ADS,