【doc】Design of a Special PLC for Garbage Truck

1、design of a special plc for garbage truckvld.2no.1,march2011stnnno.5designofaspecialplcforgarbagetruck13ogao(高波),xiao-meii1an(欒曉梅)(collegeofinformationandelectricalengineering.shandonguniversityofscienceandtechnology,(ngdao266510,china)abstractaslcialplcisdesignedfortheeontrolsystemofgar?-bagetruck,

2、basedoilthefeatureandapplicationsofvehiculardectri-caldevice.thepijrp0seisdevelopingakindofmatureproductstocontrolthehydraulicsystem.thegeneraldesignplansaredescribed,indetail,andthedesignmintsareanalyzedandstnnmarized.keywoldsplc;gwbage臼cf(;singlechip;4ffcularelectronicsmanuscriptnlm】ber:16748042(2

3、011)01001304dio:10.3969/j.issn.16748042.2011.o1.041introductionwiththerapiddevelopmentofsocialeconomy,ur.banenvironmentalsanitationandrefusetransportequip.mentarerequiredtobeincreasinglyimproved.insomenaediunlandlargecitiesofourcountry,convertiblegar.bagetrucksaregraduallyeliminated,andreplacedbycom

4、pressionrefusecollector,rolloffgarbagetruck,etc.atpresent,someofcompressionrefusecollectormanufacturersformtheirownproductionanddevelop.mentcapacitythroughdigestingandabsorbingimportedtechnology,orbyimitationandappropriateinnovation,butsomeofthekeycomponentssuchashydraulicsystemandcontrolsystemetc.n

5、eedtobeimported.amongthem,controlsystemsalladoptimportedspecialprogram-mablelogiccontroller(plc)oruniversalplc,itscostishigherandtherearesomedefectsinthesystemt.therefore,basedonexistingtechnology,accordingtotheworkingconditionandcontrolrequirementofgar.bagetruck,thetopicofgarbagetruckspecialprogram

6、mablelogiccontrollerdesignisraised,thepur/xistode.signahighspecialty,low-cost,andhigh-reliabilitypro-grammableloglccontroller,andrealizeitsindustrializa.tioninordertoreplaceimportedproducts.themainresearchcontentsinclude:1)hardwareofspecialprogrammablelogiccontroller.whichcanbeusedonallkindsofgarbag

7、etruckprod.ucts;2)hand-holdwritingwhichcanwriteandreadpro.gramonsite;3)softwaresystem,whichincludessystemmonitorprogramandladderlogicprogrammingsystem.2thegeneraltechnologyschemethemainfunctionofspecialplcforgarbagetruckreceived:20100813q耵_啊h唱author:13ogao(gb005)istocontrolelectromagneticvalvestorea

8、chthepmxofcontrolmanipulatoraccordingtobuttonoperationorderofoperatorandcombinationwiththesignalstatefromswitchessuchastravelswitchesandproximityswitches.programmablelogiccontrollerissuppliedwithpowerbytruckbatteryorgenerator.atpresent,thecontrolsystemisanindependentsystem.whichnodatacommunicationne

9、edsfunctionintheprcwessofwork;thereservedcom.municationinterfaceisconvenientfordownloadinguserprogramsfromhostcomputerorhandholdprogrammer.inthefuturedevelopment,theplcwillprobablyneedtocommunicatewithothersystemsormaincontrollerofve.hicle,whichconstitutesabuscontrolsystemorachievesditalcontrol.theb

10、asiccompositionofplcisshowninfig.1fig.1basiccomtxitionofplc14journalofmeasurementscienceandinstrumentationno.120l11)hardwareparthardwarepartisthecorepartwhichdistinguishesspecialplcfromuniversalplc.thepartprocessesvehi.clepowersupply,processesinputandoutputaccordingtothedemandofvehicleequipment,also

11、includescpumoduleandcommunicationmodule.2)softwarepart111esoftwarepartisdividedintosystemmonitorpro.gramanduserprogram.systemmonitorprogramembedinasinglechipreadsriserprogramafterinitialization,andexecutecorrespondinginput,output1nstructions,etc.ac-cordingtouserprogramtoachievetheultimatefunctionofp

12、rogrammablelogiccontroller.3)programmingsystemprogrammingsystemisthatusereditsuserprogramonhostcomputerwithladderdiagramorinstructionlist,thenuserprogramcanbecompiledintohexformatanddownloadedtoplchardwareorhandholdprogrammer.2.2thebasicfunctionofprogrm'nrblelogiccontrolleraccordingtotheapplicat

13、ionrequirementsoffieldprogrammablecontrol,thebasicfunctionofprogramma.blelogiccontrollerdesignedisdividedintoinputprowess.rag,userprogramscan,outputprocessing,andalsoin-cludesauxiliarypowerprocessingandcommunicationfunction.theblockdiagramofbasicfunctionisshowninfig.2.fig.2blockdiagramofbasicfunctio

14、n1)inputprocessingbeforeprogramisexecuted.theon/offstatesofaljinputterminalsarereadtoinputimageregister.intheprocessofexecution,iodortsreceivethestatechangesofinputports,butthecontentofinputimageregisterisun-changed,thechangescannotbereaduntilthenextscanperiod.inaddition,input19ortsshouldreadstatema

15、nytimesatthesainescanperiodinordertoremovetheimpactofinterference.juserprogramscanprocessingforordersstoredinuserprogrammemory,theon/offstatesofrelatedsoftcomponentsarereadfrominputimageregister,thenoperationinorderstartsfromthefirststep,resultiswrittenintotherelevantimageregistereverytime,therefore

16、,thecontentofeveryimageregister(exceptinputrelay)isconstantlychangingwithprogramexecution.3)outputprocessingaftertheendofinstructionexecution,theon/offstatesofoutputimagereglsteraretransportedtooutputlatchregisterandbecomeactualoutputofprogrammablelogiccontroller.aboveinput/outputmodeiscalledbulkinp

17、ut/outputmode.3programmablelogiccontrollerhardwaredesigni11ecoreofprogranmblelogiccontrolleradoptsseriessinglechip,whichdossesses128kbytesofin-systemprogrammanefiash,upto8o00stepscanbestored,thereadingandwritingtimesistenthousand.111eframmemoryisusedtobeadata-holdingregisteronpower-off,whichcanreali

18、zehighspeeddatareadandwrite,maximunlbusfrequencyis1mhz,thereadingandwritingtimesis10,datacanberetainedupto45yearsonpoweroff.accordingtothequestionthatuniversajplchaspooradaptabilitytoharshcircumstances.aspecialhand.holdprogrammerisdeveloped,whichfunctionistostoreandwriteprograms.atthetimeofstorage,h

19、ostcomputerwritesuserprogramstoprogrammableashatthesamewaytooperateprogrammablelogiccontroller.forhostcomputer,therearenodifferencestowriteprogramsbetweentoprogrammablelogiccontrollerandtohand.holdprogrammer.whenprogramiswritten,handholdprogrammerisconnectedtoplcandsuppliespowerthroughtheserialport.

20、usercontrolsprogramtobewrit,vl01.213ogao,xiao-meiluantentoprograrnmablelogiccontrollerthroughbuttons.forprogrammablelogiccontroller,thereisnodifferencetowriteprogramsbetweenwithhostcomputerorwithwriter.1herefore.thecoreofhandholdprogrammeradoptsthesameplanandcomponentsasprogrammablelogiccontroller,t

21、hesinglechipprogramincreaseswritingfunc.tionbasedonprogrammablelogiccontrollermonitorprogram.workloadofdesignisgreatlysimplified.theworkingrangerequirementofvehiclepowersupply1swider,atthemstantofenginestarting,waveshockislarger,forthisreason,powersupplymoduleusesintegratedandwiderangeisolateddddcmo

22、dulewhichisspeciallyusedforvehicularelectroniccircuits,alsousestransientvoltagesuppressorandpp丁ctyperesettablefuse,themodulecanachievereliablepowerconversionandensurethatthecorecpuworksstablyandpreventr1_一powersourcereversalconnections引.3.20modulei/omodulecanbedividedintotwotyf,es:onetypeisbuttonorm

23、echanicaltravelswitchsigna1.anothertypeiselectronicproximityswitchsigna1.fortheformer,signalscanbedirectlyaccessedtophotocouplerafteracur.rentlimiting.forthelatter,thetypeofswitchsienalmustbetakenintoaccount,thatis,thetypeispnpornpn.whichisthequestionofcurrentflowdirection.someuniversalplccanacceptt

24、wo-waycurrentsignalsthroughinternalprocessing,thatistheinputoomportcanacceptpositivesignalornegativesigna1.comprehensivelyconsideredfactorssuchascostandreliabilityetc.colnltlonanodeleakageinputisused,thatis,suitableforcommonnpnsensor.3.3outputmoduleofprogrammablelogiccontrol-lerforgarbagetruckoutput

25、moduleofprogrammablelogiccontrollerforgarbagetruckisthekeyfactorwhichdecidesthestabilityandreliabilityoftheirlongtermoperation.i1hecontrolobjectisdcelectromagnetofelectromagneticvalve.workcurrentislargerandthereareshocksatthetimeofstart.toensurereliablework,maximumoutputcontrolcurrentshouldreach610a

26、.matureproductsinforeigncountriesgenerallyusespecialcontactrelaysforautomobile.butmaximumoutputsplcnedsareuptotwentyroads,sothesizeandweightofrelaysoccupyalargershare.withthedevelopmentofelectronictechnology.highpowerm0stubeshavebeeninoreandmorewidelyapplied,itcanmeetneedsofresistancetoshockcurrenta

27、ndhasadvantagessuchaslonglire,goodreliability,ef.fectiveprotectionofloads.self-recovery.smallsizeandsoon.thefuturedevelopmenttrendwillgraduallymakemostubesreplacecontactrelays.atpresent,packagetyperelayappliedinvehicularelectronichasappeared.therefore,thisdesignalsoadoptstheplanthatmostubeisadriver,

28、aftermature,fortheplan,engineeringverificationwillbecarriedout.3.4communicationmodulebeingdifferenttouniversalplc.applicationcondi.tionofplconvehicularissingle.tosimplifydesign.ac.cordingtopresentuserequirements,rs232interfaceisonlyretainedandachievedownloadingandreadofuserladderprogram(connectionwi

29、thhostcomputerorsceneprogrammer),atthesanletime,theinterfaceisacommunicationinterfacewhichconnectsuserprogramwithotherserialdevices.asavehicleproduct.thefuturedevelopmenttrendisthatcanbusisusedtoachieverealtimecommunicationanddatatransmission,whichconstitutesabuscontrolsystem.therefore.afterthereali

30、zationofpracticality,thatwillbetheaimofthenextprod.uctdevelopment.4programmingsystemandmonitorprogramthesoftwaredesignofprogrammablelogiccontro1.1ercontainsladderdiagramprogrammingsystemofhostcomputerandmonitorprogramwithinasinglechip.thefunctionisasfollows:programmingsystemconvertsuserprograminputt

31、edthroughladderdiagramorinstructionlistintohexformatdata;downloadinguserprogramtouserprogrammemorythroughsenalports;monitorpro?gramwithinasinglechipcircularlyreadsuserprogramandpertormscorrespondingoperationssuchasmput,output,logiccalculationandsoonaccordingtoitsimplicationinordertocompleteuserfunct

32、ion.thisisacomparativelygeneralway,thatis,theplanadoptedbydesignatpresent.thespecificdesignprocessisnoiongerdescribedindetail1,.anotherwayisonlytoadoptprogrammingsystemofhostcomputer.userprogramwillbedirectlyconvertedintosinglechipexecutableprogramaccordingtoafixedmodel,thendownloadedtosinglechippro

33、gramstorageareaandimplemented.thiswayhastheadvantagesofsimpleprogram,goodstabilityandsoon,butsomeset.tingsneedtobemadeaccordingtothecputypeofplcwhenprogramisdownloaded,whichmaycausesoftiepuzzlesforthefieldengineeringandtechnicalpersonnelwhouseplc.5plcsystemtestthedesignpurlxofswxfialplcisdevelopinga

34、kindofmatureproductswhichcanreplaceexistingimportproducts.so,itisnecessarytotestplcaccordingtona-tionalstandardsanduserneeds,accuratetechnicaiindexisobtainedinordertofurtherimprovedefaults.inaddit.iontorequirementssuchasworkinghours(theworktimesofrelays),inputpowersupplyindicator,controljournalofmea

35、surementscienceandimtrumentationno.12011objectsandsoon,plcproducta/soshouldcarryoutothertests.plcstabilityoflong-termworkistestedonconditionofhi【ghtemperatureorlowtemperature.i,ausegarbagetruckworksoutdoorsandenvironmenttempera-tureshavelargedifferenceswitidifferentworkcities,itshighandlowtemperatur

36、eperformancemustbeensured.thepc)seistotesttheeffectoftemperaturealternatingoilworkstabilityandmechanicalproperties.5.3vibrationtestthepurposeistotesttheeffectofsinemechanicalvibrationinfluenceonplccircuitboardelectricalandmechanicalpropertiesunderdifferentfrequencies.fortheplcmountedonmobilevehicle,

37、thisisanimportantindex.5.4droptestthepurposeistotestthedamagedropcausesollconditionofpackagingornon-packaging.asaproductdevelopment,servicelifeofslxcia/programmablelogiccontrollershouldbenolassthantenyears,theplccanadapttotheharshtropicalorcoldoutdoorclimate,forthisreason,theplcmustbetestedstrictlya

38、ndcomprehensivelytoensurethecorrectnessofdesignandeventuallybecomesaqualifiedproductforusers6conclusionaftercompletionofthedesign.accordingtotheex.istingimportedgarbagetrucktechnology,itscontrolpro-gramhasbeenrewrittenandcarriedoutfunctionalverifi.cationtest;testresultprovesthattheprogramcallmeetthefic._,osofcontro1.next.1ong-termworkstabilityandreliabilitywillbeverifiedunderavarietyofwor