1、毕业设计(论文)外文资料翻译系别:专业:班级:姓名:学号:外文出处:附件:L原文;2.译文2013年03月附件一:ARapidlyDeployableManipulatorSystemChristiaanJJ.Paredis,H.BenjaminBrown,PradeepK.KhoslaAbstract:Arapidlydeployablemanipulatorsystemcombinestheflexibilityofreconfigurablemodularhardwarewithmodularprogrammingtools,allowingtheusertorapidlycreatea
2、manipulatorwhichiscustom-tailoredforagiventask.Thisarticledescribestwomainaspectsofsuchasystem,namely,theReconfigurableModularManipulatorSystem(RMMS)hardwareandthecorrespondingcontrolsoftware.1 IntroductionRobotmanipulatorscanbeeasilyreprogrammedtoperformdifferenttasks,yettherangeoftasksthatcanbeper
3、formedbyamanipulatorislimitedbymechanicalstructure.Forexample,amanipulatorwell-suitedforprecisemovementacrossthetopofatablewouldprobablynobecapableofliftingheavyobjectsintheverticaldirection.Therefore,toperformagiventask,oneneedstochooseamanipulatorwithanappropriatemechanicalstructure.Weproposetheco
4、nceptofarapidlydeployablemanipulatorsystemtoaddresstheabovementionedshortcomingsoffixedconfigurationmanipulators.AsisillustratedinFigure1,arapidlydeployablemanipulatorsystemconsistsofsoftwareandhardwarethatallowtheusertorapidlybuildandprogramamanipulatorwhichisCustomtailoredforagiventask.Thecentralb
5、uildingblockofarapidlydeployablesystemisaReconfigurableModularManipulatorSystem(RMMS).TheRMMSutilizesastockofinterchangeablelinkandjointmodulesofvarioussizesandperformancespecifications.OnesuchmoduleisshowninFigure2.Bycombiningthesegeneralpurposemodules,awiderangeofspecialpurposemanipulatorscanbeass
6、embled.Recently,therehasbeenconsiderableinterestintheideaofmodularmanipulators2,4,5,7,9,10,14,forresearchapplicationsaswellasforindustrialapplications.However,mostofthesesystemslackthepropertyofreconfigurability,whichiskeytotheconceptofrapidlydeployablesystems.TheRMMSisparticularlyeasytoreconfiguret
7、hankstoitsintegratedquick-couplingconnectorsdescribedinSection3.EffectiveuseoftheRMMSrequires,TaskBasedDesignsoftware.Thissoftwaretakesasinputdescriptionsofthetaskandoftheavailablemanipulatormodules;itgeneratesasoutputamodularassemblyconfigurationOptimallysuitedtoperformthegiventask.Several(Iifferen
8、tapproacheshavebeenusedsuccessfullytosolvesimpli-fiedinstancesofthiscomplicatedproblem.Athirdimportantbuildingblockofarapidlydeployablemanipulatorsystemisaframeworkforthegenerationofcontrolsoftware.Toreducethecomplexityofsoftwaregenerationforreal-timesensor-basedcontrolsystems,asoftwareparadigmcalle
9、dsoftwareassemblyhasbeenproposedintheAdvancedManipulatorsLaboratoryatCMU.Thisparadigmcombinestheconceptofreusableandreconfigurablesoftwarecomponents,asissupportedbyIheChimerareal-timeoperatingsystem15,withagraphicaluserinterfaceandavisualprogramminglanguage,implementedinOnikaAlthoughthesoftwareassem
10、blyparadigmprovidesthesoftwareinfrastructureforrapidlyprogrammingmanipulatorsystems,itdoesnotsolvetheprogrammingproblemitself.Explicitprogrammingofsensor-basedmanipulatorsystemsiscumbersomeduetotheextensiveamountOfdetailwhichmustbespecifiedfortherobottoperformthetask.Thesoftwaresynthesisproblemforse
11、nsor-basedrobotscanbesimplifieddramatically,byprovidingrobustroboticskills,thatis,encapsulatedstrategiesforaccomplishingcommontasksintherobotstaskdomain1l.SuchroboticskillscanthenbeusedatthetasklevelplanningstagewithouthavingtoconsideranyoftheIow-IeveldetailsAsanexampleoftheuseofarapidlydeployablesy
12、stem,consideramanipulatorinanuclearenvironmentwhereitmustinspectmaterialandspaceforradioactivecontamination,orassembleandrepairequipment.Insuchanenvironment,widelyvariedkinematic(e.g.,workspace)anddynamic(e.g.,speed,payload)performanceisrequired,andtheserequirementsmaynotbeknownapriori.Insteadofprep
13、aringalargesetofdifferentmanipulatorstoaccomplishthesetasks一anexpensivesolution-onecanusearapidlydeployablemanipulatorsystem.Considerthefollowingscenario:assoonasaspecifictaskisidentified,thetaskbaseddesignsoftwaredeterminesthetask.ThisoptimalconfigurationisthenassembledfromtheRMMSmodulesbyahumanor,
14、inthefuture,possiblybyanothermanipulator.TheFesultingmanipulatorisrapidlyprogrammedbyusingthesoftwareassemblyparadigmandourlibraryofroboticskills.Finally,themanipulatorisdeployedtoperformitstask.Althoughsuchascenarioisstillfuturistic,thedevelopmentofthereconfigurablemodularmanipulatorsystem,describe
15、dinthispaper,isamajorstepforwardtowardsourgoalofarapidlydeployablemanipulatorsystem.Ourapproachcouldformthebasisforthenextgenerationofautonomousmanipulators,inwhichthetraditionalnotionofsensor-basedautonomyisextendedtoconfiguration-basedautonomy.Indeed,althoughadeployedsystemcanhaveallthesensoryandp
16、lanninginfbrmationitneeds,itmaystillnotbeabletoaccomplishitstaskbecausethetaskisbeyondthesystem,sphysicalcapabilities.Arapidlydeployablesystem,ontheOtherhand,couldadaptitsphysicalcapabilitiesbasedontaskspecificationsand,withadvancedsensing,control,andplanningstrategies,accomplishthetaskautonomously.
17、2 Designofself-containedhardwaremodulesInmostindustrialmanipulators,thecontrollerisaseparateunithousingthesensorinterfaces,poweramplifiers,andcontrolprocessorsforallthejointsofthemanipulator.Alargenumberofwiresisnecessarytoconnectthiscontrolunitwiththesensors,actuatorsandbrakesIocatedineachofthejoin
18、tsofthemanipulator.Thelargenumberofelectricalconnectionsandthenon-extensiblenatureofsuchasystemlayoutmakeitinfeasibleformodularmanipulators.ThesolutionweproposeistodistributeIhecontrolhardwaretoeachindividualmoduleofthemanipulator.Thesemodulesthenbecomeself-containedunitswhichincludesensors,anactuat
19、or,abrake,atransmissionsensorinterface,amotoramplifier,andacommunicationinterface,asisillustratedinFigure3.Asaresult,onlysixwiresarerequiredforpowerdistributionanddatacommunication.2.1 MechanicaldesignThegoaloftheRMMSprojectistohaveawidevarietyofhardwaremodulesavailable.Sofar,wehavebuiltfburkindsofm
20、odules:themanipulatorbase,alinkmodule,threepivotjointmodules(oneofwhichisshowninFigure2),andonerotatejointmodule.Thebasemoduleandthelinkmodulehavenodegrees-of-freedom;thejointmoduleshaveonedegree-of-freedomeach.ThemechanicaldesignofthejointmodulescompactlyfitsaDC-motor,afail-safebrake,atachometer,ah
21、armonicdriveandaresolver.Thepivotandrotatejointmodulesusedifferentoutsidehousingstoprovidetheright-angleorin-lineConfigurationrespectively,butareidenticalinternally.Figure4showsincross-sectiontheinternalstructureofapivotjoint.EachjointmoduleincludesaDCtorquemotorand100:1harmonic-drivespeedreducer,an
22、disratedatamaximumspeedof1.5radsandmaximumtorqueof270Nm.Eachmodulehasamassofapproximately10.7kg.Asingle,compact,X-typebearingconnectsthetwojointhalvesandprovidestheneededoverturningrigidity.Ahollowmotorshaftpassesthroughalltherotarycomponents,andprovidesachannelforpassageofCablingwithminimalflexing.
23、2.2 ElectronicdesignThecustom-designedon-boardelectronicsarealsodesignedaccordingtotheprincipleofmodularity.EachRMMSmodulecontainsamotherboardwhichprovidesthebasicfunctionalityandontowhichdaughtercardscanbestackedtoaddmodulespecificfunctionality.ThemotherboardconsistsofaSiemens80C166microcontroller,
24、64KofROM,64KofRAM,anSMCCOM20020universallocalareanetworkcontrollerwithanRS-485driver,andanRS-232driver.ThefunctionofthemotherboardistoestablishcommunicationwiththehostinterfaceviaanRS-485busandtoperformtheIowlevelcontrolofthemodule,asisexplainedinmoredetailinSection4.TheRS-232serialbusdriverallowsfo
25、rsimplediagnosticsandsoftwareprototyping.Astackingconnectorpermitstheadditionofanindefinitenumberofdaughtercardswithvariousfunctions,suchassensorinterfaces,motorcontrollers,RAMexpansionetc.Inourcurrentimplementation,onlymoduleswithactuatorsincludeadaughtercard.Thiscardcontainsa16bitresolvertodigital
26、converter,a12bitA/DConvertertointerfacewiththetachometer,anda12bitD/AConvertertocontrolthemotoramplifier;wehaveusedanofthe-shelfmotoramplifier(GalilMotionControlmodelSSA-8/80)todrivetheDC-motor.Formoduleswithmorethanonedegree-of-freedom,forinstanceawristmodule,morethanonesuchdaughtercardcanbeStacked
27、ontothesamemotherboard.3 Integratedquick-couplingconnectorsTomakeamodularmanipulatorbereconfigurable,itisnecessarythatthemodulescanbeeasilyconnectedwitheachother.Wehavedevelopedaquick-couplingmechanismwithwhichasecuremechanicalconnectionbetweenmodulescanbeachievedbysimplyturningaringhandtighl;notool
28、sarerequired.AsshowninFigure5,keyedflangesprovidepreciseregistrationofthetwomodules.Turningofthelockingcollaronthemaleendproducestwodistinctmotions:firstthefingersofthelockingringrotate(withthecollar)about22.5degreesandcapturethefingersontheflanges;second,thecollarrotatesrelativetothelockingring,whi
29、leacammechanismforcesthefingersinwardtosecurelygripthematingflanges.Aball-transfermechanismbetweenthecollarandlockingringautomaticallyproducesthissequenceofmotions.Atthesametimethemechanicalconnectionismade,pneumaticandelectronicconnectionsarealsoestablished.Insidethelockingringisamodularconnectorth
30、athas30maleelectricalpinsplusapneumaticcouplerinthemiddle.Thesecorrespondtomatchingfemalecomponentsonthematingconnector.Setsofpinsarewiredinparalleltocarrythe72V-25Apowerformotorsandbrakes,and48V-6Apowerfortheelectronics.AdditionalpinscarrysignalsfortwoRS-485serialcommunicationbussesandfourvideobuss
31、es.Aplasticguidecollarplussixalignmentpinspreventdamagetotheconnectorpinsandassureproperalignment.TheplasticblockholdingIhefemalepinscanrotateinthehousingtoaccommodatetheeightdifferentpossibleconnectionorientations(845degrees).TherelativeorientationisautomaticallyregiSteredbymeansofaninfraredLEDinth
32、efemaleconnectorandeightphotodetectorsinthemaleconnector.4 ARMbuscommunicationsystemEachofthemodulesoftheRMMScommunicateswithaVME-basedhostinterfaceoveralocalareanetworkcalledtheARMbus;eachmoduleisanodeofthenetwork.ThecommunicationisdoneinaserialfashionoveranRS-485buswhichrunsthroughthelengthofthema
33、nipulator.WeusetheARCNETprotocol1implementedonadedicatedIC(SMCCOM20020).ARCNETisadeterministictoken-passingnetworkschemewhichHvoidsnetworkcollisionsandguaranteeseachnodeitstimetoaccessthenetwork.Blocksofinformationcalledpacketsmaybesentfromanynodeonthenetworktoanyoneoftheothernodes,ortoallnodessimul
34、taneously(broadcast).Eachnodemaysendonepacketeachtimeitgetsthetoken.Themaximumnetworkthroughputis5Mbs.Thefirstnodeofthenetworkresidesonthehostinterfacecard,asisdepictedinFigure6.InadditiontoaVMEaddressdecoder,thiscardcontainsessentiallythesamehardwareonecanfindonamodulemotherboard.Thecommunicationbe
35、tweentheVMEsideofthecardandtheARCNETsideoccursthroughdual-portRAM.Therearetwokindsofdatapassedoverthelocalareanetwork.Duringthemanipulatorinitializationphase,themodulesconnecttothenetworkonebyone,startingatthebaseandendingattheend-effector.Onjoiningthenetwork,eachmodulesendsadata-packettothehostinte
36、rfacecontainingitsserialnumberanditsrelativeorientationwithrespecttothepreviousmodule.Thisinfrmationallowsustoautomaticallydeterminethecurrentmanipulatorconfiguration.Duringtheoperationphase,thehostinterfaceCommunicateswitheachofthenodesat400Hz.Thedatathatisexchangeddependsonthecontrolmode-centraliz
37、edOrdistributed.Incentralizedcontrolmode,thetorquesfbrallthejointsarecomputedontheVME-basedreal-timeprocessingunit(RTPU),assembledintoadata-packetbythemicrocontrolleronthehostinterfacecardandbroadcastovertheARMbustoallthenodesofthenetwork.Eachnodeextractsitstorquevaluefromthepacketandrepliesbysendin
38、gadata-packetcontainingtheresolverandtachometerreadings.Indistributedcontrolmode,ontheotherhand,thehostcomputerbroadcaststhedesiredjointvaluesandfeed-forwardtorques.Locally,ineachmodule,thecontrolloopcanthenbeclosedataFrequencymuchhigherthan400Hz.Themodulesstillsendsensorreadingsbacktothehostinterfa
39、cetobeusedintheComputationofthesubsequentfeed-forwardtorque.5 ModularandreconfigurablecontrolsoftwareThecontrolsoftwarefortheRMMShasbeendevelopedusingtheChimerareal-timeoperatingsystem,Whichsupportsreconfigurableandreusablesoftwarecomponents15.ThesoftwarecomponentsusedtocontroltheRMMSarelistedinTabl
40、e1.Thetrjjline,dis,andgrav_compcomponentsrequiretheknowledgeofcertainconfigurationdependentparametersoftheRMMS,suchasthenumberofdegrees-of-freedom,theDenavit-Hartenbergparametersetc.Duringtheinitializationphase,theRMMSinterfaceestablishescontactwitheachofthehardwaremodulestodetermineautomaticallywhi
41、chmodulesarebeingusedandinwhichorderandOrientationtheyhavebeenassembled.Foreachmodule,adatafilewithaparametricmodelisread.Bycombiningthisinformationfbrallthemodules,kinematicanddynamicmodelsoftheentiremanipulatorarebuilt.Aftertheinitialization,thermmssoftwareComponentoperatesinadistributedcontrolmod
42、einwhichthemicrocontrollersofeachoftheRMMSmodulesperformPlDcontrollocallyat1900Hz.Thecommunicationbetweenthemodulesandthehostinterfaceisat400Hz,whichcandifferfromthecyclefrequencyofthermmssoftwarecomponent.Sinceweuseatriplebuffermechanism16forthecommunicationthroughthedual-portRAMontheARMbushostinte
43、rface,nosynchronizationorhandshakingisnecessary.BecauseclosedforminversekinematicsdonotexistforallpossibleRMMSconfigurations,weuseadampedleast-squareskinematiccontrollertodotheinversekinematicscomputationnumerically.6 SeamlessintegrationofsimulationToassisttheuserinevaluatingwhetheranRMMScon-figurat
44、ioncansuccessfullycompleteagiventask,wehavebuiltasimulator.ThesimulatorisbasedontheTeleGriprobotsimulationsoftwarefromDenebInc.,andrunsonanSGICrimsonwhichisconnectedwiththereal-timeprocessingunitthroughaBit3VME-to-VMEadaptor,asisshowninFigure6.AgraphicaluserinterfaceallowstheusertoassemblesimulatedR
45、MMSConfigurationsverymuchlikeassemblingtherealhardware.CompletedconfigurationscanbetestedandprogrammedusingtheTeleGripfunctionsforrobotdevices.TheconfigurationscanalsobeinterfacedwiththeChimerareal-timesoftwarerunningonthesameRTPUsusedtocontroltheactualhardware.Asaresult,itispossibletoevaluatenotonl
46、ythemovementsofthemanipulatorbutalsotherealtimeCPUusageandloadbalancing.Figure7showsanRMMSsimulationcomparedwiththeactualtaskexecution.7 SummaryWehavedevelopedaReconfigurableModularManipulatorSystemwhichcurrentlyconsistsofsixhardwaremodules,withatotaloffourdegrees-of-freedom.Thesemodulescanbeassembl
47、edinalargenumberofClifferentconfigurationstotailorthekinematicanddynamicpropertiesofthemanipulatortothetaskathand.ThecontrolsoftwarefortheRMMSautomaticallyadaptstotheassemblyconfigurationbybuildingkinematicanddynamicmodelsofthemanipulator;thisistotallytransparenttotheuser.Toassisttheuserinevaluating
48、whetheramanipulatorconfigurationiswellsuitedforagiventask,wehavealsobuiltasimulator.AcknowledgmentThisresearchwasfundedinpartbyDOEundergrantDE-F902-89ER14042,bySandiaNationalLaboratoriesundercontractAL-3020,bytheDepartmentofElectricalandComputerEngineering,andbyTheRoboticsInstitute,CarnegieMellonUni
49、versity.TheauthorswouldalsoliketothankRandyCasciola,MarkDeLouis,EricHoffman,andJimMoodyforIheirvaluablecontributionstothedesignoftheRMMSsystem.附件二:可迅速布置的机械手系统ChristiaanJ.J.Paredis,H.BenjaminBrown,PradeepK.Khosla摘要:一个迅速可部署的机械手系统,可以使再组合的标准化的硬件的灵活性用标准化的编程工具结合,允许用户迅速建立为一项规定的任务来通常地控制机械手。这篇文章描述这样的一个系统的两个主要方面,即,再组合的标准化的机械手系统(RMMS)硬件和相应控制软件。1介绍机器人操纵装置可能容易被程序重调执行不同的任务,然而一个机械手可以执行的任务的范围已经被它的机械结构限制。例如,一个很适合准确的运动的机械手在一张桌子上部或许将不能朝着垂直的方向举起重物。因此,执行规定的任务,需要有一个适宜的机械结构来选择机械手。