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英文原文MECHANISMSANDMACHINETHEORY1INTRODUCTIONTOMECHANISMTHEFUNCTIONOFAMECHANISMISTOTRANSMITORTRANSFORMMOTIONFROMONERIGIDBODYTOANOTHERASPARTOFTHEACTIONOFAMACHINETHEREARETHREETYPESOFCOMMONMECHANICALDEVICESTHATCANBEUSEDASBASICELEMENTSOFAMECHANISM1、GEARSYSTEM,INWHICHTOOTHEDMEMBERSINCONTACTTRANSMITMOTIONBETWEENROTATINGSHAFTS2、CAMSYSTEM,WHEREAUNIFORMMOTIONOFANINPUTMEMBERISCONVERTEDINTOANONUNIFORMMOTIONOFTHEOUTPUTMEMBER3、PLANEANDSPATIALLINKAGESAREALSOUSEFULINCREATINGMECHANICALMOTIONSFORAPOINTORRIGIDBODYAKINEMATICCHAINISASYSTEMOFLINKS,THATIS,RIGIDBODIES,WHICHAREEITHERJOINTEDTOGETHERORAREINCONTACTWITHONEANOTHERINAMANNERTHATPERMITSTHEMTOMOVERELATIVETOONEANOTHERIFONEOFTHELINKSISFIXEDANDTHEMOVEMENTOFANYOTHERLINKTOANEWPOSITIONWILLCAUSEEACHOFTHEOTHERLINKSTOMOVETODEFINITEPREDICTABLEPOSITION,THESYSTEMISACONSTRAINEDKINEMATICCHAINIFONEOFTHELINKSISHELDFIXEDANDTHEMOVEMENTOFANYOTHERLINKTOANEWPOSITIONWILLNOTCAUSEEACHOFTHEOTHERLINKSTOMOVETOADEFINITEPREDICTABLEPOSITIONTHENTHESYSTEMISANUNCONSTRAINEDKINEMATICCHAIN,AMECHANISMORLINKAGEISACONSTRAINEDKINEMATICCHAIN,ANDISAMECHANICALDEVICETHATHASTHEPURPOSEOFTRANSFERRINGMOTIONAND/ORFORCEFROMASOURCETOANOUTPUTALINKAGECONSISTSOFLINKSORBARS,GENERALLYCONSIDEREDRIGID,WHICHARECONNECTEDBYJOINTS,SUCHASPINCORREVOLUTEORPRISMATICJOINTS,TOFORMOPENORCLOSEDCHAINSORLOOPSSUCHKINEMATICCHAINS,WITHATLEASTONELINKFIXED,BECOMEMECHANISMSIFATLEASTTWOOTHERLINKSREMAINMOBILITY,ORSTRUCTURESIFNOMOBILITYREMAINSINOTHERWORDS,AMECHANISMPERMITSRELATIVEMOTIONBETWEENITSRIGIDLINKS；ASTRUCTUREDOESNOTSINCELINKAGESMAKESIMPLEMECHANISMSANDCANBEDESIGNEDTOPERFORMCOMPLEXTASKS,SUCHASNONLINEARMOTIONANDFORCETRANSMISSIONTHEYWILLRECEIVEMUCHATTENTIONINMECHANISMSTUDYMECHANISMSAREUSEDINAGREATVARIETYOFMACHINESANDDEVICESTHESIMPLESTCLOSEDLOOPLINKAGEISTHEFOURBARLINKAGE,WHICHHASTHREEMOVINGLINKSPLUSONEFIXEDLINKANDFOURPINJOINTSTHELINKTHATISCONNECTEDTOTHEPOWERSOURCEORPRIMEMOVERANDHASONEMOVINGPIVOTANDONEGROUNDPIVOTISCALLEDTHEINPUTLINKTHEOUTPUTLINKCONNECTSANOTHERMOVINGPIVOTTOANOTHERGROUNDPIVOTTHECOUPLERORFLOATINGLINKCONNECTEDTHETWOMOVINGPIVOTS,THEREBYCOUPLINGTHEINPUTTOTHEOUTPUTLINKTHEFOURBARLINKAGEHASSOMESPECIALCONFIGURATIONSCREATEDBYMAKINGONEORMORELINKSINFINITEINLENGTHTHESLIDERCRANKORCRANKANDSLIDERMECHANISMISAFOURBARCHAINWITHASLIDERREPLACINGANINFINITELYLONGOUTPUTLINKTHEINTERNALCOMBUSTIONENGINEISBUILTBASEDONTHISMECHANISMOTHERFORMSOFFOURLINKMECHANISMSEXISTINWHICHASLIDERISGUIDEDONAMOVINGLINKRATHERTHANONAFIXEDLINKTHESEARECALLEDINVERSIONSOFTHESLIDERCRANK,PRODUCEDWHENANOTHERLINKTHECRANK,COUPLER,ORSLIDERISFIXEDLINKALTHOUGHTHEFOURBARLINKAGEANDSLIDERCRANKMECHANISMAREVERYUSEFULANDFOUNDINTHOUSANDSOFAPPLICATIONS,WECANSEETHATTHESELINKAGESHAVELIMITEDPERFORMANCELEVELLINKAGESWITHMOREMEMBERSAREOFTENUSEDINMOREDEMANDINGCIRCUMSTANCESHOWEVERITISOFTENDIFFICULTTOVISUALIZETHEMOVEMENTOFAMULTILOOPLINKAGE,ESPECIALLYWHENOTHERCOMPONENTSAPPEARINTHESAMEDIAGRAMTHEFIRSTSTEPINTHEMOTIONANALYSESOFMORECOMPLICATEDMECHANISMSISTOSKETCHTHEEQUIVALENTKINEMATICORSKELETONDIAGRAMTHESKELETONDIAGRAMSERVESAPURPOSESIMILARTOTHATOFTHEELECTRICALSCHEMATICORCIRCUITDIAGRAMORGANIZATIONMOVEMENTANALYSISSECONDSTEPDRAWSAGRAPHICCHART,ISMUSTDETERMINETHEORGANIZATIONTHENUMBEROFDEGREESOFFREEDOMBASEDONDEGREEOFFREEDOM,BUTITALYREFERSNEEDSCERTAININDEPENDENTINPUTSTHEMOVEMENTNUMBER,BYDETERMINEDORGANIZATIONALLCOMPONENTSAREOPPOSITEINTHEGROUNDPOSITIONTHEPEOPLEHAVETHOUSANDSOFDIFFERENTTYPESCONCEIVABLYTHELINKMOTIONGEARYOUMAYIMAGINEABAGCONTAININGMASSIVELINKMOTIONGEARTHECOMPONENTTWOPOLEGROUPS,THREEPOLEGROUPS,FOURPOLEGROUPSANDSOON,ASWELLASCOMPONENTS,ROTATION,MOTION,CAMFOLLOWER,GEAR,TOOTHCHAIN,CHAINWHEEL,LEATHERBELT,BELTPULLEYANDSOONSPHEREMOVEMENT,SCREWVICEASWELLASTHEPERMISSIONTHREEDIMENSIONALRELATIVEMOTIONOTHERCONNECTIONSNOTYETINCLUDES,HERE,DISCUSSESINPARALLELPLANESMERELYPLANEMOTIONMOREOVERYOUCONCEIVABLEPUTTHESECOMPONENTSVARIOUSTYPESLINKMOTIONGEARPOSSIBILITYWHICHFORMSINTHESAMEPLACEHOWEXISTSHELPSTHEPEOPLETOCONTROLFORMSTHESEORGANIZATIONSTHERULEINFACT,THEMAJORITYORGANIZATIONDUTYISREQUESTSASOLEINPUTTOTRANSMITTOASOLEOUTPUTTHEREFORETHESINGLEDEGREEOFFREEDOMORGANIZATIONUSESMOSTONEKINDOFORGANIZATIONTYPEFOREXAMPLE,NAMELYMAYSEEBYTHEINTUITIONFOURPOLEORGANIZATIONSAREASINGLEDEGREEOFFREEDOMLINKMOTIONGEARTHEPICTUREMOTIONDIAGRAMANDTHEDETERMINATIONORGANIZATIONDEGREEOFFREEDOMPROCESS,ISTHEMOVEMENTANALYSISANDTHESYNTHESISPROCESSFIRSTSTAGEINTHEMOVEMENTANALYSIS,ADDSONITSCHARACTERISTICACCORDINGTOTHEORGANIZATIONGEOMETRYSHAPEWHICHPOSSIBLYKNEWFOREXAMPLEINPUTANGLE,SPEED,ANGLEACCELERATIONANDSOONSTUDIESTHEDETERMINATIONCONCRETEORGANIZATIONONTHEOTHERHAND,THEMOVEMENTSYNTHESISISDESIGNSANORGANIZATIONTOCOMPLETETHEDUTYPROCESSWHICHANINSTITUTEREQUESTSINTHIS,CHOOSESTHENEWORGANIZATIONTHETYPEANDTHESIZEISAMOVEMENTSYNTHESISPARTCONCEIVESTHERELATIVEMOTIONABILITY,CANGUESSTHEREASONTHATDESIGNSANORGANIZATIONTHEREASONANDMAKESTHEIMPROVEMENTTOACONCRETEDESIGNABILITYISLIKETHISASUCCESSFULORGANIZATIONSCIENTISTSSYMBOLALTHOUGHTHESEABILITIESCOMEFROMTHECONGENITALCREATIVITY,HOWEVERMOREISBECAUSEHASGRASPEDTHETECHNOLOGYWHICHENHANCESFROMTHEPRACTICE11THEMOVEMENTANALYSISSIMPLEONEOFMOSTUSEFULORGANIZATIONSISFOURPOLEORGANIZATIONSINONFOLLOWINGELABORATIONMAJORITYOFCONTENTCENTRALISMDISCUSSIONLINKMOTIONGEAR,BUTTHISPROCEDUREISALSOSUITABLEFORTHEMORECOMPLEXLINKMOTIONGEARWEALREADYKNEWFOURPOLEORGANIZATIONSHAVEADEGREEOFFREEDOMABOUTFOURPOLEORGANIZATIONS,HASTHEUSEFULMORECONTENTSWHICHMUSTKNOWINDEEDISSOMETHESEPULLTHEXIAOHUSBANDCRITERIONINCLUDINGTHESTANDARD,THETRANSFORMATIONCONCEPT,THEBLINDSPOTPOSITIONDIVERGENCEPOINT,BRANCHOFFICE,TRANSMISSIONANGLE,WITHTHEIRSMOVEMENTCHARACTERISTIC,INCLUDINGPOSITION,SPEEDANDACCELERATIONFOURPOLEORGANIZATIONSMAYHAVEONEKINDOFBEINGCALLEDASCRANKROCKERORGANIZATIONFORM,ONEKINDOFDOUBLEROCKINGLEVERORGANIZATION,ONEKINDOFDOUBLECRANKTENSIONBARDOESTHEORGANIZATION,WHICHONEFORMSENDINISCALLEDASTHEORGANIZATION,ISDECIDEDINTWOPOLEMOVEMENTSCOPESWHICHFIXEDCOMPONENTCONNECTSWITHTHERACKTHECRANKROCKERORGANIZATIONINPUTCOMPONENT,THECRANKMAYREVOLVETHROUGH360ANDTHECONTINUOUSROTATION,BUTOUTPUTSTHECOMPONENTTOMAKETHEUNDULATIONMERELYIESWINGMEMBERASANEXCEPTIONALCASE,INTHEPARALLELFOURPOLEORGANIZATION,INPUTSTHEPOLETHELENGTHTOBEEQUALTOOUTPUTSTHEPOLETHELENGTH,THEGOBETWEENLENGTHANDTHEFIXEDLINKRACKLENGTH,ALSOISEQUALITSINPUTANDTHEOUTPUTALLMAYMAKETHECOMPLETEALTERNATIONROTATIONORTRANSFORMTHEBEINGCALLEDASANTIPARALLELQUADRANGLEORGANIZATIONTHEOVERLAPPINGSTRUCTURETHESTANDARDPULLSTHEXIAOHUSBANDCRITERIONTHEOREMTOINDICATETHAT,IFINFOURPOLEORGANIZATIONS,BETWEENTWOPOLESCANDOWILLFULLYRELATIVELYROTATESCONTINUOUSLY,THAT,ITSLONGESTPOLELENGTHISSMALLERTHANSUMOFWITHTHESHORTESTPOLELENGTHORISEQUALTOSUMOFTHEOTHERTWOPOLELENGTHSHOULDPAYATTENTIONTHESAMEFOURPOLEORGANIZATION,MAYHAVETHEDIFFERENTFORM,WHICHPOLEISTHISDECIDEDINWASSTIPULATEDIEMAKESFIXEDLINKASTHERACKTHEMOVEMENTTRANSFORMATIONPROCESSISINTHEFIXEDORGANIZATIONTRANSMISSIONCHAINDIFFERENTMEMBERHASTHEDIFFERENTORGANIZATIONRATEPROCESSBESIDESHASABOUTTHECOMPONENTROTATIONSCOPEKNOWLEDGE,BUTALSOMUSTHAVEHOWCAUSESTHEORGANIZATIONBEFORETHEMANUFACTUREONENERGY“THEREVOLUTION”THEGOODMEASURE,THATWILLBEVERYUSEFULHARDENBERGHHARTENBERGSPEAKSOF“THEREVOLUTION”ISTERMINOLOGY,ITSSIGNIFICANCEPASSESTOOUTPUTSTHECOMPONENTTHEMOVEMENTVALIDITYITMEANTTHEREVOLUTIONISSTEADY,INWHICHCANINOUTPUTINTHECOMPONENTTOHAVEASTRENGTHORTHETORQUEBIGGESTFORCECOMPONENTISEFFECTIVENOTONLYALTHOUGHTHEFINALOUTPUTSTRENGTHORTHETORQUEARETHECONNECTINGRODGEOMETRICFIGUREFUNCTIONS,MOREOVERALSOISGENERALLYTHEPOWERORTHEFORCEOFINERTIARESULT,THATISFREQUENTLYBIGTOLIKESTATICSTRENGTHSEVERALTIMESINORDERTOANALYZETHEIDLINGORINORDERTOEASYTOOBTAINHOWCANCAUSEANYORGANIZATION“THEREVOLUTION”THEINDEX,THETRANSMISSIONANGLECONCEPTISEXTREMELYUSEFULINORGANIZATIONMOVEMENTPERIOD,THETRANSMISSIONANGLEVALUEISCHANGINGTHETRANSMISSIONANGLE0MAYOCCURINTHESPECIALPOSITIONWILLOUTPUTTHEPOLEBUTINTHISSPECIALPOSITIONTHEMOVEMENTWITHNOTTOEXERTINPUTSONTHEPOLETHESTRENGTHMANYTOHAVENOTHINGTODOWITHGREATLYINFACT,ASARESULTOFTHEMOVEMENTVICEFRICTIONINFLUENCE,THEGENERALBASISPRACTICALEXPERIENCE,WITHTHETRANSMISSIONANGLEPLANNINGBOARDWHICHISBIGGERTHANTHERATINGTHEWEIGHTLINKMOTIONGEARTRANSMISSIONMOVEMENTABILITYMATRIXFOUNDATIONDEFINITIONALREADYSTUDIEDADETERMININGFACTORVALUEITINCLUDESREGARDINGSOMEASSIGNSORGANIZATIONGRAPH,POSITIONOUTPUTMOVEMENTVARIABLETOINPUTVARIABLEDERIVATIVEISATHISLINKMOTIONGEARINCONCRETEPOSITIONMOBILITYCRITERIONIFTHEORGANIZATIONHASADEGREEOFFREEDOMEGFOURPOLEORGANIZATIONS,THENSTIPULATEDALOCATIONPARAMETER,IFTHEINPUTANGLE,COMPLETELYDETERMINEDTHISORGANIZATIONSTOPSPOSITIONNEGLECTBRANCHOFFICESPOSSIBILITYWEMAYSTUDYONEABOUTFOURPOLEORGANIZATIONCOMPONENTABSOLUTEANGULARPOSITIONANALYSISEXPRESSIONWHENANALYZESCERTAINPOSITIONSANDORCERTAINDIFFERENTORGANIZATIONTIME,THISWILLBEMUSTBEMUCHMOREUSEFULTHANTHEGEOMETRICFIGUREANALYSISPROGRAM,BECAUSETHISEXPRESSIONWILLCAUSETHEAUTOMATEDCOMPUTATIONEASYTOPROGRAMTHEREALIZATIONORGANIZATIONSPEEDANALYSISRELATIVEVELOCITYLAWISTHESPEEDPOLYGONISONEOFSEVERALEFFECTIVEMETHODSTHISENDGOESAGAINSTTHESPOTTOREPRESENTONTHE
