附录A外文文献Alongwithautomobileelectronictechnologyswiftandviolentdevelopment,thepeoplealsodaybydayenhancetothemotorturninghandlingqualityrequest.Themotorturningsystemchanged,thehydraulicpressureboostfromthetraditionalmachinerychanges(HydraulicPowerSteering,iscalledHPS),theelectricallycontrolledhydraulicpressureboostchanges(ElectricHydraulicPowerSteering,iscalledEHPS),developstheelectricallyoperatedbooststeeringsystem(ElectricPowerSteering,iscalledEPS),finallyalsowilltransittothelinecontrolsthesteeringsystem(SteerByWire,willbecalledSBW).Themachinerysteeringsystemisrefersbypilot'sphysicalstrengthachievementchangestheenergy,inwhichallpowertransmissionallismechanical,theautomobilechangesthemovementisoperatesthesteeringwheelbythepilot,transmitsthroughthediverterandaseriesofmemberschangesthewheeltorealize.Themechanicalsteeringsystembychangesthecontrolmechanism,thediverterandmajorpartchangesthegearing3tobecomposed.Usuallymaydivideintoaccordingtothemechanicaldiverterform:Thegearracktype,followsroundtheworld-like,thewormbearingadjusterhooptype,thewormbearingadjusterreferssellsthetype.Isthegearracktypeandfollowsusingthebroadesttwokindsroundtheworld-like(usesinneedingtimebigsteeringforce).Infollowsroundtheworld-likeinthediverter,theinputchangesthecircleandtheoutputsteeringarmpivotangleisproportional;Inthegearracktypediverter,theinputchangestheturnandtheoutputrackdisplacementisproportional.Followsroundtheworld-likethediverterbecauseistherollingfrictionform,thusthetransmissionefficiencyisveryhigh,theeaseofoperationalsotheservicelifearelong,moreoverbearingcapacity,thereforewidelyappliesonthetruck.Thegearracktypediverterwithfollowsroundtheworld-likecompares,themostmajorcharacteristicistherigidityisbig,thestructurecompactweightislight,alsothecostislow.Becausethiswaypassesoneasilybythewheelthereactingforcetothesteeringwheel,thereforehastothepavementbehaviorresponsekeenmerit,butsimultaneouslyalsoeasytohavephenomenaandsoongoonandoscillation,alsoitsloadbearingefficiencyrelativeweak,thereforemainlyappliesonthecompactcarandthepickuptruck,atpresentthemajorityoflowendpassengervehicleusesisthegearracktypemachinerysteeringsystem.Alongwiththevehiclescarryingcapacityincreaseaswellasthepeopletothevehicleshandlingqualityrequestenhancement,thesimplemechanicaltypesteeringsystemwerealreadyunabletomeettheneeds,thepowersteeringsystemariseatthehistoricmoment,itcouldrotatethesteeringwheelwhilethepilottoprovidetheboost,thepowersteeringsystemdividesintothehydraulicpressuresteeringsystemandtheelectricallyoperatedsteeringsystem2kinds.Hydraulicpressuresteeringsystemisatpresentusesthemostwidespreadsteeringsystem.Thehydraulicpressuresteeringsystemincreasedthehydraulicsysteminthemechanicalsystemfoundation,includinghydraulicpump,Vshapebandpulley,drilltubing,feedinstallment,boostinstallmentandcontrolvalve.Itwiththeaidofinthemotorcarenginepoweractuationhydraulicpump,theaircompressorandthegeneratorandsoon,bythefluidstrength,thephysicalstrengthortheelectricpowerincreasesthepilottooperatethestrengthwhichthefrontwheelchanges,enablesthepilottobepossiblenimblytooperatemotorturningfacilely,reducedthelaborintensity,enhancedthetravelsecurity.Thehydraulicpressurebooststeeringsystemfrominventedalreadyhadabouthalfcenturyhistorytothepresent,mightsaywasonekindofmoreperfectsystem,becauseitsworkreliable,thetechnologymaturestillwidelyisapplieduntilnow.Ittakesthepowersupplybythehydraulicpump,afteroilpipe-linecontrolvalvestopowerhydrauliccylinderfeed,throughtheconnectingrodimpetusrotationgearmovement,maychangestheboostthroughthechangecylinderboreandtheflowingtubingheadpressuresizethesize,fromthisachievedchangestheboostthefunction.Thetraditionalhydraulicpressuretypepowersteeringsystemmaydivideintogenerallyaccordingtotheliquidflowform:Ordinaryflowtypeandatmosphericpressuretype2kindoftypes,alsomaydivideintoaccordingtothecontrolvalveformtransfersthevalvetypeandtheslide-valvetype.Alongwithhydraulicpressurepowersteeringsystemonautomobiledailypopularization,thepeopletooperateswhentheportabilityandtheroadfeelingrequestalsodaybydayenhance,howeverthehydraulicpressurepowersteeringsystemhasmanyshortcomingsactually:①Becauseitsitselfstructurehaddecideditisunabletoguaranteevehiclesrotatesthesteeringwheelwhenanyoperatingmode,allhastheidealoperationstability,namelyisunablesimultaneouslytoguaranteetimethelowspeedchangestheportabilityandthehighspeedtimeoperationstability;②Theautomobilechangesthecharacteristictodrivethepilottechnicaltheinfluencetobeserious;③Thesteeringratioisfixed,causesthemotorturningresponsecharacteristicalongwithchangesandsoonvehiclespeed,transverseaccelerationtochange,thepilotmustaimatthemotorturningcharacteristicpeak-to-peakvalueandthephasechangeaheadoftimecarriesoncertainoperationcompensation,thuscontrolstheautomobileaccordingtoitswishtravel.Likethisincreasedpilot'soperationburden,alsocausesinthemotorturningtravelnottohavethesecurityhiddendanger;Buthereafterappearedtheelectricallycontrolledhydraulicboostersystem,itincreasesthevelocitygeneratorinthetraditionalhydraulicpressu