轻量级丝杠作动器设计在便携的机器人的应用毕业课程设计外文文献翻译、中英文翻译、外文翻译

DESIGNOFLIGHTWEIGHTLEADSCREWACTUATORSFORWEARABLEROBOTICAPPLICATIONSJOURNALOFMECHANICALDESIGNKEVINWHOLLANDERTHOMASGSUGARAWEARABLEROBOTISACONTROLLEDANDACTUATEDDEVICETHATISINDIRECTCONTACTWITHITSUSERASSUCH,THEIMPLIEDREQUIREMENTSOFTHISDEVICEARETHATITMUSTBEPORTABLE,LIGHTWEIGHT,ANDMOSTIMPORTANTLYSAFETOACHIEVETHESEGOALS,THEDESIGNOFTHESTANDARDLEADSCREWDOESNOTNORMALLYPERFORMWELLINANYOFTHESECATEGORIESTHETYPICALLEADSCREWHASLOWPITCHANGLESANDLARGERADII,THEREBYYIELDINGLOWMECHANICALEFFICIENCIESANDHEAVYWEIGHTHOWEVER,USINGTHEDESIGNPROCEDUREOUTLINEDINTHISTEXT,BOTHEFFICIENCYANDWEIGHTAREIMPROVEDTHUSYIELDINGALEADSCREWSYSTEMWITHPERFORMANCESTHATRIVALHUMANMUSCLETHERESULTOFANEXAMPLEPROBLEMREVEALSAFEASIBLELEADSCREWDESIGNTHATHASAPOWERTOWEIGHTRATIOOF277W/KG,APPROACHINGTHATOFTHEDCMOTORDRIVINGIT,AT312W/KG,ASWELLASAMECHANICALEFFICIENCYOF074,ANDAMAXIMUMSTRENGTHTOWEIGHTRATIOOF113KN/KG。1INTRODUCTIONONEINFIVEPERSONSINTHEUNITEDSTATESLIVEWITHSOMEFORMOFDISABILITY,WITH61OFTHOSESUFFERINGFROMEITHERASENSORYORPHYSICALDISABILITYASANEXAMPLE,WITHINTHEELDERLYPOPULATION,8TO19AREAFFECTEDBYGAITDISORDERSMANYDISABLEDINDIVIDUALSCOULDBENEFITFROMSOMEFORMOFROBOTICINTERVENTIONAWEARABLEROBOTISACOMPUTERCONTROLLEDANDACTUATEDDEVICETHATISINDIRECTCONTACTWITHITSUSERTHEPURPOSEOFSUCHADEVICEISTHEPERFORMANCE/STRENGTHENHANCEMENTOFTHEWEARERITCANBEUSEDINTRAINING,INTHERAPY,ORSIMPLYASADEVICETOASSISTINFUNCTIONALDAILYLIVINGTHEIMPLICATIONOFTHETERM“WEARABLE”ISTHATTHEROBOTMUSTBEPORTABLE,LIGHTWEIGHT,ANDMOSTIMPORTANTLYSAFEINCONTRAST,AFACTORYFLOORROBOTISNONEOFTHESETHINGS,SOTHESIMPLEADAPTATIONOFEXISTINGTECHNOLOGYISNOTPOSSIBLETHESTANDARDAPPROACHTOWEARABLEROBOTDESIGNSUFFERSFROMTHREEMAJORLIMITATIONS1LOWBATTERYPOWERDENSITY；2MOTORSWITHLOW“STRENGTHTOWEIGHT”RATIOS；3WEIGHTANDSAFETYOFAMECHANICALTRANSMISSIONSYSTEMTHEGOALOFTHISWORKISTOREVIEWTHEDESIGNPROCESSOFALEADSCREWACTUATORTHERESULTOFWHICHWILLDEMONSTRATESIGNIFICANTIMPROVEMENTSOVERTHELIMITATIONSDESCRIBEDINITEMNUMBER3,IE,THEWEIGHTANDSAFETYOFTHEMECHANICALTRANSMISSIONSYSTEM2BACKGROUNDINTERESTINTHEAREAOFWEARABLEROBOTICSHASGROWNOVERTHELASTDECADETHERECENTSURGEOFINTERESTCANBEATTRIBUTEDTOADVANCEMENTSINELECTRONICMINIATURIZATION,MICROPROCESSORCAPABILITIES,ANDWIRELESSTECHNOLOGYPROLIFERATIONTHEFEASIBILITYOFAPORTABLECOMPUTERCONTROLLEDSTRENGTHENHANCINGDEVICEISCLOSERTOREALITYHOWEVER,ASIDEFROMTHEAVAILABILITYOFPORTABLECOMPUTATIONPLATFORMS,ISSUESOFTHEPHYSICALMECHANISMMUSTSTILLBEADDRESSEDTHEMAINISSUESINANYWEARABLEROBOTDEVELOPMENTAREPOWER,WEIGHT,ANDSAFETYHOWMUCHPOWERISAVAILABLETODOMECHANICALWORKHOWMUCHADDITIONALWEIGHTDOESTHEROBOTICDEVICEADDTOTHEPERSONAND,HOWCANTHISPOWERBETRANSFERREDANDSTILLMAINTAINSAFETYTHESAFEINTERACTIONBETWEENTHEWEARERANDTHEACTUATEDROBOTHASTOBETHEPRIMARYCONCERNINAWEARABLEROBOTDESIGNTHEPURPOSEOFAWEARABLEROBOTICSYSTEMISTOOFFSETTHEEFFORTORENERGYOFTHEOPERATORBYSOMEAMOUNTOFENERGYFROMASTORAGEDEVICE,IE,BATTERY,FUELCELL,ANDAIRTANKTHESHARINGOFTHEWORKLOADBETWEENTHEOPERATORANDTHEROBOTISHEAVILYINFLUENCEDBYACTUATOREFFICIENCIESANDTHEOVERALLSYSTEMWEIGHTTHEADDITIONALWEIGHTTHATTHEROBOTADDSTOTHEUSER,INMANYCASES,CANINCREASETHETOTALAMOUNTOFWORKREQUIREDTOACCOMPLISHAGIVENTASKTHISMEANSTHATTHEROBOTNOTONLYHASTOAUGMENTTHEOPERATORSABILITIES,BUTMUSTALSOCOMPENSATEFORITSOWNADDITIONALWEIGHT21ACTUATORCOMPARISONSHUMANSKELETALMUSCLEISTHE“GOLD”STANDARDBYWHICHMANYROBOTICACTUATORSARECOMPAREDKNOWNFORTHEIRGOOD“POWERTOWEIGHT”RATIOSANDEXCELLENTFORCEPRODUCTIONCAPABILITIES,SKELETALMUSCLEPERFORMANCEISWHATMOSTACTUATORDESIGNERSWOULDLIKETOMATCHINORDERTOMATCHTHEPERFORMANCECAPABILITIESOFSKELETALMUSCLE,ITISIMPORTANTTOKNOWSOMEOFITSMEASURESUNFORTUNATELY,COMMONTHROUGHOUTBIOLOGICALLITERATUREISAWIDEVARIATIONOFMEASUREDMUSCLEPROPERTIESALTHOUGHREPORTEDVALUESHAVEAWIDEVARIANCE,THESEVALUESCANSTILLGIVEASENSEOFSCALEINWHICHBIOLOGICALMATERIALSBEHAVEDATATABULATEDANDESTIMATEDFROMSEVERALSOURCESWEREUSEDTODESCRIBETHEATTRIBUTESOFHUMANMUSCLEPERFORMANCE,ANDTHERESULTOFWHICHCANBESEENINTABLE1TABLE1ACTUATORCOMPARISONCOMPARESVARIOUSACTUATORTYPESBYMECHANICALEFFICIENCY,POWERTOWEIGHTRATIO,“CORRECTED”POWERTOWEIGHTRATIO,ANDSTRENGTHTOWEIGHTRATIOMEASURESALLOWSTHEDIRECTCOMPARISONSTOBEMADEBASEDUPONUTILIZATIONOFAVAILABLEENERGYHOWEVER,BOTHOFTHESEPARAMETERSNEEDTOBEEXAMINEDINTHEDEVELOPMENTOFAWEARABLEROBOTICACTUATORCONSIDERTHATIFALLACTUATORSWERETOOPERATEAT100EFFICIENCY,THENTHEENTIREGROUPCOULDBECOMPAREDDIRECTLYBYTHEIRRESPECTIVEPOWERTOWEIGHTRATIOSHOWEVER,IFONLYTHEPOWERSTATEDINTHEPOWERTOWEIGHTRATIOWERESUPPLIEDTOEACHACTUATOR,THENBECAUSEOFTHEIRRESPECTIVEEFFICIENCY,ONLYAFRACTIONOFTHATPOWERWOULDBEYIELDEDASOUTPUTTHEREFORE,TOAPPROPRIATELYCOMPARETHEABOVEDESCRIBEDACTUATORS,THEIRCORRECTEDPOWERTOWEIGHT（C）RATIOSMUSTBEWCOMPUTED1WHEREISTHEMECHANICALEFFICIENCYANDPWTISTHEORIGINALPOWERTOWEIGHTRATIOTHERESULTSOFTHISCALCULATIONFORVARIOUSKINDSOFACTUATORSCANBESEENINTABLE1VALUESINTABLE1WEREOBTAINEDEITHERBYREFERENCEDLITERATUREORESTIMATIONSBASEDUPONTHATLITERATURETHEVALUESFORTHEDCMOTORAREFORTHEMAXONRE40MOTORTHEVALUESFORTHEGEARBOXCOMBINATIONWEREALSOFOUNDINTHEMAXON2004CATALOGVALUESFROMANELECTRICSERIESELASTICACTUATORWEREUSEDTOESTIMATETHESEPARAMETERSHOWEVER,ASIMILIARLYS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DTORQUE,THUSALLOWINGTHELOAD,FW,TOSELFLOWERABACKDRIVEABLELEADSCREWISABADIDEAFORACARJACK,BUTISDESIRABLEINAWEARABLEROBOTFORTHELEADANGLESINWHICHBACKDRIVEWILLOCCUR7LEADANGLEANDCOEFFICIENTOFFRICTIONAREALLTHATINFLUENCETHISCONDITION,REGARDLESSOFHOWHIGHTHELOADFORCEBECOMESFORAVERYLOWCOEFFICIENTOFFRICTIONSYSTEM,SUCHASABALLSCREW,BACKDRIVEISANINEVITABLECONSEQUENCE4PRACTICALCONSIDERATIONSIDEALLY,ASSHOWNINTHEPREVIOUSTEXT,ITWOULDBEDESIRABLETOREDUCEOURSCREWRADIUS,R,TOANALMOSTMICROSCOPICSCALEHOWEVER,THISISNOTAPRACTICALSOLUTION,NEITHERFROMADESIGNNORMANUFACTURINGPERSPECTIVEALTHOUGHSMALLSCREWDIAMETERSANDHIGHLEADANGLESAREDESIREDFROMTHEPERSPECTIVEOFWEIGHTANDEFFICIENCY,THEYMAYNOTALLOWTHEDESIGNERTOMEETTHESTRENGTHDEMANDSOFTHEPHYSICALSYSTEMISSUES,SUCHASAXIALYIELDING,COMPRESSIONBUCKLING,ANDMECHANISMBIND,NEEDTOBECONSIDEREDASWELLCONSIDERTHATASINGLEULTRATHINSCREWMAYBELIGHTWEIGHT,ALTHOUGHITMAYNOTBESTRONGENOUGHTOCARRYTHELOADREQUIREDBYTHESYSTEMASINGLEORSEVERALSCREWSCANBEUSED,BUTMUSTBESIZEDLARGEENOUGHTOHANDLETHELOADPLACEDUPONITASANOTE,THEREISNOWEIGHTADVANTAGETOUSINGSEVERALSMALLSCREWSTOCARRYALARGELOAD,ASTHECOMPUTATIONFORBOTHWEIGHTANDSTRESSAREDRIVENBYACROSSSECTIONALAREAOFTHESCREWHOWEVER,USINGSEVERALSMALLSCREWSTOCARRYTHELOADCANALLOWTHECONTINUEDUSEOFHIGHLEADANGLESANDTHUSOPERATEWITHHIGHEFFICIENCIES,EVENINTHEPRESENCEOFHIGHLOADSBYPUSHINGTHELIMITSOFRAWMATERIALPROPERTIESOFTHELEADSCREW,HIGHAXIALLOADINGCANBEACHIEVEDTHISAPPROACHWORKSBETTERFORATENSIONALSYSTEMTHANITDOESFORACOMPRESSIONBEARINGSYSTEMWHENCONSIDERINGTHECOMPRESSIVELOADINGOFALONGSLENDERSCREW,EULERBUCKLINGMUSTBEADDRESSEDSIMILARTOTHATOFTHEMCKIBBENACTUATORSOREVENHUMANMUSCLES,ALEADSCREWACTUATORCOULDBEDESIGNEDTOBEARATENSIONALLOADONLY,THUSELIMINATINGTHECONSIDERATIONOFBUCKLINGALTOGETHERCREATINGATENSIONONLYACTUATIONSYSTEMINAWEARABLEROBOTDOESNOTNECESSARILYMEANTHATANANTAGONISTICPAIRISREQUIREDINFACT,FORANASSISTANCEROBOT,ADISABLEDPERSONMAYONLYHAVEMUSCLEWEAKNESSINASINGLEACTUATEDDIRECTIONAND,THEREFORE,ASINGLETENSIONALACTUATORWOULDBEALLTHATISREQUIREDTOAIDTHATPERSON。FORTHOSEDESIGNERSWHOWOULDPUSHTHELIMITSOFTHESCREWRADIUSANDTHUSLEADANGLETOBEYONDTHATOFMAXIMUMEFFICIENCY,THEPRESENCEOFFRICTIONLIMITSJUSTHOWFARTHEANGLECANBEINCLINEDTHEPHYSICALINTERPRETATIONOFTHISISTHATTHESYSTEMWILLBINDORLOCKTHISCANBESEENBYEVALUATINGEQ（2）ANEVALUATIONOFTHEDENOMINATORINEQ（2）YIELDSTHEFOLLOWINGRELATION。8INADDITIONTOTHEPRACTICALCONSIDERATIONSLISTEDHERE,THEREEXISTSMANYOTHERISSUESTHATCOULDBEDETAILEDEXAMPLESOFWHICHMAYINCLUDETORSIONALSTIFFNESS/YIELDINGOREVENHEATDISSIPATIONEACHOFTHESEFACTORSAREIMPORTANTANDWORTHYOFCONSIDERATION,HOWEVER,THEPURPOSEOFTHISEXERCISEISTODEMONSTRATEANALTERNATIVETOTHETYPICALAPPROACHESOFDESIGNINGORSELECTINGSCREWSYSTEMSTHEBENEFITSOFTHISALTERNATIVEAPPROACHAREDIRECTLYAPPLICABLETOTHEDESIGNISSUESOFAWEARABLEROBOTICSYSTEM5EXAMPLEPROBLEMTODEMONSTRATEACRUDEDESIGNEXERCISE,CONSIDERTHEPEAKANKLEJOINTTORQUEDURINGGAITOFANABLEBODIEDORNORMALINDIVIDUALTHATWEIGHS80KGANDWALKSAT08HZSTEPPINGFREQUENCYTHEPEAKANKLETORQUEDURINGGAITISAPPROXIMATELY100NMTHISPEAKOCCURSATROUGHLY45OFTHEGAITCYCLE,AGAITCYCLEISDEFINEDBYTHEHEELSTRIKEOFAFOOTTOTHENEXTHEELSTRIKEOFTHESAMEFOOTTOEOFFISTHEPOINTINWHICHTHEWEIGHTOFTHEINDIVIDUALHASTRANSFERREDTOTHEOPPOSITELEGANDTHEINITIATIONOFSWINGBEGINSTHECONCLUSIONOFTHESWINGPHASEOFGAITPLACESTHEFOOTBACKINTOAHEELSTRIKEPOSITIONAGAINANDTHENTHENEXTGAITCYCLECANBEGINASANEXAMPLE,LETUSCONSIDERBUILDINGALEADSCREWACTUATORFORANKLEGAITASSISTANCEFOROURPROBLEM,LETUSASSUMETHELEVELTABLE2EXAMPLEPROBLEMACTUATORCOMPARISONCOMPARESLEADSCREWDESIGNSIANDIITOHUMANMUSCLEINTERMSOFMECHANICALEFFICIENCY,POWERTOWEIGHTRATIO,CORRECTEDPOWERTOWEIGHTRATIOANDSTRENGTHTOWEIGHTRATIO,MEASURESOFASSISTANCETOBEAT30ANDTHATTHEACTUATORACTSWITHA12CMMOMENTARMTOTHEANKLEJOINTTHESEVALUESCANBECHANGEDBUT,BASEDUPONPERSONALEXPERIENCE,AREREASONABLEINTHEIRSCALEUSINGTHESEVALUESANDPARAMETERSAVAILABLEFORACHOSENMAXONMOTOR,THERE40,ARANGEOFLEADLENGTHSFORTHISEXAMPLESOLUTIONHASBEENDETERMINEDTHERANGEOFPOSSIBLESCREWLEADSAREEXAMPLEPROBLEMRESULTSTWOLEADSCREWDESIGNSWEREGENERATEDTOSOLVETHISPROBLEMTHEFIRSTDESIGN,LEADSCREWI,ISADESIGNSOLVEDFORMAXIMUMEFFICIENCYASSUMINGALEADOF2MMANDA005,YIELDSANEFFICIENCYOF09FORTHESCREWAT435ANDARADIUSOF034MMWITHSUCHASMALLRADIUS,MULTIPLESCREWSARENEEDEDTOHOLDTHELOADEVENSO,ESTIMATESFORTHEACTUATORPOWERTOWEIGHTARE280W/KGPOWERTOWEIGHTHASBEENDETERMINEDBYDIVIDINGTHEPEAKPOWERREQUIREDINOUREXAMPLEBYTHEWEIGHTOFTHEMOTORANDESTIMATEDTRANSMISSIONSYSTEMFROMOURPREVIOUSWORK,THEWEIGHTOFTHEACCESSORYCOMPONENTSWASSCALEDPROPORTIONALLYTOTHEREDUCEDWEIGHTOFTHESCREWANDNUTTHESECONDDESIGN,LEADSCREWII,USESDIMENSIONSAVAILABLEFROMACOMMERCIALVENDORTHESCREWISESTIMATEDTOHAVEAN136ANDANEFFICIENCYOF082EVENWITHTHESELARGERDIMENSIONS,THEACTUATORSPOWERTOWEIGHTRATIOOF277W/KG074ISEXPECTEDTHERESULTSOFTHISEXAMPLEPROBLEMHAVEBEENTABULATEDFORTHEPURPOSEOFCOMPARISONTABLE2SHOWSTHENUMERICALRESULTSOFBOTHEXAMPLELEADSCREWDESIGNSTHESEVALUESARECOMPAREDTOTHEPREVIOUSVALUESTABULATEDFORADCMOTORALONE,ANDTHEESTIMATEDVALUESFORHUMANSKELETALMUSCLETHESTRENGTHTOWEIGHTPROPERTIESCALCULATEDFORTHESEEXAMPLESISBASEDUPONTHEPEAKFORCEREQUIREDBYOUREXAMPLE6DISCUSSIONINTHEANALYSISOFTHEMAXIMUMEFFICIENCYSOLUTION,LEADSCREWDESIGNI,ITWASSHOWNTHATASINGLESMALLRADIISCREWWILLNOTALWAYSHANDLETHELOADSREQUIREDOFITHOWEVER,ABUNDLEOFSCREWSOPERATINGINPARALLELCANPERFORMTHATTASKWITHTHESAMEHIGHEFFICIENCYALTHOUGHA034MMRADIUSSCREWWOULDNOTBEEASILYMANUFACTUREDUSINGTYPICALTECHNIQUES,ITISPOSSIBLETHATTHISKINDOFAPPROACHIE,USEMULTIPLESCREWSTOMAINTAINHIGHEFFICIENCYCOULDBEUSEFULFORAMEMSSCALEDDEVICEONECOULDIMAGINEACOMPACT“FORCEPACK”BUILTUPFROMMANYHIGHEFFICIENCYSMALLDIAMETERSCREWSWITHOUTGOINGTOTHEEXTREMESINEFFICIENCYFORAPARTICULARSCREWDESIGN,ITWASSHOWNTHATFORLEADSCREWDESIGNII,AFEASIBLESOLUTIONEXISTSFOROUREXAMPLEPROBLEMOFANKLEGAITCORRECTEDPOWERTOWEIGHTVALUESWEREOBTAINEDTHATAREVERYCLOSETOTHOSEDISCUSSEDFORHUMANMUSCLEUSINGASIMILARAPPROACH,ABALLSCREWMECHANISMCOULDBENEFITINPERFORMANCE,ASWELLTHEGENERALAPPROACHTOCREATINGBACKDRIVEABLE,LOWWEIGHT,ANDHIGHEFFICIENCYSCREWSYSTEMCANMAKEADCMOTORBASEDACTUATORACOMPETITIVESOLUTIONFORWEARABLEROBOTAPPLICATIONSFIG3PROTOTYPEACTUATOR,HIGHEFFICIENCYLEADSCREWMENTIONEDEARLIER,AWEARABLEROBOTACTUATORMUSTNOTONLYHAVEGOODPERFORMANCECAPABILITIES,BUTMUSTBESAFEFORITSWEARERINTHECONSIDERATIONOFSAFETY,BACKDRIVEINAWEARABLELEADSCREWACTUATORISDESIREDBACKDRIVEALLOWSTHENONPOWEREDUNITTOBEPOSITIONEDFREELYBYITSOPERATOR,ANDTHUSMINIMIZESITSENCUMBRANCEONTHEWEARERINANOTHERCONSIDERATION,DESIGNINGAFREESPINREGIONATTHEENDOFRANGEOFTHESCREWCANPREVENTDAMAGETOBOTHTHEMOTORANDTHEWEARERDAMAGETOTHEPERSONISAVOIDEDBYPLACINGTHEENDRANGESOFTHESCREWWITHINTHESAFEPHYSIOLOGICALLIMITOFTHEWEARERLASTLY,SAFEINTERACTIONCANBEMAINTAINEDBYTHEUSEOFBREAKAWAYATTACHMENTS,WHICHCANBEDESIGNEDTOSNAPFREEONCEADANGEROUSLYHIGHFORCEISENCOUNTEREDALLOFTHESEAPPROACHESAREIMPORTANTCONSIDERATIONSANDSHOULDBEADDRESSEDEARLYINTHEDESIGNPROCESSPLACINGPOWEREDSTRONGMECHANICALDEVICESONAPERSONMUSTINCLUDESPECIALPRECAUTIONSPRECAUTIONSMUSTGOBEYONDSOFTWAREORCONTROLLERSHENCE,THEYSHOULDBEINCLUDEDINTHEMECHANICALDESIGNASWELLENSURINGTHESAFETYOFTHEWEARERISATOPPRIORITYINANYASSISTANCEROBOTDESIGNASANADDEDNOTE,OURLABORATORYHASALSOINVESTIGATEDOTHERTYPESOFWEARABLEACTUATORSFIG3USINGTHESETECHNIQUESHELPEDKEEPTHEOVERALLSIZEANDWEIGHTOFOURDEVICETOAMINIMUM7CONCLUSIONSAWEARABLEROBOTICACTUATORMUSTHAVEAGOODPOWERTOWEIGHTRATIO,AGOODMECHANICALEFFICIENCY,AGOODSTRENGTHTOWEIGHTRATIO,ANDMUSTBESAFEFORADCMOTORWITHGOODPOWERTOWEIGHT,THEONLYWAYTOIMPROVEITSSTRENGTHISTOADDATRANSMISSIONSYSTEMTRADITIONALLY,THISADDITIONHASCAUSEDTHEPOWERTOWEIGHTPERFORMANCEOFADCMOTORBASEDACTUATORTOPLUMMETHOWEVER,THROUGHAPPROPRIATEDESIGNANDMATERIALSELECTIONALEADSCREWACTUATORCANBECREATEDTHATDOESNOTSIGNIFICANTLYINCREASETHEWEIGHTOFTHEACTUATORBEYONDTHATOFTHEDCMOTORALONEOURMETHODOLOGYCANBESTBEUSEDTODESIGNALEADSCREWORABALLSCREWFORFORCEAPPLICATIONS,SUCHASAWEARABLEASSISTANCEROBOT轻量级丝杠作动器设计在便携的机器人的应用机械设计报凯文W霍兰德托马斯G唐一个便携机器人是直接与它的用户联系的一个受控和开动的设备。同样，也要求这个设备必须也是便携的，轻量级的，最重要的是安全的。为了达到这些目标。标准丝杠的设计通常不能很好的按要求执行这些。典型的丝杠有很低投球角度和大的半径，从而产生很低的机械效率和很大的重量。可是，使用文本中的设计程序，效率和重量是被改进的因而可以产生一种与人的肌肉相似的丝杠系统。例子中的问题说明一个可行性的丝杠设计应该是277的功率质量比，接近驱动