自动化专业外文翻译--自动控制的发展历史

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1、HISTORYOFAUTOMATICCONTROLFeedbackcontrolisthebasicmechanismbywhichsystems,whethermechanical,electrical,orbiological,maintaintheirequilibriumorhomeostasis.Inthehigherlifeforms,theconditionsunderwhichlifecancontinuearequitenarrow.Achangeinbodytemperatureofhalfadegreeisgeneral

2、lyasignofillness.Thehomeostasisofthebodyismaintainedthroughtheuseoffeedbackcontrol[Wiener1948].AprimarycontributionofCRDarwinduringthelastcenturywasthetheorythatfeedbackoverlongtimeperiodsisresponsiblefortheevolutionofspecies.In1931V.Volterraexplainedthebalancebetweentwopop

3、ulationsoffishinaclosedpondusingthetheoryoffeedback.Theuseoffeedbacktocontrolasystemhasafascinatinghistory.ThefirstapplicationsoffeedbackcontrolappearedinthedevelopmentoffloatregulatormechanismsinGreeceintheperiod300to1B.C.Thewaterclockofktesibiosusedafloatregulator.Anoilla

4、mpdevisedbyPhiloninapproximately250B.C.Usedafloatregularinanoillampformaintainingaconstantlevelsoffueloil.HeronofAlexandria,wholivedinthefirstcenturyA.D,publishedabookentitledPneumatica,whichoutlinedseveralformsofwater-levelmechanismsusingfloatingregulatorsThefirstfeedbacks

5、ystemtobeinventedinmodernEuropewasthetemperatureregulatorofCornelisDrebb(1572-1633)ofHollandDennisPapininventedthefirstpressureregulatorforsteamboilersIn1681.Papin'pressureregulatorwasaformofsafetyRegulatorSimilartoapressure-cookervalve.Feedbackcontrolmaybedefinedastheuseof

6、differencesignals,determinedbycomparingtheactualvaluesofsystemvariablestotheirdesiredvalues,asameansofcontrollingasystem.Aneverydayexampleofafeedbackcontrolsystemisanautomobilespeedcontrol,whichusesthedifferencebetweentheactualandthedesiredspeedtovarythefuelflowrate.Sinceth

7、esystemoutputisusedtoregulateitsinput,suchadeviceissaidtobeaclosed-loopcontrolsystem.Thefirsthistoricalfeedbacksystem,claimedbyRussia,isthewater-levelfloatregulatorsaidtohavebeeninventedbyI.Polzunovin1765.Thefloatdetectsthewaterlevelandcontrolsthevalvethatcoversthewaterinle

8、tintheboiler.Therehavebeenmanydevelopmentsinautomaticcontroltheoryduringrecentyear